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1.
Mater Sci Eng C Mater Biol Appl ; 115: 111123, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32600722

RESUMO

Anti-inflammation and angiogenesis play an essential role in wound healing. In this study, we developed a composite hydrogel dressing with stepwise delivery of diclofenac sodium (DS) and basic fibroblast growth factor (bFGF) in the inflammation stage and new tissue formation stage respectively for wound repair. Sodium alginate (SA) crosslinked by calcium ion acted as the continuous phase, and thermosensitive bFGF-loaded poly(N-isopropylacrylamide) nanogels (pNIPAM NGs, LCST1 ~33 °C) and DS-loaded p(N-isopropylacrylamide-co-acrylic acid) nanogels [p(NIPAM-co-AA) NGs, LCST2 ~40 °C] acted as the dispersed phase. The synthesized SA/bFGF@pNIPAM/DS@p(NIPAM-co-AA) hydrogel presented a desirable storage modulus of ~4500 Pa, a high water equilibrium swelling ratio of ~90, an appropriate water vapor transmission rate of ~2300 g/m2/day, and nontoxicity to human skin fibroblasts. The in vitro thermosensitive cargo delivery of this hydrogel showed that 92% of DS was sustainably delivered at 37 °C within the early three days mimicking the inflammation stage, while 80% of bFGF was controlled released at 25 °C within the later eight days mimicking new tissue formation stage. The in vivo wound healing of rats showed that this composite hydrogel presented a better healing effect with a wound contraction of 96% at 14 d, less inflammation and higher angiogenesis, than all control groups. These findings indicate SA/bFGF@pNIPAM/DS@p(NIPAM-co-AA) composite hydrogel is a potential dressing for wound repair.

2.
JMIR Med Inform ; 8(6): e19202, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32584262

RESUMO

BACKGROUND: Before major emergencies occur, the government needs to prepare various emergency supplies in advance. To do this, it should consider the coordinated storage of different types of materials while ensuring that emergency materials are not missed or superfluous. OBJECTIVE: This paper aims to improve the dispatch and transportation efficiency of emergency materials under a model in which the government makes full use of Internet of Things technology and artificial intelligence technology. METHODS: The paper established a model for emergency material preparation and dispatch based on queueing theory and further established a workflow system for emergency material preparation, dispatch, and transportation based on a Petri net, resulting in a highly efficient emergency material preparation and dispatch simulation system framework. RESULTS: A decision support platform was designed to integrate all the algorithms and principles proposed. CONCLUSIONS: The resulting framework can effectively coordinate the workflow of emergency material preparation and dispatch, helping to shorten the total time of emergency material preparation, dispatch, and transportation.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32510925

RESUMO

Cesium (Cs) contained triple-cation and mixed halide perovskite (CsFAMA) is broadly employed as light absorption layers for efficient and stable perovskite solar cells (PSCs) fabrication with high reproducibility. On the other hand, thermal annealing is a universal post-treatment method for perovskite films preparation. Moreover, thermal management highly depends on perovskite materials. However, no specialized study has been reported on CsFAMA perovskite to date. Herein, we have systematically investigated the influence of thermal annealing and annealing time on CsFAMA films and their solar cells. We demonstrated that heating time of 45 or 60 min at 100 °C is desirable. More interestingly, we found that the unannealed CsFAMA films exhibit ultrahigh photoluminescence (PL) intensities, much stronger than that of annealed films. Note that PL intensities gradually weaken as a function of annealing time. In particular, the PL intensities of fresh films (after antisolvent dripping) are at least 200 times higher than that of 60 min annealed films. To our knowledge, it is the first time to report this PL behavior. We speculate that it is due to quantum confinement effect of perovskite crystal nuclei and "cage effect" of DMSO intermediates in the fresh films. To this point, the unannealed CsFAMA films may have great potential in PL emission applications.

