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1.
Nature ; 611(7935): 284-288, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36289341

RESUMO

Single-atom catalysts1 make exceptionally efficient use of expensive noble metals and can bring out unique properties1-3. However, applications are usually compromised by limited catalyst stability, which is due to sintering3,4. Although sintering can be suppressed by anchoring the metal atoms to oxide supports1,5,6, strong metal-oxygen interactions often leave too few metal sites available for reactant binding and catalysis6,7, and when exposed to reducing conditions at sufficiently high temperatures, even oxide-anchored single-atom catalysts eventually sinter4,8,9. Here we show that the beneficial effects of anchoring can be enhanced by confining the atomically dispersed metal atoms on oxide nanoclusters or 'nanoglues', which themselves are dispersed and immobilized on a robust, high-surface-area support. We demonstrate the strategy by grafting isolated and defective CeOx nanoglue islands onto high-surface-area SiO2; the nanoglue islands then each host on average one Pt atom. We find that the Pt atoms remain dispersed under both oxidizing and reducing environments at high temperatures, and that the activated catalyst exhibits markedly increased activity for CO oxidation. We attribute the improved stability under reducing conditions to the support structure and the much stronger affinity of Pt atoms for CeOx than for SiO2, which ensures the Pt atoms can move but remain confined to their respective nanoglue islands. The strategy of using functional nanoglues to confine atomically dispersed metals and simultaneously enhance their reactivity is general, and we anticipate that it will take single-atom catalysts a step closer to practical applications.

2.
J Opt Soc Am A Opt Image Sci Vis ; 41(4): 664-673, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568666

RESUMO

This study proposes two types of composite structures based on gold nano circular and nano square rings on a gold thin film for plasmonic refractive index sensing. The finite-difference time-domain method was used for simulation and analysis. The nano square ring composite structure showed superior performance, with five surface plasmon resonance modes, and a peak sensitivity and figure of merit in a liquid environment of 1600 nm/RIU and 86R I U -1, respectively. The sensing performances of localized surface plasmon resonance modes of both structures are superior to those of the propagating surface plasmon resonance modes. The proposed composite structures can provide a reference for refractive index sensing and have broad application prospects in bio-chemistry.

3.
Nano Lett ; 23(8): 3326-3333, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37026788

RESUMO

On-chip photonic systems play crucial roles in nanoscience and nanoapplications, but coupling external light to these subwavelength devices is challenging due to a large mode mismatch. Here, we establish a new scheme for realizing highly miniaturized couplers for efficiently exciting on-chip photonic devices in a controllable way. Relying on both resonant and Pancharatnam-Berry mechanisms, our meta-device can couple circularly polarized light to a surface plasmon, which is then focused into a spot placed with a target on-chip device. We experimentally demonstrate two meta-couplers. The first can excite an on-chip waveguide (with a 0.1λ × 0.2λ cross section) with an absolute efficiency of 51%, while the second can achieve incident spin-selective excitation of a dual-waveguide system. Background-free excitation of a gap-plasmon nanocavity with the local field enhanced by >1000 times is numerically demonstrated. Such a scheme connects efficiently propagating light in free space and localized fields in on-chip devices, being highly favored in many integration-optics applications.

4.
Angew Chem Int Ed Engl ; 63(20): e202402093, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38438306

RESUMO

Lead-based radicals in the oxidation state of +1 are elusive species and are highly challenging to isolate in the condensed phase. In this study, we present the synthesis and characterization of the first isolable free plumbylyne radical 2 bearing a one-coordinate Pb(I) atom. It reacts with an N-heterocyclic carbene (NHC) to afford a two-coordinate NHC-ligated Pb(I) radical 3. 2 and 3 represent the first isolable Pb(I)-based radicals. Theoretical calculations and electron paramagnetic resonance analysis revealed that the unpaired electron mainly resides at the Pb 6p orbital in both radicals. Owing to the unique one-coordinate nature of the Pb atom in 2, it possesses two-fold orbital pseudo-degeneracy and substantial unquenched orbital angular momentum, and exhibits hitherto strongest g-factor anisotropy (gx,y,z=1.496, 1.166, 0.683) amongst main group radicals. Preliminary investigations into the reactivity of 2 unveiled its Pb-centered radical nature, and plumbylenes were isolated as products.

