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•Polyurethane from bio-derived epoxides by CO2 utilization via non-isocyanate route.•Co − Co metallic valance site was identified over Co − heteroatom site.•Influence of encapsulated ...enzyme in capacitance and CO2 cycloaddition-polymerization performance.•High-performance of Co sites are protected by multiwall shell architecture.
Enzyme encapsulated ZIFs exhibit significant host–guest synergism and protect the relative activity of the enzymes. Elucidation of metallic active sites including the nature of electronics and valance state has been forefront in energy conversion studies supported by high-resolution transmission electron microscopy and synchrotron X-ray absorption fine structure (XAFS) spectrogram. Here, we access metallic cobalt (Co) sites that were set by pyrolysis of catalase encapsulated ZIF-67 (cat@ZIF-67) at a high temperature (700 °C) to obtain cat@ZIF-67-NC. The local environment of Co-sites from X-ray photoelectron spectroscopic (XPS) and extended X-ray absorption fine structure (EXAFS) analysis suggests the presence of Co sites in a metallic valance state. HR-TEM and STEM analysis further revealed the Co particles encapsulated with multiwall shell morphology as support. An activity reversal is witnessed, where cat@ZIF-67-NC exhibited higher activity in CO2-cycloaddition-polymerization but was found weaker in capacitance than ZIF-67-NC for 3-electrode supercapacitor applications. The ZIF-67-NC has exhibited maximum Cs of 223 F/g at a scan rate of 5 mV/s, which retained about 87 F/g on increasing scan rate to 200 mV/s, in contrast to cat@ZIF-67-NC with a Cs value of 133.4 F/g at 5 mV/s with improved retention (58 % at 200 mV/s). The contrasting nature of cat-ZIF-67-NC and ZIF-67-NC in supercapacitor and CO2 cycloaddition-polymerization originates from encapsulated catalase in ZIF-67 based on XPS and EXAFS analysis. The electronic configuration and surface composition analysis using EXAFS and XPS techniques revealed the presence of metallic Co-sites responsible for supercapacitor and CO2-cycloaddition-polymerization. An influence of encapsulated catalase is evident in a decrease in the capacitance for cat@ZIF-67-NC due to metallic Co-sites. Co-sites in cat-ZIF-67-NC are more active in producing polyurethane by a non-isocyanate route via CO2-cycloaddition.
Bladder cancer (BC) is the second most common urologic malignancy and the ninth most common malignancy worldwide. Surgical resection is the mainstay of treatment for patients with early-stage ...disease, whereas therapeutic options are limited for patients with advanced-stage or residual BC. Programmed cell death ligand-1 (PD-L1) is an important target for immunotherapy. It is known that PD-L1 is overexpressed in BC; a clinical trial involving PD-L1 immune checkpoint inhibitors in advanced BC is ongoing. In the present study, we used Western blot and quantitative real-time PCR (qPCR) to define the expression level of PD-L1 after cisplatin treatment in BC-derived cell lines. The signal activation was also evaluated by Western blot in BC-derived cell lines. We found that chemotherapeutic drug cisplatin can induce PD-L1 but not PD-L2 expression in BC-derived cell lines. Furthermore, the expression level of PD-L1 was increased in a dose- and time-dependent manner after cisplatin treatment. The cisplatin-induced PD-L1 expression is mainly mediated by ERK1/2 but not Akt/mTOR signal pathway. Moreover, we found that cisplatin activates transcription factor activator protein-1 (AP-1) to regulate PD-L1 expression. The chemotherapy drug such as cisplatin may trigger resistance of BC through PD-L1 up-regulation. The present study suggests that PD-L1 antibody should be used concomitantly with chemotherapy in the setting of advanced and metastatic BC.
Carbon molecular sieve (CMS) membranes hold great promise for energy-efficient gas separation, contributing to mitigating greenhouse gas emissions. Exploring new types of microstructurally tunable ...polymeric precursors is critical for understanding the evolution of carbon microstructure arrangement and adjusting the gas permeation behavior of CMS membranes. As a precursor for CMS membranes, polyphthalonitrile (PPN) resin with both tunable intermolecular distance and π-π stacking arrangement is reported for the first time. We have demonstrated that the aforementioned two key features of the thermally crosslinked PPN network are beneficial to forming PPN-CMS membranes with enlarged intermolecular distance and small-sized, narrow-distributed ultramicropores (<7 Å), thereby improving gas permeability and ideal selectivity. This study provides new insights into the microstructure evolution of PPN-derived microporous carbon materials. Owing to its excellent thermal stability, tunable microstructure arrangement, and flexibility of chemical synthesis, PPN represents a promising class of polymeric precursor materials for fabricating CMS membranes.
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•Polyphthalonitrile (PPN) as new precursor for carbon molecular sieve (CMS) membrane.•Evolution of microstructure arrangement of PPN-derived carbon was elucidated.•Crosslinking of PPN expands intermolecular distance of CMS, improving permeability.•π-π stacking of PPN forms small, narrow ultramicropore of CMS, raising selectivity.