4.
J Environ Sci (China) ; 92: 151-162, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32430118

RESUMO

Methylglyoxal (CH3COCHO, MG), which is one of the most abundant α-dicarbonyl compounds in the atmosphere, has been reported as a major source of secondary organic aerosol (SOA). In this work, the reaction of MG with hydroxyl radicals was studied in a 500 L smog chamber at (293 ± 3) K, atmospheric pressure, (18 ± 2)% relative humidity, and under different NOx and SO2. Particle size distribution was measured by using a scanning mobility particle sizer (SMPS) and the results showed that the addition of SO2 can promote SOA formation, while different NOx concentrations have different influences on SOA production. High NOx suppressed the SOA formation, whereas the particle mass concentration, particle number concentration and particle geometric mean diameter increased with the increasing NOx concentration at low NOx concentration in the presence of SO2. In addition, the products of the OH-initiated oxidation of MG and the functional groups of the particle phase in the MG/OH/SO2 and MG/OH/NOx/SO2 reaction systems were detected by gas chromatography mass spectrometry (GC-MS) and attenuated total reflection fourier transformed infrared spectroscopy (ATR-FTIR) analysis. Two products, glyoxylic acid and oxalic acid, were detected by GC-MS. The mechanism of the reaction of MG and OH radicals that follows two main pathways, H atom abstraction and hydration, is proposed. Evidence is provided for the formation of organic nitrates and organic sulfate in particle phase from IR spectra. Incorporation of NOx and SO2 influence suggested that SOA formation from anthropogenic hydrocarbons may be more efficient in polluted environment.

5.
J Biomol Struct Dyn ; : 1-12, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32425109

RESUMO

Phosphatidylinositol 3-kinase alpha (PI3Kα) is among the most important PI3K isoforms and has been associated with multiple human cancers. Therefore, PI3Kα has garnered considerable attention as a viable target for anticancer drug discovery, and thus the identification and development of highly potent inhibitors of this isoform has become an important line of research. Here, structure-based virtual screening, bioassays, and molecular dynamics simulations were performed to discover novel potential PI3Kα inhibitors. TCM-N1 (ZINC13382850) was identified as a possible PI3Kα inhibitor. Particularly, fluorescence quenching assays determined that the binding affinity of the aforementioned compound was superior to that of a reference ligand (BYL719; i.e. a known PI3Kα inhibitor). Moreover, enzymatic activity and cell proliferation inhibition assays indicated that TCM-N1 possessed a moderate inhibition activity against PI3Kα and a relatively high anti-tumor proliferation ability in gastric, colorectal, and cervical cancer cells. The binding model and related thermodynamic parameters further demonstrated that TCM-N1 was tightly embedded into the ATP-binding pocket via hydrogen bonds, van der Waals interactions, and hydrophobic interactions. Therefore, this study provides promising insights into the development and design of more potent PI3Kα-inhibiting analogs. Communicated by Ramaswamy H. Sarma.

6.
J Wound Ostomy Continence Nurs ; 47(3): 215-223, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32384524

RESUMO

PURPOSE: The purpose of this systematic review and quantitative analysis of pooled data was to assess the global incidence of pressure injury (PI), across time frames and countries, in individuals with spinal cord injury (SCI). DESIGN: Systematic review and meta-analysis. SEARCH STRATEGY: PubMed, Web of Science, and EMBASE databases were systematically searched for studies published from database inception to January 2019, with only English language studies that reported the incidence of PIs in individuals with SCI were included. Study quality was assessed by a 14-item standardized checklist. We calculated the incidence of PIs as the number of new PIs in individuals with SCI and the total number of individuals with SCI during the study period. Findings are presented as incidence rate with 95% confidence intervals (CIs). RESULTS: The search yielded 1652 studies; after studies were reviewed for inclusion criteria, 29 studies representing N = 82,722 patients were retained for data extraction. The global incidence of PIs was 0.23 (95% CI, 0.20-0.26). Data for regional distribution by country showed a pooled incidence of 0.43 (95% CI, 0.28-0.57) in individuals with SCI in South American countries, 0.36 (95% CI, 0.16-0.56) in African countries, 0.25 (95% CI, 0.14-0.37) in European countries, 0.23 (95% CI, 0.19-0.27) in North American countries, and 0.16 (95% CI, 0.06-0.25) in Asian countries. The incidence was 0.22 (95% CI, 0.19-0.26) in developing countries versus 0.27 (95% CI, 0.17-0.37) in developed countries. From 2000 to 2009, the incidence of PIs in individuals with SCI was 0.28 (95% CI, 0.09-0.47). The incidence rate of PIs before 2000 and after 2009 was 0.23. The hospital- and community-acquired PI incidence was 0.22 (95% CI, 0.19-0.26) and 0.26 (95% CI, 0.20-0.32), respectively. CONCLUSIONS: Study findings indicate that more than 1 in 5 individuals with SCI will develop a PI. Individuals with SCI are at high risk of developing PI, especially in community settings or low- and middle-income developing countries. The findings highlight the importance of further investigation of risk factors and prevention and management strategies for PIs in individuals with SCI.

