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Ammonia borane (AB) is considered to be a promising solid hydrogen carrier. In this work, poly(N-vinyl-2-pyrrolidone) (PVP)-protected platinum nanoparticles are supported on γ-methacryloxypropyltrimethoxysilane (γ-MPS) modified silica spheres (Pt-PVP/SiO 2 (M)), which are firstly used as highly efficient catalysts for hydrolysis of AB. Platinum nanoparticles possess a tiny size of 2–3 nm and are uniformly dispersed over modified silica spheres. Pt-PVP/SiO 2 (M) catalysts with a Pt loading amount of 1.30 wt% show the highest catalytic activity with a turnover frequency (TOF) value of 371 mol H2 mol Pt −1 min−1 (866 mol H2 mol Pt −1 min−1 corrected for the surface atoms) at 25 °C. The activation energy is calculated to be 46.2 kJ/mol. Furthermore, owing to the synergistic effect between the modifier of silica spheres and the capping agent of metal nanoparticles, Pt-PVP/SiO 2 (M) catalysts have a higher loading amount (8.7 and 6.5 times) and TOF value (4.8 and 5.5 times) than the counterparts prepared without γ-MPS and PVP, respectively. [Display omitted] • PVP-protected Pt nanoparticles were uniformly dispersed on modified SiO 2 spheres. • This catalyst showed superior catalytic activity for hydrolysis of ammonia borane. • The highest TOF value of 371 mol H 2 mol Pt−1 min−1 at 25 °C was achieved. • The synergistic effect between the PVP and the modifier of silica was studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermosensitive pseudohomogeneous catalysts (Pt, Pd, and Au) are synthesized. • Thermoresponsive PNIPAM polymer serves as the capping agent. • These catalysts show superior catalytic activity for reduction of nitroarenes. • PNIPAM-Pd can realize the homogenous reaction and heterogeneous separation. The reduction of nitroarenes is usually catalyzed by heterogeneous catalysts. In this work, highly stable aqueous dispersions of monodisperse Pt, Pd, and Au nanoparticles stabilized by thermosensitive polymer, poly(N-isopropylacrylamide) (PNIPAM), are conveniently synthesized with the average sizes of 2.3, 3.1, and 2.3 nm, respectively. The modulation of the hydrophilic-hydrophobic nano-environments of the catalysts can be selectively provided by utilizing the temperature-responsive characteristics of PNIPAM. They are effective and thermosensitive pseudohomogeneous catalysts for nitroarenes reduction. The decreasing trend of catalytic activity is as follows: PNIPAM-Au > PNIPAM-Pd > PNIPAM-Pt. The catalytic reduction of nitrobenzene (NB), 4-nitrophenol (4-NP), and o-nitroaniline (o-NA) follow the pseudo-first-order kinetics, and the catalytic rates can be tuned by utilizing their temperature-responsive behavior. PNIPAM-Au nanocatalysts exhibit high turnover frequencies (TOF) up to 84, 12.9, and 40 min−1 for catalytic reduction of NB, 4-NP, and o-NA at 20 °C, respectively, which are one of the highest values ever reported. [ABSTRACT FROM AUTHOR]

• The highly stable dispersions of ultrasmall ZnO nanocrystals were prepared. • They were used as pseudohomogeneous catalyst for chemical depolymerization of PET. • ZnO nanodispersions displayed an excellent catalytic activity at 170 °C. • The methanolysis had shorter reaction time and higher activity than the glycolysis. Chemical depolymerization and recycling of polyethylene terephthalate (PET) is a sustainable way to preserve the resources and protect the environment. In this work, methanol and ethylene glycol dispersions of ultrasmall ZnO nanoparticles are firstly adopted as pseudohomogeneous catalysts for alcoholysis of PET. The as-prepared ZnO nanoparticles have a uniform size of 4 nm and can be stable in dispersions for 6 months. In the methanolysis process of PET, the effects of various parameters on the conversion of PET and the yield of dimethyl terephthalate (DMT) were investigated. The results show that higher temperature (170 °C) was beneficial to the conversion of PET and the yield of DMT, which can reach about 97% and 95% after 15 min, respectively. The excellent activity of 553 g PET h−1 (g ZnO)−1 was achieved. Furthermore, the methanolysis of PET have shorter reaction time (1/4) and higher activity (4.7 times) than the glycolysis of PET. [ABSTRACT FROM AUTHOR]

