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1.
N Engl J Med ; 386(22): 2097-2111, 2022 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-35507481

RESUMEN

BACKGROUND: The ZF2001 vaccine, which contains a dimeric form of the receptor-binding domain of severe acute respiratory syndrome coronavirus 2 and aluminum hydroxide as an adjuvant, was shown to be safe, with an acceptable side-effect profile, and immunogenic in adults in phase 1 and 2 clinical trials. METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 3 trial to investigate the efficacy and confirm the safety of ZF2001. The trial was performed at 31 clinical centers across Uzbekistan, Indonesia, Pakistan, and Ecuador; an additional center in China was included in the safety analysis only. Adult participants (≥18 years of age) were randomly assigned in a 1:1 ratio to receive a total of three 25-µg doses (30 days apart) of ZF2001 or placebo. The primary end point was the occurrence of symptomatic coronavirus disease 2019 (Covid-19), as confirmed on polymerase-chain-reaction assay, at least 7 days after receipt of the third dose. A key secondary efficacy end point was the occurrence of severe-to-critical Covid-19 (including Covid-19-related death) at least 7 days after receipt of the third dose. RESULTS: Between December 12, 2020, and December 15, 2021, a total of 28,873 participants received at least one dose of ZF2001 or placebo and were included in the safety analysis; 25,193 participants who had completed the three-dose regimen, for whom there were approximately 6 months of follow-up data, were included in the updated primary efficacy analysis that was conducted at the second data cutoff date of December 15, 2021. In the updated analysis, primary end-point cases were reported in 158 of 12,625 participants in the ZF2001 group and in 580 of 12,568 participants in the placebo group, for a vaccine efficacy of 75.7% (95% confidence interval [CI], 71.0 to 79.8). Severe-to-critical Covid-19 occurred in 6 participants in the ZF2001 group and in 43 in the placebo group, for a vaccine efficacy of 87.6% (95% CI, 70.6 to 95.7); Covid-19-related death occurred in 2 and 12 participants, respectively, for a vaccine efficacy of 86.5% (95% CI, 38.9 to 98.5). The incidence of adverse events and serious adverse events was balanced in the two groups, and there were no vaccine-related deaths. Most adverse reactions (98.5%) were of grade 1 or 2. CONCLUSIONS: In a large cohort of adults, the ZF2001 vaccine was shown to be safe and effective against symptomatic and severe-to-critical Covid-19 for at least 6 months after full vaccination. (Funded by the National Science and Technology Major Project and others; ClinicalTrials.gov number, NCT04646590.).


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Vacunas de Subunidad , Adolescente , Adulto , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/uso terapéutico , Método Doble Ciego , Humanos , SARS-CoV-2 , Vacunación , Vacunas , Vacunas de Subunidad/efectos adversos , Vacunas de Subunidad/uso terapéutico , Adulto Joven
2.
Proc Natl Acad Sci U S A ; 119(11): e2122954119, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35238654

RESUMEN

SignificanceSARS-CoV-2 continues to evolve through emerging variants, more frequently observed with higher transmissibility. Despite the wide application of vaccines and antibodies, the selection pressure on the Spike protein may lead to further evolution of variants that include mutations that can evade immune response. To catch up with the virus's evolution, we introduced a deep learning approach to redesign the complementarity-determining regions (CDRs) to target multiple virus variants and obtained an antibody that broadly neutralizes SARS-CoV-2 variants.


Asunto(s)
Anticuerpos ampliamente neutralizantes/inmunología , COVID-19/inmunología , SARS-CoV-2/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Anticuerpos ampliamente neutralizantes/farmacología , Vacunas contra la COVID-19/inmunología , Regiones Determinantes de Complementariedad , Aprendizaje Profundo , Epítopos/inmunología , Humanos , Inmunoterapia/métodos , Pruebas de Neutralización/métodos , Dominios Proteicos , SARS-CoV-2/patogenicidad , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología
3.
Brief Bioinform ; 23(5)2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36070863

