Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 46
Filtrar
1.
Angew Chem Int Ed Engl ; : e202407240, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38839564

RESUMEN

One-step purification of ethylene from ternary mixtures (C2H2, C2H4, and C2H6) can greatly reduce the energy consumption of the separation process, but it is extremely challenging. Herein, we use crystal engineering and reticular chemistry to introduce unsaturated bonds (ethynyl and alkyne) into ligands, and successfully design and synthesized two novel Zr-MOCs (ZrT-1-ethenyl and ZrT-1-alkyne). The introduction of carbon-carbon unsaturated bonds provides abundant adsorption sites within the framework while modulating the pore window size. Comprehensive characterization techniques including single crystal and powder X-ray diffraction, as well as electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) confirm that ZrT-1-ethenyl and ZrT-1-alkyne possess an isostructural framework with ZrT-1 and ZrT-1-Me, respectively. Adsorption isotherms and breakthrough experiments combined with theoretical calculations demonstrate that ZrT-1-ethenyl can effectively remove trace C2H2 and C2H6 in C2H4 and achieve separation of C2H2 from C2H4 and CO2. ZrT-1-ethenyl can also directly purify C2H4 in liquid solutions. This work provides a benchmark for MOCs that one-step purification of ethylene from ternary mixtures.

2.
J Exp Bot ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38628155

RESUMEN

Optimal stomatal regulation is important for plant adaptation to changing environmental conditions and for maintaining crop yield. The guard-cell signal GABA is produced from glutamate by Glutamate Decarboxylase (GAD) during a reaction that generates carbon dioxide (CO2) as a by-product. Here, we investigated a putative connection between GABA signalling and the more clearly defined CO2 signalling pathway in guard cells. The GABA-deficient mutant lines gad2-1, gad2-2 and gad1/2/4/5 were examined for stomatal sensitivity to various CO2 concentrations. Our findings show a phenotypical discrepancy between the allelic mutant lines gad2-1 and gad2-2 - a weakened CO2 response in gad2-1 (GABI_474_E05) in contrast to a wild-type response in gad2-2 (SALK_028819) and gad1/2/4/5. Through transcriptomic and genomic investigation, we traced the response of gad2-1 to a deletion of full-length Mitogen-activated protein kinase 12 (MPK12) in the GABI-KAT line, thereafter as renamed gad2-1*. Guard cell-specific complementation of MPK12 restored the gad2-1* CO2 phenotype, which confirms the proposed importance of MPK12 to CO2 sensitivity. Additionally, we found that stomatal opening under low atmospheric CO2 occurs independently of the GABA-modulated opening-channel ALMT9. Our results confirm that GABA has a role in modulating the rate of stomatal opening and closing - but not in response to CO2  per se.

3.
Food Sci Nutr ; 12(2): 765-775, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38370083

RESUMEN

Formulas containing intact cow milk protein are appropriate alternatives when human milk (HM) is not feasible. However, for babies with a physician-diagnosed cow milk protein allergy (CMPA), hydrolyzed formulas are needed. We conducted a 3-month, open-label, nonrandomized concurrent controlled trial (ChiCTR2100046909) between June 2021 and October 2022 in Qingdao City, China. In this study, CMPA toddlers were fed with a partially hydrolyzed formula containing synbiotics (pHF, n = 43) and compared with healthy toddlers fed a regular intact protein formula (IF, n = 45) or HM (n = 21). The primary endpoint was weight gain; the secondary endpoints were changes in body length and head circumference of both CMPA and healthy toddlers after 3-month feeding; and the exploratory outcomes were changes in gut microbiota composition. After 3 months, there were no significant group differences for length-for-age, weight-for-age, or head circumference-for-age Z scores. In the gut microbiota, pHF feeding increased its richness and diversity, similar to those of IF-fed and HM-fed healthy toddlers. Compared with healthy toddlers, the toddlers with CMPA showed an increased abundance of phylum Bacteroidota, Firmicutes, class Clostridia, and Bacteroidia, and a decreased abundance of class Negativicutes, while pHF feeding partly eliminated these original differences. Moreover, pHF feeding increased the abundance of short-chain fatty acid producers. Our data suggested that this pHF partly simulated the beneficial effects of HM and shifted the gut microbiota of toddlers with CMPA toward that of healthy individuals. In conclusion, this synbiotic-containing pHF might be an appropriate alternative for toddlers with CMPA.

