Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.329
Filtrar
1.
Chemosphere ; 250: 126275, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32113091

RESUMO

Innovative iron/calcium in-situ-impregnated mesoporous activated carbons (GL100 and GL200) have been prepared by iron/calcium in-situ-impregnation and Multistage Depth-Activation. Arsenic adsorption kinetics, isotherms, thermodynamics, and re-usability were investigated. Effects of surface-absorbed (ST-HA) and dissolved states humic acid (DHA) on the arsenic adsorption were also determined. Results suggested in-situ iron/calcium impregnation caused the well-development of mesoporous structures during ranges of 2.0-5.0 nm in GL100 and 5.0-50 nm in GL200, respectively. The increase of iron/calcium ensured surface basicity and high ash contents on GL100/GL200, and As(III)/As(V) can be better adsorbed in neutral conditions with higher kinetics in comparison with regular mesoporous carbon XHIT. Maximum adsorption capacities of As(III)/As(V) by GL100 and GL200 were 2.985/3.385 mg/g and 2.516/2.807 mg/g, respectively. Arsenic desorption and carbon re-usability of GL100/200 was improved. As(III)(As (V)) adsorption capacities by GL100 and GL200 were 2.437(1.672) mg/g and 1.740(1.308) mg/g, respectively, after eight cycles. Arsenic adsorption capacities on GL100 were proved to be promoted with the presence of low-level of ST-HA or DHA, and be inhibited at a high-level. As(V) was bound more strongly than As(III) in the presence of ST-HA. As(III)/As(V) uptakes increased slightly and decrease gradually to 1.75/1.86 mg/g in the presence of DHA (0-10 mg DOC/L). Physisorption and chemisorption mechanisms dominant in arsenic adsorption on GL100 in presence of humic acid, forming inner-sphere complexation with metallic oxide, functional groups on carbon surface and humic acid structure, or ternary surface complexation via cationic metal ions as cation bridge.

2.
BMC Geriatr ; 20(1): 91, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32138691

RESUMO

BACKGROUND: Declines in health, physical, cognitive, and mental function with age suggest a lower level of health-related quality of life (HRQoL) in late life; however, previous studies found that the associations were weak and varied, depending on the study designs and cohort characteristics. METHODS: The present study examined the paradox of aging in an East Asian context by regressing the age patterns of objective health indicators (physical, cognitive, and mental function), and subjective HRQoL (12-item Short Form, SF-12), on the independent and interactive effects of age and physical function in a cohort study of 5022 community-dwelling adults aged 55 and older in Taiwan. RESULTS: Age patterns differed across measures. The SF-12 mental health score (MCS) showed a slight positive association with age and this effect remained stable after controlling for various age-related covariates. The SF-12 physical health score (PCS), in turn, was negatively associated with age. Age differences in PCS were fully explained by age decrements in objective physical health. However, consistent with the so-called paradox of aging, the association between objective and subjective physical health weakened with age. CONCLUSION: These findings add to prior evidence indicating that - in spite of objective health decrements - subjective HRQoL is maintained in later life among Asian Chinese. Also, these paradoxical patterns appear to vary for mental and physical components of HRQoL, and future research is needed to explore the underlying mechanism. TRIAL REGISTRATION: Healthy Aging Longitudinal Study in Taiwan (HALST) is retrospectively registered at ClinicalTrials.gov on January 24, 2016 with trial registration number NCT02677831.

3.
Nano Lett ; 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32125868

RESUMO

Developing efficient charge separation strategies is essential to achieve high-power conversion efficiency in the fields of chemistry, biology, and material science. Herein, we develop a facile strategy for fabrication of unique wafer-scale radial nanowire assemblies by exploiting shear force in rotary solution. The assembly mechanism can be well revealed by the large-scale stochastic dynamics simulation. Free electrons can be rapidly generated to produce quantitatively tunable current output when the radial nanowire assemblies rotate under the magnetic field. Moreover, the photoconductive performance of the radial semiconductor nanowire assemblies can be remarkably enhanced as the electron-hole recombination was retrained by the efficient charge separation under the rotating magnetic field. Such large-scale unique nanowire assemblies will facilitate the design of an efficient charge separation process in biosystem, sensors, and photocatalysis.