RESUMEN

Computational recovery of gene regulatory network (GRN) has recently undergone a great shift from bulk-cell towards designing algorithms targeting single-cell data. In this work, we investigate whether the widely available bulk-cell data could be leveraged to assist the GRN predictions for single cells. We infer cell-type-specific GRNs from both the single-cell RNA sequencing data and the generic GRN derived from the bulk cells by constructing a weakly supervised learning framework based on the axial transformer. We verify our assumption that the bulk-cell transcriptomic data are a valuable resource, which could improve the prediction of single-cell GRN by conducting extensive experiments. Our GRN-transformer achieves the state-of-the-art prediction accuracy in comparison to existing supervised and unsupervised approaches. In addition, we show that our method can identify important transcription factors and potential regulations for Alzheimer's disease risk genes by using the predicted GRN. Availability: The implementation of GRN-transformer is available at https://github.com/HantaoShu/GRN-Transformer.


Asunto(s)
Biología Computacional , Redes Reguladoras de Genes , Algoritmos , Biología Computacional/métodos , Factores de Transcripción/genética , Transcriptoma
4.
Opt Express ; 32(10): 16879-16890, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38858884

RESUMEN

In this paper, a polarization-insensitive high transmittance bandpass filter with low radar cross section (RCS) in both S- and X-band is proposed. This is the first study to use the partition layout loading approach for conformal structures with transmissive windows, reducing the operating band RCS. Curved structures have stronger radiation at a smaller angle to the incident wave, and that is how their scattering differs from uniform scattering from flat structures. The structure is divided by analyzing the radiative contribution of different regions. The surface was discussed in regions according to surface angles, and a new partition layout loading method was used to suppress the side currents and decreased backward scattering, achieving a backward RCS reduction of more than 10 dB at 4-8 GHz (66.7%). The bandpass layer operating at 6.9 GHz is designed through equivalent circuit theory. In combination with the lossy layer, absorption above 0.8 at 3.7-5.6 GHz and 9.1-12.5 GHz was achieved. Further, the structure was fashioned into a curved surface with varying curvature, demonstrating its effective absorption and transmission properties across different curvatures. A 15 × 15 cell structure was designed and fabricated, and there was good agreement between the test results and simulation results. The proposed structure has important applications in radomes, conformal structures, and electromagnetic shielding.

5.
Glob Chang Biol ; 30(1): e17092, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38273481

RESUMEN

Mineral-associated soil organic matter (MAOM) is the largest, slowest cycling pool of carbon (C) in the terrestrial biosphere. MAOM is primarily derived from plant and microbial sources, yet the relative contributions of these two sources to MAOM remain unresolved. Resolving this issue is essential for managing and modeling soil carbon responses to environmental change. Microbial biomarkers, particularly amino sugars, are the primary method used to estimate microbial versus plant contributions to MAOM, despite systematic biases associated with these estimates. There is a clear need for independent lines of evidence to help determine the relative importance of plant versus microbial contributions to MAOM. Here, we synthesized 288 datasets of C/N ratios for MAOM, particulate organic matter (POM), and microbial biomass across the soils of forests, grasslands, and croplands. Microbial biomass is the source of microbial residues that form MAOM, whereas the POM pool is the direct precursor of plant residues that form MAOM. We then used a stoichiometric approach-based on two-pool, isotope-mixing models-to estimate the proportional contribution of plant residue (POM) versus microbial sources to the MAOM pool. Depending on the assumptions underlying our approach, microbial inputs accounted for between 34% and 47% of the MAOM pool, whereas plant residues contributed 53%-66%. Our results therefore challenge the existing hypothesis that microbial contributions are the dominant constituents of MAOM. We conclude that biogeochemical theory and models should account for multiple pathways of MAOM formation, and that multiple independent lines of evidence are required to resolve where and when plant versus microbial contributions are dominant in MAOM formation.