5.
Opt Express ; 31(21): 34112-34122, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37859175

RESUMO

Plasmonic vortices have shown a wide range of applications in on-chip photonics due to their fascinating properties of the orbital angular momenta (OAM) and phase singularity. However, conventional devices to generate them suffer from issues of low efficiencies and limited functionalities. Here, we establish a systematic scheme to construct high-efficiency bifunctional metasurfaces that can generate two plasmonic vortices exhibiting distinct topological charges, based on a series of reflective meta-atoms exhibiting tailored reflection-phases dictated by both resonant and geometric origins. As a benchmark test, we first construct a meta-coupler with meta-atoms exhibiting geometric phases only, and experimentally demonstrate that it can generate a pre-designed plasmonic vortex at the wavelength of 1064 nm with an efficiency of 27% (56% in simulation). Next, we design/fabricate two bifunctional metasurfaces with meta-atoms integrated with both resonant and geometric phases, and experimentally demonstrate that they can generate divergent (or focused) or convergent (or defocused) plasmonic vortices with district OAM as shined by circularly polarized light with opposite helicity at 1064 nm wavelength. Our work provides an efficient platform to generate plasmonic vortices as desired, which can find many applications in on-chip photonics.

6.
Inorg Chem ; 62(51): 20906-20912, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38095884

RESUMO

Treatment of N-heterocyclic carbene (NHC) ligated germylidenylphosphinidene MsFluidtBu-GeP(NHCiPr) (where MsFluidtBu is a bulky hydrindacene substituent, and NHCiPr is 1,3-diisopropyl-4,5-dimethyl-imidazolin-2-ylidene) with mesityl azide and 4-tertbutylphenyl azide afforded NHC coordinated formal germanimidoyl-phosphinidenes, which represent the first compounds bearing both Ge═N double bond and phosphinidene functionalities. Studies of the chemical properties revealed that the reactions preferred to occur at the Ge═N double bond, which underwent [2 + 2] cycloadditions with CO2 and ethyl isocyanate, and coordinated with coinage metals through the nitrogen atom.

7.
Exp Cell Res ; 411(2): 113001, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973945

RESUMO

Autophagy is involved in the activation of hepatic stellate cells (HSCs) and liver fibrosis. Previous studies have shown that interleukin 10 (IL-10) has a marked therapeutic effect against liver fibrosis. However, few studies have evaluated the effect of IL-10 on autophagy in HSCs and fibrotic livers. The aim of this study was to assess the effect of IL-10 on the autophagy of HSCs in vitro and in vivo and then to explore the underlying pathway. In vitro, The results revealed that IL-10 had inhibitory effects on hydrogen peroxide (H2O2)-induced autophagy, as evidenced by the decreased LC3II/I ratio and Beclin1 expression, increased p62 expression, reduced numbers of autophagosomes, and blocked autophagy initiation in HSCs. Mechanistically, IL-10 significantly promoted the phosphorylation of the signal transducer and activator of transcription 3(STAT3) and mammalian target of rapamycin (mTOR), leading to the activation of STAT3 and mTOR, which in turn inhibited autophagy. In vivo, the increased expression of IL-10 in fibrotic livers inhibited significantly liver fibrosis and decreased the autophagic activity in fibrotic livers and HSCs. Overall, our results indicate that IL-10 suppressed H2O2-induced autophagy in HSCs by activating the STAT3-mTOR signaling pathway. Present study provides a new theoretical basis for the anti-fibrotic effects of IL-10.