5.
ACS Appl Mater Interfaces ; 16(6): 7819-7825, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38300743

RESUMEN

Adsorptive separation technology provides an effective approach for separating gases with similar physicochemical properties, such as the purification of acetylene (C2H2) from carbon dioxide (CO2). The high designability and tunability of metal-organic framework (MOF) adsorbents make them ideal design platforms for this challenging separation. Herein, we employ an isoreticular functionalization strategy to fine-tune the pore environment of Zr- and Th-based UiO-66 by the immobilization of the benzothiadiazole group via bottom-up synthesis. The functionalized UPC-120 exhibits an enhanced C2H2/CO2 separation performance, which is confirmed by adsorption isotherms, dynamic breakthrough curves, and theoretical simulations. The synergy of ligand functionalization and metal ion fine-tuning guided by isoreticular chemistry provides a new perspective for the design and development of adsorbents for challenging gas separation processes.

7.
Nutr Metab Cardiovasc Dis ; 34(5): 1146-1156, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38220508

RESUMEN

BACKGROUND AND AIMS: Carotid atherosclerosis is associated with an elevated risk of stroke in patients with chronic kidney disease. However, the molecular basis for the incidence of carotid atherosclerosis in patients with CKD is poorly understood. Here, we investigated whether circulating miR-423-5p is a crucial link between CKD and carotid atherosclerosis. METHODS AND RESULTS: We recruited 375 participants for a cross-sectional study to examine the occurrence of carotid plaque and plaque thicknesses. Levels of miR-423-5p were determined by qPCR analysis. We found that non-dialysis CKD patients had higher circulating exosomal and plasma miR-423-5p levels, and dialysis-dependent patients had lower miR-423-5p levels than non-dialysis CKD patients. After excluding for the influence of dialysis patients, linear regression analysis indicated that levels of circulating miR-423-5p are negatively correlated with eGFR (P < 0.001). Higher plasma miR-423-5p levels were associated with the incidence and severity of carotid plaques. In parallel, we constructed a murine model of CKD with a 5/6 nephrectomy protocol and performed RNA sequencing studies of aortic tissues. Consistent with these findings in CKD patients, circulating exosomal miR-423-5p levels in CKD mice were elevated. Furthermore, our RNA-seq studies indicated that the putative target genes of miR-423-5p were related to oxidative stress functions for aorta of CKD mice. CONCLUSION: Levels of miR-423-5p are associated with the presence and severity of carotid plaque in CKD. Data from our mouse model suggests that miR-423-5p likely influences gene expression programs related to oxidative stress in aorta of CKD mice.


Asunto(s)
Enfermedades de las Arterias Carótidas , MicroARNs , Placa Aterosclerótica , Insuficiencia Renal Crónica , Humanos , Animales , Ratones , Estudios Transversales , Enfermedades de las Arterias Carótidas/epidemiología , Enfermedades de las Arterias Carótidas/genética , Enfermedades de las Arterias Carótidas/complicaciones , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/genética , MicroARNs/metabolismo
8.
New Phytol ; 241(1): 73-81, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37936524

RESUMEN

γ-Aminobutyric acid (GABA) accumulates rapidly under stress via the GABA shunt pathway, which has been implicated in reducing the accumulation of stress-induced reactive oxygen species (ROS) in plants. γ-Aminobutyric acid has been demonstrated to act as a guard-cell signal in Arabidopsis thaliana, modulating stomatal opening. Knockout of the major GABA synthesis enzyme Glutamate Decarboxylase 2 (GAD2) increases the aperture of gad2 mutants, which results in greater stomatal conductance and reduces water-use efficiency compared with wild-type plants. Here, we found that the additional loss of GAD1, GAD4, and GAD5 in gad2 leaves increased GABA deficiency but abolished the more open stomatal pore phenotype of gad2, which we link to increased cytosolic calcium (Ca2+ ) and ROS accumulation in gad1/2/4/5 guard cells. Compared with wild-type and gad2 plants, glutamate was ineffective in closing gad1/2/4/5 stomatal pores, whereas lowering apoplastic calcium, applying ROS inhibitors or complementation with GAD2 reduced gad1/2/4/5 guard-cell ROS, restored the gad2-like greater stomatal apertures of gad1/2/4/5 beyond that of wild-type. We conclude that GADs are important contributors to ROS homeostasis in guard cells likely via a Ca2+ -mediated pathway. As such, this study reveals greater complexity in GABA's role as a guard-cell signal and the interactions it has with other established signals.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Calcio/metabolismo , Estomas de Plantas , Ácido gamma-Aminobutírico/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Homeostasis , Ácido Abscísico/metabolismo
9.
Nutr Metab Cardiovasc Dis ; 33(10): 1960-1968, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37544869