Asunto(s)
Minerales , Suelo , Suelo/química , Bosques , Carbono , Biomasa , Plantas , Microbiología del Suelo
6.
Inorg Chem ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918078

RESUMEN

The development of bifunctional electrocatalysts with excellent performance in both the hydrogen evolution reaction (HER) and sulfide oxidation reaction (SOR) remains a formidable challenge. Herein, we experimentally synthesize a NiO/RuO2 p-n heterojunction nanofoam that exhibits highly desirable electrocatalytic properties for both the HER and the SOR. We further design an electrolytic cell by pairing alkaline HER with SOR utilizing the NiO/RuO2 heterojunction nanofoam as both the anode and the cathode, which demands a low applied voltage of 0.846 V to achieve a current density of 10 mA cm-2. Density functional theory calculations confirm that the formation of the NiO/RuO2 p-n heterojunction nanofoam effectively regulates the electronic structure, thereby boosting the electrocatalytic performances for both HER and SOR. This work not only provides a novel strategy to prepare an efficient and stable nanofoam electrocatalyst for hydrogen production but also highlights the potential application of oxide heterojunction electrocatalysts in treating sulfur-containing waste liquid.

7.
BMC Infect Dis ; 24(1): 413, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38641791

RESUMEN

Considering that neutralizing antibody levels induced by two doses of the inactivated vaccine decreased over time and had fallen to low levels by 6 months, and homologous and heterologous booster immunization programs have been implemented in adults in China. The booster immunization of recombinant COVID-19 vaccine (ZF2001) after priming with inactivated vaccine in healthy children and adolescents has not been reported. We performed an open-labeled, single-arm clinical trial to evaluate the safety and immunogenicity of heterologous booster immunization with ZF2001 after priming with inactivated vaccine among 240 population aged 3-17 years in China. The primary outcome was immunogenicity, including geometric mean titers (GMTs), geometric mean ratios (GMRs) and seroconversion rates of SARS-CoV-2 neutralizing antibodies against prototype SARS-CoV-2 and Omicron BA.2 variant at 14 days after vaccination booster. On day 14 post-booster, a third dose booster of the ZF2001 provided a substantial increase in antibody responses in minors, and the overall occurrence rate of adverse reactions after heterologous vaccination was low and all adverse reactions were mild or moderate. The results showed that the ZF2001 heterologous booster had high immunogenicity and good safety profile in children and adolescents, and can elicit a certain level of neutralizing antibodies against Omicron.Trial registration NCT05895110 (Retrospectively registered, First posted in ClinicalTrials.gov date: 08/06/2023).


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Vacunas de Subunidad , Adolescente , Niño , Humanos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Inmunogenicidad Vacunal , SARS-CoV-2 , Vacunas de Productos Inactivados/efectos adversos , Preescolar
8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 88-97, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38433637

RESUMEN

Lumbar intervertebral disc degeneration is a common pathological process in the spine,with the main clinical symptoms of low back pain,numbness of lower limbs,and defecation dysfunction.The occurrence and development of lumbar intervertebral disc degeneration are determined by multiple factors,and the pathophysiological and cellular mechanisms remain to be fully understood.Nucleus pulposus tissue engineering is a new biotherapy that combines biological histology with material science to treat diseases including lumbar intervertebral disc degeneration.Clinicians should fully learn the complex relationship between nucleus pulposus tissue engineering and lumbar intervertebral disc degeneration,which will facilitate the clinical treatment of lumbar intervertebral disc degeneration,the rehabilitation of lumbar intervertebral disc after treatment,and the prevention of this disease in the population.


Asunto(s)
Degeneración del Disco Intervertebral , Núcleo Pulposo , Humanos , Degeneración del Disco Intervertebral/terapia , Ingeniería de Tejidos , Columna Vertebral
9.
BMC Microbiol ; 23(1): 330, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37936059

