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1.
J Pineal Res ; 76(5): e12987, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38975671

RESUMEN

Sleep deprivation (SD) has been associated with a plethora of severe pathophysiological syndromes, including gut damage, which recently has been elucidated as an outcome of the accumulation of reactive oxygen species (ROS). However, the spatiotemporal analysis conducted in this study has intriguingly shown that specific events cause harmful damage to the gut, particularly to goblet cells, before the accumulation of lethal ROS. Transcriptomic and metabolomic analyses have identified significant enrichment of metabolites related to ferroptosis in mice suffering from SD. Further analysis revealed that melatonin could rescue the ferroptotic damage in mice by suppressing lipid peroxidation associated with ALOX15 signaling. ALOX15 knockout protected the mice from the serious damage caused by SD-associated ferroptosis. These findings suggest that melatonin and ferroptosis could be targets to prevent devastating gut damage in animals exposed to SD. To sum up, this study is the first report that proposes a noncanonical modulation in SD-induced gut damage via ferroptosis with a clearly elucidated mechanism and highlights the active role of melatonin as a potential target to maximally sustain the state during SD.


Asunto(s)
Ferroptosis , Melatonina , Ratones Noqueados , Privación de Sueño , Animales , Ratones , Melatonina/metabolismo , Melatonina/farmacología , Privación de Sueño/metabolismo , Masculino , Especies Reactivas de Oxígeno/metabolismo , Ratones Endogámicos C57BL , Peroxidación de Lípido , Araquidonato 15-Lipooxigenasa/metabolismo , Araquidonato 15-Lipooxigenasa/genética , Araquidonato 12-Lipooxigenasa
2.
Appl Opt ; 63(12): 3343-3348, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38856486

RESUMEN

A denoising method applied to atmospheric coherent length lidar is proposed. Wavelet decomposition (WD) and the adaptive median filter (ADMF) are combined in this method. In this research, the effectiveness of the WD-ADMF has been verified through simulation and measurement. The results show that this filter algorithm, when applied to lidar data, improves the average peak signal-to-noise ratio (PSNR) and centroid error while maintaining data integrity such that the measurement of coherence length or the inference of C n2 from coherence length more closely matches simulated truth and measured data.

3.
J Environ Manage ; 359: 121055, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38701585

RESUMEN

Globally, forest soils are considered as important sources and sinks of greenhouse gases (GHGs). However, most studies on forest soil GHG fluxes are confined to the topsoils (above 20 cm soil depths), with only very limited information being available regarding these fluxes in the subsoils (below 20 cm soil depths), especially in managed forests. This limits deeper understanding of the relative contributions of different soil depths to GHG fluxes and global warming potential (GWP). Here, we used a concentration gradient-based method to comprehensively investigate the effects of thinning intensity (15% vs. 35%) and nutrient addition (no fertilizer vs. NPK fertilizers) on soil GHG fluxes from the 0-40 cm soil layers at 10 cm depth intervals in a Chinese fir (Cunninghamia lanceolata) plantation. Results showed that forest soils were the sources of CO2 and N2O, but the sinks of CH4. Soil GHG fluxes decreased with increasing soil depth, with the 0-20 cm soil layers identified as the dominant producers of CO2 and N2O and consumers of CH4. Thinning intensity did not significantly affect soil GHG fluxes. However, fertilization significantly increased CO2 and N2O emissions and CH4 uptake at 0-20 cm soil layers, but decreased them at 20-40 cm soil layers. This is because fertilization alleviated microbial N limitation and decreased water filled pore space (WFPS) in topsoils, while it increased WFPS in subsoils, ultimately suggesting that soil WFPS and N availability (especially NH4+-N) were the predominant regulators of GHG fluxes along soil profiles. Generally, there were positive interactive effects of thinning and fertilization on soil GHG fluxes. Moreover, the 35% thinning intensity without fertilization had the lowest GWP among all treatments. Overall, our results suggest that fertilization may not only cause depth-dependent effects on GHG fluxes within soil profiles, but also impede efforts to mitigate climate change by promoting GHG emissions in managed forest plantations.


