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1.
Shanghai Kou Qiang Yi Xue ; 33(2): 164-169, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-39005093

RESUMEN

PURPOSE: The characteristics of saliva and intestinal microbial community in children with high caries and no caries were analyzed by 16S rDNA high-throughput sequencing. METHODS: Among 431 children aged 3-5 years old in Zunyi City who were investigated previously by our team, 25 children in the high caries group and the same in the caries-free group were selected for fecal and saliva samples. 16S rDNA high-throughput sequencing was used to analyze the bacterial flora structure of the samples and identify the species with different relative abundance at the species level. SPSS 18.0 software package was used for data analysis. RESULTS: The diversity of intestinal flora in the high caries group was higher than that in the caries-free group, and the difference was statistically significant(P<0.05). The diversity of salivary flora in the high caries group was more than that in the caries-free group, with no significant difference(P>0.05). At phylum level,there was no significant difference in intestinal and salivary flora between children with high caries and children without caries. At gene level, Blautia, [Eubacterium] hallii group and [Eubacterium] eligens group in the intestine of caries-free group were significantly higher than those of high caries group(P<0.05), while Parasutterella and Christensenellaceae R-7 group were significantly lower than those of high caries group(P<0.05). At gene level, Peptostreptococcus in saliva of caries-free group was significantly higher than that in high caries group(P<0.05). Dialister, Kingella, Escherichia-Shigella and Treponema in saliva of caries-free group were significantly lower than those in high caries group(P<0.05). CONCLUSIONS: There are significant differences in species composition of intestinal flora but no in salivary flora between children with high caries and children without caries.


Asunto(s)
Caries Dental , Microbioma Gastrointestinal , Secuenciación de Nucleótidos de Alto Rendimiento , ARN Ribosómico 16S , Saliva , Humanos , Saliva/microbiología , Caries Dental/microbiología , Preescolar , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , ARN Ribosómico 16S/genética , Microbioma Gastrointestinal/genética , Heces/microbiología , Eubacterium/genética , ADN Bacteriano/genética , ADN Ribosómico/genética
2.
Drug Des Devel Ther ; 18: 2435-2447, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38915864

RESUMEN

Purpose: SN-38 (7-ethyl-10-hydroxycamptothecin), the active metabolite of irinotecan, has been extensively studied in drug delivery systems. However, its impact on neural metabolism remains unclear. This study aims to investigate the toxic effects of SN-38 on mouse brain metabolism. Methods: Male mice were divided into an SN-38 group and a control group. The SN-38 group received SN-38 (20 mg/kg/day) via intraperitoneal injection, while the control group was given an equal volume of a blank solvent mixture (DMSO and saline, ratio 1:9). Gas chromatography-mass spectrometry (GC-MS) was employed to analyze differential metabolites in the cortical and hippocampal regions of the SN-38-treated mice. Results: SN-38 induced metabolic disturbances in the central nervous system. Eighteen differential metabolites were identified in the hippocampus and twenty-four in the cortex, with six common to both regions. KEGG pathway enrichment analysis revealed statistically significant alterations in six metabolic pathways in the hippocampus and ten in the cortex (P<0.05). Conclusion: This study is the first to demonstrate the neurotoxicity of SN-38 in male mice through metabolomics. Differential metabolites in the hippocampal and cortical regions were closely linked to purine metabolism, pyrimidine metabolism, amino acid metabolism, and glyceride metabolism, indicating disruptions in the blood-brain barrier, energy metabolism, and central signaling pathways.


Asunto(s)
Encéfalo , Irinotecán , Metabolómica , Animales , Masculino , Irinotecán/farmacología , Ratones , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Inyecciones Intraperitoneales
3.
Environ Sci Technol Lett ; 11(6): 626-633, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38882201

RESUMEN

Decades-long emissions and long-range transport of chlorinated paraffins (CPs) have resulted in their pervasive presence in the global environment. The lack of an understanding of the global distribution of short-, medium-, and long-chain CPs (SCCPs, MCCPs, and LCCPs) hinders us from quantitatively tracing their origins in remote regions. Using the BETR-Global model and historical emission estimates, we simulate the global dispersion of CPs from 1930 to 2020. Whereas contamination trends in the main contaminated regions (East Asia, Europe, North America, and South Asia) diverge, CP concentrations in the Arctic, Antarctica, and the Tibetan Plateau all increase. By 2020, East Asian, European, and North American emissions contributed 38%, 26%, and 18% of CP contamination in the High Arctic, respectively, while Southern hemispheric emissions and emissions around the Tibetan Plateau primarily contribute to CP contamination in central Antarctica and on the Plateau, respectively. Our results emphasize the important contribution of (i) European and North American emissions to historical CP contamination in remote regions and current MCCP and LCCP contamination in the High Arctic and (ii) East Asian emission to current SCCP and MCCP contamination of all three remote regions. These results can help to evaluate the effectiveness of potential global and regional CP emission-reduction strategies.

