Clinical-radiomics nomogram for the risk prediction of esophageal fistula in patients with esophageal squamous cell carcinoma treated with intensity-modulated radiation therapy or volumetric-modulated arc therapy.

Background: Esophageal fistula (EF) is a serious adverse event as a result of radiotherapy in patients with esophageal cancer (EC). We aimed to identify the predictive factors and establish a prediction model of EF in patients with esophageal squamous cell carcinoma (ESCC) who underwent intensity-modulated radiation therapy (IMRT) or volumetric-modulated arc therapy (VMAT). Methods: Patients with ESCC treated with IMRT or VMAT from January 2013 to December 2020 at Xijing Hospital were retrospectively analyzed. Ultimately, 43 patients with EF and 129 patients without EF were included in the analysis and propensity-score matched in a 1:3 ratio. The clinical characteristics and radiomics features were extracted. Univariate and multivariate stepwise logistic regression analyses were used to determine the risk factors associated with EF. Results: The median follow-up time was 24.0 months (range, 1.3-104.9 months), and the median overall survival (OS) was 13.1 months in patients with EF. A total of 1,158 radiomics features were extracted, and eight radiomics features were selected for inclusion into a model for predicting EF, with an area under the receiver operating characteristic curve (AUC) value of 0.794. Multivariate analysis showed that tumor length, tumor volume, T stage, lymphocyte rate (LR), and grade IV esophagus stenosis were related to EF, and the AUC value of clinical model for predicting EF was 0.849. The clinical-radiomics model had the best performance in predicting EF with an AUC value of 0.896. Conclusions: The clinical-radiomics nomogram can predict the risk of EF in ESCC patients and is helpful for the individualized treatment of EC.

Diabetes-related Screw Loosening: The Distinction of Surgical Sites and the Relationship among Diabetes, Implant Stabilization and Clinical Outcomes.

OBJECTIVES: Diabetes mellitus (DM) is correlated with poor clinical outcomes in spinal surgery. However, the effect of it on screw stabilization has not been investigated. The aim of this study was to evaluate the screw loosening rate and postoperative outcomes in diabetic patients and to identify potential risk factors associated with loosening. METHODS: This was a retrospective study. Two hundred and forty-three patients who received cervical or lumbar internal fixation between 2015 and 2019 were enrolled. Screw loosening was assessed on radiography, and clinical outcomes were evaluated by the improvement of visual analogue scale (VAS), Oswestry disability index (ODI) or Japanese Orthopaedic Association (JOA) scores. The relationship of DM, screw loosening and clinical outcomes were analyzed with chi-square tests and regression analyses. RESULTS: One hundred and twenty-two patients (50.2%) with diabetes were included in this study. Diabetes led to the increase of the rate of screw loosening in the lumbar spine, while the loosening rate did not vary significantly in the cervical spine. The occurrence of screw loosening in the lumbar spine was more likely to be associated with clinical outcomes for motor performance including walking and sitting. However, no significant effect on JOA and VAS scores in the cervical spine of screw loosening was found. Moreover, the history of DM affected the outcomes of the patients who underwent spinal surgery. CONCLUSION: DM had an adverse effect on screw stabilization. The impaired improvement of clinical outcomes in diabetics after spinal surgery was related to screw loosening. In addition to the direct effects on operative wounds and neural function, the impact on the screws due to DM was also worth noting.

Re-irradiation for local primary-recurrence esophageal squamous cell carcinoma treated with IMRT/VMAT.