• Size-tunable monodisperse Pd nanocrystals were prepared in a rotating packed bed. • They were adopted as pseudohomogeneous catalyst for nitrobenzene (NB) reduction. • 2.6 nm Pd nanocrystals displayed excellent catalytic property and good stability. • The obtained catalytic kinetics data confirm to the Langmuir-Hinshelwood model well. • DFT calculation was used to study the adsorption of NB on the surface of catalyst. Nitrobenzene (NB) reduction is an important catalytic reaction, which is commonly performed in aqueous medium mainly with heterogeneous catalysts. In this work, highly stable aqueous nanodispersions of Pd nanocrystals with a tunable average size between 2 and 11 nm are conveniently prepared in a high-gravity rotating packed bed (RPB) reactor, and firstly serve as a pseudohomogeneous catalyst for NB reduction. As compared to a conventional stirred tank reactor (STR), the product prepared in the RPB reactor has a more uniform particle size. More importantly, the reaction time can be greatly shortened from 3 min (STR) to 1 s (RPB), thereby realizing a continuous preparation. This Pd pseudohomogeneous catalyst displays a significantly size-dependent catalytic activity and a good stability performance. Ultra-small 2.6 nm Pd nanocrystals have a reaction rate five times as fast as 10.1 nm counterpart. The obtained kinetics data confirm to the Langmuir-Hinshelwood model well, having a small error of <10%. Furthermore, the adsorption behavior of NB molecules on the surface of Pd nanocrystals was also studied with density functional theory (DFT) calculation. Since the processing capacity of the used lab-scale RPB reached 44.2 g/h, this route may offer a general platform for mass production of monodisperse nanocrystals as pseudohomogeneous catalyst for highly efficient catalysis. [ABSTRACT FROM AUTHOR]

Background: Many blood markers have been shown to predict the recurrence and survival of various malignancies, but the effects of surgery on the body's inflammatory levels may cause changes in these inflammatory markers. Therefore, in this study, we assessed the relationship between changes in platelet to lymphocyte ratio (PLR) and survival and recurrence in patients with T3-T4 laryngeal squamous cell carcinoma (LSCC). Methods: Data of patients with T3-T4 HSCC were reviewed. Continuous variables were expressed as mean ± SD and were compared using t test or Mann-Whitney U test. The covariate distributions were compared by Chi-square test. Survival curve was estimated by Kaplan-Meier analysis, and Log-Rank test were performed to estimate the survival curve and significance of the difference in survival distribution between groups, respectively. The prognostic value was uncovered by univariate and multivariate Cox hazards analysis. Results: The 413 consecutive patients with LSCC were reviewed. Of these, 362 patients who met the criteria were selected, multi-factor analysis found that pathological T classification(hazard ratio [HR] = 1.878; 95% confidence interval [CI] = 1.342–3.023; P<0.001), pathological N classification (HR = 1.212; 95% CI = 0.867–2.125; P< 0.001) and change of PLR (HR = 2.158; 95% CI = 1.332–2.889; P = 0.004) associated with postoperative recurrence of T3-T4 LSCC. In addition, the pathological T classification (HR = 1.901; 95% CI = 1.255–2.999; P<0.001), pathological N classification (HR = 1.244; 95% CI = 0.810–2.212; P<0.001) and change of PLR (HR = 2.011; 95% CI = 1.354–2.753; P = 0.001) associated with postoperative survival in patients with T3-T4 LSCC. Conclusions: Results demonstrate that change in PLR may serve as a useful prognostic predictor for patients with T3-T4 LSCC. [ABSTRACT FROM AUTHOR]

The acellular dermal matrix (ADM) and turbinate flap (TF) have been widely used in the reconstruction of skull base defects. However, owing to the lack of reported data, the therapeutic effects have been controversial. The purpose of the present study was to compare the effect of the ADM and TF on cerebrospinal fluid (CSF) rhinorrhea after nasal endoscopic resection of a skull base tumor. The data from 46 patients who had undergone nasal endoscopic resection of a skull base tumor and repair of CSF rhinorrhea were retrospectively analyzed. The patients were divided into ADM and TF groups according to the difference in repair materials used. We compared and analyzed the intraoperative information and postoperative outcomes. The operation time, blood loss, defect area, and need for blood transfusion were not significantly different between the ALT and TF groups. The postoperative length of hospital stay (14.33 ± 3.66 vs. 16.76 ± 5.51 days; P = 0.669) and the incidence of complications, including wound infection (1 vs. 0; P = 0.270), intracranial infection (1 vs. 1; P = 0.900), hemorrhage (2 vs. 3; P = 0.788), 15-day CSF leak (1 vs. 2; P = 0.658), and respiratory infection (2 vs. 1; P = 0.450) were comparable between the 2 groups. The 6-month (0 vs. 0; P = 1.000) and 12-month (0 vs. 0; P = 1.000) incidence of recurrence also showed no significant differences. The use of the ADM for patients with CSF rhinorrhea showed comparable results in terms of postoperative outcomes compared with the use of TF. ADM could serve as a safe and feasible alternative for endoscopic repair of CSF rhinorrhea after nasal endoscopic resection of skull base tumors. [ABSTRACT FROM AUTHOR]