4.
Natl Sci Rev ; 11(7): nwae073, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38883306

RESUMEN

Understanding the heterogeneous role of individuals in large-scale information spreading is essential to manage online behavior as well as its potential offline consequences. To this end, most existing studies from diverse research domains focus on the disproportionate role played by highly connected 'hub' individuals. However, we demonstrate here that information superspreaders in online social media are best understood and predicted by simultaneously considering two individual-level behavioral traits: influence and susceptibility. Specifically, we derive a nonlinear network-based algorithm to quantify individuals' influence and susceptibility from multiple spreading event data. By applying the algorithm to large-scale data from Twitter and Weibo, we demonstrate that individuals' estimated influence and susceptibility scores enable predictions of future superspreaders above and beyond network centrality, and reveal new insights into the network positions of the superspreaders.

5.
Appl Opt ; 63(12): 3162-3167, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38856461

RESUMEN

The paper proposes a spot positioning method based on a four-quadrant detector for the limited computing power and memory of spaceborne laser communication, in which the adaptive interpolation segmentation (AIS) algorithm is used to fit the theoretical position curve. The algorithm uses linear operations though the fitting process and the simulated result indicates that it has higher positioning accuracy in the center area of the quadrant detector. A spot receiving and positioning system was built for experimentation and the final location of the spot was calculated. The positioning error is analyzed to evaluate the performance of the whole system. It is shown that the positioning accuracy is highest in the stable communication area of the system. In result, the scheme achieves high accuracy with simple operations, which is more suitable for spaceborne laser communication systems to release more performance for communication.

6.
Appl Opt ; 63(13): 3664-3673, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38856553

RESUMEN

In this paper, a broadband photoelectric fusion transceiver-multiplexed system is proposed to realize a frequency converter. The system achieves a high spurious suppression ratio through two frequency conversions that utilize the advantages of microwave and photonics technology simultaneously to reduce the complexity of the system and improve the effective spectrum utilization. In addition, the core components, such as the Mach-Zehnder modulator (MZM), are multiplexed in the up and down frequency conversion link. High-frequency local oscillator (LO) signals are used to keep image frequency signals and various kinds of spurious signals obtained by beating frequency outside the system bandwidth. Experimental results demonstrate that the operating frequency ranges from 2 to 18 GHz with high performance for both transmitter and receiver. The image rejection is 57.35 dB for up-conversion and 46.56 dB for down-conversion, and the in-band spurious suppression achieves at least 55.02 dB. At the same time, the spurious-free dynamic range (SFDR) can reach at least 89.11d B⋅H z 2/3.

7.
Sci Total Environ ; 945: 173817, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38880139

RESUMEN

Tioxazafen (TXF) is the first 1,2,4-oxadiazole nematicide. In the present study, the aqueous degradation of TXF was investigated in terms of hydrolysis and photolysis. Under the irradiation of simulated sunlight, TXF degraded very fast in ultrapure water and buffers with half-lives (t1/2s) <8.3 min. A sole photoproduct (PP) PP228a was isolated, and identified by spectroscopic means (UV, IR, HRMS, and 1H NMR) to be the thiophen-3-yl isomer converted from its thiophen-2-yl parent. Comparing with TXF, PP228a had quite extended t1/2s ranging from 6.9 to 7.9 d. The photolysis kinetics of TXF and PP228a showed no pH-dependence, and varied for each individual compound as affected by nitrate, fulvic acid, and humic acid. Besides, both compounds were hydrolytically stable. 6 PPs of PP228a were identified, with two of them being its isomers. The mechanisms involved in the process included the biradical photosensitization, photoinduced electron transfer, and ring contraction-ring expansion reactions. The 48 h-EC50 to Daphnia magna was 0.808 mg/L for PP228a comparing to >1.12 mg/L for TXF, while the results of Vibrio fischeri assays indicated that one or more PPs of PP228a might have higher toxicity.