7.
Sensors (Basel) ; 20(9)2020 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-32357470

RESUMO

Leaf area index (LAI) is an important biophysical parameter, which can be effectively applied in the estimation of vegetation growth status. At present, amounts of studies just focused on the LAI estimation of a single plant type, while plant types are usually mixed rather than single distribution. In this study, the suitability of GF-1 data for multi-species LAI estimation was evaluated by using Gaussian process regression (GPR), and a look-up table (LUT) combined with a PROSAIL radiative transfer model. Then, the performance of the LUT and GPR for multi-species LAI estimation was analyzed in term of 15 different band combinations and 10 published vegetation indices (VIs). Lastly, the effect of the different band combinations and published VIs on the accuracy of LAI estimation was discussed. The results indicated that GF-1 data exhibited a good potential for multi-species LAI retrieval. Then, GPR exhibited better performance than that of LUT for multi-species LAI estimation. What is more, modified soil adjusted vegetation index (MSAVI) was selected based on the GPR algorithm for multi-species LAI estimation with a lower root mean squared error (RMSE = 0.6448 m2/m2) compared to other band combinations and VIs. Then, this study can provide guidance for multi-species LAI estimation.

8.
Chemosphere ; 253: 126743, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32464777

RESUMO

In coastal regions, intense bursts of particles are frequently observed with high concentrations of iodine species, especially iodic acid (IA). However, the nucleation mechanisms of IA, especially in polluted environments with high concentrations of sulfuric acid (SA) and ammonia (A), remain to be fully established. By quantum chemical calculations and atmospheric cluster dynamics code (ACDC) simulations, the self-nucleation of IA in clean coastal regions and that influenced by SA and A in polluted coastal regions are investigated. The results indicate that IA can form stable clusters stabilized by halogen bonds and hydrogen bonds through sequential addition of IA, and the self-nucleation of IA can instantly produce large amounts of stable clusters when the concentration of IA is high during low tide, which is consistent with the observation that intense particle bursts were linked to high concentrations of IA in clean coastal regions. Besides, SA and A can stabilize IA clusters by the formation of more halogen bonds and hydrogen bonds as well as proton transfers, and the binary nucleation of IA-SA/A rather than the self-nucleation of IA appears to be the dominant pathways in polluted coastal regions, especially in winter. These new insights are helpful to understand the mechanisms of new particle formation induced by IA in clean and polluted coastal regions.

9.
Ultrasound Med Biol ; 46(8): 1916-1927, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32451191

RESUMO

The purpose of this multicenter study was to compare the differential diagnostic value of the 2015 American Thyroid Association (ATA) and 2017 American College of Radiology (ACR) practice guidelines and elastography in thyroid nodules. This study also investigated whether the diagnostic value of practice guidelines can be improved, and the unnecessary biopsy rate decreased in combination with elastography. A total of 498 thyroid nodules were evaluated using the ATA and the ACR guidelines. Strain elastography, acoustic radiation force impulse imaging and point-shear wave elastography were used to assess the nodules. The suspicious levels were downgraded or upgraded after combination and unnecessary biopsy rates were calculated, respectively. The diagnostic performance of the practice guidelines was better than that of elastography. The ACR guidelines had a lower unnecessary biopsy rate and similar diagnostic performance compared with the ATA guidelines. The unnecessary biopsy rates significantly decreased when the ACR guidelines were combined with elastography, but the rates did not decrease when the ATA guidelines were combined with elastography.