Assuntos
Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Interleucina-10/metabolismo , Interleucina-10/farmacologia , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/patologia , Autofagia/efeitos dos fármacos , Linhagem Celular , Células Estreladas do Fígado/patologia , Humanos , Peróxido de Hidrogênio/farmacologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/prevenção & controle , Modelos Biológicos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
8.
World J Surg Oncol ; 21(1): 289, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37700312

RESUMO

BACKGROUND: Uncut Roux-en-Y (URY) effectively alleviates the prevalent complexities connected with RY, such as Roux-en-Y stasis syndrome (RSS). Nevertheless, for gastric cancer (GC) patients, it is still controversial whether URY has an impact on long-term prognosis and whether it has fewer afferent loop recanalization. Therefore, compare whether URY and RY have differences in prognosis and long-term complications of GC patients undergoing totally laparoscopic gastrectomy (TLG). METHODS: We analyzed the data of patients who underwent TLG combined with digestive tract reconstruction from dual-center between 2016 and 2022. Only patients undergoing URY and RY were selected for analysis. Relapse-free survival (RFS) and overall survival (OS) were estimated. Bias between the groups was reduced by propensity score matching (PSM). The Cox proportional hazard regression model was used to further analyze the influence of URY on prognosis. RESULTS: Two hundred forty two GC patients were enrolled. The URY had significantly shorter operation time, liquid food intake time, and in-hospital stays than the RY (P < 0.001). The URY had fewer long-term and short-term postoperative complications than the RY, especially with regard to RSS, reflux esophagitis, and reflux gastritis. The 3-year and 5-year OS of the URY group and the RY group before PSM: 87.5% vs. 65.6% (P < 0.001) and 81.4% vs. 61.7% (P = 0.001). PSM and Cox multivariate analysis confirmed that compared to RY, URY can improve the short-term and long-term prognosis of GC patients. CONCLUSION: TLG combined with URY for GC, especially for advanced, older, and poorly differentiated patients, may promote postoperative recovery and improve long-term prognosis.


Assuntos
Laparoscopia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Estudos Retrospectivos , Anastomose em-Y de Roux , Gastrectomia/efeitos adversos , Laparoscopia/efeitos adversos
9.
Angew Chem Int Ed Engl ; 62(22): e202301507, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37005226

RESUMO

Electrochemical reduction reaction of carbon monoxide (CORR) offers a promising way to manufacture acetic acid directly from gaseous CO and water at mild condition. Herein, we discovered that the graphitic carbon nitride (g-C3 N4 ) supported Cu nanoparticles (Cu-CN) with the appropriate size showed a high acetate faradaic efficiency of 62.8 % with a partial current density of 188 mA cm-2 in CORR. In situ experimental and density functional theory calculation studies revealed that the Cu/C3 N4 interface and metallic Cu surface synergistically promoted CORR into acetic acid. The generation of pivotal intermediate -*CHO is advantage around the Cu/C3 N4 interface and migrated *CHO facilitates acetic acid generation on metallic Cu surface with promoted *CHO coverage. Moreover, continuous production of acetic acid aqueous solution was achieved in a porous solid electrolyte reactor, indicating the great potential of Cu-CN catalyst in the industrial application.