Asunto(s)
Fotólisis , Contaminantes Químicos del Agua , Cinética , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/química , Oxadiazoles/química , Oxadiazoles/toxicidad , Daphnia/efectos de los fármacos , Animales
8.
Nat Ecol Evol ; 8(7): 1365-1377, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38867092

RESUMEN

Understanding species distributions is a global priority for mitigating environmental pressures from human activities. Ample studies have identified key environmental (climate and habitat) predictors and the spatial scales at which they influence species distributions. However, regarding human influence, such understandings are largely lacking. Here, to advance knowledge concerning human influence on species distributions, we systematically reviewed species distribution modelling (SDM) articles and assessed current modelling efforts. We searched 12,854 articles and found only 1,429 articles using human predictors within SDMs. Collectively, these studies of >58,000 species used 2,307 unique human predictors, suggesting that in contrast to environmental predictors, there is no 'rule of thumb' for human predictor selection in SDMs. The number of human predictors used across studies also varied (usually one to four per study). Moreover, nearly half the articles projecting to future climates held human predictors constant over time, risking false optimism about the effects of human activities compared with climate change. Advances in using human predictors in SDMs are paramount for accurately informing and advancing policy, conservation, management and ecology. We show considerable gaps in including human predictors to understand current and future species distributions in the Anthropocene, opening opportunities for new inquiries. We pose 15 questions to advance ecological theory, methods and real-world applications.


Asunto(s)
Cambio Climático , Modelos Biológicos , Humanos , Actividades Humanas , Distribución Animal , Ecosistema , Animales
9.
Heliyon ; 10(7): e28659, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38689999

RESUMEN

Based on the perspective of spatial economy, this paper focuses on the primary effects and spatial characteristics of Digital Financial Inclusion (DFI) on the upgrading of rural consumption structure (URCS) in China, conducting a literature review and theoretical analysis. It then uses statistical data collected over the years and the Digital Financial Inclusion Index (DFII) of Peking University to prepare panel data for 31 provinces in China (aside from Hong Kong, Macao, and Taiwan) from 2011 to 2020 for empirical testing. The results are as follows: DFI can considerably boost URCS, and there is a strong spatial neighbor impact, that is, it is affected by random shocks in surrounding provinces via its spatial effect; DFI has nonlinear characteristics in the process of fostering URCS, with the threshold variables of income level and family sizes; the impact of DFI on URCS is spatially heterogeneous, and the promotion of the eastern region is better than other zones. These results can inform policymakers about rural development and provide valuable references to push forward rural vitalization.

10.
J Orthop Surg (Hong Kong) ; 32(2): 10225536241251926, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38733065

RESUMEN

AIM: To explore the effects of tibial osteotomy varus angle combined with posterior tibial slope (PTS) on the stress of polyethylene liner in total knee arthroplasty (TKA) by building finite element model (FEM). METHODS: Established the FEM of standard TKA with tibial osteotomy varus angle 0° to 9° were established and divided into 10 groups. Next, each group was created 10 FEMs with 0° to 9° PTS separately. Calculated the stress on polyethylene liner in each group in Abaqus. Finally, the relevancy between tibial osteotomy angle and polyethylene liner stress was statistically analyzed using multiple regression analysis. RESULTS: As the varus angle increased, the area of maximum stress gradually shifted medially on the polyethylene liner. As the PTS increases, the percentage of surface contact forces on the medial and lateral compartmental of the polyethylene liner gradually converge to the same. When the varus angle is between 0° and 3°, the maximum stress of the medial compartmental surfaces of polyethylene liner rises smoothly with the increase of the PTS. When the varus angle is between 4° and 9°, as the increase of the PTS, the maximum stress of polyethylene liner rises first and then falls, forming a trough at PTS 5° and then rises again. Compared to the PTS, the varus angle has a large effect on the maximum stress of the polyethylene liner (p < .001). CONCLUSION: When the varus angle is 0° to 3°, PTS 0° is recommended, which will result in a more equalized stress distribution of the polyethylene liner in TKA.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Análisis de Elementos Finitos , Prótesis de la Rodilla , Osteotomía , Polietileno , Estrés Mecánico , Tibia , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Osteotomía/métodos , Tibia/cirugía , Diseño de Prótesis
11.
Clin Exp Dent Res ; 10(3): e885, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38798048