RESUMEN

BACKGROUND: Heavy metal contamination has been a severe worldwide environmental issue. For industrial pollutions, heavy metals rarely exist as singular entities. Hence, researches have increasingly focused on the detrimental effect of mixed heavy metal pollution. Genome analysis of Lampropedia strains predicted a repertoire of heavy metal resistance genes. However, we are still lack of experimental evidence regarding to heavy metal resistance of Lampropedia, and their potential in mixed heavy metal removal remain elusive. RESULTS: In this study, a Lampropedia aestuarii strain GYF-1 was isolated from soil samples near steel factory. Heavy metal tolerance assay indicated L. aestuarii GYF-1 possessed minimal inhibition values of 2 mM, 10 mM, 6 mM, 4 mM, 6 mM, 0.8 mM, and 4 mM for CdCl2, K2CrO4, CuCl2, NiCl2, Pb(CH3COO)2, ZnSO4, and FeCl2, respectively. The biosorption assay demonstrated its potential in soil remediation from mixed heavy metal pollution. Next the draft genome of L. aestuarii GYF-1 was obtained and annotated, which revealed strain GYF-1 are abundant in heavy metal resistance genes. Further evaluations on differential gene expressions suggested adaptive mechanisms including increased lipopolysaccharides level and enhanced biofilm formation. CONCLUSION: In this study, we demonstrated a newly isolated L. aestuarii GYF-1 exhibited mixed heavy metal resistance, which proven its capability of being a potential candidate strain for industrial biosorption application. Further genome analysis and differential gene expression assay suggest enhanced LPS and biofilm formation contributed to the adaptation of mixed heavy metals.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Biodegradación Ambiental , Metales Pesados/toxicidad , Metales Pesados/metabolismo , Suelo , Contaminantes del Suelo/análisis
10.
Inorg Chem ; 62(7): 3141-3152, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36757896

RESUMEN

Broadband ultraviolet (UV) excitation and red/far-red emission phosphors can effectively convert solar spectrum to enhance photosynthesis and promote morphogenesis in plants. Based on the above application requirements, Eu3+ single-doped LaAl1-yGayO3 solid solutions and Eu3+,Mn4+ codoped LaAl0.7Ga0.3O3 phosphors were designed and synthesized in this work. The LaAl0.7Ga0.3O3:0.05Eu3+ (LAG:Eu3+) phosphor exhibits a strong charge transfer band (CTB) excitation and characteristic 5D0 → 7F2 transition red emission (619 nm), which is very similar to the luminescence properties of Eu3+-organic ligand compound (EuL3). Rietveld refinement studies further revealed that the cation substitution disturbs the site symmetry. The optimal Eu3+, Mn4+ co-doped LaAl0.7Ga0.3O3 (LAG:Eu,Mn) phosphor possesses a dual-band excitation spectrum in broadband ultraviolet (UVA, UVB) area and a dual-band emission spectrum within red/far-red area. Under the sunlight radiation, the real-time spectrum of luminous laminated glasses fabricated by coating the LAG:Eu,Mn phosphor shows the percentage of radiant intensity in the red/far-red region significantly increases, suggesting that the phosphor can be a promising candidate for solar spectral conversion in plant cultivation. We believe this work provides a new idea for developing novel broadband ultraviolet excitation and red/far-red emission phosphors.

11.
Environ Sci Technol ; 57(25): 9174-9183, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37311089

RESUMEN

Plastic film mulching and urea nitrogen fertilization are widely used in agricultural ecosystems, but both their long-term use may leave a negative legacy on crop growth, due to deleterious effects of plastic and microplastic accumulation and acidification in soil, respectively. Here, we stopped covering soil with a plastic film in an experimental site that was previously covered for 33 years and compared soil properties and subsequent maize growth and yield between plots that were previously and never covered with the plastic film. Soil moisture was about 5-16% higher at the previously mulched plot than at the never-mulched plot, but NO3- content was lower for the former when with fertilization. Maize growth and yield were generally similar between previously and never-mulched plots. Maize had an earlier dough stage (6-10 days) in previously mulched compared to never-mulched plots. Although plastic film mulching did add substantial amounts of film residues and microplastic accumulation into soils, it did not leave a net negative legacy (given the positive effects of the mulching practice in the first place) for soil quality and subsequent maize growth and yield, at least as an initial effect in our experiment. Long-term urea fertilization resulted in a pH decrease of about 1 unit, which bring a temporary maize P deficiency occurring in early stages of growth. Our data add long-term information on this important form of plastic pollution in agricultural systems.


