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1.
Cell ; 186(17): 3593-3605.e12, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37516107

RESUMEN

Animal fertilization relies on hundreds of sperm racing toward the egg, whereas, in angiosperms, only two sperm cells are delivered by a pollen tube to the female gametes (egg cell and central cell) for double fertilization. However, unsuccessful fertilization under this one-pollen-tube design can be detrimental to seed production and plant survival. To mitigate this risk, unfertilized-gamete-controlled extra pollen tube entry has been evolved to bring more sperm cells and salvage fertilization. Despite its importance, the underlying molecular mechanism of this phenomenon remains unclear. In this study, we report that, in Arabidopsis, the central cell secretes peptides SALVAGER1 and SALVAGER2 in a directional manner to attract pollen tubes when the synergid-dependent attraction fails or is terminated by pollen tubes carrying infertile sperm cells. Moreover, loss of SALs impairs the fertilization recovery capacity of the ovules. Therefore, this research uncovers a female gamete-attraction system that salvages seed production for reproductive assurance.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Animales , Arabidopsis/fisiología , Fertilización , Tubo Polínico , Semillas , Células Germinativas de las Plantas
2.
Opt Express ; 32(6): 8723-8735, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571123

RESUMEN

In this study, a Si defect structure was added into the silica network in order to activate the bismuth and silica structure active center. TD-DFT theoretical simulations show that the Bi and Si ODC(I) models can excite the active center of the E-band at 1408 nm. Additionally, the Bi-doped silica fiber (BDSF) with improved fluorescence was fabricated using atomic layer deposition (ALD) combined with the modified chemical vapor deposition (MCVD) technique. Some tests were used to investigate the structural and optical properties of BDSF. The UV-VIS spectral peak of the BDSF preform is 424 cm-1, and the binding energy of XPS is 439.3 eV, indicating the presence of Bi° atom in BDSF. The Raman peak near 811 cm-1 corresponds to the Bi-O bond. The Si POL defect lacks a Bi-O structure, and the reason for the absence of simulated active center from the E-band is explained. A fluorescence spectrometer was used to analyze the emission peak of a BDSF at 1420 nm. The gain of the BDSF based optical amplifier was measured 28.8 dB at 1420 nm and confirmed the effective stimulation of the bismuth active center in the E-band.

3.
Opt Express ; 32(6): 8937-8949, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571139

RESUMEN

In this study, PbS/Er co-doped fibers (PEDFs) were fabricated by atomic layer deposition (ALD) combined with modified chemical vapor deposition (MCVD). A pumping scheme based on two-photon absorption at 1310 nm of PEDF is proposed for L + band amplification. Through the theoretical analysis, the local environment of Er3+ is changed due to the co-doping of PbS, which improves the two-photon absorption efficiency near 1300 nm. Compared with the 980 nm pump, the PEDFs excited by the 1310 nm pump show better amplification performance in the L + band. And in a bi-directional pumping system, PEDF achieves over 22 dB of gain in the whole L band. In particular, the bandwidth of over 20 dB gain was extended to 1627 nm with a noise figure as low as 4.9 dB. To the best of our knowledge, this is the first time that a high-gain bandwidth of L band amplification has been extended to 1627 nm. The results of unsaturated loss also show that PbS co-doping improves the two-photon absorption efficiency of PEDF to broaden the amplification bandwidth of L + band. These results demonstrate that an effective L + band amplification method is practically provided for future ultra-wideband optical communications.