10.
Ren Fail ; 44(1): 1443-1453, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36017686

RESUMO

BACKGROUND: Nephrotic syndrome (NS) and nephrotic-range proteinuria (NRP) are uncommon in IgA nephropathy (IgAN), and their clinicopathology and prognosis have not been discussed. Podocytes may play an important role in both clinical phenotypes. METHODS: We investigated 119 biopsy-proven IgAN patients with proteinuria over 2 g/d. The patients were divided into three groups according to proteinuria level: the overt proteinuria (OP) group, NS group, and NRP group. In addition, according to the severity of foot process effacement (FPE), the patients were divided into three groups: the segmental FPE (SFPE) group, moderate FPE (MFPE) group, and diffuse FPE (DFPE) group. The outcome was survival from a combined event defined by a doubling of the baseline serum creatinine and a 50% reduction in eGFR or ESRD. RESULTS: Compared with the NRP group, patients in the NS group had more severe microscopic hematuria, presented with more severe endocapillary hypercellularity and had a higher percentage of DFPE. The Kaplan-Meier curve showed that MFPE patients had a better outcome in the NRP group <50% of tubular atrophy/interstitial fibrosis. In the multivariate model, the NRP group (HR = 17.098, 95% CI = 3.835-76.224) was associated with an increased risk of the combined event, while MFPE (HR = 0.260, 95% CI = 0.078-0.864; p = 0.028) was associated with a reduced risk of the combined event. After the addition of renin-angiotensin system inhibitors (RASi), the incidence of the combined event in the MFPE group (HR = 0.179, 95% CI = 0.047-0.689; p = 0.012) was further reduced. CONCLUSIONS: NS presented more active lesions and more severe FPE in IgAN. NRP was an independent risk factor for progression to the renal endpoint, while MFPE indicated a better prognosis in NRP without obvious chronic renal lesions, which may benefit from RASi.


Assuntos
Glomerulonefrite por IGA , Síndrome Nefrótica , Podócitos , Glomerulonefrite por IGA/complicações , Glomerulonefrite por IGA/tratamento farmacológico , Glomerulonefrite por IGA/patologia , Humanos , Rim/patologia , Síndrome Nefrótica/complicações , Síndrome Nefrótica/etiologia , Podócitos/patologia , Proteinúria/patologia , Estudos Retrospectivos
11.
J Am Chem Soc ; 143(50): 21364-21378, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34881868

RESUMO

Atomically dispersed noble metal catalysts have drawn wide attention as candidates to replace supported metal clusters and metal nanoparticles. Atomic dispersion can offer unique chemical properties as well as maximum utilization of the expensive metals. Addition of a second metal has been found to help reduce the size of Pt ensembles in bimetallic clusters; however, the stabilization of isolated Pt atoms in small nests of nonprecious metal atoms remains challenging. We now report a novel strategy for the design, synthesis, and characterization of a zeolite-supported propane dehydrogenation catalyst that incorporates predominantly isolated Pt atoms stably bonded within nests of Zn atoms located within the nanoscale pores of dealuminated zeolite Beta. The catalyst is stable in long-term operation and exhibits high activity and high selectivity to propene. Atomic resolution images, bolstered by X-ray absorption spectra, demonstrate predominantly atomic dispersion of the Pt in the nests and, with complementary infrared and nuclear magnetic resonance spectra, determine a structural model of the nested Pt.

12.
J Am Chem Soc ; 143(48): 20144-20156, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34806881

RESUMO

Atomically dispersed supported metal catalysts offer new properties and the benefits of maximized metal accessibility and utilization. The characterization of these materials, however, remains challenging. Using atomically dispersed platinum supported on crystalline MgO (chosen for its well-defined bonding sites) as a prototypical example, we demonstrate how systematic density functional theory calculations for assessing all the potentially stable platinum sites, combined with automated analysis of extended X-ray absorption fine structure (EXAFS) spectra, leads to unbiased identification of isolated, surface-enveloped platinum cations as the catalytic species for CO oxidation. The catalyst has been characterized by atomic-resolution imaging and EXAFS and high-energy resolution fluorescence detection X-ray absorption near edge spectroscopy. The proposed platinum sites are in agreement with experiment. This theory-guided workflow leads to rigorously determined structural models and provides a more detailed picture of the structure of the catalytically active site than what is currently possible with conventional EXAFS analyses. As this approach is efficient and agnostic to the metal, support, and catalytic reaction, we posit that it will be of broad interest to the materials characterization and catalysis communities.