Asunto(s)
Plásticos , Suelo , Suelo/química , Zea mays , Nitrógeno/análisis , Microplásticos , Ecosistema , Agua , Agricultura , Urea , Fertilización , China
12.
Ecotoxicol Environ Saf ; 255: 114719, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-37032573

RESUMEN

The combination of glyphosate (Gly) and hard water (Hwt) is a suspected risk factor for chronic interstitial nephritis in agricultural communities (CINAC). Accumulated mitochondrial damage and proximal tubular epithelial (PTE) cell senescence have been implicated in CINAC pathogenesis. Melatonin (Mel) has potential mitochondrial function and renoprotective properties, but its role and mechanism in CINAC are unknown. Here, we detected PTE cell senescence and PTEN-induced putative protein kinase 1 (PINK1)-parkin RBR E3 ubiquitin protein ligase (Parkin)-dependent mitophagy in mice orally administered with different doses of Gly combined with Hwt (Gly: 100 mg/kg·bw and 0.7 mg/L; Hwt: 2,500 mg/L CaCO3 and 250 mg/L Ca2+) for different durations (12 and 36 w) using histological examination, transmission electron microscopy (TEM), immunofluorescence (IF) analysis, and immunohistochemistry (IHC), immunoblotting, ELISA and biochemical assays with kits. The same assays were performed after combination treatment with Mdivi-1 (an inhibitor of mitophagy, i.p. 10 mg/kg·bw, twice a week for 12 w) or Mel (i.p. 10 mg/kg·bw, once a day for 12 w) under high-level exposure. Gly combined with Hwt (Gly-Hwt) significantly increased P16-P21-dependent PTE cell senescence, mitochondrial fission and oxidative stress, and activated PINK1-Parkin-mediated mitophagy, accompanied by defective autophagic flux at high doses but unaltered autophagic flux at low doses. Improved senescence occurred after Mdivi-1 administration, suggesting that mitophagy is involved in cellular senescence. Mel significantly decreased senescence induced by Gly-Hwt. Furthermore, PINK1-Parkin-dependent mitophagy and autophagic flux were markedly enhanced, and mitochondrial function was improved, as evidenced by reductions in mitochondrial fission and subsequent oxidative damage. Thus, Gly and Hwt synergistically promote PTE cell senescence through PINK1-Parkin-mediated mitophagy, and Mel exerts renoprotective effects by modulating mitophagy, suggesting therapeutic applications in ageing-related CINAC.


Asunto(s)
Melatonina , Mitofagia , Ratones , Animales , Proteínas Quinasas/metabolismo , Melatonina/farmacología , Especies Reactivas de Oxígeno/metabolismo , Senescencia Celular , Ubiquitina-Proteína Ligasas/metabolismo , Glifosato
13.
Int J Environ Health Res ; : 1-15, 2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38153391

RESUMEN

Existing evidence suggested that the risk of tuberculosis (TB) infection was associated to the variations in temperature and PM2.5. A total of 9,111 cases of TB were reported in Ningxia Hui Autonomous Region, China from 2013 to 2015 on a daily basis, and 57.2% of them were male. The TB risk was more prominent for a lower temperature in males (RR of 1.724, 95% CI: 1.241, 2.394), the aged over 64 years (RR of 2.241, 95% CI: 1.554, 3.231), and the high mobility occupation subpopulation (RR of 2.758, 95% CI: 1.745, 4.359). High concentration of PM2.5 showed a short-term effect and was only associated with an increased risk in the early stages of exposure for the female, and aged 36-64 years group. There were 15.06% (1370 cases) of cases of TB may be attributable to the temperature, and 2.94% (268 cases) may be attributable to the increase of PM2.5 exposures. Low temperatures may be associated with significantly increase in the risk of TB, and high PM2.5 concentrations have a short-term association on increasing the risk of TB. Strengthening the monitoring and regular prevention and control of high risk groups will provide scientific guidance to reduce the incidence of TB.

14.
Small ; 18(26): e2201803, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35616079

RESUMEN

As a promising 2D nanocarrier, the biggest challenge of bare black phosphorus nanosheets (BP NSs) lies in the inherent instability, while it can be improved by surface modification strategies to a great extent. Considering the existing infirm BP NSs surface modification strategies, A mussels-inspired strong adhesive biomimetic peptide with azide groups for surface modification to increase the stability of BP NSs is synthesized. The azide groups on the peptide can quickly and precisely bind to the targeting ligand through click chemistry, solving the problem of nonspecificity of secondary modification of other mussel-mimicking materials. Besides, a catechol-Gd3+ coordination network is further constructed for magnetic resonance imaging (MRI) and inducing intracellular endo/lysosome escape. The fabricated BP-DOX@Gd/(DOPA)4 -PEG-TL nanoplatform exhibits enhanced antitumor abilities through synergetic chemo/photothermal effects both in vitro and in vivo.