PURPOSE: Local primary-recurrence of esophageal squamous cell carcinoma (ESCC) after definitive treatment has the potential for increasing overall survival with re-irradiation (Re-RT), especially with advanced technique. This study aimed to evaluate the efficacy and toxicities of Re-RT using intensity-modulated radiotherapy (IMRT)/volumetric modulated arc therapy (VMAT) for local primary-recurrence of ESCC. MATERIALS AND METHODS: A total of 130 ESCC patients with local primary-recurrence from Xijing hospital between 2008 and 2021 were enrolled and 30 patients underwent IMRT/VMAT based salvage Re-RT. Cox regression analysis was used to analyze the prognostic factors for overall survival (OS) and after recurrence survival (ARS). The toxicities of 30 patients receiving Re-RT were also assessed. RESULTS: The median OS and ARS of the 130 recurrent patients were 21 months (1-164 months) and 6 months (1-142 months). The 1-, 2-, and 3-year OS rates were 81.5%, 39.2%, and 23.8%, respectively. Besides, the 1-, 2-, and 3-year ARS rates were 30.0%, 10%, and 6.2%. Multivariate analysis showed that Re-RT ± chemotherapy (p = 0.043) and chemotherapy alone (p < 0.001) and esophageal stents (p = 0.004) were independent prognostic factors for OS. The median OS of 30 patients treated with Re-RT were significantly better than that of 29 patients treated with chemotherapy (34.5 months vs. 22 months, p = 0.030). Among 30 ESCC patients treated with Re-RT, the median OS and ARS were 34.5 months (range 12-163 months) and 6 months (range 1-132 months), respectively. The recurrence-free interval (RFI) (> 12 months) and initial radiation dose (> 60 Gy) were significantly associated with improved OS. Radiation esophagitis (Grade 1-2) occurred in 16 patients and myelosuppression (Grade1-2) occurred in 10 patients. Grade 3 toxicities (radiation esophagitis and myelosuppression) were only 13.3%. There were no grade 4 toxicities. CONCLUSION: Our results demonstrated that IMRT/VMAT-based Re-RT was an effective therapeutic option for ESCC patients with local primary-recurrence compared with chemotherapy alone or without any treatment. Re-RT had improved OS but unfavorable ARS.

Spatiotemporal Regulation of Injectable Heterogeneous Silk Gel Scaffolds for Accelerating Guided Vertebral Repair.

Osteoporotic vertebral fracture is jeopardizing the health of the aged population around the world, while the hypoxia microenvironment and oxidative damage of bone defect make it difficult to perform effective tissue regeneration. The balance of oxidative stress and the coupling of vessel and bone ingrowth are critical for bone regeneration. In this study, an injectable heterogeneous silk gel scaffold which can spatiotemporally and sustainedly release bone mesenchymal stem cell-derived small extracellular vesicles, HIF-1α pathway activator, and inhibitor is developed for bone repair and vertebral reinforcement. The initial enhancement of HIF-1α upregulates the expression of VEGF to promote angiogenesis, and the balance of reactive oxygen species level is regulated to effectively eliminate oxidative damage and abnormal microenvironment. The subsequent inhibition of HIF-1α avoids the overexpression of VEGF and vascular overgrowth. Meanwhile, complex macroporous structures and suitable mechanical support can be obtained within the silk gel scaffolds, which will promote in situ bone regeneration. These findings provide a new clinical translation strategy for osteoporotic vertebral augmentation on basis of hypoxia microenvironment improvement.

Impact of probiotics supplement on the gut microbiota in neonates with antibiotic exposure: an open-label single-center randomized parallel controlled study.

BACKGROUND: Antibiotics, a common strategy used for neonatal infection, show consistent effect on the gut microbiota of neonates. Supplementation with probiotics has become increasingly popular in mitigating the loss of the gut microbiota. However, no clear consensus recommending the use of probiotics in the infection of neonates currently exists. This study examined the effects of probiotics on the gut microbiota of infectious neonates when used concurrently with or during the recovery period following antibiotic therapy. METHODS: Fifty-five full-term neonates diagnosed with neonatal infections were divided into the following groups: NI (no intervention, antibiotic therapy only), PCA (probiotics used concurrently with antibiotics), and PAA (probiotics used after antibiotics). The NI group received antibiotic treatment (piperacillin-tazobactam) for 1 week and the PCA group received antibiotic treatment together with probiotics (Bifidobacterium longum, Lactobacillus acidophilus, and Enterococcus faecalis) for 1 week. The PAA group received antibiotic treatment for 1 week followed by probiotics for 1 week. Fecal samples were collected at four time nodes: newborn, 1 week, 2 weeks, and 42 days after birth. The composition of the gut microbiota was determined by the high-throughput sequencing of 16S rRNA amplicons. RESULTS: Antibiotic exposure was found to dramatically alter gut microbiota, with a significant decrease of Bifidobacterium and Lactobacillus. The use of probiotics did not restore the overall diversity of the gut microbiota. However, using probiotics simultaneously with the antibiotics was found to be beneficial for the gut microbiota as compared to delaying the use of probiotics to follow treatment with antibiotics, particularly in promoting the abundance of Bifidobacterium. CONCLUSIONS: These results suggest that the early use of probiotics may have a potential ability to remodel the gut microbiota during recovery from antibiotic treatment. However, further study is required to fully understand the long-term effects including the clinical benefits.