10.
Environ Pollut ; 264: 114742, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32402708

RESUMO

1,3,5-Trimethylbeneze (TMB) is an important constituent of anthropogenic volatile organic compounds that contributes to the formation of secondary organic aerosol (SOA). A series of chamber experiments were performed to probe the effects of NOx and SO2 on SOA formation from TMB photooxidation. The molecular composition of TMB SOA was investigated by ultra-high performance liquid chromatography/electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-Q-TOFMS). We found that the SOA yield increases notably with elevated NOx concentrations under low-NOx condition ([TMB]0/[NOx]0 > 10 ppbC ppb-1), while an opposite trend is observed in high-NOx experiments ([TMB]0/[NOx]0 < 10 ppbC ppb-1). The increase in SOA yield in low-NOx regime is attributed to the increase of NOx-induced OH concentrations. The formation of low-volatility species might be suppressed, thereby leading to a lower SOA yield in high-NOx conditions. Moreover, SOA formation was promoted in experiment with SO2 addition. Multifunctional products containing carbonyl, acid, alcohol, and nitrate functional groups were characterized in TMB/NOx photooxidation, whereas several organosulfates (OSs) and nitrooxy organosulfates were identified in TMB/NOx/SO2 photooxidation based on HR-Q-TOFMS analysis. The formation mechanism relevant to the detected compounds in SOA were proposed. Based on our measurements, the photooxidation of TMB in the presence of SO2 may be a new source of OSs in the atmosphere. The results presented here also deepen the understanding of SOA formation under relatively complex polluted environments.

11.
Cell Cycle ; 19(13): 1632-1640, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32436804

RESUMO

In recent years, studies have revealed HOXA2 as a new oncogene, but its function is unknown in gliomas. We aimed to reveal the relationship between HOXA2 and glioma based on the Chinese Glioma Genome Atlas(CGGA) and the cancer genome atlas (TCGA). HOXA2 expression data and clinically relevant information of glioma patients were obtained from the CGGA and TCGA containing 1447 glioma tissues and five non-tumor brain tissues. The Wilcox or Kruskal tests were used to detect the correlation between the HOXA2 expression level and clinical data of glioma patients. the Kaplan-Meier method were used to examine the relationship between HOXA2 and overall patient survival. Gene set enrichment analysis (GSEA) was conducted to indirectly reveal the signaling pathways involved in HOXA2, and RT-PCR was used to detect HOXA2 expression in gliomas and non-tumor brain tissues. High HOXA2 expression was found to be positively correlated with clinical grade, histological type, age, and tumor recurrence, but negatively correlated with 1p19 codeletion and isocitrate dehydrogenase mutation status.RT-PCR results showed that HOXA2 expression levels were significantly higher in tumor tissues than in non-tumor brain tissues. GSEA showed that HOXA2 promoted the activation of the activation of the JAK-STAT-signaling pathway, focal adhesion, cell-adhesion-molecules-CAMS pathway, cytosolic DNA sensing pathway, and natural killer cell-mediated cytotoxicity. This study revealed for the first time that the novel oncogene,HOXA2, leads to poor prognosis in gliomas, and can be used as a biomarker for the diagnosis and treatment of gliomas.