Asunto(s)
Nanopartículas , Neoplasias , Azidas , Doxorrubicina/farmacología , Humanos , Ligandos , Imagen Multimodal , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Fósforo , Fototerapia/métodos
15.
BMC Med Res Methodol ; 22(1): 151, 2022 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-35614385

RESUMEN

OBJECTIVE: Middle-aged and older adults are more likely to suffer from chronic diseases because of their particular health characteristics, which lead to a high incidence of catastrophic health expenditure (CHE). This study plans to analyse the different factors affecting CHE in middle-aged and older adults with chronic diseases, target the vulnerable characteristics, and suggest groups that medical insurance policies should pay more attention to. METHODS: The data used in this study came from the 2018 China Health and Retirement Longitudinal Study (CHARLS) database. The method of calculating the CHE was adopted from the World Health Organization (WHO). The logistic regression was used to determine the family characteristics of chronic disease in middle-aged and older adults with a high probability of incurring CHE. RESULTS: The incidence of CHE in middle-aged and older adults with chronic disease was highest in sub-poverty level families (26.20%) was lowest in wealthier level families (20.07%). Households with malignant tumours had the highest CHE incidence under any circumstances, especially if the householder had been using inpatient service in the past year. Among the comparison of CHE incidence in different types of medical insurance, the Urban and Rural Residents' Basic Medical Insurance (URRBMI) was the highest (27.46%). The incidence of CHE was 2.73 times (95% CI 2.30-3.24) and 2.16 times (95% CI 1.81-2.57) higher among people who had used inpatient services in the past year or outpatient services in the past month than those who had not used them. CONCLUSIONS: Relatively wealthy economic conditions cannot significantly reduce the financial burden of chronic diseases in middle-aged and older adults. For this particular group with multiple vulnerabilities, such as physical and social vulnerability, the high demand and utilization of health services are the main reasons for the high incidence of CHE. After achieving the goal of lowering the threshold of universal access to health services, the medical insurance system in the next stage should focus on multiple vulnerable groups and strengthen the financial protection for middle-aged and older adults with chronic diseases, especially for patients with malignant tumours.


Asunto(s)
Gastos en Salud , Neoplasias , Anciano , Atención Ambulatoria , China/epidemiología , Enfermedad Crónica , Humanos , Seguro de Salud , Estudios Longitudinales , Persona de Mediana Edad
16.
Inorg Chem ; 61(8): 3631-3640, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35176862

RESUMEN

The tetravalent-state stability of manganese is of primary importance for Mn4+ luminescence. Double perovskite-structured A2B'B″O6:Mn4+ has been recently prevalent, and the manganese ions are assumed to substitute for the B″(IV-VI)O6 site to stabilize at the tetravalent charge state to generate far-red emissions. However, some Mn-doped A2B'B″O6-type materials show no or weak luminescence such as typical Ca2MgWO6:Mn. In this work, a cation-pair co-substitution strategy is proposed to replace 2Ca2+ by Na+-La3+ to form Ca2-2xNaxLaxMgWO6:Mn. The significant structural distortion appears in the solid solution lattices with the contraction of [MgO6] but enlargement of [WO6] octahedron. We hypothesize that the site occupancy preference of Mn migrates from Mg2+ to W6+ sites. As a result, the effective Mn4+/Mn2+ concentration enhances remarkably to regulate nonluminescence to highly efficient Mn4+-related far-red emission. The optimal CaNa0.5La0.5MgWO6:0.9%Mn4+ shows an internal quantum efficiency of 94% and external quantum efficiency of 82%, reaching up to the top values in Mn4+-doped oxide phosphors. This work may provide a new perspective for the rational design of Mn4+-activated red phosphors, primarily considering the site occupancy modification and tetravalent-state stability of Mn.