4.
Nat Commun ; 11(1): 1178, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32132530

RESUMO

Targeted insertion of transgenes at pre-determined plant genomic safe harbors provides a desirable alternative to insertions at random sites achieved through conventional methods. Most existing cases of targeted gene insertion in plants have either relied on the presence of a selectable marker gene in the insertion cassette or occurred at low frequency with relatively small DNA fragments (<1.8 kb). Here, we report the use of an optimized CRISPR-Cas9-based method to achieve the targeted insertion of a 5.2 kb carotenoid biosynthesis cassette at two genomic safe harbors in rice. We obtain marker-free rice plants with high carotenoid content in the seeds and no detectable penalty in morphology or yield. Whole-genome sequencing reveals the absence of off-target mutations by Cas9 in the engineered plants. These results demonstrate targeted gene insertion of marker-free DNA in rice using CRISPR-Cas9 genome editing, and offer a promising strategy for genetic improvement of rice and other crops.

5.
J Infect Dis ; 221(Supplement_2): S139-S147, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32176789

RESUMO

BACKGROUND: Candidemia is the most common, serious fungal infection and Candida antifungal resistance is a challenge. We report recent surveillance of candidemia in China. METHODS: The study encompassed 77 Chinese hospitals over 3 years. Identification of Candida species was by mass spectrometry and DNA sequencing. Antifungal susceptibility was determined using the Clinical and Laboratory Standards Institute broth microdilution method. RESULTS: In total, 4010 isolates were collected from candidemia patients. Although C. albicans was the most common species, non-albicans Candida species accounted for over two-thirds of isolates, predominated C. parapsilosis complex (27.1%), C. tropicalis (18.7%), and C. glabrata complex (12.0%). Most C. albicans and C. parapsilosis complex isolates were susceptible to all antifungal agents (resistance rate <5%). However, there was a decrease in voriconazole susceptibility to C. glabrata sensu stricto over the 3 years and fluconazole resistance rate in C. tropicalis tripled. Amongst less common Candida species, over one-third of C. pelliculosa isolates were coresistant to fluconazole and 5-flucytocine, and >56% of C. haemulonii isolates were multidrug resistance. CONCLUSIONS: Non-albicans Candida species are the predominant cause of candidemia in China. Azole resistance is notable amongst C. tropicalis and C. glabrata. Coresistance and multidrug resistance has emerged in less common Candida species.

6.
Mater Sci Eng C Mater Biol Appl ; 110: 110708, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32204020

RESUMO

Magnetic fibrous membrane used to generate heat under the alternating magnetic field (AMF) has attracted wide attention due to their application in magnetic hyperthermia. However, there is not magnetic fibrous membrane prepared by melt electrospinning (e-spinning) which is a solvent-free, bio-friendly technology. In this work, polycaprolactone (PCL)/Fe3O4 fiber membrane was prepared by melt e-spinning and using homemade self-powered portable melt e-spinning apparatus. The hand-held melt e-spinning apparatus has a weight of about 450 g and a precise size of 24 cm in length, 6 cm in thickness and 13 cm in height, which is more portable for widely using in the medical field. The PCL/Fe3O4 composite fibers with diameters of 4-17 µm, are very uniform. In addition, the magnetic composite fiber membrane has excellent heating efficiency and thermal cycling characteristics. The results indicated that self-powered portable melt e-spinning apparatus and PCL/Fe3O4 fiber membrane may provide an attractive way for hyperthermia therapy.

7.
J Am Chem Soc ; 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32176485

RESUMO

Selective and efficient catalytic conversion of carbon dioxide (CO2) into value-added fuels and feedstocks provides an ideal avenue to high-density renewable energy storage. An impediment to enabling deep CO2 reduction to oxygenates and hydrocarbons (e.g., C2+ compounds) is the difficulty of coupling carbon-carbon bonds efficiently. Copper in the +1 oxidation state has been thought to be active for catalyzing C2+ formation, whereas it is prone to being reduced to Cu0 at cathodic potentials. Here we report that catalysts with nanocavities can confine carbon intermediates formed in situ, which in turn covers the local catalyst surface and thereby stabilizes Cu+ species. Experimental measurements on multihollow cuprous oxide catalyst exhibit a C2+ Faradaic efficiency of 75.2 ± 2.7% at a C2+ partial current density of 267 ± 13 mA cm-2 and a large C2+-to-C1 ratio of ∼7.2. Operando Raman spectra, in conjunction with X-ray absorption studies, confirm that Cu+ species in the as-designed catalyst are well retained during CO2 reduction, which leads to the marked C2+ selectivity at a large conversion rate.