12.
Acta Biomater ; 110: 105-118, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32339710

RESUMO

A series of poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogels containing cross-linked ß-cyclodextrin-hyaluronan (ß-CD-crHA), with tear protein adsorption resistance and sustained drug delivery, were developed as contact lens materials for eye diseases. ß-CD-HA was synthesized from aminated ß-CD and HA and then crosslinked within pHEMA hydrogel using polyethylenimine as a crosslinker. The synthesized ß-CD-HA was characterized by 1H NMR analysis, and ß-CD-crHA immobilized in pHEMA hydrogel was confirmed by FT-IR, SEM, and AFM analyses. The incorporation of ß-CD-crHA significantly improved the surface hydrophilicity, water uptake ability, oxygen permeability, and flexibility of pHEMA hydrogel, but did not compromise light transmission. pHEMA/ß-CD-crHA hydrogels not only decreased the tear protein adsorption because of the electrostatically mutual repulsion and the improved hydrophilicity, leading to the reduced adhesion of Staphylococcus aureus on the hydrogel surface, but also enhanced the encapsulation capacity and the sustainable delivery of diclofenac due to the formation of inclusion complexes between ß-CD and drugs. All the hydrogels were nontoxic to 3T3 mouse fibroblasts by in vitro cell viability analysis. Among these hydrogels with different ß-CD-crHA contents, pHEMA/ß-CD-crHA10 hydrogel showed the lowest water contact angle of 52 °, the highest water content of 65%, the largest Dk value of 36.4 barrer, and the optimal modulus of 1.8 MPa, as well as a good light transmission of over 90%. The in vivo conjunctivitis treatment of rabbits for 72 h indicated that drug-loaded pHEMA/ß-CD-crHA10 hydrogel presented a better therapeutic effect than both one dose administration of drug solution per day and drug-loaded pHEMA hydrogel. Thus, pHEMA/ß-CD-crHA10 hydrogel is a promising contact lens material for ophthalmic diseases. STATEMENT OF SIGNIFICANCE: Topical eye drops are currently the most popular treatment for ophthalmic diseases, but frequent dosing is necessary to acquire the desirable clinical effect at the expense of systemic side-effects. Drug-loaded contact lenses, as an alternative of eye drops, possess many good performances and show potential applications. However, the sustained drug delivery and the tear protein adsorption resistance are still challenging for contact lenses. Hence, we developed a novel pHEMA/ß-CD-crHA hydrogel by incorporating ß-CD-crHA crosslinked network into pHEMA hydrogel. Besides the improvements in surface hydrophilicity, water uptake ability, oxygen permeability, and flexibility, pHEMA/ß-CD-crHA hydrogel also reduced the adsorption of tear proteins and the adhesion of Staphylococcus aureus, enhanced the drug encapsulation, and prolonged the drug delivery, with better effect in the conjunctivitis treatment of rabbits. Thus, pHEMA/ß-CD-crHA hydrogel is a potential contact lens material for treating ophthalmic diseases.

13.
Nutr Clin Pract ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32166790

RESUMO

The aim of this systematic review was to summarize the evidence on the efficacy of zinc supplementation in patients with pressure injuries (PIs). Electronic data bases (Embase, MEDLINE, and Web of Science) were searched from inception to 2019 for randomized controlled trials (RCTs) and non-RCTs addressing the efficacy of zinc supplementation compared with a control nutrition invention on PI outcomes. The primary study outcome was the healing rate of PIs during treatment; the secondary outcomes were the improvement of PI area and pressure ulcer scale for healing (PUSH) score. A total of 7 studies were included in this systematic review and meta-analysis. The intervention group significantly had improved healing vs that of the control group (relative risk, 1.44; 95% CI, 1.01-2.06; P = 0.043, I2 = 19.3%). There was no obvious asymmetry in the funnel plot and no strong evidence of publication bias. Sensitivity analysis showed that meta-analysis has good stability. Studies showed a greater mean reduction in PI area. All the studies we included had a significant improvement in the PUSH score of PIs. Our systematic review and meta-analysis from clinical research confirmed that zinc therapy can promote wound healing and suggest that medical staff should consider providing patients with zinc during PI treatment.

14.
Chemosphere ; 252: 126456, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32182508

RESUMO

Submicron sea spray aerosol (SSA) particles play an essential role in atmospheric chemical processes and the Earth's radiative balance. In this study, different combinations of NaCl, MgSO4, malonic acid (MA), d-fructose and sodium malonate were used to explore the effect of MA on submicron SSA generation. SSA particles were produced at room temperature by bubble bursting from an adjustable home-built SSA generator with sintered glass filters. We found that MA could promote the generation of SSA particles and make the geometric mean diameter (GMD) to decrease for MA concentrations ranging between 8 and 32 mM and then, to increase for MA concentrations in the range of 64-160 mM. d-fructose could improve the generation of SSA with increasing GMD. Interestingly, sodium malonate could significantly enhance the production of SSA, with the change of morphology. Besides, different parameters including flow rate, underwater depth, pore size and size span of sintered glass filter and salinity of water were tested to obtain the characterization of our self-made adjustable SSA generator. Three modes could be found among different SSA generation methods, and they exhibited an obvious accumulation mode around 100 nm. The SSA generation under different conditions was compared with oceanic measurements from the literature, which showed that the sintered glass filter has advantages in generating submicron SSA from film drops.


