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1.
Appl Opt ; 60(10): 2861-2869, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33798165

RESUMO

For passive support of large aperture telescopes, geometric layout optimization of the support structure is one of the most critical tasks because it determines the deformation of the mirror under gravity, which affects the wavefront aberration and image quality of the system. Due to a lack of symmetry, the optimization of an elliptical mirror support can be much more complex compared with circular mirrors. We optimize the geometric layout of axial and lateral support for the tertiary mirror of the Thirty Meter Telescope (TMT). Based on a theoretical analysis of the whiffletree principle, a parametric model of axial support is established based on the multi-point constraint equation. The mirror deformation SlopeRMS of the tertiary mirror under vertical gravity is used as the optimization target of the support points. The axial support point position is optimized by means of a simulated annealing algorithm and a mirror-deformed post-processing script written in Python. The TMT tertiary mirror lateral support also uses the whiffletree structure, and its in-plane layout affects the system's resonant modal frequency and the maximum load at each point. According to the dynamic equation and the static principle, the lateral support optimization model is established. The first-order resonant frequency and maximum load of the support point are the objective function. Through optimization of the axial and lateral support, the overall mirror distortion of the system is improved.

2.
J Magn Reson Imaging ; 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33819364

RESUMO

BACKGROUND: Early detection and grading of pancreatic fibrosis (PF) are important and challenging clinical goals. PURPOSE: To determine main pancreatic duct (MPD) diameter, pancreatic thickness, and grades of PF via magnetic resonance elastography (MRE), T1 mapping, and intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI), assessing respective diagnostic performances. STUDY TYPE: Prospective. SUBJECTS: Histopathologic and imaging records (MRE, T1 mapping, and IVIM-DWI) generated by 144 patients between December 2018 and May 2020 were collected for analysis. Grades of PF were distributed as follows: F0, 82; F1, 22; F2, 22; and F3, 18. FIELD STRENGTH/SEQUENCE: 3 T pancreatic MRI, encompassing MRE, T1 mapping, and IVIM-DWI. ASSESSMENT: In all patients, T1 relaxation times, pancreatic stiffness values, IVIM-DWI parameters, MPD diameter, and pancreatic thickness were measured. STATISTICAL TESTS: Receiver operating characteristic (ROC) analysis served to assess imaging parameters useful in diagnosing PF. To identify relations between specific parameters and grades of PF, logistic regression analysis was invoked. RESULTS: Both pancreatic stiffness (r = 0.754; P < 0.001) and T1 relaxation time (r = 0.433; P < 0.001) correlated significantly with PF (%). To determine PF grades ≥F1, a combined model (area under the curve [AUC] = 0.906) performed significantly better than pancreatic stiffness (AUC = 0.855; P < 0.001) or T1 relaxation time (AUC = 0.754; P < 0.001) alone. For PF grades ≥F2 or grade F3, both the combined model (≥F2: AUC = 0.910; F3: AUC = 0.939) and pancreatic stiffness (≥F2: AUC = 0.906; F3: AUC = 0.929) outperformed T1 relaxation time (≥F2: AUC = 0.768 [P = 0.005 and P = 0.004, respectively]; F3: AUC = 0.816 [both P < 0.005]). All IVIM-DWI parameters generated AUC values <0.700. DATA CONCLUSION: A combination of MRE and T1 mapping seems promising in diagnosing various grades of PF, particularly at an early stage. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.

3.
Br J Cancer ; 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795809

RESUMO

BACKGROUND: The mechanism by which immune cells regulate metastasis is unclear. Understanding the role of immune cells in metastasis will guide the development of treatments improving patient survival. METHODS: We used syngeneic orthotopic mouse tumour models (wild-type, NOD/scid and Nude), employed knockout (CD8 and CD4) models and administered CXCL4. Tumours and lungs were analysed for cancer cells by bioluminescence, and circulating tumour cells were isolated from blood. Immunohistochemistry on the mouse tumours was performed to confirm cell type, and on a tissue microarray with 180 TNBCs for human relevance. TCGA data from over 10,000 patients were analysed as well. RESULTS: We reveal that intratumoral immune infiltration differs between metastatic and non-metastatic tumours. The non-metastatic tumours harbour high levels of CD8+ T cells and low levels of platelets, which is reverse in metastatic tumours. During tumour progression, platelets and CXCL4 induce differentiation of monocytes into myeloid-derived suppressor cells (MDSCs), which inhibit CD8+ T-cell function. TCGA pan-cancer data confirmed that CD8lowPlatelethigh patients have a significantly lower survival probability compared to CD8highPlateletlow. CONCLUSIONS: CD8+ T cells inhibit metastasis. When the balance between CD8+ T cells and platelets is disrupted, platelets produce CXCL4, which induces MDSCs thereby inhibiting the CD8+ T-cell function.