Effects of high-flux hemodialysis combined with levocarnitine on vascular calcification, microinflammation, hepcidin, and malnutrition of elderly patients on maintenance hemodialysis.

BACKGROUND: This study was to investigate the effect of high-flux hemodialysis (HD) combined with levocarnitine on vascular calcification, microinflammation, hepcidin, and malnutrition in elderly patients on maintenance HD (MHD). METHODS: 75 MHD elderly patients admitted to hospital between 1st September 2017 and 31st August 2019 were selected as the study subjects. They were randomly divided by digital table into three groups: low-flux group (n=25), high-flux group (n=25) and joint group (n=25). In the low-flux group, dialyzer had an ultrafiltration coefficient 12 mL/(h·mmHg) and effective surface area of 1.4 m2 compared with 59 mL/(h·mmHg) and 1.8 m2 in the high-flux group. After treatment, the calcification of blood vessels was examined by lateral X-ray, pelvic plain film and bilateral positive position. For patients in all groups, the concentrations of parathyroid hormone (PTH) and ß 2-microglobulin (ß 2-MG) in serum were measured by automatic chemiluminescence; levels of interleukin-6, C-reactive protein (CRP), and tumor necrosis factor alpha (TNF-α) were measured by ELISA before and after treatment; and the level of hepcidin was measured by ELISA. Before and 12 weeks after the treatment, the nutritional status of the patients was evaluated by modified quantitative subjective global assessment (MQSGA), hemoglobin (Hb) and red blood cell count (RBC). Complications in the three groups were recorded, including nausea, chest pain, hypotension, hypertension, pruritus, dry heat, muscle spasm, arrhythmia, and restless legs. RESULTS: Vascular calcification in the joint group was better than the low-flux and high-flux groups (P<0.05). After treatment, the serum PTH and ß 2-mg concentrations in the joint group were lower than those in the other two groups (P<0.05), and the levels of IL-6, CRP, TNF-α and hepcidin in the joint group were significantly lower than those before treatment (P<0.05). After treatment, the MQSGA scores in the joint group were lower than those in the low-flux and high-flux groups (P<0.05), and Hb and RBC were higher (P<0.05). CONCLUSIONS: The combination of high-flux HD and levocarnitine in elderly patients on MHD can increase the clearance of medium and large molecular toxins, effectively correct malnutrition, alleviate microinflammation, delay the progress of vascular calcification, and is safe.

Impairment of type H vessels by NOX2-mediated endothelial oxidative stress: critical mechanisms and therapeutic targets for bone fragility in streptozotocin-induced type 1 diabetic mice.

Rationale: Mechanisms underlying the compromised bone formation in type 1 diabetes mellitus (T1DM), which causes bone fragility and frequent fractures, remain poorly understood. Recent advances in organ-specific vascular endothelial cells (ECs) identify type H blood vessel injury in the bone, which actively direct osteogenesis, as a possible player. Methods: T1DM was induced in mice by streptozotocin (STZ) injection in two severity degrees. Bony endothelium, the coupling of angiogenesis and osteogenesis, and bone mass quality were evaluated. Insulin, antioxidants, and NADPH oxidase (NOX) inhibitors were administered to diabetic animals to investigate possible mechanisms and design therapeutic strategies. Results: T1DM in mice led to the holistic abnormality of the vascular system in the bone, especially type H vessels, resulting in the uncoupling of angiogenesis and osteogenesis and inhibition of bone formation. The severity of osteopathy was positively related to glycemic levels. These pathological changes were attenuated by early-started, but not late-started, insulin therapy. ECs in diabetic bones showed significantly higher levels of reactive oxygen species (ROS) and NOX 1 and 2. Impairments of bone vessels and bone mass were effectively ameliorated by treatment with anti-oxidants or NOX2 inhibitors, but not by a NOX1/4 inhibitor. GSK2795039 (GSK), a NOX2 inhibitor, significantly supplemented the insulin effect on the diabetic bone. Conclusions: Diabetic osteopathy could be a chronic microvascular complication of T1DM. The impairment of type H vessels by NOX2-mediated endothelial oxidative stress might be an important contributor that can serve as a therapeutic target for T1DM-induced osteopathy.

In Situ Regulation of Macrophage Polarization to Enhance Osseointegration Under Diabetic Conditions Using Injectable Silk/Sitagliptin Gel Scaffolds.