4.
Glob Chang Biol ; 30(3): e17213, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38436125

RESUMEN

Paddy fields serve as significant reservoirs of soil organic carbon (SOC) and their potential for terrestrial carbon (C) sequestration is closely associated with changes in SOC pools. However, there has been a dearth of comprehensive studies quantifying changes in SOC pools following extended periods of rice cultivation across a broad geographical scale. Using 104 rice paddy sampling sites that have been in continuous cultivation since the 1980s across China, we studied the changes in topsoil (0-20 cm) labile organic C (LOC I), semi-labile organic C (LOC II), recalcitrant organic C (ROC), and total SOC. We found a substantial increase in both the content (48%) and density (39%) of total SOC within China's paddy fields between the 1980s to the 2010s. Intriguingly, the rate of increase in content and density of ROC exceeded that of LOC (I and II). Using a structural equation model, we revealed that changes in the content and density of total SOC were mainly driven by corresponding shifts in ROC, which are influenced both directly and indirectly by climatic and soil physicochemical factors; in particular temperature, precipitation, phosphorous (P) and clay content. We also showed that the δ13 CLOC were greater than δ13 CROC , independent of the rice cropping region, and that there was a significant positive correlation between δ13 CSOC and δ13 Cstraw . The δ13 CLOC and δ13 CSOC showed significantly negative correlation with soil total Si, suggesting that soil Si plays a part in the allocation of C into different SOC pools, and its turnover or stabilization. Our study underscores that the global C sequestration of the paddy fields mainly stems from the substantial increase in ROC pool.


Asunto(s)
Oryza , Suelo , Carbono , China , Geografía
5.
Environ Res ; 246: 118070, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38157962

RESUMEN

BACKGROUND: Type 2 diabetes (T2D) is the most common type of diabetes. However, research on the relationship between blue light exposure and diabetes development is limited. OBJECTIVE: The present study aimed to investigate the relationship between blue light exposure and T2D incidence and whether it is affected by sleep duration, physical activity, outdoor activity time, and genetic susceptibility. METHODS: A total of 471,686 participants without diabetes were recruited from the UK Biobank cohort. T2D incidence was assessed using hospital inpatient records. Blue light exposure was calculated based on the time spent watching TV, using a computer, and playing computer games, which was determined using an online questionnaire. Cox proportional hazards regression models were used to assess the survival relationship between blue light exposure and T2D, as well as the potential modification effects. RESULT: A total of 18,738 cases of T2D were documented during the median follow-up of 13.04 years. After adjusting for potential confounders, the participants with heavy blue light exposure had a greater risk of T2D compared to those with mild blue light exposure (hazard ratio (HR) = 1.17, 95% confidence interval (CI): 1.12-1.23). A significant association between blue light exposure and T2D risk was observed among the participants with heavy physical activity (HR = 1.39, 95%CI: 1.25-1.55), healthy sleep habits (HR = 1.23, 95%CI: 1.10-1.36), higher outdoor activity time (HR = 1.14, 95%CI: 1.07-1.22), or high genetic susceptibility (HR = 1.24, 95%CI: 1.14-1.35). However, this association became non-significant among the participants with low genetic susceptibility (HR = 1.05, 95%CI: 0.97-1.15). CONCLUSION: The present study showed that blue light exposure is associated with a greater risk of T2D independent of classical T2D risk factors.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/etiología , Estudios Prospectivos , Factores de Riesgo , Incidencia , Bancos de Muestras Biológicas , Luz Azul , Biobanco del Reino Unido , Predisposición Genética a la Enfermedad
6.
Environ Res ; 245: 118011, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38141916

RESUMEN

Microbes have been confirmed to play key role in biogeochemistry of antimony. However, the impact of indigenous bacteria (from active mines) on the behavior of dissolved antimony remained poorly understood. In current study, the hyper antimony-resistant strain, Achromobacter sp. 25-M, isolated from the world largest antimony deposit, Xikuangshan antimony deposit, was evaluated for its role in dissolved Sb(V) and Sb(III) precipitation and removal. Despite of the high resistance to Sb(III) (up to 50 mM), the facultative alkaliphile, 25-M was not capable of Sb(III) oxidation. Meanwhile 25-M can produce high amount of exopolymeric substance (EPS) with the presence of Sb, which prompted us to investigate the potential role of EPS in the precipitation and removal of Sb. To this end, 2 mM of Sb(III) and Sb(V) were added into the experimental systems with and without 25-M to discern the interaction mechanism between microbe and antimony. After 96 hrs' incubation, 88% [1.73 mM (210 mg/L)] of dissolved Sb(V) and 80% [1.57 mM (190 mg/L)] of dissolved Sb(III) were removed. X-ray diffraction and energy dispersive spectroscopy analysis confirmed the formation of valentinite (Sb2O3) in Sb(III) amended system and a solitary Sb(V) mineral mopungite [NaSb(OH)6] in Sb(V) amended group with microbes. Conversely, no precipitate was detected in abiotic systems. Morphologically valentinite was bowtie and mopungite was pseudo-cubic as indicated by scanning electronic microscopy. EPS was subjected to fourier transform infrared (FT-IR) analysis. FT-IR analysis suggested that -OH and -COO groups were responsible for the complexation and ligand exchange with Sb(III) and Sb(V), respectively. Additionally, the C-H group and N-H group could be involved in π-π interaction and chelation with Sb species. All these interactions between Sb and functional groups in EPS may subsequently favore the formation of valentinite and mopungite. Collectively, current results suggested that EPS play fundamental role in bioprecipitation of Sb, which offered a new strategy in Sb bioremediation.