4.
Environ Technol ; : 1-21, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33797337

RESUMO

An ultrafiltration membrane developed by our research group was applied to treat simulated emulsified oil wastewater. ATR-FTIR, SEM, TEM, and Zeta potential analyses demonstrated that the modified ultrafiltration membrane (MM) has excellent stability and antifouling capacity than origin membrane (OM), which possesses a pure water flux of 260 L·m-2·h-1 and oil/water (o/w) rejection of 98.5 ± 0.33%. Inorganic salt CaCl2 has more considerable influence than MgSO4 and NaCl under the same mass concentration in the two membranes UF process. Along with concentration increasing, flux sharply reduces; meanwhile, the rejection has an opposite trend. Moreover, permeation flux has a maximum value, and the rejection also gets its optimal state under neutral conditions during the pH value of 2∼12. The membrane also exhibits excellent antifouling performance and anti- o/w adsorption properties with adsorption rate below 0.8% compared with OM, which has an adsorption rate of nearly 2.1%, respectively.A kind of new UF membrane developed by our research group was applied to treat simulated o/w. ATR-FTIR, SEM, TEM, and Zeta potential analyses demonstrated that PVDF-Al2O3/TiO2 material has excellent stability and antifouling capacity. CaCl2 has the greatest influence than MgSO4 and NaCl under the same mass concentration. Moreover, permeation flux has maximum value and the rejection also gets its optimal state under neutral conditions during pH 2∼12. The membrane also exhibits excellent antifouling performance and anti-O/W adsorption properties with with adsorption rate below 0.8% compared with OM which has an adsorption rate nearly 2.1%, respectively.

5.
Breast Cancer Res ; 23(1): 29, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33663585

RESUMO

BACKGROUND: MDM2/MDMX proteins are frequently elevated in hormone receptor-positive (ER+) breast cancer. We sought to determine the antitumor efficacy of the combination of ALRN-6924, a dual inhibitor of MDM2/MDMX, with chemotherapy in ER+ breast cancer models. METHODS: Three hundred two cell lines representing multiple tumor types were screened to confirm the role of TP53 status in ALRN-6924 efficacy. ER+ breast cancer cell lines (MCF-7 and ZR-75-1) were used to investigate the antitumor efficacy of ALRN-6924 combination. In vitro cell proliferation, cell cycle, and apoptosis assays were performed. Xenograft tumor volumes were measured, and reverse-phase protein array (RPPA), immunohistochemistry (IHC), and TUNEL assay of tumor tissues were performed to evaluate the in vivo pharmacodynamic effects of ALRN-6924 with paclitaxel. RESULTS: ALRN-6924 was active in wild-type TP53 (WT-TP53) cancer cell lines, but not mutant TP53. On ER+ breast cancer cell lines, it was synergistic in vitro and had enhanced in vivo antitumor activity with both paclitaxel and eribulin. Flow cytometry revealed signs of mitotic crisis in all treatment groups; however, S phase was only decreased in MCF-7 single agent and combinatorial ALRN-6924 arms. RPPA and IHC demonstrated an increase in p21 expression in both combinatorial and single agent ALRN-6924 in vivo treatment groups. Apoptotic assays revealed a significantly enhanced in vivo apoptotic rate in ALRN-6924 combined with paclitaxel treatment arm compared to either single agent. CONCLUSION: The significant synergy observed with ALRN-6924 in combination with chemotherapeutic agents supports further evaluation in patients with hormone receptor-positive breast cancer.