RESUMEN

OBJECTIVES: Calcifying nanoparticles (CNPs), referred to as nanobacteria (NB), are recognized to be associated with ectopic calcification. This study aims to isolate and culture CNPs from the dental plaque of patients with periodontal disease and investigate their possible role in unravelling the aetiology of periodontal disease. MATERIAL AND METHODS: Supragingival and subgingival plaques were sampled from 30 periodontitis patients for CNPs isolation and culture. Alkaline phosphatase (ALP) content changes were tracked over time. Positive samples underwent thorough morphological identification via hematoxylin and eosin (HE) staining, Alizarin red S (ARS), and transmission electron microscopy (TEM). The chemical composition of CNPs analysis involved calcium (Ca) and phosphorus (P) content determination, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). RESULTS: The subgingival plaque dental group exhibited a higher CNPs isolation rate at 36.67% (11/30) compared to the supragingival dental plaque group at 66.67% (20/30). ALP activity varied among the positive, negative and control groups. Morphological observation characterized the CNPs as round, oval, and ellipsoid particles with Ca deposits. Chemical analysis revealed the Ca/P ratio was 0.6753. Hydroxyl, methyl, carbonate, phosphate, hydrogen phosphate, and dihydrogen phosphate were detected by FTIR; the main chemical components detected by XRD were hydroxyapatite and tricalcium phosphate. CONCLUSION: CNPs were found in periodontitis-related dental plaque and exhibited the potential to develop calcified structures resembling dental calculus. However, the potential involvement of ALP in CNPs formation requires deeper exploration, as does the precise nature of its role and the interrelation with periodontitis demand a further comprehensive investigation.


Asunto(s)
Fosfatasa Alcalina , Nanopartículas Calcificantes , Placa Dental , Difracción de Rayos X , Humanos , Nanopartículas Calcificantes/metabolismo , Placa Dental/microbiología , Placa Dental/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Fosfatasa Alcalina/metabolismo , Fósforo/análisis , Fósforo/metabolismo , Periodontitis/microbiología , Periodontitis/patología , Microscopía Electrónica de Transmisión , Femenino , Adulto , Calcio/metabolismo , Calcio/análisis , Masculino , Persona de Mediana Edad
12.
Front Pharmacol ; 15: 1396975, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38725666

RESUMEN

Osteosarcoma (OS) is the most common primary malignant bone tumor. In the clinic, usual strategies for OS treatment include surgery, chemotherapy, and radiation. However, all of these therapies have complications that cannot be ignored. Therefore, the search for better OS treatments is urgent. Black phosphorus (BP), a rising star of 2D inorganic nanoparticles, has shown excellent results in OS therapy due to its outstanding photothermal, photodynamic, biodegradable and biocompatible properties. This review aims to present current advances in the use of BP nanoparticles in OS therapy, including the synthesis of BP nanoparticles, properties of BP nanoparticles, types of BP nanoparticles, and modification strategies for BP nanoparticles. In addition, we have discussed comprehensively the application of BP in OS therapy, including single, dual, and multimodal synergistic OS therapies, as well as studies about bone regeneration and antibacterial properties. Finally, we have summarized the conclusions, limitations and perspectives of BP nanoparticles for OS therapy.

13.
RSC Adv ; 14(24): 16747-16757, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38784407

RESUMEN

One of the main obstacles to the development of sustainable biomass feedstocks today is the research of selective hydrogenation of biomass platform compounds for the synthesis of high-value chemicals. This work reports on the synthesis of a Ni/Fe bimetallic catalyst with nitrogen-doped carbon serving as the carrier, hydrogen serving as the primary donor, and isopropanol serving as the reaction medium and serving as a secondary donor. Vanillin was catalytically hydrogenated to produce 4-methylguaiacol, a complete hydrogenation product, under a reaction temperature of 200 °C for four hours. A single product with a good yield (95.26% conversion and selectivity up to 99%) was achieved by the moderate conditions, offering a potential route for the catalytic hydrogenation of biomass platform compounds.

14.
Sci Rep ; 14(1): 11581, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773247

RESUMEN

The (3 + 1)-dimensional Painlevé integrable equation are a class of nonlinear differential equations with special properties, which play an important role in nonlinear science and are of great significance in solving various practical problems, such as many important models in fields such as quantum mechanics, statistical physics, nonlinear optics, and celestial mechanics. In this work, we utilize the Hirota bilinear form and Mathematica software to formally obtain the interaction solution among lump wave, solitary wave and periodic wave, which has not yet appeared in other literature. Additionally, using the ( G ' / G ) -expansion method, we provide a rich set of exact solutions for the (3 + 1)-dimensional Painlevé integrable equation, which includes two functions with arbitrary values. This method is the first to be applied to the (3 + 1)-dimensional Painlevé integrable equation. By giving some 3D graphics and density maps, the dynamic properties are analyzed and demonstrated, which is beneficial for promoting understanding and application of the (3 + 1)-dimensional Painlevé integrable equation.