8.
Environ Res ; 183: 109197, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32058142

RESUMO

There is a large body of evidence linking Environmental Tobacco Smoke (ETS) exposure with impaired lung function. However, it is not known whether exposure to pets modifies this relationship. To investigate if pet ownership changes the association between ETS exposure and lung function, a population-based sample of 7326 children, 7-14 years old, were randomly recruited from 24 districts in northeast China. Lung function including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), peak expiratory flow (PEF), and maximal mid-expiratory flow (MMEF) was measured by spirometry, while pet ownership time periods and ETS exposure were collected by questionnaire. Two-level regression analysis was done, with covariates controlled for. The results showed pet exposure in certain early lifetime windows modified the associations of ETS exposure on decreased lung function in children. Among children exposed to current ETS, those exposed to pets in utero had greater reductions in lung function (for instance: OR for reduced FVC (<85% predicted) = 10.86; 95% CI: 3.80-30.97) than those not exposed to pets in utero (OR = 2.32; 95% CI: 1.76-3.05) (pinteraction = 0.005). While, children exposed to current pet ownership reduced the lung function impairment induced by ETS exposure during the first 2 years of life and/or ETS exposure during pregnancy, especially for FVC impairment. For instance, OR (95%CI) for reduced FVC (<85% predicted) was 0.81 (0.56, 1.18) and 1.42 (1.15, 1.74), respectively, for children with or without current pet ownership exposed to ETS during the first 2 years of life (pinteraction = 0.010). Furthermore, pet type or number of pets did not significantly modify associations between ETS exposure and lung function. In conclusion, the timing of pet ownership modified associations between ETS exposure and lung function, pet ownership in utero and during the first 2 years of life significantly worsened the adverse impacts of passive smoking on lung function.

9.
Biomed Environ Sci ; 33(1): 37-47, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32029057

RESUMO

Objective: To evaluate the effects of incretin-based therapies on body weight as the primary outcome, as well as on body mass index (BMI) and waist circumference (WC) as secondary outcomes. Methods: Databases including Medline, Embase, the Cochrane Library, and clinicaltrials.gov (www.clinicaltrials.gov) were searched for randomized controlled trials (RCTs). Standard pairwise meta-analysis and network meta-analysis (NMA) were both carried out. The risk of bias (ROB) tool recommended by the Cochrane handbook was used to assess the quality of studies. Subgroup analysis, sensitivity analysis, meta-regression, and quality evaluation based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) were also performed. Results: A total of 292 trials were included in this study. Compared with placebo, dipeptidyl-peptidase IV inhibitors (DPP-4Is) increased weight slightly by 0.31 kg [95% confidence interval ( CI): 0.05, 0.58] and had negligible effects on BMI and WC. Compared with placebo, glucagon-like peptide-1 receptor agonists (GLP-1 RAs) lowered weight, BMI, and WC by -1.34 kg (95% CI: -1.60, -1.09), -1.10 kg/m 2 (95% CI: -1.42, -0.78), and -1.28 cm (95% CI: -1.69, -0.86), respectively. Conclusion: GLP-1 RAs were more effective than DPP-4Is in lowering the three indicators. Overall, the effects of GLP-1 RAs on weight, BMI, and WC were favorable.