RESUMEN

BACKGROUND AND AIMS: This study was performed to investigate the effect of coffee consumption on abdominal aortic calcification (AAC) among adults with and without hypertension, diabetes, and cardiovascular diseases (CVD). METHODS AND RESULTS: A total of 2548 participants from the National Health and Nutrition Examination Survey (NHANES) 2013-2014 were included. Coffee consumption was obtained from 24-h dietary recalls. Dual-energy X-ray absorptiometry (DXA) was used to measure the severity of AAC. In the fully adjusted model, compared with non-drinkers, high coffee consumption (≥390 g/d) was associated with higher AAC scores among participants with hypertension (ß = 0.72, 95% CI: 0.21-1.22), diabetes (ß = 1.20, 95% CI: 0.35-2.05), and CVD (ß = 2.03, 95% CI: 0.71-3.36). We did not observe such an association among participants without hypertension, diabetes, and CVD. Furthermore, decaffeinated coffee was not associated with AAC. CONCLUSION: In conclusion, patients with hypertension, diabetes, and CVD should focus on coffee consumption, especially caffeinated coffee, to reduce the burden of AAC.


Asunto(s)
Enfermedades de la Aorta , Enfermedades Cardiovasculares , Diabetes Mellitus , Hipertensión , Calcificación Vascular , Humanos , Adulto , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Encuestas Nutricionales , Hipertensión/diagnóstico , Hipertensión/epidemiología , Hipertensión/complicaciones , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , Dieta , Aorta Abdominal/diagnóstico por imagen , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/epidemiología , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/epidemiología , Factores de Riesgo
10.
Sci Total Environ ; 903: 166234, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-37572899

RESUMEN

Selenium (Se) has been reported to have an antagonistic effect on heavy metals in animals. However, there is no epidemiological study investigating whether Se could protect against the pulmonary toxicity of Cadmium (Cd) and Lead (Pb). Data was collected from the 2011-2012 National Health and Nutrition Examination Survey (NHANES) cycle. Pulmonary function was assessed by Forced Vital Capacity (FVC), Forced Expiratory Volume 1st Second (FEV1) and FEV1/FVC. Blood concentrations of Cd, Pb, and Se were measured using inductively coupled plasma mass spectrometry. Linear regression, restricted cubic splines, and quantile-based g-computation (qgcomp) were performed to evaluate the individual and joint associations of Cd and Pb with pulmonary function and whether Se modified these associations. In the adjusted multi-metal model, every 1-unit increase in Cd, FEV1, FVC, and FEV1/FVC decreased by 76.437 mL (95 % CI: -110.928 to -41.947), 42.719 mL (95 % CI: -84.553 to -0.885), and 0.012 (95 % CI: -0.016 to -0.007), respectively. Meanwhile, FEV1 decreased by 9.37 mL (95 % CI: -18.61 to -0.13) for every 1 unit increase in Pb. Furthermore, we found an inverted U-shape association between Se and lung function, and participants in the second quartile Se group had the highest increases in FEV1 and FVC compared with participants in the lowest quartile. Qgcomp model also revealed that the toxic metal mixture (Cd and Pb) exhibited a significant inverse association with FEV1 and FEV1/FVC. Furthermore, we found that the inverse association of Pb and Cd, either alone or in combination, with pulmonary function first diminished with increasing Se levels but was re-enforced when blood Se concentrations were in the highest quartile. Our results indicated that moderate Se attenuated the harmful effects of Cd and Pb on lung function.