15.
Waste Manag ; 184: 92-100, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38805759

RESUMEN

The increasing application of municipal solid waste incineration (MSWI) emphasises the need for MSWI fly ash (FA) safe treatment. Based on the compositional complementarity of FA from grate furnaces (G-FA) and fluidised bed incinerators (F-FA), we proposed a co-reduction process to treat G-FA and F-FA together for producing vitrified slag and ferroalloys. The clean vitrified slag and Fe-Cr-Ni-Cu alloy were obtained with the mass ratios of 1:9 âˆ¼ 6:4 (G-FA:F-FA) at 1300℃, which is about 300℃ lower than the conventional G-FA vitrification. The metals Zn, Cd, and Pb were mostly volatilised into the flue gas for potential recovery from the secondary FA. The thermodynamic SiO2-Al2O3-CaO ternary system demonstrated that an optimal mass ratio of the two complementary FA types contributes to the system shifting to the low-temperature melting zone. The co-reduction process of G-FA and F-FA could be a promising option for FA beneficial reutilization with environmental advantages.


Asunto(s)
Ceniza del Carbón , Incineración , Residuos Sólidos , Vitrificación , Incineración/métodos , Ceniza del Carbón/química , Residuos Sólidos/análisis , Eliminación de Residuos/métodos
16.
Heliyon ; 10(7): e28893, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38596135

RESUMEN

Objective: Late-onset myasthenia gravis (LOMG) often has comorbidities, and its initial symptoms may be ignored or misdiagnosed as other diseases. There were few large surveys on LOMG. Our study aimed to summarize clinical characteristics of LOMG to improve the rate of correct MG diagnosis. Methods: A retrospective cohort study included 240 LOMG patients with onset age ≥65 years old who were treated at PLA General Hospital from January 1, 2003 to January 1, 2023. Results: The male to female ratio was 1:1.2 (P = 0.699). MGFA clinical classification: Class I 31.3%, Class IIa 12.9%, Class IIb 51.3%, Class IIIa 0.8%, Class IIIb 0.8%, Class IV 0.4%, Class V2.5%. The onset symptom was ptosis in 78.8% and diplopia was in 18.8%. Swallowing dysfunction in the stage of LOMG was in 41.7%. The incidence of thymoma in LOMG was 14.2%. 85.4% of patients antibodies against the muscle acetylcholine receptor (AChR) are detected. The overall incidence of supramaximal repetitive nerve stimulation (Jolly test) was 57.1%, among which the highest positive rate (50.7%) was in the facial nerve. Jolly test of Class IIb was tested in the highest positive rate and Class I was in the lowest one (χ2 = 7.023, P = 0.030). Conclusion: There was no significant difference in the incidence of LOMG between males and females. The clinical manifestations were mainly Class I and Class II, and severe MG was rare. The most common onset symptom was ptosis. The incidence of LOMG with thymoma was low. Supramaximal repetitive nerve stimulation (Jolly test) of the facial nerve was the easiest to detect and Jolly test of Class IIb was tested in the highest positive rate and Class I was in the lowest one.

17.
Ambio ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600245

RESUMEN

Protected areas are a key component of global conservation, and the world is aiming to increase protected areas to cover 30% of land and water through the 30 × 30 Initiative under the Post-2020 Global Biodiversity Framework. However, factors affecting their success or failure in regard to promoting mammal population recovery are not well studied, particularly using quantitative approaches comparing across diverse taxa, biomes, and countries. To better understand how protected areas contribute to mammalian recovery, we conducted an analysis of 2706 mammal populations both inside and outside of protected areas worldwide. We calculated the annual percent change of mammal populations within and outside of terrestrial protected areas and examined the relationship between the percent change and a suite of human and natural characteristics including biome, region, International Union for Conservation of Nature (IUCN) protected area category, IUCN Red List classification, and taxonomic order. Our results show that overall mammal populations inside and outside of protected areas are relatively stable. It appears that Threatened mammals are doing better inside of protected areas than outside, whereas the opposite is true for species of least concern and Near Threatened species. We also found significant population increases in protected areas classified as category III and significant population decreases in protected and unprotected areas throughout Oceania. Our results demonstrate that terrestrial protected areas can be an important approach for mammalian recovery and conservation.