Asunto(s)
Antimonio , Minerales , Antimonio/química , Espectroscopía Infrarroja por Transformada de Fourier , Oxidación-Reducción , Difracción de Rayos X , Adsorción
7.
J Craniofac Surg ; 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38809062

RESUMEN

Despite their limitations, epidemiological studies provide information useful for formulating effective and efficient injury prevention strategies. The aim is to carry out an epidemiology study of maxillofacial fracture in Xijing Hospital. Level of Evidence: Level II-therapeutic study.

8.
Sensors (Basel) ; 24(4)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38400261

RESUMEN

In the field of inter-satellite laser communication, achieving high-quality communication and compensating for the Doppler frequency shift caused by relative motion necessitate lasers with narrow linewidths, low phase noise, and the ability to achieve mode-hop-free tuning within a specific range. To this end, this paper investigates a novel external cavity diode laser (ECDL) with a frequency-selective F-P etalon structure, leveraging the external cavity F-P etalon structure in conjunction with an auxiliary filter to achieve single longitudinal mode selection. The laser undergoes linewidth testing using a delayed self-heterodyne beating method, followed by the testing of its phase noise and frequency noise characteristics using a noise analyzer, yielding beat spectra and noise power spectral density profiles. Furthermore, the paper introduces an innovative bidirectional temperature-scanning laser method to achieve optimal laser-operating point selection and mode-hop-free tuning. The experimental results showcase that the single longitudinal mode spectral side-mode suppression ratio (SMSR) is around 70 dB, and the output power exceeds 10 mW. Enhancing the precision of the F-P etalon leads to a more pronounced suppression of low-frequency phase noise, reducing the Lorentzian linewidth from the initial 10 kHz level to a remarkable 5 kHz level. The bidirectional temperature-scanning laser method not only allows for the selection of the optimal operating point but also enables mode-hop-free tuning within 160 pm.

9.
Proc Biol Sci ; 290(1997): 20230406, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37072036

RESUMEN

Bird observation mainly relies on field surveys, which are time-consuming and laborious. In this study, we explored using street-view images in the virtual survey of urban birds and nests. Using the coastal city of Qingdao as the study area, 47 201 seamless spherical photos at 2741 sites were collected using the Baidu street-view (BSV) map. Single-rater-all photo checks and seven-rater-metapopulation checks were used to find inter-rater repeatability, the best viewing layer for BSV collection, and possible environments affecting the results. We also collected community science data for comparison. The BSV time machine was used to assess the temporal dynamics. Kappa square test, generalized linear model, redundancy ordination and ArcMap were used in the analysis. Different rater repeatability was 79.1% in nest evaluations and 46.9% in bird occurrence. A re-check of the different-rating photos can increase them to 92% and 70%. Seven-rater statistics showed that more than 5% sampling ratio could produce a non-significant different bird and nest percentage of the whole data, and the higher sampling ratio could reduce the variation. The middle-viewing layer survey alone could produce 93% precision of the nest checks by saving 2/3 of the time used; in birds, selecting middle and upper-view photos could find 97% of bird occurrences. In the spatial distribution, the nest's hotspot areas from this method were much greater than the community science bird-watching sites. The BSV time machine made it possible to re-check nests in the same sites but challenging the re-check of bird occurrences. The nests and birds can be observed more in the leafless season, on wide, traffic-dense coastal streets with complex vertical structures of trees, and in the gaps of tall buildings dominated by road forests. Our results indicate that BSV photos could be used to virtually evaluate bird occurrence and nests from their numbers, spatial distribution and temporal dynamics. This method provides a pre-experimental and informative supplement to large-scale bird occurrence and nest abundance surveys in urban environments.