11.
J Hazard Mater ; 459: 132142, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37515992

RESUMEN

Microplastics (MPs) occur and distribute widely in agroecosystems, posing a potential threat to soil-plant systems. However, little is known about their effects on legumes and N-fixing microbes. Here, we explored the effects of high-density polyethylene (HDPE), polystyrene (PS), and polylactic acid (PLA) on the growth of peanuts and soil N-fixing bacterial communities. All MPs treatments showed no phytotoxic effects on plant biomass, and PS and PLA even increased plant height, especially at the high dose. All MPs changed soil NO3--N and NH4+-N contents and the activities of urease and FDAse. Particularly, high-dose PLA decreased soil NO3--N content by 97% and increased soil urease activity by 104%. In most cases, MPs negatively affected plant N content, and high-dose PLA had the most pronounced effects. All MPs especially PLA changed soil N-fixing bacterial community structure. Symbiotic N-fixer Rhizoboales were greatly enriched by high-dose PLA, accompanied by the emergence of root nodulation, which may represent an adaptive strategy for peanuts to overcome N deficiency caused by PLA MPs pollution. Our findings indicate that MPs can change peanut-N fixing bacteria systems in a type- and dose-dependent manner, and biodegradable MPs may have more profound consequences for N biogeochemical cycling than traditional MPs.


Asunto(s)
Arachis , Fabaceae , Microplásticos/toxicidad , Plásticos , Fijación del Nitrógeno , Ureasa , Bacterias , Poliésteres , Poliestirenos , Suelo
12.
Sleep Med ; 108: 22-28, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37307697

RESUMEN

BACKGROUND: Currently, it's unclear whether sleep-disordered breathing (SDB) and reduced lung function could synergistically increase the incidence of coronary heart disease (CHD). Furthermore, the predictive value of different lung function indices for the incidence of CHD remains unknown. METHODS: We enrolled 3749 participants from the Sleep Heart Health Study (SHHS) to conduct a retrospective study. The individuals were divided into the SDB and non-SDB subgroups according to Apnoea-Hypopnoea Index (AHI). Cox regression models were used to evaluate the association between lung function and CHD. We also conducted a ROC analysis to assess the predictive value of different lung function indices. RESULTS: 512 cases of CHD were identified during an average of 10.40 years of follow-up in participants without CVD at baseline. We observed that lung function was a better predictor of CHD in non-SDB participants compared with SDB participants. Reduced lung function was associated with a higher risk of CHD in participants without SDB, while the inverse association became non-significant in participants with SDB. Furthermore, the incremental contribution of lung function to CHD diminished with increasing severity of SDB. CONCLUSION: We need to focus more on the lung function of individuals without SDB rather than those with SDB to reduce the risk of CHD.


Asunto(s)
Enfermedad Coronaria , Síndromes de la Apnea del Sueño , Humanos , Incidencia , Estudios Retrospectivos , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/epidemiología , Enfermedad Coronaria/epidemiología , Pulmón
13.
J Funct Biomater ; 14(6)2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37367282

RESUMEN

This prospective study aimed to evaluate the effectiveness of decellularized porcine conjunctiva (DPC) in the management of severe symblepharon. Sixteen patients with severe symblepharon were enrolled in this study. After symblepharon lysis and Mitomycin C (MMC) application, tarsus defects were covered with residual autologous conjunctiva (AC), autologous oral mucosa (AOM), or DPC throughout the fornix, and DPC was used for all the exposed sclera. The outcomes were classified as complete success, partial success, or failure. Six symblepharon patients had chemical burns and ten had thermal burns. Tarsus defects were covered with DPC, AC, and AOM in two, three, and eleven cases, respectively. After an average follow-up of 20.0 ± 6 months, the anatomical outcomes observed were complete successes in twelve (three with AC+DPC, four with AC+AOM+DPC, and five with AOM+DPC) (75%) cases, partial successes in three (one with AOM+DPC and two with DPC+DPC) (18.75%) cases, and failure in one (with AOM+DPC) (6.25%) case. Before surgery, the depth of the narrowest part of the conjunctival sac was 0.59 ± 0.76 mm (range, 0-2 mm), tear fluid quantity (Schirmer II tests) was 12.5 ± 2.26 mm (range, 10-16 mm), and the distance of the eye rotation toward the opposite direction of the symblepharon was 3.75 ± 1.39 mm (range, 2-7 mm). The fornix depths increased to 7.53 ± 1.64 mm (range, 3-9 mm), eye movement was significantly improved, and the distance of eye movement reaching 6.56 ± 1.24 mm (range, 4-8 mm) 1 month after the operation; the postoperative Schirmer II test (12.06 ± 2.90 mm, range, 6-17 mm) was similar to that before surgery. Goblet cells were finally found in fifteen patients by conjunctival impression cytology in the transplantation area of DPC, except for one patient who failed. DPC could be considered an alternative for ocular surface reconstruction of severe symblepharon. Covering tarsal defects with autologous mucosa is necessary for extensive reconstruction of the ocular surface.