Background: The discomfort and complications have always been problems for nasal packing materials. This study provided a new nasal packing material called high expansion degradable cotton (HEDC). Methods: Nasal endoscopic surgery was used to establish a dog model of nasal bleeding, and wound surfaces were filled with Merocel, Nasopore and HEDC, respectively. Intraoperative and postoperative bleeding of 24 h was calculated. We evaluate the absorbability score, adhesion score, infection sore and nasal mucosal epithelium in postoperative 3, 7, 14 and 28 days. HE staining and electron microscopy were used to evaluate the recovery of nasal mucosa. Results: There was no significant difference in nasal bleeding between HEDC, Merocel and Nasopore. Nasal endoscopic examination revealed HEDC absorbability of score, adhesion score, infection score were significantly lower than Merocel and Nasopore. The epithelialization time of HEDC was significantly shorter than that of Merocel and Nasopore. HE staining showed that HEDC and Nasopore could significantly reduce scar hyperplasia on the wound surface. The results of electron microscopy suggested that HEDC could protect the edge cilia of the wound. Conclusion: HEDC could be used as new choice for hemostasis after nasal endoscopic surgery, which could reduce nasal epithelialization time, and protect wound edge cilia. [ABSTRACT FROM AUTHOR]

Background Nasal endoscopic surgery is widely used for nasal diseases, including sinusitis and tumors. However, scar hyperplasia, nasal irritation, scab, and nasal obstruction delay nasal mucosal recovery, with prolonged cleaning exacerbating the patient's financial burden. Here, we presented a novel approach for the treatment of nasal mucosal defects, termed acellular dermal matrix. Methods A total of 31 patients with bilateral chronic sinusitis (maxillary sinusitis and ethmoid sinusitis) underwent nasal surgery and nasal mucosal repair in September–October 2016. We divided the nasal cavities of each patient into control and acellular dermal matrix groups, randomly selected one side for nasal mucosal repair by surgery. A suitable acellular dermal matrix size was selected according to the defect in each patient. After pruning, the acellular dermal matrix was placed on the wound surface and filled with gelatin sponge. All patients were followed up for 14 weeks to compare nasal mucosal epithelialization between the control and acellular dermal matrix groups. Results：No obvious complications and adverse reactions were observed after nasal surgery. Lund-Kennedy scores in the acellular dermal matrix group were significantly decreased compared with the control group at 8 (0 (0, 1) vs. 2 (2, 4); P<0.05) weeks. Epithelialization time of eight weeks in the acellular dermal matrix groups was significantly decreased than the control group of 14 weeks. Conclusion Acellular dermal matrix provides a growth framework for the healthy mucosa on the wounded surface and reduces postoperative epithelialization time. [ABSTRACT FROM AUTHOR]

The association between neutrophil-to-lymphocyte ratio (NLR) and differentiated thyroid cancer (DTC) is undecided. To rectify this question, we conducted a systematic meta-analysis based on 7 prospective cohort studies published between 2013 and 2015, comprising 7349 patients. Six of these cohorts included pretreatment (baseline) NLR data for patients with thyroid nodules. The meta-analysis of these 6 cohorts showed that the NLR of patients with DTC (4617 cases) was statistically similar to patients with benign nodules only (1666 cases), with a mean difference (MD) of 0.19 (95% CI: −0.09 to 0.46; I2 = 93%; P < 0.001). No significant difference in NLR was found between patients with DTC and patients with benign nodules. Two studies addressed an association between NLR and papillary thyroid carcinoma in patients stratified by age <45 and ≥45 years (496 and 891 cases, respectively); the pooled MD was 0.09 (95% CI: −0.37 to 0.55; I2 = 92.2%, P < 0.001). An elevated NLR seems not a reliable indicator of progressing DTC in patients with goiters, and there was no difference in NLR between patients aged <45 years and those aged ≥45 years. Well-designed and large-scale investigations are warranted to understand the value of NLR in the prognosis of DTC. [ABSTRACT FROM AUTHOR]