13.
Small ; 17(16): e2004665, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33185034

RESUMO

When metal nanoparticles on supports are made smaller and smaller-to the limit of atomic dispersion-they become cationic and take on new catalytic properties that are only recently being discovered. The synthesis of these materials is reviewed, including their structure characterization-especially by atomic-resolution electron microscopy and X-ray absorption and infrared spectroscopies-and relationships between structure and catalyst performance, for reactions including hydrogenations, oxidations, and the water gas shift. Structure determination is challenging because of the intrinsic nonuniformity of the support surfaces-and therefore the structures on them-but fundamental understanding has advanced rapidly, benefiting from nearly uniform catalysts consisting of metals on well-defined-crystalline-supports and their characterization by spectroscopy and microscopy. Recent advances in atomic-resolution electron microscopy have spurred the field, providing stunning images and deep insights into structure. The iridium catalysts have typically been made from organoiridium precursors, opening the way to understanding and control of the metal-support bonding and ligands on the metal, including catalytic reaction intermediates. Platinum catalysts are usually made with less precision, from salt precursors, but they catalyze a wider array of reactions than the iridium, typically being stable at higher temperatures and seemingly offering rich prospect for discovery of new catalysts.

14.
Hum Mutat ; 41(1): 212-221, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31489982

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common X-linked enzymopathies caused by G6PD gene variant. We aimed to provide the characteristics of G6PD deficiency and G6PD gene variant distribution in a large Chinese newborn screening population. We investigated the prevalence of G6PD in China from 2013 to 2017. Then, we examined G6PD activity and G6PD gene in representative Chinese birth cohort to explore the distribution of G6PD gene variant in 2016. We then performed multicolor melting curve analysis to classify G6PD gene variants in 10,357 neonates with activity-confirmed G6PD deficiency, and DNA Sanger sequencing for G6PD coding exons if hot site variants were not found. The screened population, organizations, and provinces of G6PD deficiency were increased from 2013 to 2017 in China. The top five frequency of G6PD gene variants were c.1376G>T, c.1388G>A, c.95A>G, c.1024C>T, and c.871G>A and varied in different provinces, with regional and ethnic features, and four pathogenic variant sites (c.152C>T, c.290A>T, c.697G>C, and c.1285A>G) were first reported. G6PD deficiency mainly occurs in South China, and the frequency of G6PD gene variant varies in different regions and ethnicities.


Assuntos
Variação Genética , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Deficiência de Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/genética , Triagem Neonatal , Alelos , China/epidemiologia , Mapeamento Cromossômico , Análise Mutacional de DNA/métodos , Feminino , Genes Ligados ao Cromossomo X , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Deficiência de Glucosefosfato Desidrogenase/história , História do Século XXI , Humanos , Incidência , Recém-Nascido , Masculino , Mutação , Triagem Neonatal/métodos , Triagem Neonatal/normas , Vigilância da População
15.
Opt Express ; 28(10): 15601-15610, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403584

RESUMO

Manipulating circularly polarized (CP) light waves at will are highly important for photonic researches and applications. Recently, while Pancharatnam-Berry (PB) metasurfaces have shown unprecedented capabilities to control CP light, meta-devices constructed so far always suffer from the limitations of low-efficiency and narrow bandwidth. Here, we propose a scheme to construct PB metasurfaces with these two issues well addressed. To verify our idea, two PB meta-devices are designed and fabricated for achieving high-efficiency and broadband photonic spin Hall effect and focusing effect, respectively. Experimental results, in good agreement with full wave simulations, demonstrate the desired functionalities with efficiencies reaching 80% within an ultra-wide frequency band (8.2-17.3GHz). The proposed design scheme is generic and can be extended to high-frequency regimes. Our work can stimulate the realizations of high-performance and broadband PB meta-devices with diversified functionalities.