10.
Environ Pollut ; 259: 113857, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31918137

RESUMO

Previous epidemiological and experimental studies have shown that legacy perfluoroalkyl acids (PFAAs) are immunotoxic. However, whether the immunosuppressive effects in PFAA alternatives which recently have been widely detected in the environment are unknown. To address this knowledge gap, we investigated the relationship of serum legacy PFAAs and PFAA alternatives with the antibody of hepatitis B virus in adults. We recruited 605 participants from a cross-sectional study, the Isomer of C8 Health Project in China. We measured two representative legacy PFAAs (perfluorooctane sulfonate, PFOS and perfluorooctanoic acid, PFOA), and three PFAA alternatives (two chlorinated polyfluorinated ether sulfonic acids, Cl-PFESAs and perfluorobutanoic acid, PFBA) in serum using ultra-performance liquid chromatograph-tandem mass spectrometry (UPLC-MS/MS). We applied linear and logistic regression models to analyze associations between serum PFAAs and hepatitis B surface antibody (HBsAb) with multivariable adjustments. We found negative associations between serum PFAAs concentrations and HBsAb. Lower serum HBsAb levels (log mIU/mL) were observed for each log-unit increase in linear PFOS (ß = -0.31, 95% confidential interval: 0.84, -0.18), 6:2 PFESA (ß = -0.81, 95% CI: 1.20, -0.42), 8:2 PFESA (ß = -0.29, 95% CI: 0.43, -0.14) and PFBA (ß = -0.18, 95% CI: 0.28, -0.08). The association between PFAAs and HBsAb seronegative seemed to be higher for 6:2 PFESA (odds ratio = 3.32, 95% CI: 2.16, 5.10) than its predecessors, linear PFOS (OR = 1.96, 95% CI: 1.37, 2.81) and branched PFOS isomers (OR = 1.64, 95% CI: 1.05, 2.56). We report new evidence that exposure to PFAA alternatives are associated with lower HBsAb in adults. This association seems to be stronger in 6:2 PFESA than PFOS. Our results suggest that more studies are needed to clarify the potential toxicity of PFAA alternatives in human which will facilitate better chemical regulations for PFAAs.

12.
Fitoterapia ; 142: 104471, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31917302

RESUMO

Three new thiophene derivatives, ecliprostins A-C (1-3), have been isolated from the aerial parts of a Compositae medicinal plant Eclipta prostrata, and structures of them have been elucidated by comprehensive spectroscopic analyses. Both ecliprostins A (1) and B (2) feature an acetylenic bithiophenyl backbone and also incorporate an isovalerate moiety, while ecliprostin C (3) is a symmetrical dimer of compound 1 and represents the first example bonded via an ether bridge among the very limited natural dimers. All three compounds show antibacterial activity against Staphylococcus aureus.

14.
J Neuroinflammation ; 17(1): 11, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915018

RESUMO

BACKGROUND: Emerging evidence indicates that inflammasome-induced inflammation plays a crucial role in the pathogenesis of Parkinson's disease (PD). Several proteins including α-synuclein trigger the activation of NLRP3 inflammasome. However, few studies examined whether inflammasomes are activated in the periphery of PD patients and their possible value in the diagnosis or tracking of the progress of PD. The aim of this study was to determine the association between inflammasome-induced inflammation and clinical features in PD. METHODS: There were a total of 67 participants, including 43 patients with PD and 24 controls, in the study. Participants received a complete evaluation of motor and non-motor symptoms, including Hoehn and Yahr (H-Y) staging scale. Blood samples were collected from all participants. The protein and mRNA expression levels of inflammasomes subtypes and components in peripheral blood mononuclear cells (PBMCs) were determined using western blotting and RT-qPCR. We applied Meso Scale Discovery (MSD) immunoassay to measure the plasma levels of IL-1ß and α-synuclein. RESULTS: We observed increased gene expression of NLRP3, ASC, and caspase-1 in PBMCs, and increased protein levels of NLRP3, caspase-1, and IL-1ß in PD patients. Plasma levels of IL-1ß were significantly higher in patients with PD compared with controls and have a positive correlation with H-Y stage and UPDRS part III scores. Furthermore, plasma α-synuclein levels were also increased in PD patients and have a positive correlation with both UPDRS part III scores and plasma IL-1ß levels. CONCLUSIONS: Our data demonstrated that the NLRP3 inflammasome is activated in the PBMCs from PD patients. The related inflammatory cytokine IL-1ß and total α-synuclein in plasma were increased in PD patients than controls, and both of them presented a positive correlation with motor severity in patients with PD. Furthermore, plasma α-synuclein levels have a positive correlation with IL-1ß levels in PD patients. All these findings suggested that the NLRP3 inflammasome activation-related cytokine IL-1ß and α-synuclein could serve as non-invasive biomarkers to monitor the severity and progression of PD in regard to motor function.