6.
Braz J Med Biol Res ; 54(5): e10185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729389

RESUMO

Lumbar disc herniation is a common disease characterized by the degeneration of intervertebral discs (IVDs), accompanied by imbalance of metabolic and inflammatory homeostasis. Current studies establish that IVD degeneration is induced by increased apoptosis of nucleus pulposus (NP) cells. However, the underlying mechanisms of NP cell survival/apoptosis are not well elucidated. Here, we reveal a novel mechanism by which mTORC1 signaling controls NP cell survival through regulating metabolic homeostasis. We demonstrated that hyperactivated mTORC1 activity induced by inflammatory cytokines engenders the apoptosis of NP cells, whereas pharmacological inhibition of mTORC1 activity promotes NP cell survival. Using an integrative approach spanning metabolomics and biochemical approaches, we showed that mTORC1 activation enhanced glucose metabolism and lactic acid production, and therefore caused NP cell apoptosis. Our study identified mTORC1 in NP cells as a novel target for IVD degeneration, and provided potential strategies for clinical intervention of lumbar disc herniation.


Assuntos
Degeneração do Disco Intervertebral , Núcleo Pulposo , Apoptose , Humanos , Inflamação/tratamento farmacológico , Degeneração do Disco Intervertebral/tratamento farmacológico , Alvo Mecanístico do Complexo 1 de Rapamicina
7.
Food Chem Toxicol ; 151: 112151, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33774095

RESUMO

This study was to analyze the pyrrolizidine alkaloids (PAs) in Eupatorium fortunei herbs and its derived finished products with a view to evaluating their effects on the proliferation and oligodendrogenesis of neural progenitor cells (NPCs). Using a LC-MS/MS method with 32 PAs reference standards, 8 PAs including intermedine, intermedine N-oxide, lycopsamine, lycopsamine N-oxide, retronecine, seneciphylline and senkirkine and 7-acetylintermedine N-oxide were identified with intermedine N-oxide and lycopsamine N-oxide being most abundant. The total PA amounts were found to vary from 0.18 to 61.81 µg/g in 30 batches of herbs and from 0.86 to 36.96 µg/g in 4 commercial finished products, respectively. Risk assessments indicated that the short-term intake seemed unlikely lead to acute toxic effects but the chronic use warranted cautions. Using NPCs derived from mouse induced pluripotent stem cells as an in vitro testing model, intermedine, intermedine N-oxide and lycopsamine N-oxide appeared to decrease cell viability at 30 µM whereas intermedine N-oxide inhibited oligodendrogenesis of NPCs at 10 µM. The present results suggested that the PAs in the majority of E. fortunei herbs and the derived products not only resulted in their exposure far exceeding the acceptable intake limit (i. e. 1.0 µg PA per day for adults) in herbal medicinal products recommended by the European Medicines Agency but also induced neurotoxicity to NPCs in vitro.

8.
Inorg Chem ; 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33711236

RESUMO

Luminescent copper(I) halide complexes with bi- and tridentate rigid ligands have gained wide research interests. In this paper, six tetracoordinate dinuclear copper(I) halide complexes, Cu2X2(ppda)2 [ppda = 2-[2-(dimethylamino)phenyl(phenyl)phosphino]-N,N-dimethylaniline, X = I (1), Br (2), Cl (3)] and Cu2X2(pfda)2 [pfda = 2-[2-(dimethylamino)-4-(trifluoromethyl)phenyl(phenyl)phosphino]-N,N-dimethyl-5-trifluoromethylaniline, X = I (4), Br (5), Cl (6)], were successfully prepared and systematically characterized on their structures and photophysical properties. Complexes 1-5 have a centrosymmetric form with a planar Cu2X2 unit, and complex 6 has a mirror symmetry form with a butterfly-shaped Cu2X2. Solid complexes 1, 4, and 5 emit delayed fluorescence at room temperature, intense blue to greenish yellow (λmax = 443-570 nm) light, and their peak wavelengths are located at 443-570 nm with microsecond lifetimes (τ = 0.4-19.2 µs, ΦPL = 0.05-0.48). Complexes 2, 3, and 6 show prompt fluorescence, very weak yellowish green to yellow (λmax = 534-595 nm) emission with peak wavelengths at 534-595 nm, and lifetimes in nanoseconds (τ = 4.4-9.3 ns, ΦPL < 0.0001). (Metal + halide) to ligand and intraligand charge transitions are the main origin of the emission of the complexes. Solution-processed, complex-4-based nondoped and doped devices emit yellow green light with CIE coordinated at (0.41, 0.51), a maximum EQE up to 0.17%, and luminance reaching 75.52 cd/m2.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33713950