As a chronic inflammatory disease, diabetes mellitus creates a proinflammatory microenvironment around implants, resulting in a high rate of implant loosening or failure in osteological therapies. In this study, macroporous silk gel scaffolds are injected at the bone-implant interface for in situ release of sitagliptin that can regulate macrophage response to create a prohealing microenvironment in diabetes mellitus disease. Notably, it is discovered that sitagliptin induces macrophage polarization to the M2 phenotype and alleviates the impaired behaviors of osteoblasts on titanium (Ti) implants under diabetic conditions in a dose-dependent manner. The silk gel scaffolds loaded with sitagliptin elicite a stronger recruitment of M2 macrophages to the sites of Ti implants and a significant promotion of osteointegration, as compared to oral sitagliptin administration. The results suggest that injectable silk/sitagliptin gel scaffolds can be utilized to modulate the immune responses at the bone-implant interface, thus enhancing bone regeneration required for successful implantation of orthopedic and dental devices in diabetic patients.

Promotion of osteointegration under diabetic conditions by a silk fibroin coating on 3D-printed porous titanium implants via a ROS-mediated NF-κB pathway.

Clinical evidence indicates the compromised application of titanium implants (TIs) in diabetics, associated with reactive oxygen species (ROS) overproduction at the bone-implant interface. Silk fibroin (SF) has displayed impressive biocompatibility in the application of biomedical material and optimal anti-diabetic effects in oriental medicine. We proposed that SF-coated titanium implants (STIs) could alleviate diabetes-induced compromised osteointegration, which has rarely been reported before. To confirm this hypothesis and explore the underlying mechanisms, rat osteoblasts cultured on 3-dimensional (3D) -printed titanium implants (TIs) and STIs were subjected to normal serum (NS), diabetic serum (DS), DS with N-acetyl-L-cysteine (a ROS inhibitor) or SN50 (an NF-κB inhibitor). Anin vivostudy was performed on diabetic sheep with TIs or STIs implanted into bone defects on thecrista iliaca. The results demonstrated that ROS overproduction induced by diabetes lead to osteoblast dysfunctions and cellular apoptosis on the TI substrate, associated with the activation of an NF-κB signaling pathway in osteoblasts. Importantly, the STI substrate significantly attenuated ROS production and NF-κBp65 phosphorylation, thereby ameliorating the osteoblast biological dysfunctions. These results were further confirmedin vivoby the improved osteointegration of the STIs, as evidenced by Micro-CT and histological examinations compared with those of TIs. These results demonstrated that the ROS-mediated NF-κB signaling pathway played a crucial role in diabetes-induced implant destabilization. Importantly, the SF coating, as a promising material for biomaterial-engineering, markedly improved the clinical treatment effect of TIs under diabetic conditions, possibly associated with the suppression of the NF-κB pathway.

All-Aqueous-Processed Injectable In Situ Forming Macroporous Silk Gel Scaffolds for Minimally Invasive Intracranial and Osteological Therapies.

Hydrogels are widely utilized in regenerative medicine for drug delivery and tissue repair due to their superior biocompatibility and high similarity to the extracellular matrix. For minimally invasive therapies, in situ forming gel scaffolds are desirable, but technical challenges remain to be overcome to achieve the balance between tissue-like strength and cell-sized porosity, especially for intracranial and osteological therapies. Here, a new method-inspired by the liquid crystalline spinning process in natural silk fibers-is reported for preparing injectable silk gel scaffolds with favorable preclinical efficacy and unique characteristics including 1) in situ gelling for minimally invasive surgeries, 2) controllable porosity for efficient cellular infiltration and desirable degradation, 3) resilient and tunable mechanical properties that are compatible with the modulus regime of native soft tissues, and 4) all-aqueous processing that avoids toxic solvents and enables facile loading of bioactive agents. Moreover, hierarchically structured heterogeneous silk gel scaffolds with variable porosity and bioactive agent gradients within 3D matrices can be achieved for sustained drug release and guided tissue regeneration. Preclinical efficacy studies in rodent models show efficient bacterium and glioma inhibition and positive effects on bone regeneration and vascularization.

The impact of sitagliptin on macrophage polarity and angiogenesis in the osteointegration of titanium implants in type 2 diabetes.