Low-grade, or Spetzler-Martin (SM) Grades I and II, arteriovenous malformations (AVMs) are associated with lower surgical morbidity rates than higher-grade lesions. While radiosurgery is now widely ...accepted as an effective treatment approach for AVMs, the risks and benefits of the procedure for low-grade AVMs, as compared with microsurgery, remain poorly understood. The authors of this study present the outcomes for a large cohort of low-grade AVMs treated with radiosurgery.
From an institutional radiosurgery database comprising approximately 1450 AVM cases, all patients with SM Grade I and II lesions were identified. Patients with less than 2 years of radiological follow-up, except those with complete AVM obliteration, were excluded from analysis. Univariate and multivariate Cox proportional-hazards and logistic regression analyses were used to determine factors associated with obliteration, radiation-induced changes (RICs), and hemorrhage following radiosurgery.
Five hundred two patients harboring low-grade AVMs were eligible for analysis. The median age was 35 years, 50% of patients were male, and the most common presentation was hemorrhage (47%). The median AVM volume and prescription dose were 2.4 cm(3) and 23 Gy, respectively. The median radiological and clinical follow-up intervals were 48 and 62 months, respectively. The cumulative obliteration rate was 76%. The median time to obliteration was 40 months, and the actuarial obliteration rates were 66% and 80% at 5 and 10 years, respectively. Independent predictors of obliteration were no preradiosurgery embolization (p < 0.001), decreased AVM volume (p = 0.005), single draining vein (p = 0.013), lower radiosurgery-based AVM scale score (p = 0.016), and lower Virginia Radiosurgery AVM Scale (Virginia RAS) score (p = 0.001). The annual postradiosurgery hemorrhage rate was 1.4% with increased AVM volume (p = 0.034) and lower prescription dose (p = 0.006) as independent predictors. Symptomatic and permanent RICs were observed in 8.2% and 1.4% of patients, respectively. No preradiosurgery hemorrhage (p = 0.011), a decreased prescription dose (p = 0.038), and a higher Virginia RAS score (p = 0.001) were independently associated with postradiosurgery RICs.
Spetzler-Martin Grade I and II AVMs are very amenable to successful treatment with stereotactic radiosurgery. While patient, physician, and institutional preferences frequently dictate the final course of treatment, radiosurgery offers a favorable risk-to-benefit profile for the management of low-grade AVMs.
Background: Diabetes is known to impair wound healing and deteriorate the periodontal condition. There is limited information about the patterns and events associated with periodontal wound repair. ...In this study, we evaluate the dynamics of periodontal wound repair using micro‐computed tomography (microCT) and immunohistochemistry.
Methods: Thirty‐six male rats were used, and diabetes was induced by streptozotocin. The maxillary first molars were extracted, and a tooth‐associated osseous defect was created in the extraction area. Animals were sacrificed after 7, 14, and 21 days. Volumetry and distribution of bone trabeculae were evaluated by microCT imaging. The patterns of healing and collagen alignment were evaluated by histology. Advanced glycation end‐product (AGE) deposition and expression of the receptor for AGEs (RAGE), tartrate‐resistant acid phosphatase, and proliferating cell nuclear antigen were evaluated by histochemical and immunohistochemical staining.
Results: Diabetic animals demonstrated a significantly reduced bone volume and trabecular number as well as thinner trabeculae and more trabecular separation in osseous defects. The early stage was characterized by significantly reduced cellular proliferation and prolonged active inflammation without evident bone resorption, whereas delayed recovery of collagen realignment, matrix deposition, and bone turnover was noted in later stages. Although AGEs and RAGE were present during healing in diabetes and controls, a stronger and more persistent level of expression was observed in the group with diabetes
Conclusions: Diabetes significantly delayed osseous defect healing by augmenting inflammation, impairing proliferation, and delaying bone resorption. The AGE–RAGE axis can be activated under metabolic disturbance and inflammation.
The aim in this paper was to compare the outcomes of dose-staged and volume-staged stereotactic radio-surgery (SRS) in the treatment of large (> 10 cm(3)) arteriovenous malformations (AVMs).
A ...systematic literature review was performed using PubMed. Studies written in the English language with at least 5 patients harboring large (> 10 cm(3)) AVMs treated with dose- or volume-staged SRS that reported post-treatment outcomes data were selected for review. Demographic information, radiosurgical treatment parameters, and post-SRS outcomes and complications were analyzed for each of these studies.
The mean complete obliteration rates for the dose- and volume-staged groups were 22.8% and 47.5%, respectively. Complete obliteration was demonstrated in 30 of 161 (18.6%) and 59 of 120 (49.2%) patients in the dose- and volume-staged groups, respectively. The mean rates of symptomatic radiation-induced changes were 13.5% and 13.6% in dose- and volume-staged groups, respectively. The mean rates of cumulative post-SRS latency period hemorrhage were 12.3% and 17.8% in the dose- and volume-staged groups, respectively. The mean rates of post-SRS mortality were 3.2% and 4.6% in dose- and volume-staged groups, respectively.