RESUMO

Lipase inhibitors are an attractive class of hypolipidemic compounds, which inhibit the activity of human pancreatic lipase, thereby preventing the absorption of triglycerides in vivo. As a library of promising lead compounds for drug development, traditional Chinese medicine (TCM) has gained growing attention in quick discovery and identification of enzyme inhibitors of natural-origin. The purpose of this work was to discover unknown lipase inhibitors from Alisma orientale by the activity oriented analysis method thin-layer chromatography-bioautography, then use electrospray ionization mass spectrometry technology via the elution based TLC-MS interface to identify their structures. As a result, eleven natural lipase inhibitors from Alisma orientale extracts were identified based on molecular mass and fragment ions obtained by HPTLC-MS, and further confirmed by a series of complementary means including UV spectra, 1H NMR characteristic proton signals and polarity of compounds, eleven lipase inhibitors were tentatively assigned as triterpenoids: alisol B (m/z 495.50 [M + Na]+), alisol B 23-acetate (m/z 537.58 [M + Na]+), 11-deoxy-alisol B (m/z 479.50 [M + Na]+), 11-deoxy-alisol B 23-acetate (m/z 521.50 [M + Na]+), alisol A/epialisol A (m/z 513.50 [M + Na]+), 16-oxo-11-deoxy-alisol A (m/z 511.50 [M + Na]+), 16-oxo-alisol A (527.50 [M + Na] +), alisol C (m/z 509.58 [M + Na]+), alisol C 23-acetate (m/z 551.50 [M + Na]+), alisol M 23-acetate (m/z 567.50 [M + Na]+), and alismanol Q/neoalisol (m/z 493.42 [M + Na]+). The integrated approach is an efficient method for rapid screening lipase inhibitors from complex plant extracts and provides a reasonable and favorable basis for the identification and separation of other enzymatic system and other important compounds with therapeutic values.

10.
J AOAC Int ; 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33774674

RESUMO

BACKGROUND: Sample preparation is the most crucial step in the whole analytical schemes. Micro matrix solid-phase dispersion, as a method for microextraction of analytes, has prevailed recently for its low sample and extraction solvent consumption. However, small amount of adsorbent, sample or short extraction time always brings uncertainty on the result when using this method. OBJECTIVE: To develop a simple and reliable method by deep eutectic solvents assisted ultrasonic-synchronized matrix solid-phase dispersion microextraction for the analysis of four flavonoids in Scutellariae Radix based on the concept of quality by design. METHODS: Molecular sieve ZSM-5 was used as new adsorbent in MSPD process. Single factor and Box-Behnken design were used to construct the design space. RESULTS: Verification of experiment demonstrated that the design space is robust. Under the optimal conditions, all analytes showed good linearity (R2 > 0.999), high reproducibility (RSD < 2.24%) and stability (RSD < 2.87%), satisfactory recoveries (95.90∼102.31%), which indicated that the established method is reliable and reproducible. Moreover, it has been successfully applied to determine the flavonoids in nine batches of Scutellariae Radix. CONCLUSION: The result indicated a great potential on analyzing precious complicated samples and helps to promote the quality control of the sample preparation process of traditional Chinese medicines. HIGHLIGHTS: A systematic approach by using a facile DES assisted ultrasonic-synchronized matrix solid-phase dispersion extraction coupled with HPLC for the analysis of flavonoids in Scutellariae Radix has been developed based on the concept of quality by design.