15.
ACS Nano ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31999429

RESUMO

The development of highly efficient electrocatalysts to reduce overpotentials is vital for accelerating the sluggish oxygen evolution reaction (OER) processes. Herein, we demonstrate ultrathin heterogeneous nanosheets as a promising OER electrocatalyst, which are composed of ultrafine CoFeOx nanoparticles and a monolayered CoN4-based metal-organic framework (MOF) matrix. The embedding of such inorganic nanoparticles in the MOF lattice creates metal Co sites located at the CoFeOx/MOF interfaces. Structural characterization and analysis indicated a higher valence and changed 3d electronic configuration for the interfacial Co in contrast to the CoN4 sites. Furthermore, theoretical calculations reveal the high activity of interfacial Co sites for OER. Electrochemical studies confirm that the ultrathin heterogeneous nanosheets deposited on carbon cloth can achieve an excellent electrocatalytic OER performance with a low overpotential of 232 mV at a current density of 10 mA cm-2 with good stability. This work provides insights on the development of ultrathin OER heterocatalysts with highly active interfaces of inorganic units and MOFs.

16.
Nat Nanotechnol ; 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959929

RESUMO

Chirality-the property of an object wherein it is distinguishable from its mirror image-is of widespread interest in chemistry and biology1-6. Regioselective magnetization of one-dimensional semiconductors enables anisotropic magnetism at room temperature, as well as the manipulation of spin polarization-the properties essential for spintronics and quantum computing technology7. To enable oriented magneto-optical functionalities, the growth of magnetic units has to be achieved at targeted locations on a parent nanorod. However, this challenge is yet to be addressed in the case of materials with a large lattice mismatch. Here, we report the regioselective magnetization of nanorods independent of lattice mismatch via buffer intermediate catalytic layers that modify interfacial energetics and promote regioselective growth of otherwise incompatible materials. Using this strategy, we combine materials with distinct lattices, chemical compositions and magnetic properties, that is, a magnetic component (Fe3O4) and a series of semiconducting nanorods absorbing across the ultraviolet and visible spectrum at specific locations. The resulting heteronanorods exhibit optical activity as induced by the location-specific magnetic field. The regioselective magnetization strategy presented here enables a path to designing optically active nanomaterials for chirality and spintronics.

17.
Zhongguo Zhen Jiu ; 40(1): 49-53, 2020 Jan 12.
Artigo em Chinês | MEDLINE | ID: mdl-31930899

RESUMO

OBJECTIVE: To explore the epidemiologic characteristics of acupuncturists who are sensitive to stimulation of moxa smoke, which could provide further direction for safety protection of exerting moxibustion and to further verify the feasibility of internet survey. METHODS: A self-made questionnaire regarding body response to moxa smoke was established, which was used to conduct a face-to-face survey among acupuncturists who had performed long-term moxibustion. The Logistic regression model was used to analyze the factors affecting the stimulation response of acupuncturists and the epidemiological characteristics of acupuncturists was obtained. RESULTS: A total of 733 valid data was obtained. The multivariate Logistic regression analysis showed that the history of chronic respiratory disease was the main risk factor of stimulus response including cough, phlegm in the throat, asthma, dyspnea, shortness of breath and nasal dryness after exposure to moxa smoke (P<0.05, P<0.01). The risk of stimulus response such as cough, tearing and nasal dryness was higher in women than in men (P<0.05, P<0.01). The risk of dry eyes and eyes pain in smokers was higher than those in non-smokers (P<0.05). The risk of shortness of breath in those who were exposed to second-hand smoke was higher than those who were not exposed to second-hand smoke (P<0.05). The analysis of index trend line showed that the results of internet survey were similar to those of face-to-face survey. CONCLUSION: The stimulus response of acupuncturist after long-term exposure to moxa smoke is related to the history of chronic respiratory disease, being female, smoking or exposure of second-hand smoke, therefore more attention should be paid to those populations. In addition, the internet survey can be used for the epidemiological investigation of safety of moxa smoke.


Assuntos
Moxibustão , Fumaça , Tosse , Feminino , Humanos , Masculino , Muco , Inquéritos e Questionários
18.
Artigo em Inglês | MEDLINE | ID: mdl-31970642