BACKGROUND: Clinical evidence indicates that sitagliptin treatment improves bone quality in diabetic patients, but the mechanisms involved remain elusive. Here, we studied the role of angiogenesis with sitagliptin treatment in diabetes-induced poor osteointegration of titanium implants and the underlying mechanisms. METHODS: In vitro, Human Umbilical Vein Endothelial Cells (HUVECs) incubated on titanium (Ti) surface were subjected to 1) normal milieu (NM); 2) diabetic milieu (DM); 3) DM + sitagliptin; 4) NM + macrophage; 5) DM + macrophage; or 6) DM + macrophage + sitagliptin. Microphage and HUVECs were cultured alone or co-cultured in a Transwell system. In vivo, DM was induced by high-fat diet and administration of streptozotocin (STZ) in rats. Titanium screws were implanted in the femurs of rats in three groups: Control, DM, Sitagliptin-treated DM. RESULTS: In vitro, when cells were incubated alone, DM caused M1 polarization of macrophage, evidenced by the increased iNOS and decreased CD206 expressions, and obvious dysfunctions of HUVECs. The DM-induced injury of endothelial cells were significantly worsened when the two cells were co-cultured. The addition of sitagliptin markedly reversed the changes of macrophage but not of HUVECs in DM when cells were cultured alone. When cells co-cultured, however, both the abnormal macrophage polarization and the endothelial impairment in DM was significantly alleviated by sitagliptin. In vivo, compared with normal animals, DM animals showed imbalanced M1/M2 polarization, angiogenesis inhibition and poor bone formation on the bone-implant interface (BII), which were significantly ameliorated by sitagliptin treatment. CONCLUSION: Our results demonstrate macrophage polarization imbalance as a crucial mechanism underlying the impaired angiogenesis and bone healing in diabetes, and provide sitagliptin as a promising novel drug for biomaterial-engineering to improve the osteointegration of titanium implants in diabetic patients.

Nail Gun Injury of the Spine: Case Report and Review of the Literature.

BACKGROUND: Since the first report about nail gun injuries in 1959, there has been an average of approximately 37,000 patients hurt by nail guns and treated in emergency departments. Carotid arterial injury by nail gun has been reported, but vertebral artery damage is extremely rare. CASE DESCRIPTION: A 42-year-old man was transported to the emergency department after suffering an accidental self-inflicted nail gun injury to the left lateral aspect of his neck. Radiographic imaging of the cervical spine revealed a 3.1-cm metallic nail in the C5 region. A computed tomography (CT) angiogram revealed the nail passing through the left C5 transverse foramen and compressing the left vertebral artery. He was immediately brought to the operating room for removal of the nail. At 1-month follow-up, the patient did not have any neck complaints and postoperative CT angiogram indicated the patient was asymptomatic with no signs of complication or infection. CONCLUSIONS: Based on our experience and a review of the literature, in terms of treating a nail gun injury to the cervical spine, we would like emphasize that preoperative CT scan or CT angiogram is necessary to assess the location and shape of the nail, especially nails with barbers or washers. Improving awareness of the risk from accidental nail gun trauma may lead to better prevention of this rare but potentially life-threatening injury.

Angiogenesis impairment by the NADPH oxidase-triggered oxidative stress at the bone-implant interface: Critical mechanisms and therapeutic targets for implant failure under hyperglycemic conditions in diabetes.

Mechanism underlying the diabetes-induced poor osteointegration of implants remains elusive, making it a challenge to develop corresponding solutions. Here, we studied the role of angiogenesis in the diabetes-induced poor bone repair at the bone-implant interface (BII) and the related mechanisms. In vivo, titanium screws were implanted in the femurs of mice, and, in vitro, vascular endothelial cell (VEC) was cultured on titanium surface. Results showed that, compared with normal milieu (NM), diabetic milieu (DM) led to angiogenesis inhibition around implants which resulted in reduced osteoprogenitors and poor bone formation on BII in vivo. In vitro, DM caused significant increase of NADPH oxidases (NOX), dysfunction of mitochondria and overproduction of reactive oxygen species (ROS) in VEC on titanium surface, inducing obvious cell dysfunction. Both Mito-TEMPO (Mito, a mitochondria-targeted ROS antagonist) and apocynin (APO, a NOX inhibitor) effectively attenuated the oxidative stress and dysfunction of VEC, with the beneficial effects of APO significantly better than those of Mito. Further study showed that the diabetes-induced metabolic disturbance of VEC was significantly related to the increase of advanced glycation end products (AGEs) at the BII. Our results suggested that the AGEs-related and NOX-triggered cellular oxidative stress leads to VEC dysfunction and angiogenesis impairment at the BII, which plays a critical role in the compromised implant osteointegration under diabetic conditions. These demonstrated new insights into the BII in pathological states and also provided NOX and AGEs as promising therapeutic targets for developing novel implant materials to accelerate the angiogenesis and osteointegration of implants in diabetic patients with hyperglycemia. STATEMENT OF SIGNIFICANCE: The high failure rate of bone implants in diabetic patients causes patients terrible pain and limits the clinical application of implant materials. The mechanism underlying this phenomenon needs elucidation so that it would be possible to develop corresponding solutions. Our study demonstrated that the AGEs-related and NOX-triggered oxidative stress of VEC leads to angiogenesis impairment at the bone-implant interface (BII) in diabetes. These are critical mechanisms underlying the compromised implant osteointegration in diabetic hyperglycemia. These provide new insights into the BII in diseased states and also suggest NOX and AGEs as crucial therapeutic targets for developing novel implant materials which could modulate the oxidative stress on BII to get improved osteointegration and reduced implant failure, especially in diabetic patients.