Asunto(s)
Fertilizantes , Gases de Efecto Invernadero , Suelo , Gases de Efecto Invernadero/análisis , Suelo/química , Bosques , Metano/análisis , Dióxido de Carbono/análisis , Cunninghamia/crecimiento & desarrollo , Calentamiento Global , Óxido Nitroso/análisis , China
4.
Sensors (Basel) ; 23(13)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37447846

RESUMEN

In the process of the modulation recognition of underwater acoustic communication signals, the multipath effect seriously interferes with the signal characteristics, reducing modulation recognition accuracy. The existing methods passively improve the accuracy from the perspective of selecting appropriate signal features, lacking specialized preprocessing for suppressing multipath effects. So, the accuracy improvement of the designed modulation recognition models is limited, and the adaptability to environmental changes is poor. The method proposed in this paper actively utilizes common synchronous signals in underwater acoustic communication as detection signals to achieve passive time reversal without external signals and designs a passive time reversal-autoencoder to suppress multipath effects, enhance signals' features, and improve modulation recognition accuracy and environmental adaptability. Firstly, synchronous signals are identified and estimated. Subsequently, a passive time reversal-autoencoder is designed to enhance power spectrum and square spectrum features. Finally, a modulation classification is performed using a convolutional neural network. The model is trained in simulation channels generated by Bellhop and tested in actual channels which are different from the training period. The average recognition accuracy of the six modulated signals is improved by 10% compared to existing passive modulation recognition methods, indicating good environmental adaptability as well.


Asunto(s)
Acústica , Comunicación , Simulación por Computador , Redes Neurales de la Computación , Reconocimiento en Psicología
5.
J Asian Nat Prod Res ; 25(9): 834-841, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36617869

RESUMEN

A chemical investigation of 95% ethanol extract from the stem and branch of Tripterygium wilfordii has resulted in the isolation and characterization of two new compounds, one neolignan (1) and one phenylalanine derivative (2), as well as four known compounds (3-6). The structures of the new compounds were determined based on extensive spectroscopic analyses. The absolute configuration of compound 1 was defined by X-ray crystallographic analyses and electronic circular dichroism calculation. In addition, compounds 2 and 4-6 exhibited inhibitory effects against NO production in LPS-induced RAW 264.7 macrophages with the IC50 value ranging from 3.51 µM to 30.40 µM.


Asunto(s)
Óxido Nítrico , Tripterygium , Ratones , Animales , Células RAW 264.7 , Tripterygium/química , Hojas de la Planta/química , Macrófagos , Estructura Molecular
6.
J Asian Nat Prod Res ; 25(12): 1184-1190, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37178131

RESUMEN

Two new pregnane glycosides (1 and 2), together with four known ones (3- 6), were isolated from the roots of Cynanchum auriculatum Royle ex Wight (Asclepiadaceae). On the basis of detailed spectroscopic analysis and chemical method, the structures of new compounds were characterized to be metaplexigenin 3-O-ß-D-cymaropyranosyl- (1→4)-α-L-diginopyranosyl-(1→4)-ß-D-cymaropyranoside (1), metaplexigenin 3-O-α-L-diginopyranosyl-(1→4)-ß-D-cymaropyranoside (2). All the isolated compounds (1-6) were tested for their in vitro inhibitory activity against the growth of human colon cancer cell lines HCT-116. Compounds 5 and 6 showed significant cytoxicities with IC50 values of 43.58 µM and 52.21 µM.


Asunto(s)
Cynanchum , Humanos , Cynanchum/química , Raíces de Plantas/química , Pregnanos/farmacología , Pregnanos/química , Glicósidos/farmacología , Glicósidos/química , Estructura Molecular
7.
Int J Mol Sci ; 24(16)2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37628743

RESUMEN

Immunochromatographic assay (ICA) plays an important role in in vitro diagnostics because of its simpleness, convenience, fastness, sensitivity, accuracy, and low cost. The employment of magnetic nanoparticles (MNPs), possessing both excellent optical properties and magnetic separation functions, can effectively promote the performances of ICA. In this study, an ICA based on MNPs (MNP-ICA) has been successfully developed for the sensitive detection of carcinoembryonic antigen (CEA). The magnetic probes were prepared by covalently conjugating carboxylated MNPs with the specific monoclonal antibody against CEA, which were not only employed to enrich and extract CEA from serum samples under an external magnetic field but also used as a signal output with its inherent optical property. Under the optimal parameters, the limit of detection (LOD) for qualitative detection with naked eyes was 1.0 ng/mL, and the quantitative detection could be realized with the help of a portable optical reader, indicating that the ratio of optical signal intensity correlated well with CEA concentration ranging from 1.0 ng/mL to 64.0 ng/mL (R2 = 0.9997). Additionally, method comparison demonstrated that the magnetic probes were beneficial for sensitivity improvement due to the matrix effect reduction after magnetic separation, and the MNP-ICA is eight times higher sensitive than ICA based on colloidal gold nanoparticles. The developed MNP-ICA will provide sensitive, convenient, and efficient technical support for biomarkers rapid screening in cancer diagnosis and prognosis.