18.
Chin J Integr Med ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38607612

RESUMEN

Oral squamous cell carcinoma (OSCC) is the most common malignant cancer of the head and neck, with high morbidity and mortality, ranking as the sixth most common cancer in the world. The treatment of OSCC is mainly radiotherapy, chemotherapy and surgery, however, the prognosis of patients is still poor and the recurrence rate is high. This paper reviews the range of effects of natural medicinal plant active ingredients (NMPAIs) on OSCC cancer, including the types of NMPAIs, anti-cancer mechanisms, involved signaling pathways, and clinical trials. The NMPAIs include terpenoids, phenols, flavonoids, glycosides, alkaloids, coumarins, and volatile oils. These active ingredients inhibit proliferation, induce apoptosis and autophagy, inhibit migration and invasion of OSCC cells, and regulate cancer immunity to exert anti-cancer effects. The mechanism involves signaling pathways such as mitogen-activated protein kinase, phosphatidylinositol 3 kinase/protein kinase B, nuclear factor kappa B, miR-22/WNT1/ß-catenin and Nrf2/Keap1. Clinically, NMPAIs can inhibit the growth of OSCC, and the combined drug is more effective. Natural medicinal plants are promising candidates for the treatment of OSCC.

19.
Bioresour Technol ; 402: 130729, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38657826

RESUMEN

Low efficiency of the cultivation process is a major obstacle in the commercial production of Haematococcus pluvialis. Germination of red, non-motile cells is an efficient strategy for rapid acquisition of zoospores. However, the regulatory mechanisms associated with germination remain unexplored. In the present study, it was confirmed that the mitochondrial alternative oxidase (AOX) pathway accelerates H. pluvialis cell germination, and the regulatory mechanisms were clarified. When the AOX pathway was inhibited, the transcriptomic and metabonomic data revealed a downregulation in respiratory carbon metabolism and nucleotide synthesis due to NADH accumulation. This observation suggested that AOX promoted the rapid consumption of NADH, which accelerated carbohydrate and lipid catabolism, thereby producing carbon skeletons for DNA replication through respiratory metabolism. Moreover, AOX could potentially enhance germination by disturbing the abscisic acid signaling pathway. These findings provide novel insights for developing industrial cultivation models based on red-cell-germination for achieving rapid proliferation of H. pluvialis.


Asunto(s)
Carbono , Mitocondrias , Proteínas Mitocondriales , Oxidación-Reducción , Oxidorreductasas , Proteínas de Plantas , Oxidorreductasas/metabolismo , Carbono/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Mitocondriales/metabolismo , Mitocondrias/metabolismo , Chlorophyta/metabolismo , Chlorophyceae/metabolismo , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , NAD/metabolismo , Respiración de la Célula/fisiología
20.
J Environ Manage ; 359: 120996, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38669885

RESUMEN

Enhalus acoroides, the largest seagrass species in terms of morphology, has been observed to be declining significantly. In an effort to restore seagrass meadows, we conducted a transplantion utilizing dislodged rhizome fragments of E. acoroides as the donor materials. The growth of transplanted seagrass was monitored over a period of three years, and the impact of seagrass recolonization on sedimentary environment was assessed through analysis of sediment microbial diversity. The transplanted plants displayed notable growth, resulting in the successful recolonization of experimental plots by seagrass. The 3-year data also revealed the following findings: 1) the new shoot recruitment rate (per year) (NSR) of transplanted seagrass was 2.33 in the first year, 1.36 in the second year, and 0.83 in the third year, indicating a rapid initial growth rate of E. acoroides that subsequently slowed down; 2) the numbers of shoots and aboveground biomass of transplanted seagrass had increased by 13.0 and 15.9-fold, respectively, whereas only 3.3 and 5.3-fold increases of the natural seagrass were observed, suggesting that the transplantation of seagrass leads to a significantly accelerated recovery compared to its natural regeneration process. Furthermore, the restoration of E. acoroides resulted in a higher microbial diversity in the submarine sediments within the restoration area, as compared to the adjacent unvegetated area. This suggests that the re-vegetation of E. acoroides has a positive influence on the overall health of the sedimentary environment. This study strongly advocates for the active transplantation of dislodged E. acoroides plants resulting from human activities as a potential approach for future coastal management, specifically for the restoration of E. acoroides meadows.


Asunto(s)
Sedimentos Geológicos , Rizoma , Sedimentos Geológicos/microbiología , Biodiversidad , Biomasa
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