Lactic acid of PLGA coating promotes angiogenesis on the interface between porous titanium and diabetic bone.

The diabetes-related high failure risk for endosseous implants needs efficacious methods to improve osteointegration on the bone-implant interface (BII). Poly(lactic-co-glycolic) acid (PLGA) is widely used in tissue engineering but its effects on the BII in diabetes remain unclear. To clarify this issue, 3D-printed porous titanium implants (TI) with and without PLGA coating were fixed in the bone defects of sheep in vivo, and vascular endothelial cells (VEC) and osteoblasts were incubated on the implant surface under normal conditions (NC) and diabetic conditions (DC) in vitro. The results showed that the PLGA coating promoted angiogenesis on the BII and the osteointegration of TI in diabetic sheep. The PLGA coating attenuated the DC-induced dysfunctions of VEC but not of osteoblasts. When VEC and osteoblasts were co-cultured in DC, the PLGA coating showed protective effects on the osteoblasts. Lactic acid (LA) but not glycolic acid (GA), both of which are degradation products of PLGA, induced similar effects to those of PLGA. These results suggest that PLGA coating on TI could promote angiogenesis in diabetes by its degradation production of LA, thus indirectly improving the bone formation on BII. Furthermore, PLGA exerted its effects, at least partially, through inhibiting the pathological effects of advanced glycation end products (AGEs) on the BII. This is the first study of the effects of PLGA on angiogenesis on the BII and the first findings on the inhibitory effects of PLGA on AGEs. Our findings demonstrate that PLGA is a promising interface-modification component for fabricating implants with better angiogenesis and osteointegration on the BII under diabetic conditions. This strategy might be applicable for reducing implant failure in diabetic patients.

Adiponectin improves the osteointegration of titanium implant under diabetic conditions by reversing mitochondrial dysfunction via the AMPK pathway in vivo and in vitro.

Diabetes-induced reactive oxygen species (ROS) overproduction would result in compromised osteointegration of titanium implant (TI) and high rate of implant failure, yet the underlying mechanisms remain elusive. Adiponectin (APN) is a fat-derived adipocytokine with strong antioxidant, mitochondrial-protective and anti-diabetic efficacies. We hypothesized that mitochondrial dysfunction under diabetes may account for the oxidative stress in osteoblasts and titanium-bone interface (TBI) instability, which could be ameliorated by APN. To test this hypothesis, we incubated primary rat osteoblasts on TI and tested the cellular behaviors when subjected to normal milieu (NM), diabetic milieu (DM), DM+APN, DM+AICAR (AMPK activator) and DM+APN+Compound C (AMPK inhibitor). In vivo, APN or APN+Compound C were administered to diabetic db/db mice with TI implanted in their femurs. Results showed that diabetes induced structural damage, dysfunction and content decrease of mitochondria in osteoblasts, which led to ROS overproduction, dysfunction and apoptosis of osteoblasts accompanied by the inhibition of AMPK signaling. APN alleviated the mitochondrial damage by activating AMPK, thus reversing osteoblast impairment and improving the osteointegration of TI evidenced by Micro-CT and histological analysis. Furthermore, AICAR showed beneficial effects similar to APN treatment, while the protective effects of APN were abolished when AMPK activation was blocked by Compound C. This study clarifies mitochondrial dysfunction as a crucial mechanism in the impaired bone healing and implant loosening in diabetes, and provides APN as a novel promising active component for biomaterial-engineering to improve clinical performance of TI in diabetic patients. STATEMENT OF SIGNIFICANCE: The loosening rate of titanium implants in diabetic patients is high. The underlying mechanisms remain elusive and, with the rapid increase of diabetic morbility, efficacious strategies to mitigate this problem have become increasingly important. Our study showed that the mitochondrial impairment and the consequent oxidative stress in osteoblasts at the titanium-bone interface (TBI) play a critical role in the diabetes-induced poor bone repair and implant destabilization, which could become therapeutic targets. Furthermore, adiponectin, a cytokine, promotes the bio-functional recovery of osteoblasts and bone regeneration at the TBI in diabetes. This provides APN as a novel bioactive component used in material-engineering to promote the osteointegration of implants, which could reduce implant failure, especially for diabetic patients.