Asunto(s)
Antígeno Carcinoembrionario , Nanopartículas de Magnetita , Oro , Anticuerpos Monoclonales , Inmunoensayo
8.
Int J Mol Sci ; 23(17)2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36077387

RESUMEN

Carbohydrate antigen 199 (CA199) is a serum biomarker which has certain value and significance in the diagnosis, prognosis, treatment, and postoperative monitoring of cancer. In this study, a lateral flow immunoassay based on europium (III) polystyrene time-resolved fluorescence microspheres (TRFM-based LFIA), integrated with a portable fluorescence reader, has been successfully establish for rapid and quantitative analysis of CA199 in human serum. Briefly, time-resolved fluorescence microspheres (TRFMs) were conjugated with antibody I (Ab1) against CA199 as detection probes, and antibody II (Ab2) was coated as capture element, and a "TRFMs-Ab1-CA199-Ab2" sandwich format would form when CA199 was detected by the TRFM-based LFIA. Under the optimal parameters, the detection limit of the TRFM-based LFIA for visible quantitation with the help of an ultraviolet light was 4.125 U/mL, which was four times lower than that of LFIA based on gold nanoparticles. Additionally, the fluorescence ratio is well linearly correlated with the CA199 concentration (0.00-66.0 U/mL) and logarithmic concentration (66.0-264.0 U/mL) for quantitative detection. Serum samples from 10 healthy people and 10 liver cancer patients were tested to confirm the performances of the point-of-care application of the TRFM-based LFIA, 20.0 U/mL of CA199 in human serum was defined as the threshold for distinguishing healthy people from liver cancer patients with an accuracy of about 60%. The establishment of TRFM-based LFIA will provide a sensitive, convenient, and efficient technical support for rapid screening of CA199 in cancer diagnosis and prognosis.


Asunto(s)
Neoplasias Hepáticas , Nanopartículas del Metal , Biomarcadores de Tumor , Oro , Humanos , Inmunoensayo , Límite de Detección , Microesferas
9.
Small ; 17(41): e2102565, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34510747

RESUMEN

Hybrid supercapacitors (HSCs), also called supercapattery, which can substitute for low power density batteries have attracted extensive interest. However, when HSCs comes to commercial applications, there is still space for improvement in energy density. It seems that designing of electrode with high capacity is an effective measure. Herein, amorphous-crystalline MoO3 -Ni3 S2 /NF-0.5 nanosheet arrays are developed as battery-type electrodes. Specifically, the sheet-like structure of crystalline Ni3 S2 can achieve rich structural nanocrystallization, improving the redox reaction efficiency. Meanwhile, the disordered structure and irregular surface of the amorphous MoO3 are conducive to maximize the contact between the electrode and electrolyte, slowing down the volume change caused by the continuous charge-discharge process. As a result, it displays an ultrahigh areal specific capacity of 8.52 C cm-2 at 5 mA cm-2 , and superior lifespan up to 7500 cycles with 90.0% retention. Further, when assembled into HSCs, the specific capacity reaches 1.47 C cm-2 , corresponding to an energy density of 4.18 mWh cm-2 at a power density of 0.34 mW cm-2 . Totally, the design of the unique structure displays a valuable measure for rational development of high energy density hybrid energy storage devices that are not limited to supercapacitors.

10.
Small ; 16(31): e2000180, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32596998

RESUMEN

Skutterudite CoP3 holds a unique structural formation that exhibits much better electronic properties for obtaining high energy density supercapacitors. Herein, novel skutterudite Ni-CoP3 nanosheets are constructed by etching and coprecipitating at room temperature and subsequent low-temperature phosphorization reaction. Benefiting from the enhanced electrical conductivity and more electroactive sites brought about by adjusting the electronic structure with Ni incorporating the Ni-CoP3 electrode with a battery-type demonstrates an ultrahigh specific capacity of 0.7 mA h cm-2 and exceptional cycling stability. The asymmetric supercapacitor (ASC) device fabricated by employing Ni-CoP3 and activated carbon (AC) as positive and negative electrodes, resepectively, exhibits a remarkable high energy density of 89.6 Wh kg-1 at 796 W kg-1 and excellent stability of 93% after 10 000 cycles, due to the skutterudite structure. The skutterudite Ni-CoP3 shows a great potential to be an excellent next-generation electrode candidate for supercapacitors and other energy storage devices.

11.
New Phytol ; 227(3): 757-765, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32215914

RESUMEN

Litter decomposition plays a key role in nutrient cycling across ecosystems, yet to date, we lack a comprehensive understanding of the nonadditive decomposition effects in leaf litter mixing experiments. To fill that gap, we compiled 69 individual studies with the aim to perform two meta-analyses on nonadditive effects. We show that a significant synergistic effect (faster decomposition in mixtures than expected) occurs at a global scale, with an average increase of 3-5% in litter mixtures. In particular, low-quality litter in mixtures shows a significant synergistic effect, while additive effects are observed for high-quality species. Additionally, synergistic effects turn into antagonistic effects when soil fauna are absent or litter is in very late stages of decomposition (near-humus). In contrast to temperate and tropical areas, studies in boreal regions show significant antagonistic effects. Our two meta-analyses provide a systematic evaluation of nonadditive effects in mixed litter decomposition studies and show that litter quality alters the effects of litter mixing. Our results indicate that nutrient transfer, soil fauna and inhibitory secondary compounds can influence mixing effects. We also highlight that synergistic and antagonistic effects occur concurrently, and the final litter mixing effect results from the interplay between them.


Asunto(s)
Ecosistema , Suelo , Hojas de la Planta
12.
Molecules ; 23(10)2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-30308969

RESUMEN

Three new meliacarpinin-type limonoids, toosendanes A⁻C (1⁻3), along with three, known meliacarpinins (4⁻6) were isolated from the bark of Melia toosendan. Their structures, along with their absolute configurations, were elucidated, based on detailed analyses. These included HRESIMS and 1D/2D-NMR, modified Mosher's method, and electronic circular dichroism (ECD). Limonoids 2 and 3 showed moderate inhibitory activity on LPS-activated, RAW 264.7 macrophages.


Asunto(s)
Limoninas/aislamiento & purificación , Melia/química , Corteza de la Planta/química , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Espectroscopía de Resonancia Magnética con Carbono-13 , Limoninas/química , Limoninas/farmacología , Ratones , Espectroscopía de Protones por Resonancia Magnética , Células RAW 264.7
13.
Mediators Inflamm ; 2017: 3090782, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28839348

RESUMEN

IL-18 has been found to be associated with eczema. However, little is known of the role of IL-18 binding protein (BP) and IL-18 receptor (R) in eczema. We therefore investigated the expression of IL-18, IL-18BP, and IL-18R on mast cells by using flow cytometry analysis and mouse eczema model. The results showed that plasma free IL-18 and free IL-18BP levels in eczema patients were higher than those in healthy controls. IL-18 provoked up to 3.1-fold increase in skin mast cells. IL-18 induced also an increase in IL-18BP+ mast cells, but a reduction of IL-18R+ mast cells in mouse eczema skin. It was found that house dust mite allergen Der p1 and egg allergen OVA induced upregulation of the expression of IL-18, IL-18BP, and IL-18R mRNAs in HMC-1 cells following 2 and 16 h incubation. In conclusion, correlation of IL-18 and IL-18BP in eczema plasma suggests an important balance between IL-18 and IL-18BP in eczema. The decrease in molar concentration ratio of plasma IL-18BP/IL-18 and allergen-induced upregulated expression of IL-18 and IL-18R in skin mast cells of the patients with eczema suggests that anti-IL-18 including IL-18BP therapy may be useful for the treatment of eczema.


Asunto(s)
Eccema/sangre , Eccema/inmunología , Péptidos y Proteínas de Señalización Intercelular/sangre , Interleucina-18/sangre , Mastocitos/metabolismo , Receptores de Interleucina-18/sangre , Adulto , Alérgenos/inmunología , Animales , Hipersensibilidad al Huevo/inmunología , Femenino , Humanos , Masculino , Ratones Endogámicos BALB C , Persona de Mediana Edad , Adulto Joven
14.
Nat Prod Res ; : 1-8, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38629167

RESUMEN

Tripterygium wilfordii has been historically employed as a conventional botanical insecticide and a plant of medicinal significance. A new dihydroagarofuran sesquiterpene (1) and a new acyclic compound (2), along with seven known compounds (3-9), have been isolated from the aerial parts of Tripterygium wilfordii. The identification of the structures of novel compounds were accomplished through comprehensive spectroscopic analyses, encompassing HRESIMS, NMR, UV, IR, and a comparative analysis with spectroscopic data from compounds previously characterised. In in-vitro bioassay, compound 8 exhibited significant inhibitory activity for NO release in LPS-induced RAW 264.7 cells, with an IC50 value of 15.7 µM.

15.
Chin J Nat Med ; 21(3): 233-240, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37003645

RESUMEN

The stem and branch extract of Tripterygium wilfordii (Celastraceae) afforded seven new dihydroagarofuran sesquiterpene polyesters [tripterysines A-G (1-7)] and eight known ones (8-15). The chemical structures of these new compounds were established based on combinational analysis of HR-ESI-MS and NMR techniques. The absolute configurations of tripterysines A-C (1-3) and E-G (5-7) were determined by X-ray crystallographic analysis and circular dichroism spectra. All the compounds were screened for their inhibitory effect on inflammation through determining their inhibitory effect on nitric oxide production in LPS-induced RAW 264.7 cells and the secretion of inflammatory cytokines TNF-α and IL-6 in LPS-induced BV2 macrophages. Compound 9 exhibited significant inhibitory activity on NO production with an IC50 value of 8.77 µmol·L-1. Moreover, compound 7 showed the strongest inhibitory effect with the secretion of IL-6 at 27.36%.


Asunto(s)
Sesquiterpenos , Tripterygium , Tripterygium/química , Ésteres/farmacología , Interleucina-6 , Lipopolisacáridos/farmacología , Hojas de la Planta/química , Antiinflamatorios/farmacología , Antiinflamatorios/química , Óxido Nítrico/análisis , Sesquiterpenos/farmacología , Sesquiterpenos/química , Estructura Molecular
16.
Nat Prod Res ; : 1-8, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36752387

RESUMEN

Two new aryltetralin-type lignans (1-2) were isolated from the dichloromethane fraction of 95% ethanol extract of Camellia oleifera fruit husk. Their structures were elucidated on the basis of spectroscopic analysis, and the absolute configurations of compounds 1-2 were determined by the comparison of measured ECD curves with the quantum chemical calculated ones. The new compounds were tested for their antioxidant activities and cytotoxicity against three human cancer cell lines (Huh-7, H460 and MCF-7). While compounds 1 and 2 only showed slight DPPH radical scavenging activities with the IC50 values of 38.68 ± 5.02 and 56.62 ± 1.49 µM, respectively.

17.
Huan Jing Ke Xue ; 44(7): 4201-4210, 2023 Jul 08.
Artículo en Zh | MEDLINE | ID: mdl-37438317

RESUMEN

Charcoal is a carbonaceous particulate matter with a highly aromatic structure produced by incomplete combustion, and it can cause persistent long-term effects on soil ecological functions. In this study, we determined soil organic carbon pools and associated enzyme activities following five years of different charcoal treatments[charcoal removal (B0), charcoal retained in situ (B1), and the addition of charcoal removed from B0(B2)] and the unburnt control (UB) in a recently harvested Pinus massoniana plantation subjected to broadcast burning. The results showed that dissolved organic carbon (DOC), microbial biomass carbon (MBC), coarse and fine particulate organic carbon (CPOC and FPOC), and recalcitrant carbon (RC) contents were significantly lower in B1 than those in UB soil (P<0.05). The MBC and FPOC contents of B2 soil were comparable to those of UB soil, which were significantly higher than those of B0 soil (P<0.001). There was no difference in MBC/TC between the B2 and UB soils, whereas MBC/TC was significantly lower in B0 than in UB soil (P<0.05). ß-glucosidase and peroxidase activities of B0, B1, and B2 soils were significantly lower than that of UB soil (P<0.01), and polyphenol oxidase activity was significantly lower in B0 and B2 soils than in UB soil (P<0.01). No significant difference in soil TC, DOC, readily oxidized carbon (ROC), CPOC, and RC content as well as associated enzyme activities was observed among the charcoal treatments (P>0.05). Redundancy analysis showed that sucrose and polyphenol oxidase were the key drivers influencing soil organic carbon fractions, accounting for 16.3% and 12.7% of the total variance, respectively. Overall, our findings indicated that fire-deposited charcoal played a positive role in enhancing soil microbial biomass carbon recovery, soil organic carbon accumulation, and stability, highlighting the importance of charcoal in the management of subtropical plantations in the future.


Asunto(s)
Carbono , Pinus , Carbón Orgánico , Suelo , Catecol Oxidasa , Materia Orgánica Disuelta
18.
Emerg Microbes Infect ; 12(1): 2149352, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36395069

RESUMEN

Coxsackievirus A16 (CA16), a main causative agent of hand, foot, and mouth disease (HFMD), has become a serious public health concern in the Asia-Pacific region. Here, we generated an anti-CA16 monoclonal antibody, DMA2017, derived from an epidemic strain CA16. Surprisingly, although DMA2017 could not neutralize the original and circulating CA16 strains in vitro, the passive transfer of DMA2017 (10 µg/g) could protect suckling mice from a lethal challenge with CA16 in vivo. Then, we confirmed the protective effect of DMA2017 relies on the Fc-dependent effector functions, such as antibody-dependent cellular cytotoxicity (ADCC). The linear epitope of DMA2017 was mapped by phage display technique to a conserved patch spanning residues 143-148 (NSHPPY) of the VP2 EF-loop of CA16. DMA2017 could inhibit the binding of the antibodies present in the sera of naturally infected children to CA16, indicating that the epitope of DMA2017 is immunodominant for CA16. Our results confirm, for the first time, that a potential preventive and therapeutic effect could be mediated by a non-neutralizing antibody elicited against CA16. These findings bring a hitherto understudied protective role of non-neutralizing antibodies during viral infections into the spotlight and provide a new perspective on the design and evaluation of CA16 vaccines.


Asunto(s)
Enterovirus Humano A , Enterovirus , Enfermedad de Boca, Mano y Pie , Vacunas Virales , Animales , Ratones , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Enfermedad de Boca, Mano y Pie/prevención & control , Epítopos , Anticuerpos Monoclonales
19.
Chem Biol Drug Des ; 102(6): 1643-1657, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37705131

RESUMEN

Ursolic acid (UA) is a pentacyclic triterpenoid, which exhibits many biological activities, particularly in anti-cardiovascular and anti-diabetes. The further application of UA is greatly limited due to its low bioavailability and poor water solubility. Up to date, various UA derivatives have been designed to overcome these shortcomings. In this paper, the authors reviewed the development of UA derivatives as the anti-diabetes anti-cardiovascular reagents.


Asunto(s)
Triterpenos , Solubilidad , Triterpenos/farmacología , Triterpenos/uso terapéutico , Ácido Ursólico
20.
Front Plant Sci ; 14: 1139945, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37035087

RESUMEN

Introduction: Nutrient resorption is a key mechanism to conserve nutrients and overcome nutrient limitation in perennial plants. As an important afforested tree species in subtropical regions, Pinus massoniana grows well in nutrient-poor environments, however, the age-related pattern of nutrient acquisition strategy and the underlying mechanisms in P. massoniana plantations remain unclear. Methods: In this study, concentrations of nitrogen (N) and phosphorus (P) were measured in green and senesced needles, roots and soil samples collected from P. massoniana plantations with different stand ages (9-, 17-, 26-, 34- and 43-year-old) in south China. From these samples, nutrient resorption efficiency (RE) and stoichiometry were calculated. Results: Needle PRE significantly decreased with stand age, while there was no clear pattern of NRE along the stand development. Green needle N:P in older stands was significantly lower than in younger ones. Senesced needle C:P and N:P significantly decreased with stand age. Root and soil available P concentrations were significantly higher in older stands than in younger ones, and PRE was negatively correlated with soil available P concentration. Discussion: There was a shift from "conservative consumption" to "resource spending" P-use strategy, and P limitation decreased with stand development of P. massoniana plantations. The results provide information of changes in nutrients dynamics, which is relevant for the sustainable management of subtropical forest plantations.

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