14.
New Phytol ; 238(2): 904-915, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36683442

RESUMEN

Using microscopy to investigate stomatal behaviour is common in plant physiology research. Manual inspection and measurement of stomatal pore features is low throughput, relies upon expert knowledge to record stomatal features accurately, requires significant researcher time and investment, and can represent a significant bottleneck to research pipelines. To alleviate this, we introduce StomaAI (SAI): a reliable, user-friendly and adaptable tool for stomatal pore and density measurements via the application of deep computer vision, which has been initially calibrated and deployed for the model plant Arabidopsis (dicot) and the crop plant barley (monocot grass). SAI is capable of producing measurements consistent with human experts and successfully reproduced conclusions of published datasets. SAI boosts the number of images that can be evaluated in a fraction of the time, so can obtain a more accurate representation of stomatal traits than is routine through manual measurement. An online demonstration of SAI is hosted at https://sai.aiml.team, and the full local application is publicly available for free on GitHub through https://github.com/xdynames/sai-app.


Asunto(s)
Arabidopsis , Humanos , Fenotipo , Computadores , Estomas de Plantas/fisiología
15.
Food Sci Technol Int ; 29(3): 195-203, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35075940

RESUMEN

To investigate the composition, physicochemical, functional, and structural properties of citrus insoluble dietary fiber concentrate from citrus peel affected by different particle sizes, citrus insoluble dietary fiber concentrate was modified by coarse crush and superfine grinding treatments. The results showed that the contents of hemicellulose and lignin significantly decrease and a significant increase in cellulose and insoluble dietary fiber contents with the reduction in particle size. In addition, the markedly decreased particle size and obviously microstructural changes of citrus insoluble dietary fiber concentrate powder were observed. The color value of citrus insoluble dietary fiber concentrate was observably improved, crystallinity and thermal stability of modified fiber slightly increase with the decrease in particle size, which is due to the partial elimination of hemicellulose and lignin after the treatments. However, water holding capacity, water swelling capacity, and oil holding capacity were found to be lower with the reduction in particle size, which might be attributed to the fact that superfine grinding treatment destroyed the structure integrity, thus causing some soluble components to break away from the cellulose backbone, or due to aggregation of smaller granules. The present study suggested that decreasing the particle size could effectively change some properties of citrus insoluble dietary fiber concentrate, which will provide new perspectives for the application of citrus insoluble dietary fiber concentrate in food products.


Asunto(s)
Citrus , Citrus/química , Tamaño de la Partícula , Fibras de la Dieta , Lignina , Celulosa , Agua/química
16.
Nutrients ; 14(24)2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36558503

RESUMEN

Life's Simple 7 (LS7) is the American Heart Association's (AHA) proposal for a healthy lifestyle, also known as cardiovascular health (CVH) metrics. However, the association between CVH metrics and the severity of hepatic steatosis and liver fibrosis detected by transient elastography is unknown. We performed a cross-sectional study using the data from the 2017-2018 National Health and Nutrition Examination Survey (NHANES) cycle. The controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) were used to evaluate the severity of hepatic steatosis and liver fibrosis and to define NAFLD, advanced liver fibrosis, and cirrhosis. A total of 2679 participants were included. Multivariate linear regression analysis revealed that per 1-unit increase in the CVH metric, CAP and LSM decreased by 8.565 units and 0.274 units, respectively. In the multivariate logistic regression analysis, the risk of NAFLD, advanced liver fibrosis, and cirrhosis were 7, 10, and 6 times higher in the poor CVH group than in the ideal CVH group. Subgroup analysis indicated that CVD patients and non-Hispanic whites could benefit more from ideal CVH. In conclusion, adherence to ideal CVH metrics, as proposed by the AHA, can significantly reduce the risk of hepatic steatosis and liver fibrosis.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Enfermedad del Hígado Graso no Alcohólico , Humanos , Estados Unidos/epidemiología , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Factores de Riesgo , Encuestas Nutricionales , Estudios Transversales , Indicadores de Calidad de la Atención de Salud , Cirrosis Hepática/diagnóstico por imagen
17.
Nutrients ; 14(17)2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-36079748