16.
J Environ Sci (China) ; 95: 190-200, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32653179

RESUMO

Atmospheric volatile organic compounds (VOCs) were observed by an on-line gas chromatography-flame ionization detector monitoring system from November 2016 to August 2017 in Beijing. The average concentrations were winter (40.27 ± 25.25 µg/m3) > autumn (34.25 ± 19.90 µg/m3) > summer (32.53 ± 17.39 µg/m3) > spring (24.72 ± 17.22 µg/m3). Although benzene (15.70%), propane (11.02%), ethane (9.32%) and n-butane (6.77%) were the most abundant species, ethylene (14.07%) and propene (11.20%) were the key reactive species to ozone formation potential (OFP), and benzene, toluene, ethylbenzene, m-xylene + p-xylene and o-xylene (54.13%) were the most reactive species to secondary organic aerosol formation potential (SOAFP). The diurnal and seasonal variations indicated that diesel vehicle emission during early morning, gasoline vehicle emission at the traffic rush hours and coal burning during the heating period might be important sources. Five major sources were further identified by positive matrix factorization (PMF). The vehicle exhaust (gasoline exhaust and diesel exhaust) was found to be contributed most to atmospheric VOCs, with 43.59%, 41.91%, 50.45% and 43.91%, respectively in spring, summer, autumn and winter; while solvent usage contributed least, with 11.10%, 7.13%, 14.00% and 19.87%, respectively. Biogenic emission sources (13.11%) were only identified in summer. However, both vehicle exhaust and solvent usage were identified to be the key sources considering contributions to the OFP and SOAFP. Besides, the contributions of combustion during heating period and gasoline evaporation source during warm seasons to OFP and SOAFP should not be overlooked.


Assuntos
Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , Pequim , China , Monitoramento Ambiental , Emissões de Veículos/análise
17.
Angew Chem Int Ed Engl ; 59(46): 20411-20416, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-32743842

RESUMO

Efforts have been devoted to achieving a highly efficient artificial synthesis of ammonia (NH3 ). Reported herein is a novel Fe-MoS2 catalyst with Fe atomically dispersed onto MoS2 nanosheets, imitating natural nitrogenase, to boost N2 electroreduction into NH3 at room temperature. The Fe-MoS2 nanosheets exhibited a faradic efficiency of 18.8 % with a yield rate of 8.63 µg NH 3 mgcat. -1 h-1 for NH3 at -0.3 V versus the reversible hydrogen electrode. The mechanism study revealed that the electroreduction of N2 was promoted and the competing hydrogen evolution reaction was suppressed by decorating the edge sites of S in MoS2 with the atomically dispersed Fe, resulting in high catalytic performance for the electroreduction of N2 into NH3 . This work provides new ideas for the design of catalysts for N2 electroreduction and strengthens the understanding about N2 activation over Mo-based catalysts.

18.
J Natl Compr Canc Netw ; 17(1): 22-28, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30659126

RESUMO

Background: Bisphosphonates reduce skeletal-related events (SREs) in patients with multiple myeloma (MM) and, in some studies, improved survival. Since 2011, bisphosphonate use has been recommended by NCCN for all patients with newly diagnosed MM receiving antineoplastic therapy independent of the presence of bone disease. This study investigated their use after these guidelines were established. Methods: We identified patients aged ≥65 years in the SEER-Medicare database with newly diagnosed MM between January 1, 2012, and December 31, 2013, who received antineoplastic therapy, had ≥6 months of follow-up, and did not receive prior bisphosphonates. Presence of SREs at diagnosis was identified, including pathologic fracture, spinal cord compression, radiation to bone, or surgery to bone. Use of bisphosphonates was defined as having ≥1 claim for an intravenous or oral bisphosphonate within 6 months after the start of antineoplastic therapy. We used multivariable modeling to compare users with nonusers, controlling for demographic and clinical covariates. We compared overall survival between users and nonusers using proportional hazards analysis. Results: Of 1,309 patients identified, 720 (55%) used a bisphosphonate. Factors associated with use included SRE at diagnosis (adjusted odds ratio [AOR], 2.60; 95% CI, 1.98-3.40), hypercalcemia (AOR, 1.74; 95% CI, 1.26-2.41), and use of proteasome inhibitor + immunomodulatory imide therapy (AOR, 1.70; 95% CI, 1.21-2.39). Chronic kidney disease (AOR, 0.48; 95% CI, 0.35-0.66) was associated with decreased use. Bisphosphonate use was associated with reduced mortality (hazard ratio, 0.70; 95% CI, 0.56-0.88). Conclusions: Although bisphosphonate use is recommended for all patients with newly diagnosed MM receiving antineoplastic therapy, 45% of patients in the United States did not receive this guideline-recommended care.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Doenças Ósseas/prevenção & controle , Mieloma Múltiplo/complicações , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/normas , Doenças Ósseas/epidemiologia , Doenças Ósseas/etiologia , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Medicare/estatística & dados numéricos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Pamidronato/uso terapêutico , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , Programa de SEER/estatística & dados numéricos , Resultado do Tratamento , Estados Unidos/epidemiologia , Ácido Zoledrônico/uso terapêutico
19.
Environ Geochem Health ; 41(1): 297-308, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29948539