Asunto(s)
Bosques , Comportamiento de Nidificación , Animales , Estudios de Factibilidad , Árboles , Aves
10.
Opt Express ; 31(9): 14862-14872, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37157341

RESUMEN

In this work, bismuth doped fiber (BDF) and bismuth/phosphosilicate co-doped fiber (BPDF) were fabricated by atomic layer deposition (ALD) combined with the modified chemical vapor deposition (MCVD). The spectral characteristics are studied experimentally and the BPDF has good excitation effect covering the O band. A diode pumped BPDF amplifier with the gain over 20 dB from 1298-1348 nm (50 nm) has been demonstrated. The maximum gain of 30 dB was measured at 1320 nm with a gain coefficient of around 0.5 dB/m. Furthermore, we constructed different local structures through simulation and found that compared with the BDF, BPDF has a stronger excited state and a greater significance in O-band. This is mainly because phosphorus (P) doping changes the associated electron distribution and forms the bismuth-phosphorus active center. The fiber has a high gain coefficient, which is of great significance for the industrialization of O-band fiber amplifier.

11.
Environ Sci Technol ; 57(22): 8323-8334, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37216216

RESUMEN

Cr(VI) detoxification and organic matter (OM) stabilization are usually influenced by the biological transformation of iron (Fe) minerals; however, the underlying mechanisms of metal-reducing bacteria on the coupled kinetics of Fe minerals, Cr, and OM remain unclear. Here, the reductive sequestration of Cr(VI) and immobilization of fulvic acid (FA) during the microbially mediated phase transformation of ferrihydrite with varying Cr/Fe ratios were investigated. No phase transformation occurred until Cr(VI) was completely reduced, and the ferrihydrite transformation rate decreased as the Cr/Fe ratio increased. Microscopic analysis was uncovered, which revealed that the resulting Cr(III) was incorporated into the lattice structure of magnetite and goethite, whereas OM was mainly adsorbed on goethite and magnetite surfaces and located within pore spaces. Fine line scan profiles showed that OM adsorbed on the Fe mineral surface had a lower oxidation state than that within nanopores, and C adsorbed on the magnetite surface had the highest oxidation state. During reductive transformation, the immobilization of FA by Fe minerals was predominantly via surface complexation, and OM with highly aromatic and unsaturated structures and low H/C ratios was easily adsorbed by Fe minerals or decomposed by bacteria, whereas Cr/Fe ratios had little effect on the binding of Fe minerals and OM and the variations in OM components. Owing to the inhibition of crystalline Fe minerals and nanopore formation in the presence of Cr, Cr sequestration and C immobilization can be synchronously favored at low Cr/Fe ratios. These findings provide a profound theoretical basis for Cr detoxification and synchronous sequestration of Cr and C in anoxic soils and sediments.


Asunto(s)
Óxido Ferrosoférrico , Minerales , Minerales/química , Compuestos Férricos/química , Cromo/química , Oxidación-Reducción
12.
Environ Res ; 229: 115966, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37100368

RESUMEN

BACKGROUND: Environmental stresses pose a significant threat to plant growth and ecosystem productivity, particularly in arid lands that are more susceptible to climate change. Strigolactones (SLs), carotenoid-derived plant hormones, have emerged as a potential tool for mitigating environmental stresses. METHODS: This review aimed to gather information on SLs' role in enhancing plant tolerance to ecological stresses and their possible use in improving the resistance mechanisms of arid land plant species to intense aridity in the face of climate change. RESULTS: Roots exude SLs under different environmental stresses, including macronutrient deficiency, especially phosphorus (P), which facilitates a symbiotic association with arbuscular mycorrhiza fungi (AMF). SLs, in association with AMF, improve root system architecture, nutrient acquisition, water uptake, stomatal conductance, antioxidant mechanisms, morphological traits, and overall stress tolerance in plants. Transcriptomic analysis revealed that SL-mediated acclimatization to abiotic stresses involves multiple hormonal pathways, including abscisic acid (ABA), cytokinins (CK), gibberellic acid (GA), and auxin. However, most of the experiments have been conducted on crops, and little attention has been paid to the dominant vegetation in arid lands that plays a crucial role in reducing soil erosion, desertification, and land degradation. All the environmental gradients (nutrient starvation, drought, salinity, and temperature) that trigger SL biosynthesis/exudation prevail in arid regions. The above-mentioned functions of SLs can potentially be used to improve vegetation restoration and sustainable agriculture. CONCLUSIONS: Present review concluded that knowledge on SL-mediated tolerance in plants is developed, but still in-depth research is needed on downstream signaling components in plants, SL molecular mechanisms and physiological interactions, efficient methods of synthetic SLs production, and their effective application in field conditions. This review also invites researchers to explore the possible application of SLs in improving the survival rate of indigenous vegetation in arid lands, which can potentially help combat land degradation problems.