17.
Environ Res ; 205: 112547, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34902378

RESUMEN

The aerobic granular sludge (AGS) process is a promising technology for wastewater treatment. However, a long start-up period for granulation and instability during long-term operation still hinder the application of AGS technology, especially for low-strength wastewater. To solve these two problems, this study tested a novel strategy involving the selection of slow-growing organisms and the addition of carriers in an anaerobic-aerobic-anoxic sequencing batch reactor (AN/O/AX_SBR). Three identical AN/O/AX_SBRs (R_Ctrl, R_CCM, and R_GAC), fed with low-strength wastewater, were operated for 120 days. R_Ctrl had no carriers, R_CCM contained cell culture microcarriers (CCM), and R_GAC contained granular activated carbon (GAC). Mature AGS was achieved within 80 days in all reactors. The carriers could reduce the maturation period of AGS by approximately 10 days (76, 66, and 69 days in R_Ctrl, R_CCM, and R_GAC, respectively) and improve the physical strength of the AGS. AGS showed a strong structure without excessive proliferation of filamentous bacteria, full-grown size (900-1100 µm), and good settleability (SVI5 was 15.4-19.4 mL/g). Microbiological analysis showed that AN/O/AX_SBRs can provide a metabolic selective pressure to select slow-growing organisms such as nitrifying bacteria (norank_f__NS9_marine_group, Ellin6067, and Nitrospira), glycogen and phosphorus accumulating organisms (GAOs: Candidatus_Competibacter and Defluviicoccus; PAOs: Candidatus_Accumulibacter and Flavobacterium). All reactors showed good performance for simultaneous nitrification, endogenous denitrification, and phosphorus removal. The removal efficiencies of total nitrogen and total phosphorous were above 70% and 80%, respectively. The cycle test showed intermediate PAO-GAO metabolism prevailed in the system, and endogenous denitrification was primarily carried out by denitrifying GAOs.


Asunto(s)
Eliminación de Residuos Líquidos , Aguas Residuales , Anaerobiosis , Reactores Biológicos/microbiología , Nitrógeno/análisis , Fósforo/metabolismo , Aguas del Alcantarillado/microbiología , Aguas Residuales/química
18.
Environ Res ; 212(Pt D): 113464, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35623442

RESUMEN

The rapid start-up and advanced nutrient removal of simultaneous nitrification, endogenous denitrification, and phosphorus (P) removal aerobic granular sequence batch reactor (SNEDPR-AGSBR) is a challenge in the treatment of low carbon/nitrogen (C/N) domestic sewage. In this study, the feasibility of the SNEDPR-AGSBR process was examined in an exceedingly single-stage anaerobic/aerobic/anoxic sequencing batch reactor for treating low C/N ratio (3.3-5.0) domestic sewage. The initial results showed that accompanied by the rapid formation of the mature aerobic granular sludge based on the selection for slow-growing organisms, the rapid start-up (38 d) of the SNEDPR-AGSBR process was successfully realized. The formed mature aerobic granules had a dense structure with an average diameter of 667.7 µm and SVI30 of 30.0 mL/g. Two conditions for achieving the competitive balance between phosphorus-accumulating organisms/denitrifying phosphorus-accumulating organisms (PAOs/DPAOs) and glycogen accumulating organisms/denitrifying glycogen accumulating organisms (GAOs/DGAOs) were revealed by the long-term operation results. First, the dissolved oxygen (DO) concentration needed to be decreased to 3.0 mg/L in the aerobic phase, and then, the aerobic and anoxic phase hydraulic retention time (HRT) should be increased to 3.0 h. Notably, high removal efficiencies for NH4+-N (100%), total nitrogen (84.3%), and P (91.8%) of the SNEDPR-AGSBR process were stably obtained with a low C/N ratio of 3.9 domestic sewage. Simultaneous nitrification and endogenous denitrification (SNED) efficiency of 61.6% was achieved during a long-term operation of 142 days. Finally, microbial community analysis confirmed that GAOs (Defluviicoccus)/DGAOs (Candidatus_Competibacter) were responsible for the removal N, and PAOs (Acinetobacter, Candidatus_Accumulibacter, Hypomicrobinm)/DPAOs (Pseudomonas and Dechloromonas) ensured P removal.