11.
Cancer Cell ; 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33740421

RESUMO

Many cancers, including pancreatic ductal adenocarcinoma (PDAC), depend on autophagy-mediated scavenging and recycling of intracellular macromolecules, suggesting that autophagy blockade should cause tumor starvation and regression. However, until now autophagy-inhibiting monotherapies have not demonstrated potent anti-cancer activity. We now show that autophagy blockade prompts established PDAC to upregulate and utilize an alternative nutrient procurement pathway: macropinocytosis (MP) that allows tumor cells to extract nutrients from extracellular sources and use them for energy generation. The autophagy to MP switch, which may be evolutionarily conserved and not cancer cell restricted, depends on activation of transcription factor NRF2 by the autophagy adaptor p62/SQSTM1. NRF2 activation by oncogenic mutations, hypoxia, and oxidative stress also results in MP upregulation. Inhibition of MP in autophagy-compromised PDAC elicits dramatic metabolic decline and regression of transplanted and autochthonous tumors, suggesting the therapeutic promise of combining autophagy and MP inhibitors in the clinic.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33738769

RESUMO

To investigate the characteristics of pulmonary artery distensibility (PAD) in patients with acute pulmonary embolism (APE) and to assess whether a relationship exists between PAD and the disease severity. Clinical and radiological data of 30 APE patients who underwent retrospective electrocardiogram (ECG)-gated computed tomography pulmonary angiography (CTPA) with a definite diagnosis of APE were retrospectively reviewed in the present study, including 15 subjects in severe (SPE) group and 15 subjects in non-severe (NSPE) group. PAD and cardiac function parameters were compared between the two groups, their relationships were investigated, and receiver operating characteristic (ROC) curves were used to determine the sensitivity and specificity of the above parameters for the diagnosis of APE severity. The PAD decreased in the following order: NSPE group (6.065 ± 2.114) × 10-3 (%/mmHg), and SPE group (4.334 ± 1.777) × 10-3 (%/mmHg) (P < 0.05). All the cardiac function parameters except RA/LAdiameter showed statistically significant different values between the two groups (P < 0.05). As APE severity increased, the cardiac morphological measurements of RV/LVdiameter, RV/LVarea, RVEDV/LVEDV and RVESV/LVESV increased. There was a weak to moderate negative correlation between PAD and PAmax, PAmin, PA/AAmin, PA/AAmax, RV/LVdiameter, RV/LVarea (r = -0.393 to -0.625), that is, PAD was inversely correlated with cardiac function parameters. There was a moderate negative correlation between PAD and hemoptysis(r = -0.672). The area under the ROC curve (AUC) of PAD was 0.724, the critical value was 4.137 × 10-3  mm/Hg, and the sensitivity and specificity were 60.0% and 93.3%, respectively. PAmin showed the strongest discriminatory power to identify high-risk patients (AUC = 0.827), with the highest sensitivity of 100%, which was also achieved by RA/LAarea. The PAD obtained by retrospective ECG-gated CTPA could be an indicator to be used in the evaluation of the presence and severity of APE.

13.
Clin Exp Rheumatol ; 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33769269

RESUMO

OBJECTIVES: To explore the clinical characteristics, diagnosis and the therapeutic effect of Kimura's disease (KD). METHODS: Clinical data of 20 patients with pathologically confirmed KD admitted to Peking University People's Hospital from June 2000 to June 2019 were analysed. A total of 20 confirmed KD patients were enrolled in the study, 18 male and 2 female, with age-onset ranging from 2 to 58 years. RESULTS: The masses appear as focal, painless, and immovable with an unclear boundary. The most common predilection is head-neck region (n=15, 75%). 15 patients showed peripheral blood eosinophilia. 14 of 14 patients presented with increased serum IgE level. The prominent pathological characteristic is marked lymphoid hyperplasia accompanied by various degrees of vascular hyperplasia and eosinophil infiltration. Among the 20 patients, 12 experienced recurrence of disease after treatment (surgical resection alone: 9/9; oral corticosteroids combined with immunosuppressants: 1/3; surgical resection followed by oral corticosteroids combined with immunosuppressants: 2/6). CONCLUSIONS: KD should be considered when the patient presents with head-neck swellings and lymphadenopathy, accompanied by an increase of IgE and eosinophil. Compared with surgery alone, combined therapy seems to be a promising treatment option to reduce the recurrence rate.