RESUMO

Using sodium alginate hydrogel as skeleton, in combination with chitosan and magnetic Fe3O4, a new type of magnetic chitosan/sodium alginate gel bead (MCSB) was prepared. Adsorptive removal of Cu(II) from aqueous solutions was studied by using the MCSB as a promising candidate in environmental application. Different kinetics and isotherm models were employed to investigate the adsorption process. Based on Fourier transform infrared spectroscopy, field-emission scanning electron microscope, CHNS/O elements analysis, vibration magnetometer, and various means of characterization, a comprehensive analysis of the adsorption mechanism was conducted. The MCSB had a good magnetic performance with a saturation magnetization of 12.5 emu/g. Elemental analysis proved that the addition of chitosan introduced a considerable amount of nitrogen-rich groups, contributing significantly to copper adsorption onto gel beads. The contact time necessary for adsorption was optimized at 120 min to achieve equilibrium. Experimental data showed that the adsorption process agreed well with the Langmuir isotherm model and the pseudo-second-order kinetics model. The theoretical maximum adsorption capacity of MCSB for Cu(II) could reach as high as 124.53 mg/g. In conclusion, the MCSB in this study is a novel and promising composite adsorbent, which can be applied for practical applications in due course.


Assuntos
Alginatos/química , Quitosana/química , Cobre/isolamento & purificação , Nanosferas/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Nanosferas/ultraestrutura , Termodinâmica
20.
J Environ Sci (China) ; 71: 150-167, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30195674

RESUMO

Continuous observation of isoprene, α-pinene and ß-pinene was carried out in a typical urban area of Beijing from March 2014 to February 2015, using an AirmoVOC online analyzer. Based on the analysis of the ambient level and variation characteristics of isoprene, α-pinene and ß-pinene, the chemical reactivity was studied, and their sources were identified. Results showed that the concentrations of isoprene, α-pinene and ß-pinene in the urban area of Beijing were lower than those in richly vegetated areas; the concentrations of isoprene were at a moderate level compared with those of previous studies of Beijing. Concentrations of isoprene, α-pinene and ß-pinene showed different seasonal, monthly, daily and diurnal variations, and all of the three species showed higher level at night than those in the daytime as a whole, the variations of isoprene, α-pinene and ß-pinene mainly influenced by emission of sources, photochemical reaction, and meteorological parameters. Isoprene was the largest contributor to the total OFP values than α-pinene and ß-pinene. α-Pinene was the largest contributor to the total SOAFP values than isoprene and ß-pinene in autumn, while isoprene was the largest one in other seasons. Isoprene, α-pinene and ß-pinene were derived mainly from biological sources; and α-pinene level were also affected by industrial sources. To reduce the concentrations of isoprene, α-pinene and ß-pinene, it is necessary to scientifically select urban green plant species, and more strict control measures should be taken to reduce the emission of α-pinene from industrial sources, such as artificial flavors and resins synthesis processes.


Assuntos
Poluentes Atmosféricos/análise , Butadienos/análise , Monitoramento Ambiental , Hemiterpenos/análise , Pentanos/análise , Poluição do Ar/estatística & dados numéricos , Atmosfera/química , Pequim
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