Asunto(s)
Nitrificación , Fósforo , Reactores Biológicos , Carbono , Desnitrificación , Glucógeno , Nitrógeno , Nutrientes , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/métodos , Aguas Residuales
19.
Ecotoxicol Environ Saf ; 241: 113803, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36068739

RESUMEN

Chronic interstitial nephritis in agricultural communities (CINAC) is a severe and widespread disease that has been associated with environmental and occupational exposure to glyphosate and hard water. However, the potential underlying mechanisms remain incompletely understood. Melatonin is reported to exert protective effects on the kidney, but whether melatonin can attenuate renal tubular injury in mice exposed to glyphosate combined with hard water is unclear. Here, mice were treated with high doses and environmentally relevant doses of glyphosate (100 mg/kg·bw and 0.7 mg/L, respectively) and/or hard water (2500 mg/L CaCO3 and 250 mg/L Ca2+, respectively) via their drinking water for 12 weeks. We found that high-dose glyphosate or hard water treatment significantly increased the levels of biomarkers of renal damage, including ß2-microglobulin, neutrophil gelatinase-associated lipid carrier protein, and/or albumin, in the urine; these increased biomarker levels were correlated with obvious morphological changes, and all of these changes were also observed in animals exposed to environmentally relevant doses of glyphosate and/or high Ca2+ water. Melatonin (10 mg/kg·bw, intraperitoneal injection, daily for 12 weeks) administered concomitantly with high doses of glyphosate and hard water inhibited the glyphosate- and hard water-induced increases in the levels of kidney injury biomarkers and changes in morphology; this result was intriguing. Additionally, glyphosate combined with hard water at both high and environmentally relevant doses significantly upregulated the expression of the endoplasmic reticulum (ER) stress marker proteins Bip, ATF6, and PERK as well as the pyroptosis-related proteins (NLRP3 and caspase 1 signaling proteins) in renal tissues. Similarly, melatonin significantly attenuated the increased ER stress and pyroptosis induced by high doses of glyphosate and hard water. In summary, we conclude that exposure to glyphosate and hard water at both high doses and environmentally relevant doses causes renal dysfunction in mice, and this dysfunction can be attenuated by melatonin, possibly through the inhibition of ER stress and pyroptosis. Our results support the notion that melatonin may have therapeutic potential for the treatment of chronic kidney diseases.


Asunto(s)
Melatonina , Insuficiencia Renal Crónica , Animales , Estrés del Retículo Endoplásmico , Glicina/análogos & derivados , Glicina/toxicidad , Melatonina/farmacología , Ratones , Glifosato
20.
Ecotoxicol Environ Saf ; 245: 114098, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36137422

RESUMEN

Cadmium (Cd), the common environmental pollutant, primarily targets at renal proximal tubules and induces nephrotoxicity. Cellular senescence, a phenomenon of cell growth arrest and a characteristics of maladaptive cell self-repair, is associated with renal disease progression. However, whether and how Cd induces renal tubular cells premature senescence is unknown. In our study, we found that Cd induced kidney damage and dysfunctions, which correlated with exacerbated tubular cell senescence, evidenced by increased senescence-associated ß-galactosidase activity, the upregulated protein expression of p53 and p21Waf1/Cip1 proteins, and elevated expression and secretion of cytokines in human proximal tubular epithelial HK-2 cells in vitro and in Cd-treated mice in vivo. Moreover, a S-phase arrest and decrease in Edu positive rate were found in Cd-treated HK-2 cells. Mechanistically, Cd suppressed the expression and activity of Sirtuin-1 (SIRT1), an anti-senescence deacetylase, resulting in the accumulation of acetylated p53 and upregulation of p21Waf1/Cip1. Activation of SIRT1 significantly abolished Cd-induced premature senescence and S-phase arrest. Finally, silencing p21Waf1/Cip1 efficiently delayed premature senescence and recovered cell cycle progression. These findings indicate that Cd promotes tubular cells senescence and impairs tubular cells regeneration, resulting in kidney dysfunctions, which could be ameliorated by SIRT1 activation.


Asunto(s)
Contaminantes Ambientales , Sirtuina 1 , Animales , Cadmio/metabolismo , Cadmio/toxicidad , Senescencia Celular , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Citocinas/metabolismo , Contaminantes Ambientales/metabolismo , Humanos , Riñón/metabolismo , Ratones , Sirtuina 1/genética , Sirtuina 1/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , beta-Galactosidasa
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