RESUMEN

Peripheral arterial disease (PAD) has a strong relationship with inflammation. However, it is unclear whether the dietary inflammatory potential is associated with PAD. We aimed to address this knowledge gap. The dietary inflammatory index (DII) was obtained using a 24-h dietary recall interview for each individual. Logistic regression models and restricted cubic spline were performed to assess the relationship of DII with the prevalence of PAD. In addition, Spearman correlation analysis and subgroup analysis were also undertaken. In total, 5840 individuals from the 1999-2004 National Health and Nutrition Examination Survey (NHANES) were enrolled in our study. Participants in higher DII quartile tended to have higher rates of PAD. The increase in DII scores showed a positive association with PAD after fully multivariate adjustment (OR (odds ratios) = 1.094, 95% confidence interval (CI): 1.022-1.171). The multivariable-adjusted OR and 95% CI of the highest DII index quartile compared with the lowest quartile was 1.543 (95% CI: 1.116-2.133). Subgroup analysis demonstrated that the positive association between DII and PAD was persistent across population subgroups. In conclusion, we report that a proinflammatory dietary pattern is related to a higher risk of developing PAD among US adults.


Asunto(s)
Dieta , Enfermedad Arterial Periférica , Adulto , Estudios Transversales , Dieta/efectos adversos , Humanos , Inflamación/epidemiología , Encuestas Nutricionales , Enfermedad Arterial Periférica/epidemiología , Enfermedad Arterial Periférica/etiología , Factores de Riesgo
18.
mBio ; 13(3): e0372121, 2022 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-35491828

RESUMEN

The rhizobium-legume symbiosis is essential for sustainable agriculture by reducing nitrogen fertilizer input, but its efficiency varies under fluctuating soil conditions and resources. The nitrogen-related phosphotransferase system (PTSNtr) consisting of PtsP, PtsO, and PtsN is required for optimal nodulation and nitrogen fixation efficiency of the broad-host-range Sinorhizobium fredii CCBAU45436 associated with diverse legumes, though the underlying mechanisms remain elusive. This work characterizes the PtsN-KdpDE-KdpFABC pathway that contributes to low potassium adaptation and competitive nodulation of CCBAU45436. Among three PtsN, PtsN1 is the major functional homolog. The unphosphorylated PtsN1 binds the sensory kinase KdpD through a non-canonical interaction with the GAF domain of KdpD, while the region covering HisKA-HATPase domains mediates the interaction of KdpD with the response regulator KdpE. KdpE directly activates the kdpFABC operon encoding the conserved high-affinity potassium uptake system. Disruption of this signaling pathway leads to reduced nodule number, nodule occupancy, and low potassium adaptation ability, but without notable effects on rhizoplane colonization. The induction of key nodulation genes NIN and ENOD40 in host roots during early symbiotic interactions is impaired when inoculating the kdpBC mutant that shows delayed nodulation. The nodulation defect of the kdpBC mutant can be rescued by supplying replete potassium. Potassium is actively consumed by both prokaryotes and eukaryotes, and components of the PTSNtr-KdpDE-KdpFABC pathway are widely conserved in bacteria, highlighting the global importance of this pathway in bacteria-host interactions. IMPORTANCE In all ecological niches, potassium is actively consumed by diverse prokaryotes and their interacting eukaryote hosts. It is only just emerging that potassium is a key player in host-pathogen interactions, and the role of potassium in mutualistic interactions remains largely unknown. This work is focused on the mutualistic symbiosis between rhizobia and legumes. We report that the nitrogen-related phosphotransferase system PTSNtr, the two-component system KdpDE, and the high-affinity potassium uptake system KdpFABC constitute a pathway that is important for low potassium adaptation and optimal nodulation of rhizobia. Given the widely conserved PTSNtr, KdpDE, and KdpFABC in bacteria and increasing knowledge on microbiome for various niches, the PTSNtr-KdpDE-KdpFABC pathway can be globally important in the biosphere.