Assuntos
Aerossóis/química , Água do Mar/química , Modelos Químicos , Oceanos e Mares , Sódio , Cloreto de Sódio/química , Água
15.
Ther Clin Risk Manag ; 16: 133-140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32110031

RESUMO

Purpose: To examine the safety of lateral decubitus positions for cervical laminoplasty. Patients and Methods: A retrospective comparative study was conducted on the safety between the lateral and prone positions in cervical laminoplasty. After screening, 466 patients who underwent cervical laminoplasty at a single medical center were enrolled and categorized into the lateral (n=229) and prone (n=237) groups. Data on positioning time, surgical time, blood loss, complication rates, and surgical outcomes were collected and compared between the two groups. The patients were further divided into underweight, normal weight, overweight, and obesity subgroups according to their body mass index, and the collected data were compared between the lateral and prone groups. Results: The lateral group had a lower incidence of facial pressure ulcers (2.18%) than the prone group (11.39%). However, positioning time, surgical time, blood loss, and surgical outcomes were not significantly different between the two groups. In the subgroup analysis, no significant difference in positioning time, operative time, and blood loss was observed in the underweight, normal weight, and overweight patients between the two groups, but in the obesity subgroup, the lateral group had a significantly shorter positioning time (15.23±6.44 vs 21.63±9.43 min, P=0.045) and operative time (140.16±40.48 vs 178.62±51.82 min, P=0.037) and lesser blood loss (285.31±171.75 vs 430.46±189.84 mL, P=0.044) than the prone group. Conclusion: The lateral position is as safe as the prone position for cervical laminoplasty, but it has advantages over the prone position for patients with obesity.

16.
Sci Total Environ ; 718: 137322, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32092515

RESUMO

It is essential to fully understand the physicochemical properties and sources of atmospheric chromophores to evaluate their impacts on environmental quality and global climate. Three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy is an important method for directly characterizing the occurrences, origins, and chemical behaviors of atmospheric chromophores. However, there is still a lack of adequate information on the sources and chemical structures of EEM-defined chromophores. This situation limits the extensive application of the EEM method in the study of atmospheric chromophores. Under these adverse conditions, this work uses the analysis of EEM data by the parallel factor (PARAFAC) analysis model and a comprehensive comparison of the types and abundances of different chromophores in different aerosol samples (combustion source samples, secondary organic aerosols, and ambient aerosols) to demonstrate that the EEM method can distinguish among different chromophore types and aerosol sources. Indeed, approximately half of all fluorescent substances can be attributed to specific chemicals and sources. These findings provide an important basis for the study of the sources and chemical processes of atmospheric chromophores by the EEM approach.

17.
BMJ Open ; 10(2): e029949, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32060152

RESUMO

OBJECTIVES: To investigate the risk factors associated with early-onset peritonitis (EOP) and their influence on patients' technique survival and mortality. STUDY DESIGN: Retrospective, cohort study. SETTING: Three peritoneal dialysis (PD) units in Shanghai. PARTICIPANTS: PD patients from 1 June 2006 to 1 May 2018 were recruited and followed up until 31 December 2018. According to time-to-first episode of peritonitis, patients were divided into non-peritonitis (n=144), EOP (≤6 months, n=74) and late-onset peritonitis (LOP) (>6 months, n=139). PRIMARY AND SECONDARY OUTCOME MEASURES: EOP was defined as the first episode of peritonitis occurring within 6 months after the initiation of PD. The outcomes were all-cause mortality and technique failure. RESULTS: Of the 357 patients, 74 (20.7%) patients developed their first episode of peritonitis within the first 6 months. Compared with the LOP group, the EOP group had older ages, more female patients, higher Charlson Comorbidity Index (CCI) score, lower serum albumin levels and renal function at the time of initiation of PD, and higher diabetes mellitus and peritonitis rates (p<0.05). Staphylococcus was the most common Gram-positive organism in both EOP and LOP groups. The multivariate logistic regression analysis showed that factors associated with EOP included a higher CCI score (OR 1.285, p=0.011), lower serum albumin level (OR 0.924, p=0.016) and lower Kt/V (OR 0.600, p=0.018) at start of PD. In the Cox proportional-hazards model, EOP was more likely a predictor of technique failure (HR 1.801, p=0.051). There was no difference between EOP and LOP for all-cause mortality. CONCLUSION: A higher CCI score and lower serum albumin level and Kt/V at PD initiation were significantly associated with EOP. EOP also predicted a high peritonitis rate and poor clinical outcome.