Asunto(s)
Ecosistema , Reguladores del Crecimiento de las Plantas , Reguladores del Crecimiento de las Plantas/metabolismo , Lactonas/metabolismo , Plantas , Estrés Fisiológico
13.
J Chem Phys ; 159(14)2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37811831

RESUMEN

In this work, we present a full-dimensional potential energy surface for AlF-AlF. We apply a general machine learning approach for full-dimensional potential energy surfaces, employing an active learning scheme trained on ab initio points, whose size grows based on the accuracy required. The training points are selected based on molecular dynamics simulations, choosing the most suitable configurations for different collision energy and mapping the most relevant part of the potential energy landscape of the system. The present approach does not require long-range information and is entirely general. As a result, it is possible to provide the full-dimensional AlF-AlF potential energy surface, requiring ≲0.01% of the configurations to be calculated ab initio. Furthermore, we analyze the general properties of the AlF-AlF system, finding critical differences with other reported results on CaF or bi-alkali dimers.

14.
Med Sci Monit ; 29: e940545, 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38062672

RESUMEN

BACKGROUND Large cancer lesions are often challenging to treat with surgical intervention alone. Neoadjuvant chemotherapy is frequently used for FIGO stage IB3 and IIA2 cervical cancers to optimize the outcomes of radical surgeries. This study aimed to compare the effectiveness of neoadjuvant chemotherapy, followed by adjuvant chemotherapy and radiotherapy, if necessary, with the traditional approach of adjuvant chemotherapy and radiotherapy after radical hysterectomy in treatment-naïve patients with cervical cancer of specified stages. MATERIAL AND METHODS A total of 245 female patients were administered either 70 to 85 mg/m² cisplatin and 165 to 175 mg/m² paclitaxel every 21 days (2 cycles) prior to radical hysterectomy, followed by adjuvant chemotherapy and radiotherapy if needed (neoadjuvant therapy, NT cohort, n=105), or received adjuvant chemotherapy and radiotherapy after radical hysterectomy adjuvant therapy, AT cohort, n=140). RESULTS In the NT cohort, 76% of patients responded to neoadjuvant chemotherapy, while 24% did not. Adverse operative, intraoperative, and postoperative outcomes were significantly more common among the non-responders (P<0.05). After 5 years, 91% of responders and 72% of non-responders survived without recurrence (P=0.0372), and 3% of responders and 28% of non-responders had died (P=0.0005). CONCLUSIONS The resistance to neoadjuvant chemotherapy is a poor prognostic factor. Neoadjuvant chemotherapy followed by radical hysterectomy and adjuvant chemotherapy/radiotherapy appears to be advantageous for cervical cancer patients who respond well to neoadjuvant chemotherapy.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Cuello Uterino , Humanos , Femenino , Terapia Neoadyuvante/métodos , Cisplatino/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , Estadificación de Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Paclitaxel/uso terapéutico , Quimioterapia Adyuvante , Histerectomía/métodos
15.
New Microbiol ; 46(2): 186-195, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37247239