Asunto(s)
Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato , Rhizobium , Sinorhizobium fredii , Regulación Bacteriana de la Expresión Génica , Nitrógeno/metabolismo , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/metabolismo , Fosforilación , Fosfotransferasas/genética , Potasio/metabolismo , Rhizobium/metabolismo , Sinorhizobium fredii/metabolismo , Simbiosis
19.
Front Nutr ; 9: 846659, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35433793

RESUMEN

Background and Aims: Malnutrition is a well known risk factor for adverse outcomes in patients with cancer, cardiovascular disease (CVD) and chronic kidney disease, but epidemiological evidence on its relationship with the long-term risk of all-cause mortality and cardiovascular death is limited. Methods: A total of 20,116 adults from the United States National Health and Nutrition Examination Survey 2007-2014 were enrolled. The Geriatric Nutritional Risk Index (GNRI), Prognostic Nutritional Index (PNI), Controlling Nutritional Status (CONUT) score, and Triglycerides (TG) × Total Cholesterol (TC) × Body Weight (BW) Index (TCBI) were calculated at baseline. Cox regression and the Kaplan-Meier analysis were conducted when participants were divided into three groups according to the tertiles of objective nutritional scores. Restricted cubic spline was performed to further explore the shape of the relationship between all-cause mortality, cardiovascular death, and nutritional scores. In addition, the area under the curve (AUC), continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were conducted to assess which nutritional scores have the greatest predictive value for all-cause death and cardiovascular death in the general population. Results: The cumulative incidence of all-cause death and cardiovascular death was significantly higher in participants with a higher CONUT score, lower GNRI, and lower PNI. TCBI showed the worst performance on grading and risk assessment. After adjusting confounding factors, the lowest PNI and GNRI tertile and highest COUNT score were independently and significantly associated with increased risk of all-cause death (all P < 0.01) and cardiovascular death (all P < 0.05) analyzed by a multivariate Cox regression model. An L-shaped association between the HR (hazard ratio) of all-cause mortality and nutritional scores (GNRI, PNI and TCBI) was observed in the overall populations. In addition, the PNI had the highest predictive value for all-cause mortality [AUC: 0.684, 95% confidence interval (CI): 0.667-0.701] and cardiovascular death (AUC: 0.710, 95% CI: 0.672-0.749) in the general population compared with other nutritional scores. Conclusion: The poorer the nutritional status of the general population, the higher the all-cause mortality and cardiovascular mortality. The PNI score may provide more useful predictive values than other nutritional scores.

20.
J Hazard Mater ; 433: 128826, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35381513

RESUMEN

A 100-day soil incubation experiment was conducted to explore the effects of conventional (high-density polyethylene, HDPE) and biodegradable (polylactic acid, PLA) microplastics (MPs) and multiwall carbon nanotubes (MWCNTs) on soil geochemical properties and bacterial communities. Generally, soil pH was increased by 10% HDPE and 10% PLA, but decreased by increasing MWCNTs. Soil dissolved organic carbon content was only increased by 10% PLA. NO3--N content was significantly decreased by MPs, with a decrement of 99% by 10% PLA. Similarly, available P content was reduced by 10% MPs. The activities of urease and alkaline phosphatase were stimulated by 10% PLA, but generally inhibited by HDPE. Conversely, FDAse activity was stimulated by HDPE, but inhibited by 10% PLA, whereas invertase activity decreased with increasing MWCNTs. Overall, both MPs and MWCNTs changed soil bacterial diversity. Co-exposure to 10% MPs and MWCNTs of 1 and 10 mg/kg caused the lowest species richness and Shannon indexes. MPs especially at the 10% dose changed bacterial community composition and the associated metabolic pathways, causing the enrichment of specific taxa and functional genes. Our findings show that conventional and biodegradable MPs differently change soil geochemical properties and microbial community structure and functions, which can be further modified by co-existing MWCNTs.


Asunto(s)
Nanotubos de Carbono , Suelo , Bacterias/genética , Microplásticos , Nanotubos de Carbono/toxicidad , Plásticos , Poliésteres , Polietileno , Suelo/química , Microbiología del Suelo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...