Volume-staged SRS affords higher obliteration rates and similar complication rates compared with dose-staged SRS. Thus, volume-staged SRS may be a superior approach for large AVMs that are not amenable to single-session SRS. Staged radiosurgery should be considered as an efficacious component of multimodality AVM management.
The increasing demand for hydrogen production has necessitated the development of H2-selective membranes. Polyimides are excellent membrane materials for gas separation; however, commercial ...polyimides generally lack sufficient H2 selectivity due to their low H2 affinity. Understanding the relationship between gas transport properties and free volume microstructure is critical to advancing H2-selective membrane design. Herein, we report a facile material strategy to adjust the free volume characteristics and H2 separation performance via blending Matrimid (PI) and crosslinkable resorcinol-based phthalonitrile prepolymer (RPN) with electron donor/acceptor properties. The novel RPN30/PI70 membrane exhibits H2/N2 and H2/CO2 permselectivity of 1637 and 66.4, respectively, with H2 permeability of 2.7 Barrer in pure gas test, surpassing Robeson upper bounds (2008). The increased H2 permselectivity of RPN/PI membranes was attributed to the narrowed free volume size and distribution, giving rise to the considerably improved H2 solubility and selectivity of the blends. Moreover, the H2 permeability of crosslinked RPN30/PI70 membranes can be further improved via thermal treatment. The H2/CO2 mixed-gas test reveals that the H2 gas separation performance of the RPN30/PI70 membrane is influenced by plasticization effect and competitive sorption. This study demonstrates a new versatile strategy for designing high-performance hydrogen-selective polymeric membranes.
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Bladder cancer (BC) is the second most common urological tumour in Western countries. Approximately, 80% of patients with BC will present with non-muscle invasive bladder cancer (NMIBC), whereas a ...quarter will have muscle invasive disease (MIBC) at the time of BC diagnosis. However, patients with NMIBC are at risk of BC recurrence or progression into MIBC, and an MIBC prognosis is determined by the presence of progression and metastasis. Matrix metalloproteinase 2 (MMP2), a type of matrix metalloproteinase (MMP), plays a major role in tumour invasion and is well-characterized in BC prognosis. In BC, the mechanisms regulating MMP2 expression, and, in turn, promote cancer invasion, have hardly been explored. Thrombospondin-4 (THBS4/TSP4) is a matricellular glycoprotein that regulates multiple biological functions, including proliferation, angiogenesis, cell adhesion and extracellular matrix modelling. Based on the results of a meta-analysis in the Gene Expression Profiling Interactive Analysis 2 database, we observed that TSP4 expression levels were consistent with overall survival (OS) rate and BC progression, with the highest expression levels observed in the advanced stages of BC and associated with poor OS rate. In our pilot experiments, incubation with recombinant TSP4 promoted the migration and invasion in BC cells. Furthermore, MMP2 expression levels increased after recombinant TSP4 incubation. TSP4-induced-MMP2 expression and cell motility were regulated via the AKT signalling pathway. Our findings facilitate further investigation into TSP4 silencing-based therapeutic strategies for BC.
Background. The efficacy of a thrombin-based hemostatic agent (Floseal®) on reducing postoperative blood loss after total knee arthroplasty (TKA) was still unclear. The aim of our study was to ...conduct a prospective randomized controlled study to compare the blood conservation effects of Floseal® and topical TXA in patients with preexisting thromboembolic risk undergoing primary minimally invasive TKA. Methods. Our power analysis of this study was based upon the following description, to obtain a statistical power of 0.90 and an alpha error of 0.05, 30 patients were required in each group. Therefore, we enrolled a total of 103 patients with at least one of the risk factors for thromboembolism who underwent unilateral primary minimally invasive TKA, and the participants were randomly divided into the topical TXA group (n=34), receiving intra-articular injection of 3 g of TXA in 100 mL saline after TKA, the topical Floseal® group (n=34), receiving 10 mL of Floseal® intra-articularily during surgery, and the placebo group (n=35), receiving an intra-articular saline injection only. The total blood loss (TBL) and hemoglobin (Hb) drop were compared among the 3 groups. Results. The TXA group had a lower TBL of 645 mL (227 to 1090) in comparison with 1145 mL (535 to 1942) in the Floseal® group and 1103 mL (424 to 1711) in the placebo (p<0.001, respectively). The TBL was similar between the Floseal® group and the placebo group (p=0.819). No patients in any group had symptoms of venous thromboemblism. Conclusion. Our prospective randomized controlled study showed that intra-articular application of TXA was superior to hemostatic matrix (Floseal®) in terms of blood conservation in patients with preexisting thromboembolic risk undergoing minimally invasive TKA. This trial is registered with Clinicaltrials.gov (NCT02865174) on 08/09/2016.
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