RESUMEN

Currently, the infection of hypervirulent Klebsiella pneumoniae (hvKp) is becoming increasingly serious and the virulent mechanisms of hvKp are still not very clear. An effective gene-editing method for genes on hvKp virulence plasmid can help us reveal related virulent mechanisms. There are a few reports focusing on the methods mentioned above, however with certain limitations. In this work, we first constructed the pRE112-basing recombinant suicide plasmid to knock out or replace the genes in the hvKp virulence plasmid based on the principle of homology recombination. Results showed that the target virulent genes iucA, iucB, iroB, and rmpA2 on the hvKp virulence plasmid were scarlessly knocked out or replaced by marker genes, and mutant hvKp strains with the expected phenotypes were obtained. These indicated that we established an efficient gene-editing method for genes on hvKp virulence plasmid, which could help us explore the functions of these genes and reveal the virulent mechanisms of hvKp.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Humanos , Virulencia/genética , Klebsiella pneumoniae/genética , Plásmidos/genética , Infecciones por Klebsiella/tratamiento farmacológico , Antibacterianos/uso terapéutico
16.
Molecules ; 29(1)2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38202805

RESUMEN

AlF is a relevant molecule in astrochemistry as a tracer of F-bearing molecules. Additionally, AlF presents diagonal Franck-Condon factors and can be created very efficiently in the lab, which makes it a prototypical molecular for laser cooling. However, very little is known about the reaction dynamics of AlF. In this work, we report on the reaction dynamics of AlF-AlF between 200 and 1000 K using ab initio molecular dynamics and a highly efficient active learning approach for the potential energy surface, including all degrees of freedom. As a result, we identify the main reaction mechanisms and the lifetime of the intermediate complex AlF-AlF relevant to astrochemistry environments and regions in buffer gas cells.

17.
Glob Chang Biol ; 28(20): 6065-6085, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35771205

RESUMEN

Soil organic carbon (SOC) in coastal wetlands, also known as "blue C," is an essential component of the global C cycles. To gain a detailed insight into blue C storage and controlling factors, we studied 142 sites across ca. 5000 km of coastal wetlands, covering temperate, subtropical, and tropical climates in China. The wetlands represented six vegetation types (Phragmites australis, mixed of P. australis and Suaeda, single Suaeda, Spartina alterniflora, mangrove [Kandelia obovata and Avicennia marina], tidal flat) and three vegetation types invaded by S. alterniflora (P. australis, K. obovata, A. marina). Our results revealed large spatial heterogeneity in SOC density of the top 1-m ranging 40-200 Mg C ha-1 , with higher values in mid-latitude regions (25-30° N) compared with those in both low- (20°N) and high-latitude (38-40°N) regions. Vegetation type influenced SOC density, with P. australis and S. alterniflora having the largest SOC density, followed by mangrove, mixed P. australis and Suaeda, single Suaeda and tidal flat. SOC density increased by 6.25 Mg ha-1 following S. alterniflora invasion into P. australis community but decreased by 28.56 and 8.17 Mg ha-1 following invasion into K. obovata and A. marina communities. Based on field measurements and published literature, we calculated a total inventory of 57 × 106 Mg C in the top 1-m soil across China's coastal wetlands. Edaphic variables controlled SOC content, with soil chemical properties explaining the largest variance in SOC content. Climate did not control SOC content but had a strong interactive effect with edaphic variables. Plant biomass and quality traits were a minor contributor in regulating SOC content, highlighting the importance of quantity and quality of OC inputs and the balance between production and degradation within the coastal wetlands. These findings provide new insights into blue C stabilization mechanisms and sequestration capacity in coastal wetlands.


Asunto(s)
Carbono , Humedales , Carbono/análisis , China , Especies Introducidas , Poaceae/fisiología , Suelo/química
18.
Inflamm Res ; 71(2): 227-241, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34993560