14.
J Phys Chem Lett ; : 2437-2443, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33661637

RESUMO

CsPbI3 perovskite nanocrystals (NCs) have recently emerged as promising materials for optoelectronic devices because of their superior properties. However, the poor stability of the CsPbI3 NCs induced by easy ligand desorption represents a key issue limiting their practical applications. Herein, we report stable and highly luminescent black-phase CsPbI3 NCs passivated by novel ligands of sodium dodecyl sulfate (SDS). Theoretical calculation results reveal a stronger adsorption energy of SDS molecules at the CsPbI3 surface than that of commonly used oleic acid. As a result, the defect formation caused by the ligand loss during the purification process is greatly suppressed. The optimized SDS-CsPbI3 NCs exhibit significantly reduced surface defects, much enhanced stability, and superior photoluminescence efficiency. The red perovskite light-emitting diodes based on the SDS-CsPbI3 NCs demonstrate an external quantum efficiency of 8.4%, which shows a 4-fold improvement compared to the devices based on the oleic acid-modified CsPbI3 NCs.

15.
J Colloid Interface Sci ; 594: 64-72, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33756369

RESUMO

Surface modification has been considered a simple and effective strategy to enhance the photocatalytic activity of polymeric carbon nitride (CN), but resultant difference of energy band structures between the modified surface layer and the unmodified inside in the sample has always been neglected. Herein, maleoyl-modified CN (MaCN) was simply prepared via a dehydration reaction between CN and maleic acid, and exhibits enhanced charge separation, optical absorption, and thus photocatalytic hydrogen evolution activity, relative to the bulk CN. The surface modification causes variation of the band structure, suggesting the difference of band levels between the surface layer with maleoyl-modification and the inside without any modification in MaCN, and the surface layer and the inside with matched band levels form type-II core-shell homojunction to enhance the charge separation. This work expounds a conceptual framework of core-shell homojunction in surface-modified CN photocatalysts.

16.
J Chromatogr A ; 1642: 462040, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33721813

RESUMO

This work presents a simple, rapid and green chiral analysis method for five triazole fungicides (penconazole, tebuconazole, triadimefon, myclobutanil, and triadimenol) in tobacco, by which the samples were cleaned up by the novel pass-through solid phase extraction and subsequently the stereoisomers were separated and determined by the supercritical fluid chromatography-tandem mass spectrometry (SFC-MS/MS). Optimized separation of the stereoisomers was achieved on an ACQUITY UPC2 Trefoil AMY 1 column within 6 min. Under fortified concentration levels of 0.1, 0.5 and 2.0 mg/kg, the mean recoveries were 82.8-106.6%, the intra-day relative standard deviations (RSDs) were 1.1-6.6%, and the inter-day RSDs were 2.5-5.6%. The correlation coefficient was greater than 0.9926 for all studied analytes within the range of 10-500 ng/mL. The limits of detection (LODs) for all stereoisomers ranged from 0.26 µg/kg to 3.24 µg/kg. The established method was subsequently successfully applied to analyze authentic samples, confirming that this method is a novel, rapid and environmentally friendly method for the stereoselective separation of triazole fungicides in tobacco.

17.
Adv Mater ; : e2006292, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33749011

RESUMO

The rapid progress of proton exchange membrane fuel cells (PEMFCs) and alkaline exchange membrane fuel cells (AMFCs) has boosted the hydrogen economy concept via diverse energy applications in the past decades. For a holistic understanding of the development status of PEMFCs and AMFCs, recent advancements in electrocatalyst design and catalyst layer optimization, along with cell performance in terms of activity and durability in PEMFCs and AMFCs, are summarized here. The activity, stability, and fuel cell performance of different types of electrocatalysts for both oxygen reduction reaction and hydrogen oxidation reaction are discussed and compared. Research directions on the further development of active, stable, and low-cost electrocatalysts to meet the ultimate commercialization of PEMFCs and AMFCs are also discussed.

18.
Aging (Albany NY) ; 13(4): 5674-5685, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33589574

RESUMO

Tumor-associated macrophages (TAMs) are important components of the tumor microenvironment, which are characterized by pro-tumor M2 phenotype and correlate with poor survival of nasopharyngeal carcinoma (NPC). Heme oxygenase-1 (HO-1) plays a crucial role in macrophage polarization toward M2 phenotype, but its prognosis significance in NPC has been rarely determined. To gain insights into the HO-1 expression profile and to determine the clinical significance of HO-1 in NPC, we performed immunohistochemistry analyses in 126 NPC specimens. CD163, a highly specific marker of M2 macrophages, was used as a surrogate for the polarization state of TAMs. Our results showed that high expression of HO-1 and CD163 were detected in TAMs for 57.9% (73/126) and 61.9% (78/126) of the studied patients, and both of them were significantly associated with worse survival. Additionally, a significant correlation between the intensities of HO-1 and CD163 was identified, and HO-1 exhibited a superior ability in predicting survival compared with CD163. Our study revealed for the first time that overexpression of HO-1 characterized a poor-prognosis subtype in NPC. Individualized therapy targeting HO-1 might serve as a promising treatment modality for NPC.