18.
Nat Commun ; 11(1): 654, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005831

RESUMO

The taccalonolide microtubule stabilizers covalently bind ß-tubulin and overcome clinically relevant taxane resistance mechanisms. Evaluations of the target specificity and detailed drug-target interactions of taccalonolides, however, have been limited in part by their irreversible target engagement. In this study, we report the synthesis of fluorogenic taccalonolide probes that maintain the native biological properties of the potent taccalonolide, AJ. These carefully optimized, cell-permeable probes outperform commercial taxane-based probes and enable direct visualization of taccalonolides in both live and fixed cells with dramatic microtubule colocalization. The specificity of taccalonolide binding to ß-tubulin is demonstrated by immunoblotting, which allows for determination of the relative contribution of key tubulin residues and taccalonolide moieties for drug-target interactions by activity-based protein profiling utilizing site-directed mutagenesis and computational modeling. This combinatorial approach provides a generally applicable strategy for investigating the binding specificity and molecular interactions of covalent binding drugs in a cellular environment.


Assuntos
Microtúbulos/química , Esteroides/química , Linhagem Celular Tumoral , Humanos , Cinética , Microtúbulos/metabolismo , Modelos Moleculares , Esteroides/metabolismo , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo
19.
Molecules ; 25(3)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979336

RESUMO

This study selected three representative protein-rich biomass-brewer's spent grain (BSG), pasture grass (PG), and cyanobacteria (Arthrospira platensis; AP) for protein extraction with different extraction methods (alkaline treatment, aqueous extraction, and subcritical water extraction). The yield, purity, molecular weight, oil-water interfacial tension, and thermal stability of the obtained proteins derived from different biomass and extraction methods were comprehensively characterized and compared. In the view of protein yield and purity, alkaline treatment was found optimal for BSG (21.4 and 60.2 wt.%, respectively) and AP (55.5 and 68.8 wt.%, respectively). With the decreased oil-water interfacial tension, the proteins from all biomass showed the potential to be emulsifier. BSG and AP protein obtained with chemical treatment presented excellent thermal stability. As a novel method, subcritical water extraction is promising in recovering protein from all three biomass with the comparable yield and purity as alkaline treatment. Furthermore, the hydrolyzed protein with lower molecular weight by subcritical water could promote its functions of foaming and emulsifying.

20.
Environ Sci Process Impacts ; 22(2): 408-417, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31994557

RESUMO

The effects of NO2 and SO2 on the atmospheric heterogeneous reaction of acetic acid on α-Al2O3 in the presence and absence of simulated irradiation were investigated at ambient conditions by using the diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) technique. The experiment was divided into two parts: the heterogeneous reaction experiment and the pre-adsorption reaction experiment under light and dark conditions. In the heterogeneous reaction experiment, solar radiation stimulates the formation of more acetate and nitrate. At the same time, it can promote the partial conversion of sulfites to sulfates in the heterogeneous reaction of SO2 on α-Al2O3 particles. It can be seen that solar radiation plays a significant role in the heterogeneous reactions of inorganic and organic gases on mineral particles. In the pre-adsorption reaction experiment, the pre-adsorbed nitrate, sulfite or sulfate have conspicuous inhibition influence on the formation of acetate in the presence and absence of simulated irradiation. This indicates that the role of pre-adsorbed species should be given more attention for the heterogeneous reaction of acetic acid on the surface of α-Al2O3 particles. When α-Al2O3 particles were pre-adsorbed by different species, simulated irradiation could facilitate the growth of different amounts of acetate. It was found that the extent to which solar radiation contributes to heterogeneous reactions of different kinds of gases on different mineral particles is different. This further emphasizes the complexities of the heterogeneous conversion processes of atmospheric trace gases on the surface of mineral aerosols, promoting a better understanding of the effects of solar radiation and pre-adsorption on the heterogeneous reaction in the atmosphere.


Assuntos
Ácido Acético , Atmosfera , Adsorção , Aerossóis , Sulfatos
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