RESUMEN

OBJECTIVE: Trimetazidine (TMZ) exerts a strong inhibitory effect on ischemia/reperfusion (I/R) injury. Inflammation plays a key role in I/R injury. We hypothesized that TMZ may protect cardiomyocytes from I/R injury by inhibiting inflammation. METHODS: The left anterior descending coronary artery was ligated for 30 min followed by 6 h of reperfusion to establish a model of I/R injury. H9c2 cardiomyocytes were subjected to 2 h of hypoxia and 3 h of normoxic conditions to establish a model of hypoxia/reoxygenation (H/R) injury. We monitored the change in pyroptosis by performing Western blot analysis, microscopy and ELISA. RESULTS: I/R and H/R treatment stimulated gasdermin D-N domain (GSDMD-N) expression in cardiomyocytes (sham onefold vs. I/R 2.5-fold; control onefold vs. H/R 2.0-fold). Moreover, TMZ increased the viability of H9c2 cardiomyocytes subjected to H/R treatment (H/R 65.0% vs. H/R + TMZ 85.3%) and reduced the infarct size in vivo (I/R 47.0% vs. I/R + TMZ 28.3%). H/R and I/R treatment increased the levels of TLR4, MyD88, phospho-NF-κB p65 and the NLRP3 inflammasome; however, TMZ reduced the expression of these proteins. Additionally, TMZ inhibited noncanonical inflammasome signaling induced by I/R injury. CONCLUSIONS: In summary, TMZ alleviated pyroptosis induced by myocardial I/R injury through the TLR4/MyD88/NF-κB/NLRP3 inflammasome pathway. Therefore, TMZ represents an alternative treatment for myocardial I/R injury.


Asunto(s)
Daño por Reperfusión Miocárdica/tratamiento farmacológico , Proteínas de Unión a Fosfato/antagonistas & inhibidores , Proteínas Citotóxicas Formadoras de Poros/antagonistas & inhibidores , Piroptosis/efectos de los fármacos , Trimetazidina/farmacología , Animales , Masculino , Daño por Reperfusión Miocárdica/patología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , FN-kappa B/fisiología , Proteína con Dominio Pirina 3 de la Familia NLR/fisiología , Proteínas de Unión a Fosfato/fisiología , Proteínas Citotóxicas Formadoras de Poros/fisiología , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/fisiología
19.
BMC Cardiovasc Disord ; 22(1): 554, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36544106

RESUMEN

BACKGROUND: Acute myocardial infarction (AMI) is one of the leading contributors to morbidity and mortality worldwide, with a prevalence of nearly three million people, and more than one million deaths reported in the United States every year. Gasdermin D (GSDMD) is involved in the development of atherosclerosis as a key protein of proptosis. This study was designed to determine the potential relationship of GSDMD with AMI in Chinese patients. METHODS: One hundred patients with AMI and 50 controls were consecutively enrolled in this prospective observational study. GSDMD expression levels and other clinical variables in peripheral blood mononuclear cells (PBMCs) were measured upon admission to the hospital. All patients were followed up for 360 days, and the endpoint was considered the occurrence of major adverse cardiovascular events (MACE). RESULTS: GSDMD expression levels in the PBMCs of patients with AMI were significantly higher than those in the controls. Moreover, our analysis showed that GSDMD was an independent biomarker of AMI and had a promising diagnostic ability for it. Finally, the results suggested that high expression of GSDMD and diabetes increased the risk of MACE after AMI. CONCLUSIONS: This study indicated that the GSDMD expression level in PBMCs was elevated in AMI patients and was closely associated with the pyroptosis of AMI.


Asunto(s)
Gasderminas , Infarto del Miocardio , Humanos , Biomarcadores , Diabetes Mellitus/metabolismo , Gasderminas/sangre , Gasderminas/metabolismo , Leucocitos Mononucleares , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/metabolismo , Complicaciones de la Diabetes
20.
J Nanobiotechnology ; 20(1): 207, 2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35501794

RESUMEN

As a typical class of crystalline porous materials, metal-organic framework possesses unique features including versatile functionality, structural and compositional tunability. After being reduced to two-dimension, ultrathin metal-organic framework layers possess more external excellent properties favoring various technological applications. In this review article, the unique structural properties of the ultrathin metal-organic framework nanosheets benefiting from the planar topography were highlighted, involving light transmittance, and electrical conductivity. Moreover, the design strategy and versatile fabrication methodology were summarized covering discussions on their applicability and accessibility, especially for porphyritic metal-organic framework nanosheet. The current achievements in the bioapplications of two-dimensional metal-organic frameworks were presented comprising biocatalysis, biosensor, and theranostic, with an emphasis on reactive oxygen species-based nanomedicine for oncology treatment. Furthermore, current challenges confronting the utilization of two-dimensional metal-organic frameworks and future opportunities in emerging research frontiers were presented.


Asunto(s)
Estructuras Metalorgánicas , Biocatálisis , Conductividad Eléctrica , Nanomedicina , Porosidad
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