19.
Medicine (Baltimore) ; 100(3): e24356, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33546070

RESUMO

ABSTRACT: To investigate the characteristics of pulmonary artery distensibility (PAD) in patients with acute pulmonary embolism (APE) and to assess the correlation of PAD with APE severity and right ventricular function. A total of 33 patients who underwent retrospective electrocardiogram (ECG)-gated computed tomography pulmonary angiography (CTPA) with a definite diagnosis of APE were included in the study. According to APE severity, the patients were divided into severe (SPE) and non-severe (NSPE) groups. Data from a control group without APE matching the basic demographics of the APE patients were collected. Pulmonary artery distensibility (PAD) and right ventricular function parameters were compared among the 3 groups, their relationships were investigated, and receiver operating characteristic (ROC) curves were used to determine the sensitivity and specificity of the above parameters for the diagnosis of APE severity. The PAD values of the control, NSPE, and SPE groups were (7.877 ±â€Š2.637) × 10-3 mm/Hg, (6.050 ±â€Š2.011) × 10-3 mm/Hg, (4.321 ±â€Š1.717) × 10-3 mm/Hg, respectively (P < .01). There were statistically significant differences in right ventricular function parameters among the 3 groups (P < .05). The correlation analysis between PAD and right ventricular function parameters showed a weak negative correlation (r = -0.281--0.392). The area under the ROC curve of PAD was 0.743, the critical value was 4.200, and the sensitivity and specificity were 62.5% and 94.1%, respectively. The PAD obtained by retrospective ECG-gated CTPA could accurately evaluate APE severity and right ventricular function. As the severity of APE increases, PAD decreases, which is helpful to identify patients at high risk of APE.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Artéria Pulmonar/anormalidades , Embolia Pulmonar/fisiopatologia , Função Ventricular Direita/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/fisiopatologia , Embolia Pulmonar/patologia , Curva ROC , Estudos Retrospectivos
20.
BMJ Open ; 11(2): e039653, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33550227

RESUMO

OBJECTIVES: This study aims to assess the cost-effectiveness of three renal replacement therapy (RRT) modalities as well as proposed changes of scheduled policies in RRT composition in Guangzhou city. METHODS: From a payer perspective, we designed Markov model-based cost-effectiveness analyses to compare the cost-effectiveness of three RRT modalities and four different scheduled policies to RRT modalities in Guangzhou over three time horizons (5, 10 and 15 years). The current situation (scenario 1: haemodialysis (HD), 73%; peritoneal dialysis (PD), 14%; kidney transplantation (TX), 13%) was compared with three different scenarios: an increased proportion of incident RRT patients on PD (scenario 2: HD, 47%; PD, 40%; TX, 13%); on TX (scenario 3: HD, 52%; PD, 14%; TX, 34%); on both PD and TX (Scenario 4: HD, 26%; PD, 40%; TX, 34%). RESULTS: Over 5-year time horizon, HD was dominated by PD. At a willingness-to-pay (WTP) threshold of US$44 300, TX was cost-effective compared with PD with an incremental cost-effectiveness ratio of US$35 518 per quality-adjusted life year (QALY) gained. The scenario 2 held a dominant position over the scenario 1, with a net saving of US$ 5.92 million and an additional gain of 6.24 QALYs. The scenarios 3 and 4 were cost-effective compared with scenario 1 at a WTP threshold of US$44 300. The above results were consistent across the three time horizons. CONCLUSIONS: TX is the most cost-effective RRT modality, followed in order by PD and HD. The strategy with an increased proportion of incident patients on PD and TX is cost-effective compared with the current practice pattern at the given WTP threshold. The planning for RRT service delivery should incorporate efforts to increase the utilisation of PD and TX in China.

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