RESUMO

Vegetation plays an important role in the energy exchange, water cycle, carbon cycle, biogeochemical cycle, and maintenance of surface ecosystems. In recent years, regional vegetation cover has changed significantly. This study used statistical analyses, including the Mann-Kendall trend test, the Hurst exponent, and Pettitt test, to analyze the characteristics of temporal and spatial variation of vegetation coverage in the Xijiang River basin from 2000 to 2013. The results showed that vegetation coverage of 98.76% of the Xijiang River basin is weakly variable (Cv < 0.1). The area with significantly increased vegetation accounts for 43.45% of the total area (p < = 0.05). A total of 19.47% of vegetation coverage in the Xijiang River basin had significant change-points from 2004 to 2008 (p < = 0.05), and the area of concave change-points accounted for 25.99% of the total area of point increased the vegetation coverage. At an altitude of 500-2000 m, the altitude has an inhibitory effect on vegetation coverage. When the slope is less than 35 degrees, the slope has a promoting effect on vegetation coverage. Rich precipitation resources are the main source of soil water supply, and higher temperature provides better thermal energy resources, which may have a significant impact on vegetation growth in the future and cause time lag effects of climatic factors on vegetation coverage. The vegetation coverage and the area affected by the precipitation and temperature (time lag factors) accounted for 32.99% and 31.47% of the total watershed, respectively. The correlation between climatic factors, topographic factors, and vegetation coverage increased over time. The results from this study will help to further deepen the understanding of vegetation cover and its influencing factors, and provide a scientific basis for ecological restoration projects such as vegetation restoration in the Xijiang River basin of China.

19.
Sci Total Environ ; 712: 136495, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31945536

RESUMO

Long-term overgrazing tends to cause soil phosphorus (P) deficiency in grasslands. The relationships between grazing-induced shifts in species composition and root traits associated with P acquisition involved in these shifts remain unknown. Species vary in their P-acquisition strategies, and we hypothesize that species that acquire P more efficiently are better adapted to overgrazing. We measured relative biomass, root physiological activities (e.g., rhizosheath acid phosphatase activity (Apase), and leaf manganese concentration ([Mn]) as a proxy for carboxylate concentrations in rhizosheath) and morphological traits (e.g., specific root length) of six common species in a field experiment conducted in a typical steppe of Inner Mongolia. There were two exclosure demonstration plots, i.e. exclosed since 1983 and 1996, and long-term free grazing without exclosure of sheep. Long-term overgrazing caused a reduction in bulk soil Olsen P concentration and increased community-weighted leaf nitrogen: P ratio by 27% and 37%, respectively, indicating more severe P limitation for steppe vegetation. Carex duriuscula exhibited an inherently greater specific root length, proportion of fine roots and rhizosheath Apase than other species did in both exclosure and grazing treatments. Cleistogenes squarrosa showed a greater leaf [Mn] induced by overgrazing. The increased dominance of C. duriuscula and C. squarrosa was positively correlated with finer roots, greater rhizosheath Apase or carboxylate release under long-term overgrazing. Species that had inefficient root traits for P acquisition (e.g., low specific root length and low leaf [Mn]), i.e. Stipa grandis, exhibited a decreased dominance in response to overgrazing. Dominance of species did not change under grazing which may be related to either relatively inefficient inherent morphological (i.e. in Artemisia frigida) or physiological traits (i.e. in Leymus chinensis and Agropyron michnoi) for P acquisition. Our study highlights the importance of acknowledging root traits involved in efficient P acquisition for theories on community succession induced by overgrazing.

20.
Clin Ther ; 42(2): 338-350.e4, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31937461

RESUMO

PURPOSE: Several epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) were firmly established as front-line treatment for non-small cell lung cancer (NSCLC) that harbored an activating EGFR mutation. Gefitinib or erlotinib was considered the standard of care. TKI-based combination therapy has been investigated and has shown encouraging results. METHODS: The PubMed and EMBASE databases, the Cochrane Central Register of Controlled Trials, and meeting abstracts were screened for relevant studies between January 2000 and February 2019. Prospective randomized controlled trials were included that investigated EGFR TKIs (alone or in combination) in untreated patients with NSCLC whose tumors had sensitive EGFR mutations. A frequentist random effects network meta-analysis model was conducted to assess objective response rate, progression-free survival, and overall survival. P-score was used to rank treatment effects. FINDINGS: Seventeen trials involving 9 treatments and 4373 patients were included. Heterogeneity existed in the network analysis. For progression-free survival, the top 3 treatments were osimertinib, standard of care plus chemotherapy, and standard of care plus bevacizumab; corresponding p-scores were 0.88, 0.79, and 0.75, respectively. For overall survival, the top 3 treatments were standard of care plus chemotherapy, osimertinib, and dacomitinib; corresponding p-scores were 0.89, 0.85, and 0.64. TKI-based combination therapy caused more toxicity than a TKI alone. IMPLICATIONS: Osimertinib seemed to be a better option as upfront therapy for EGFR-mutant NSCLC in terms of efficacy and tolerability.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA