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1.
Exp Physiol ; 109(1): 135-147, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-36951012

RESUMEN

By translating mechanical forces into molecular signals, proprioceptive neurons provide the CNS with information on muscle length and tension, which is necessary to control posture and movement. However, the identities of the molecular players that mediate proprioceptive sensing are largely unknown. Here, we confirm the expression of the mechanosensitive ion channel ASIC2 in proprioceptive sensory neurons. By combining in vivo proprioception-related functional tests with ex vivo electrophysiological analyses of muscle spindles, we showed that mice lacking Asic2 display impairments in muscle spindle responses to stretch and motor coordination tasks. Finally, analysis of skeletons of Asic2 loss-of-function mice revealed a specific effect on spinal alignment. Overall, we identify ASIC2 as a key component in proprioceptive sensing and a regulator of spine alignment.


Asunto(s)
Canales Iónicos Sensibles al Ácido , Propiocepción , Animales , Ratones , Canales Iónicos Sensibles al Ácido/metabolismo , Husos Musculares/fisiología , Propiocepción/fisiología , Células Receptoras Sensoriales/metabolismo
2.
Clin Proteomics ; 20(1): 24, 2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37355563

RESUMEN

BACKGROUND: Immune thrombocytopenia (ITP) is a common autoimmune disease characterized by loss of immune tolerance to platelet autoantigens leading to excessive destruction and insufficient production of platelets. METHOD: Quantitative liquid chromatography tandem mass spectrometry (LC-MS/MS) was performed to detect the differentially expressed proteins in bone marrow samples from active ITP patients and normal controls. RESULT: Our bioinformatic analysis identified two upregulated proteins (ORM1 and vWF) and two downregulated proteins (PPBP and SPARC) related to immune function. The four proteins were all found to be related to the tumor necrosis factor (TNF) -α signalling pathway and involved in the pathogenesis of ITP in KEGG pathway analysis. CONCLUSION: Bioinformatics analysis identified differentially expressed proteins in bone marrow that are involved in the TNF-α signalling pathway and are related to the activation of immune function in ITP patients. These findings could provide new ideas for research on the loss of immune tolerance in ITP patients.

3.
Clin Lab ; 68(11)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36377989

RESUMEN

BACKGROUND: Metastatic or recurrent endometrial cancers with low survival rate had no standard or limited therapy choice. The aim of our study was to determine the efficiency and safety of tislelizumab combined with carboplatin-paclitaxel as a front-line therapy for patients with metastatic or recurrent endometrial cancer. METHODS: This clinical retrospective cohort study examined 24 Chinese patients with metastasis or recurrence but had not yet received treatment. The therapeutic regimen consisted of 6 cycles of intravenous paclitaxel (175 mg/m2) and carboplatin (target AUC: 5 mg/mL/min) with tislelizumab (200 mg) once every 3 weeks, and then intravenous tislelizumab (200 mg) once every 3 weeks until disease progression or unacceptable toxicity. RESULTS: At the 18-month follow-up, 8 patients were still receiving treatment, 13 were dead, and 3 withdrew. The objective response rate (ORR) was 62.5%, the disease control rate was 75.00%. The ORR was 77.78% for patients positive for PD-L1 and 69.23% for patients positive for MSI-H. The median overall survival time was 11.50 months, and the median progression-free survival time was 6.00 months. Half of the patients experienced 3 - 4 grade adverse events. There were no allergic reactions or treatment-related deaths. CONCLUSIONS: Tislelizumab combined with carboplatin-paclitaxel was used as a front-line therapy, had a beneficial effect and was safe for patients with metastatic or recurrent endometrial cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Endometriales , Femenino , Humanos , Carboplatino/uso terapéutico , Estudios Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/inducido químicamente , Paclitaxel/uso terapéutico , Paclitaxel/efectos adversos , Neoplasias Endometriales/tratamiento farmacológico
4.
Angew Chem Int Ed Engl ; 60(2): 990-997, 2021 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-32969140

RESUMEN

Zinc ion hybrid capacitors (ZIHCs) are promising energy storage devices for emerging flexible electronics, but they still suffer from trade-off in energy density and cycling life. Herein, we show that such a dilemma can be well-addressed by deploying ZnCl2 based electrolytes. Combining experimental studies and density functional theory (DFT) calculations, for the first time, we demonstrate an intriguing chloride ion (Cl- ) facilitated desolvation mechanism in hydrated [ZnCl]+ (H2 O)n-1 (with n=1-6) clusters. Based on this mechanism, a water-in-salt type hydrogel electrolyte filled with ZnCl2 was developed to concurrently improve the energy storage capacity of porous carbon materials and the reversibility of Zn metal electrode. The resulting ZIHCs deliver a battery-level energy density up to 217 Wh kg-1 at a power density of 450 W kg-1 , an unprecedented cycling life of 100 000 cycles, together with excellent low-temperature adaptability and mechanical flexibility.

5.
Biochem Biophys Res Commun ; 522(1): 233-239, 2020 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-31757426

RESUMEN

Iron (Fe) is a major micronutrient which influences plant growth, development, quality and yield. Although basic helix-loop-helix (bHLH) transcription factors (TFs) which respond to iron deficiency have been identified, the molecular mechanisms have not been fully elucidated. In this study, a novel bHLH TF, NtbHLH1, was found to be induced by iron deficiency. Further analysis indicated that NtbHLH1 is localized to the nucleus and functions as a transcriptional activator. Moreover, overexpression of NtbHLH1 resulted in longer roots, altered rhizosphere pH and increased ferric-chelate reductase activity in iron deficient conditions. Overall these changes resulted in increased iron uptake relative to wild type plants. NtbHLH1 mutants, on the other hand, had an opposite phenotype. In addition, transcript levels of seven genes associated with iron deficiency response were higher in the NtbHLH1 overexpression transgenic plants and lower in ntbhlh1 relative to the WT under iron deficiency treatment. Taken together, these results demonstrated that NtbHLH1 plays a key role in iron deficiency response and they provide new insights into the molecular basis of iron homeostasis in tobacco.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Regulación de la Expresión Génica de las Plantas , Hierro/metabolismo , Nicotiana/metabolismo , Proteínas de Plantas/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Homeostasis , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Nicotiana/genética , Regulación hacia Arriba
6.
Small ; 16(50): e2003400, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33217172

RESUMEN

2D materials have shown high potentials for fabricating next-generation membranes. To date, extensive studies have focused on the applications of 2D material membranes in gas and aqueous media. Recently, compelling opportunities emerge for 2D material membranes in separation applications in organic solvents because of their unique properties, such as ultrathin mono- to few-layers, outstanding chemical resistance toward organic solvents. Hence, this review aims to provide a timely overview of the current state-of-the-art of 2D material membranes focusing on their applications in organic solvent separations. 2D material membranes fabricated using graphene materials and a few representative nongraphene-based 2D materials, including covalent organic frameworks and MXenes, are summarized. The key membrane design strategies and their effects on separation performances in organic solvents are also examined. Last, several perspectives are provided in terms of the critical challenges for 2D material membranes, including standardization of membrane performance evaluation, improving understandings of separation mechanisms, managing the trade-off of permeability and selectivity, issues related to application versatility, long-term stability, and fabrication scalability. This review will provide a useful guide for researchers in creating novel 2D material membranes for advancing new separation techniques in organic solvents.

7.
New Phytol ; 221(1): 470-481, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30078224

RESUMEN

Despite their ubiquitous distribution and significant ecological roles, soil microorganisms have long been neglected in investigations addressing parasitic plant-host interactions. Because nutrient deprivation is a primary cause of host damage by parasitic plants, we hypothesized that beneficial soil microorganisms conferring nutrient benefits to parasitized hosts may play important roles in alleviating damage. We conducted a pot cultivation experiment to test the inoculation effect of an arbuscular mycorrhizal fungus (Glomus mosseae), a rhizobium (Rhizobium leguminosarum) and their interactive effects, on alleviation of damage to a legume host (Trifolium repens) by two root hemiparasitic plants with different nutrient requirements (N-demanding Pedicularis rex and P-demanding P. tricolor). Strong interactive effects between inoculation regimes and hemiparasite identity were observed. The relative benefits of microbial inoculation were related to hemiparasite nutrient requirements. Dual inoculation with the rhizobium strongly enhanced promotional arbuscular mycorrhizal effects on hosts parasitized by P. rex, but reduced the arbuscular mycorrhizal promotion on hosts parasitized by P. tricolor. Our results demonstrate substantial contribution of arbuscular mycorrhizal and rhizobial symbioses to alleviating damage to the legume host by root hemiparasites, and suggest that soil microorganisms are critical factors regulating host-parasite interactions and should be taken into account in future studies.


Asunto(s)
Interacciones Huésped-Parásitos/fisiología , Micorrizas/fisiología , Pedicularis/fisiología , Rhizobium leguminosarum/fisiología , Trifolium/microbiología , Trifolium/parasitología , Inoculantes Agrícolas , Glomeromycota/fisiología , Nitrógeno/metabolismo , Fósforo/metabolismo , Nodulación de la Raíz de la Planta/fisiología , Raíces de Plantas/microbiología , Raíces de Plantas/parasitología , Brotes de la Planta/química , Brotes de la Planta/metabolismo , Simbiosis/fisiología , Trifolium/fisiología
8.
Environ Sci Technol ; 53(17): 10236-10245, 2019 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-31361474

RESUMEN

The effect of photochemical reaction time on glyoxal and hydrogen peroxide at the air-liquid (a-l) interface is investigated using in situ time-of-flight secondary ion mass spectrometry (ToF-SIMS) enabled by a system for analysis at the liquid vacuum interface (SALVI) microreactor. Carboxylic acids are formed mainly by reaction with hydroxyl radicals in the initial reactions. Oligomers, cluster ions, and water clusters formed due to longer photochemistry. Our results provide direct molecular evidence that water clusters are associated with proton transfer and the formation of oligomers and cluster ions at the a-l interface. The oligomer formation is facilitated by water cluster and cluster ion formation over time. Formation of higher m/z oligomers and cluster ions indicates the possibility of highly oxygenated organic components formation at the a-l interface. Furthermore, new chemical reaction pathways, such as surface organic cluster, hydration shell, and water cluster formation, are proposed based on SIMS spectral observations, and the existing understanding of glyoxal photochemistry is expanded. Our in situ findings verify that the a-l interfacial reactions are important pathways for aqueous secondary organic aerosol (aqSOA) formation.


Asunto(s)
Glioxal , Radical Hidroxilo , Aerosoles , Fotoquímica , Agua
9.
Small ; : e1800582, 2018 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-29882370

RESUMEN

Compactness and versatility of fiber-based micro-supercapacitors (FMSCs) make them promising for emerging wearable electronic devices as energy storage solutions. But, increasing the energy storage capacity of microscale fiber electrodes, while retaining their high power density, remains a significant challenge. Here, this issue is addressed by incorporating ultrahigh mass loading of ruthenium oxide (RuO2 ) nanoparticles (up to 42.5 wt%) uniformly on nanocarbon-based microfibers composed largely of holey reduced graphene oxide (HrGO) with a lower amount of single-walled carbon nanotubes as nanospacers. This facile approach involes (1) space-confined hydrothermal assembly of highly porous but 3D interconnected carbon structure, (2) impregnating wet carbon structures with aqueous Ru3+ ions, and (3) anchoring RuO2 nanoparticles on HrGO surfaces. Solid-state FMSCs assembled using those fibers demonstrate a specific volumetric capacitance of 199 F cm-3 at 2 mV s-1 . Fabricated FMSCs also deliver an ultrahigh energy density of 27.3 mWh cm-3 , the highest among those reported for FMSCs to date. Furthermore, integrating 20 pieces of FMSCs with two commercial flexible solar cells as a self-powering energy system, a light-emitting diode panel can be lit up stably. The current work highlights the excellent potential of nano-RuO2 -decorated HrGO composite fibers for constructing micro-supercapacitors with high energy density for wearable electronic devices.

10.
J Environ Sci (China) ; 71: 2-12, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30195679

RESUMEN

To investigate the fog chemistry along the Yangtze River basin, a field observation experiment was performed from Shanghai to Wuhan during November 2015. Fifteen fog water samples were collected by using a three-stage Caltech Active Strand Cloud water Collector (CASCC). The three-stage CASCC was mounted on the board of a ship. PH, electrical conductivity (EC), H2O2, HCHO, S(IV), ten inorganic ions, seven organicacids and sixteen trace metal elements were measured in this study. The pH of fog water samples ranged from weakly acidic (pH4.3) to weakly alkaline (pH7.05) and the EC ranged from 32.4 to 436.3µS/cm. The main cations in fog water were NH4+ and Ca2+, accounting for 12.35% and 29.07% of those inorganic ions, respectively. In addition, SO42- and NO3- contributed to 25.52% and 12.93% to total anion concentrations respectively. Moreover, the dominant kinds of organicacids were formate and oxalate, occupying 45.28% and 28.03% of the total organicacids, respectively. For trace metal elements in fog samples, Al, Fe, Zn, and Ba revealed 34.6%, 16.4%, 19.3%, and 20.9% contributions to these sixteen trace element concentrations, respectively. The results indicated that pollutants were mainly from human activities, including fossil fuel combustion, biomass burning, steel-making, stone quarrying and sand digging. Besides, natural sources including natural background levels and long-range transport of sea salt particles also aggravated the pollution levels in the fog events along the Yangtze River.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Tiempo (Meteorología) , China , Vapor/análisis
11.
Phys Chem Chem Phys ; 19(31): 20357-20366, 2017 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-28597894

RESUMEN

Aqueous surfaces after photochemical and dark reactions of glyoxal and hydrogen peroxide (H2O2) have been studied using a microfluidic reactor coupled with an in situ liquid time-of-flight secondary ion mass spectrometry (ToF-SIMS) for the first time. Spectral principal component analysis was used to determine similarities and differences among various photochemical aging and dark reaction samples and controls. Compared with previous results using bulk solutions, our unique liquid surface molecular imaging approach provided observations of glyoxal hydration (i.e., first and secondary products), oxidation products (i.e., glyoxylic acid, oxalic acid, formic acid, tartaric acid), oligomers, cluster ions, and water clusters with sub-micrometer spatial resolution. Observations of oxidation products give the physical foundation to deduce new reaction pathways at the aqueous surface. The first chemical mapping of water cluster changes between dark and photochemical aging suggests that glyoxal oxidation affects the hydrophobicity and water microenvironment at the surface, influencing the particle's ability of reactive uptake and subsequent cloud condensation nucleation and/or ice nucleation activation. Moreover, SIMS three-dimensional chemical mapping has made it possible to visualize the surface mixing state for the first time. We potentially provide a new method to investigate complex surface chemistry as an important source of aqueous secondary organic aerosol (aqSOA) formation in atmospheric chemistry.

12.
Phys Chem Chem Phys ; 19(34): 22627-22632, 2017 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-28664967

RESUMEN

Switchable ionic liquids (SWILs) derived from organic bases and alcohols are attractive due to their applications in gas capture, separations, and nanomaterial synthesis. However, their exact solvent structure still remains a mystery. We present the first chemical mapping of a SWIL solvent structure using in situ time-of-flight secondary ion mass spectrometry. In situ chemical mapping discovers two coexisting liquid phases and molecular structures vastly different from conventional ionic liquids. SWIL chemical speciation is found to be more complex than the known stoichiometry. Dimers and ionic clusters have been identified in SIMS spectra; and confirmed to be the chemical species differentiating from non-ionic liquids via spectral principal component analysis. Our unique in situ molecular imaging has advanced the understanding of SWIL chemistry and how this "heterogeneous" liquid structure may impact SWILs' physical and thermodynamic properties and associated applications.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2318-24, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30036021

RESUMEN

This article focused on the assessment of the potential of Raman spectroscopy for the determination of structural changes in black-bean protein isolate (BBPI) dispersions with low-frequency (20 kHz) ultrasonication applied at various powers (150, 300 or 450 W) and for different durations (12 or 24 min). It also reported on differential scanning calorimetry analyses. A decrease in TD at low- and medium-power ultrasonication confirmed these ultrasonication treatment disrupted internal hydrophobic interactions of protein molecules and broke up unstable aggregates to smaller soluble protein aggregates, while an increase in TD at high-power was attributed to repolymerization of aggregates. Raman spectroscopy analysis revealed a decrease in the α-helix proportion and an increase in ß-sheets after ultrasonic treatment except Sample E (300 W, 24 min). Transformation of aggregation results in a reconstruction in secondary structure of BBPI, especially in ß-sheet structure. Ultrasonic-treatment induced a decrease in the normalized intensity of the Raman band near 760 cm-1 which indicated that Tryptophan residues tended to expose and also indicated protein partially unfolding. No significant difference was found in Tyr doublet ratios between unheated and ultrasound-treated BBPI indicated that ultrasound did not change the microenvironment around tyrosyl residues. While the intensity of 1 450 cm-1 band increased with increasing ultrasonic intensity and treatment time, and then decreased with further increase in power and treatment time. In general, the formation of aggregation transferred g-g-t conformation to t-g-t conformation. Though some mechanism of aggregation-repolymerization of BBPI remains to be clearly defined, Raman spectroscopy provide a feasible tool to study the structural changes of BBPI prepared under different ultrasonic conditions, give a new perspective to elucidation of protein structure.

14.
J Plant Res ; 128(4): 563-72, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25956077

RESUMEN

Root hemiparasitic plants show optimal growth when attached to a suitable host by abstracting water and nutrients. Despite the fact that damage to host plants in the wild occurs frequently in various forms (e.g. grazing), effects of host damage on growth and physiological performance of root hemiparasites remain unclear. In this study, host shoot clipping was conducted to determine the influence of host damage on photosynthetic and growth performance of a weedy root hemiparasite, Pedicularis kansuensis, and its interaction with a host, Elymus nutans. Photosynthetic capacity, tissue mineral nutrient content and plant biomass of P. kansuensis were significantly improved when attached to a host plant. Host clipping had no effect on quantum efficiency (ΦPSII), but significantly reduced the growth rate and biomass of P. kansuensis. In contrast, clipping significantly improved photosynthetic capacity and accumulation of potassium in E. nutans. No significant decrease in biomass was observed in clipped host plants. By changing nutrient absorption and allocation, clipping affected the interaction between P. kansuensis and its host. Our results showed that host clipping significantly suppressed the growth of weedy P. kansuensis, but did not affect biomass accumulation in E. nutans. We propose that grazing (a dominant way of causing host damage in the field) may have a potential in the control against the weedy hemiparasite.


Asunto(s)
Elymus/parasitología , Pedicularis/fisiología , Brotes de la Planta/fisiología , Control de Malezas/métodos , Clorofila/química , Fluorescencia , Fotosíntesis , Malezas/crecimiento & desarrollo
15.
J Sci Food Agric ; 95(5): 1016-23, 2015 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-24931827

RESUMEN

BACKGROUND: Supercritical carbon dioxide (SC-CO2 ) has been shown to have a good pasteurising effect on food. However, very few research papers have investigated the possibility to exploit this treatment for solid foods, particularly for seafood. Considering the microbial safety of raw seafood consumption, the study aimed to explore the feasibility of microbial inactivation of shrimp (Metapenaeus ensis) and conch (Rapana venosa) by SC-CO2 treatment. RESULTS: Response surface methodology (RSM) models were established to predict and analyse the SC-CO2 process. A 3.69-log reduction in the total aerobic plate count (TPC) of shrimp was observed by SC-CO2 treatment at 53°C, 15 MPa for 40 min, and the logarithmic reduction in TPC of conch was 3.31 at 55°C, 14 MPa for 42 min. Sensory scores of the products achieved approximately 8 (desirable). The optimal parameters for microbial inactivation of shrimp and conch by SC-CO2 might be 55°C, 15 MPa and 40 min. CONCLUSION: SC-CO2 exerted a strong bactericidal effect on the TPC of shrimp and conch, and the products maintained good organoleptic properties. This study verified the feasibility of microbial inactivation of shrimp and conch by SC-CO2 treatment.


Asunto(s)
Dióxido de Carbono/química , Conservación de Alimentos , Gastrópodos/microbiología , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/crecimiento & desarrollo , Penaeidae/microbiología , Mariscos/microbiología , Animales , China , Recuento de Colonia Microbiana , Estudios de Factibilidad , Conservación de Alimentos/instrumentación , Alimentos Congelados/análisis , Alimentos Congelados/microbiología , Gastrópodos/química , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Calor , Humanos , Viabilidad Microbiana , Penaeidae/química , Transición de Fase , Presión , Sensación , Mariscos/análisis , Mariscos/economía , Estadística como Asunto , Factores de Tiempo
16.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 37(5): 508-13, 2015 Oct.
Artículo en Zh | MEDLINE | ID: mdl-26564500

RESUMEN

OBJECTIVE: To investigate whether sodium valproate (VPA) directly regulates the activity of Ankyrin G(AnkG) promoter in vitro. METHODS: The mouse AnkG promoter sequence was identified by comparing both human and mouse AnkG promoter sequences. The promoter was amplified from C57BL/6 mouse genome DNA and cloned into pGL3 Luciferase reporter vector. The Luciferase activity was detected in N2a and 293T cells and then treated with 0,0.5, and 1 mmol/L VPA for 12 h. The transcription activity of AnkG promoter in cells and the activity of VPA-treated Luciferase reporter vector in cells were detected using dual Luciferase reporter assay. RESULTS: The AnkG promoter clone and its expression vector were successfully established, as confirmed by enzyme digestion and sequencing. The AnkG promoter showed high transcription activity in both N2a and 293T cells. The Luciferase activity was significantly induced following 0.5 mmol/L VPA treatment in both N2a and 293T cells. CONCLUSIONS VPA can up-regulate the AnkG expression via directly increasing its transcription activity. Thus, the in vivo AnkG expression may be directly regulated by the VPA at transcriptional level.


Asunto(s)
Regiones Promotoras Genéticas , Animales , Ancirinas , Línea Celular , Vectores Genéticos , Humanos , Luciferasas , Ratones , Ratones Endogámicos C57BL , Regulación hacia Arriba , Ácido Valproico
17.
Mycorrhiza ; 24(3): 187-95, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24077881

RESUMEN

Spatial expansion of root hemiparasitic Pedicularis kansuensis in Bayanbulak Grassland of Xinjiang Uygur Autonomous Region (China) has caused great loss of herbage yield and has threatened the local livestock industry. Current management practices using manual eradication and chemical control have been proved problematic. Arbuscular mycorrhizal (AM) fungi have been suggested to be potential biocontrol agents against a number of plant pests, but experimental evidence is lacking against weedy P. kansuensis. In this study, we tested the hypothesis that inoculation with AM fungi will cause growth depression in P. kansuensis and reduce its damage to host plants. Based on the confirmation of AM status and host community of the hemiparasite in the field, a pot cultivation experiment was conducted to test the influence of an AM fungus (Glomus mosseae) on growth of P. kansuensis and the parasitized host (Elymus nutans). AM colonization was observed in roots of P. kansuensis, but the levels were much lower than those of its adjacent host species. A negative correlation between AM levels and the numbers of haustoria was detected for the field samples of the hemiparasite. Strong suppression of haustorium formation, a significant reduction in plant dry weight (DW), as well as marked reduction in the survival rate of P. kansuensis after inoculation with AM fungi was observed. In contrast, inoculation with G. mosseae increased root DW and whole plant DW of parasitized host plants. Our findings demonstrated significantly repressive effects of AM fungi on growth performance of P. kansuensis with and without the presence of a host. The potential of AM fungi as biocontrol agents against the damaging hemiparasite was confirmed.


Asunto(s)
Glomeromycota/fisiología , Micorrizas/fisiología , Pedicularis/microbiología , Malezas/microbiología , Control de Malezas/métodos , China , Pedicularis/crecimiento & desarrollo , Malezas/crecimiento & desarrollo
18.
Sci Total Environ ; 930: 172729, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38670353

RESUMEN

Pyruvic acid (PA) is a ubiquitous 2-oxocarboxylic acid in the atmosphere. Its photochemical process at the air-liquid (a-l) interface has been suggested as an important source of aqueous secondary organic aerosols. We investigated the photochemical reaction pathways of PA at the a-l interface using synchrotron-based vacuum ultraviolet single-photon ionization mass spectrometry (VUV SPI-MS) coupled with the System for Analysis at the Liquid Vacuum Interface (SALVI) microreactor. Results from mass spectral analysis and the determination of appearance energies (AEs) indicate that photolysis of PA can generate radicals, then they recombine with carboxylic acids and simple molecular oligomers. Furthermore, the preliminary products could form larger oligomers via radical reaction or esterification in the presence of hydroxyl and carboxyl functional groups. Mass spectral comparison shows that most photochemical reactions would complete within 4 h. The expanded photochemistry-driven reaction flowchart of PA is proposed based on the newly discovered products. Our results reveal that the interfacial PA photochemical reactions have different mechanisms from the bulk liquid due to the interfacial properties, such as molecular density, composition, and ion concentration. Our findings show that in situ mass spectral analysis with bright photon ionization is useful to elucidate the contribution of a-l interfacial reactions leading to aqSOA formation.

19.
Zool Res ; 45(4): 781-790, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38894521

RESUMEN

Precise targeting of specific regions within the central nervous system (CNS) is crucial for both scientific research and gene therapy in the context of brain diseases. Adeno-associated virus 13 (AAV13) is known for its restricted diffusion range within the CNS, making it an ideal choice for precise labeling and administration within small brain regions. However, AAV13 mediates relatively low expression of target genes. Here, we introduced specifically engineered modifications to the AAV13 capsid protein to enhance its transduction efficiency. We first constructed AAV13-YF by mutating tyrosine to phenylalanine on the surface of the AAV13 capsid. We then inserted the 7m8 peptide, known to enhance cell transduction, into positions 587/588 and 585/586 of the AAV13 capsid, resulting in two distinct variants named AAV13-587-7m8 and AAV13-585-7m8, respectively. We found that AAV13-YF exhibited superior in vitro infectivity in HEK293T cells compared to AAV13, while AAV13-587-7m8 and AAV13-585-7m8 showed enhanced CNS infection capabilities in C57BL/6 mice, with AAV13-587-7m8 infection retaining a limited spread range. These modified AAV13 variants hold promising potential for applications in gene therapy and neuroscience research.


Asunto(s)
Dependovirus , Ratones Endogámicos C57BL , Dependovirus/genética , Animales , Humanos , Ratones , Células HEK293 , Transducción Genética , Proteínas de la Cápside/genética , Proteínas de la Cápside/metabolismo
20.
Inorg Chem ; 52(10): 5742-8, 2013 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-23642088

RESUMEN

The electronically excited state and luminescence property of metal-organic framework Zn(3-tzba)(2,2'-bipy)(H2O)·nH2O have been investigated using the density functional theory (DFT) and time-dependent DFT (TDDFT). The calculated geometry and infrared spectra in the ground state are consistent with the experimental results. The frontier molecular orbitals and electronic configuration indicated that the origin of luminescence is attributed to a ligand-to-ligand charge transfer (LLCT). We theoretically demonstrated that the hydrogen bond H47···O5═C is weakened in the excited state S1; the weakening of the excited-state hydrogen bonding should be beneficial to the luminescence. To explore the effect of the water clusters on the luminescence, we studied four complexes Zn(3-tzba)(2,2'-bipy)(H2O)·3H2O, Zn(3-tzba)(2,2'-bipy)(H2O)·2H2O, Zn(3-tzba)(2,2'-bipy)(H2O)·H2O, and Zn(3-tzba)(2,2'-bipy)(H2O). The results reveal that the presence of water should play an important role in the emission characteristics of the MOF. Also, the UV-vis absorption and emission spectra of Zn(3-tzba)(2,2'-bipy)(H2O)·3H2O are in good agreement with the experimental results.


Asunto(s)
2,2'-Dipiridil/química , Luminiscencia , Compuestos Organometálicos/química , Agua/química , Zinc/química , Electrones , Enlace de Hidrógeno , Teoría Cuántica
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