[Research on Measurement Method of Gas Velocity Combined Absorption Spectroscopy Technique and Cross-Correlation].

For the small frequency shift and large error of tunable diode laser absorption spectroscopy (TDLAS) velocity method based on Doppler Effect in measuring the gas velocity, velocity measurement method combined fixed wavelength absorption spectroscopy and cross correlation is proposed in this paper. Considering the characteristics of the hydrocarbon fuel combustion products, 7 158.597 cm(- 1) absorption line of H(2)O molecular was selected. Through arranging two beams of fixed wavelength absorption measurement point of upstream and downstream, the gas velocity can be calculated by analyzing the cross-correlation properties of the two signals. The flat flame burner experiment system was used in the experimental research of the velocity measurement. The change of gas velocity with time under variable working condition was obtained. Under the same condition, numerical calculation is carried out. And the measurement results are compared with the results of the numerical simulation with relative deviation less than 8%. Then the method is preliminarily applied to measure the high speed plume of the kerosene-fueled Rocket Based Combined Cycle (RBCC) engine, and the upstream and downstream fluctuant signals of detectors were obtained. The velocity of the plume was calculated with cross correlation analysis which verifies the feasibility of this method. The experimental results show that the gas velocity measurement method has a wide measuring range with high measuring accuracy and little environment interference. The method proposed in this paper provides a simple and reliable method for the measurement of engine gas velocity.

Dual targeting and enhanced cytotoxicity to HER2-overexpressing tumors by immunoapoptotin-armored mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are promising vehicles for the delivery of anticancer agents in cancer therapy. However, the tumor targeting of loaded therapeutics is essential. Here, we explored a dual-targeting strategy to incorporate tumor-tropic MSC delivery with HER2-specific killing by the immunoapoptotin e23sFv-Fdt-tBid generated in our previous studies. The MSC engineering allowed simultaneous immunoapoptotin secretion and bioluminescence detection of the modified MSCs. Systemic administration of the immunoapoptotin-engineered MSCs was investigated in human HER2-reconstituted syngeneic mouse models of orthotopic and metastatic breast cancer, as well as in a xenograft nude mouse model of orthotopic gastric cancer. In vivo dual tumor targeting was confirmed by local accumulation of the bioluminescence-imaged MSCs and persistence of His-immunostained immunoapoptotins in tumor sites. The added tumor preference of MSC-secreted immunoapoptotins resulted in a significantly stronger antitumor effect compared with purified immunoapoptotins and Jurkat-delivered immunoapoptotins. This immunoapoptotin-armored MSC strategy provides a rationale for its use in extended malignancies by combining MSC mobility with redirected immunoapoptotins against a given tumor antigen.

Copper-catalyzed aminotrifluoromethylation of unactivated alkenes with (TMS)CF3: construction of trifluoromethylated azaheterocycles.

The first example of a copper(I)-catalyzed intramolecular aminotrifluoromethylation of unactivated alkenes using (TMS)CF3 (trimethyl(trifluoromethyl)silane) as the CF3 source is described. A broad range of electronically and structurally varied substrates undergo convenient and step-economical transformations for the concurrent construction of a five- or six-membered ring and a C-CF3 bond toward different types of trifluoromethyl azaheterocycles. The methodology not only circumvents use of expensive electrophilic CF3 reagents or the photoredox strategy but also expands the scope to substrates that are difficult to access by the existing methods. Mechanistic studies are conducted, and a plausible mechanism is proposed.