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1.
Med Sci Monit ; 30: e944243, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39049468

RESUMEN

BACKGROUND General paresis of the insane (GPI) is characterized by cognitive impairment, neuropsychiatric symptoms, and brain structural abnormalities, mimicking many neuropsychiatric diseases. Olfactory dysfunction has been linked to cognitive decline and neuropsychiatric symptoms in numerous neuropsychiatric diseases. Nevertheless, it remains unclear whether patients with GPI experience olfactory dysfunction and whether olfactory dysfunction is associated with their clinical manifestations. MATERIAL AND METHODS Forty patients with GPI and 37 healthy controls (HCs) underwent the "Sniffin Sticks" test battery, Mini-Mental State Examination, and Neuropsychiatric Inventory to measure olfactory function, cognitive function, and neuropsychiatric symptoms, respectively. Brain structural abnormalities were evaluated using visual assessment scales including the medial temporal lobe atrophy (MTA) visual rating scale and Fazekas scale. RESULTS Compared with HCs, patients with GPI exhibited significant olfactory dysfunction, as indicated by deficits in the odor threshold (OT) (P=0.001), odor discrimination (OD) (P<0.001), and odor identification (OI) (P<0.001). In patients with GPI, the OI was positively correlated with cognitive function (r=0.57, P<0.001), but no significant correlation was found between olfactory function and neuropsychiatric symptoms, blood, or cerebrospinal fluid biomarkers (rapid plasma reagin circle card test and Treponema pallidum particle agglutination test), or brain structural abnormalities (MTA and Fazekas scale scores). Mediation analysis indicated that the impaired OI in patients with GPI was mediated by cognitive impairment and impaired OT respectively. CONCLUSIONS Patients with GPI exhibited overall olfactory dysfunction. OI is correlated with cognitive function and the impaired OI is mediated by cognitive impairment in patients with GPI. Thus, OI may serve as a marker for reflecting cognitive function in patients with GPI.


Asunto(s)
Disfunción Cognitiva , Trastornos del Olfato , Humanos , Masculino , Disfunción Cognitiva/fisiopatología , Femenino , Persona de Mediana Edad , Trastornos del Olfato/fisiopatología , Trastornos del Olfato/diagnóstico , Anciano , Pruebas Neuropsicológicas , Adulto , Biomarcadores , Cognición/fisiología , Estudios de Casos y Controles , Olfato/fisiología , Paresia/fisiopatología
2.
Molecules ; 27(17)2022 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-36080278

RESUMEN

Linolenic acid (LA) is gaining more interest within the scientific community. This is because it has a potential medical role in reducing the risk of inflammation, carcinogenesis, atherosclerosis and diabetes and is a valuable nutraceutical for human health. The oleaginous fungus Mucor circinelloides produces a high lipid content (36%), including valuable polyunsaturated fatty acids (PUFAs). However, the critical step in which oleic acid (OA) is converted into LA is not efficient at supplying enough substrates for PUFA synthesis. Hence, we propose a method to increase LA production based on genetic engineering. The overexpression of the Δ12-desaturase gene from M. circinelloides and Mortierella alpina increased the LA content and improved the lipid accumulation (from 14.9% to 21.6% in the Δ12-desaturase gene of the M. circinelloides overexpressing strain (Mc-D12MC) and from 14.9% to 18.7% in the Δ12-desaturase gene of M. alpina overexpressing strain (Mc-D12MA)). Additionally, the up-regulated expression levels of these genes targeted the genes involved in NADPH production, implying that the elevated Δ12-desaturase gene may function as a critical regulator of NADPH and lipid synthesis in M. circinelloides. This study provides the first evidence to support the design of metabolic engineering related to LA and PUFA production in M. circinelloides for potential industrial applications.


Asunto(s)
Ácido Graso Desaturasas , Mucor , Ácido alfa-Linolénico , Ácido Graso Desaturasas/genética , Ácido Graso Desaturasas/metabolismo , Mucor/genética , NADP/metabolismo , Ácido alfa-Linolénico/biosíntesis
3.
Nano Lett ; 20(7): 5435-5442, 2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32491862

RESUMEN

High-performance lithium-ion batteries (LIBs) demand efficient and selective transport of lithium ions. Inspired by ion channels in biology systems, lithium-ion channels are constructed by chemically modifying the nanoporous channels of metal-organic frameworks (MOFs) with negatively charged sulfonate groups. Analogous to the biological ion channels, such pendant anionic moieties repel free anions while allowing efficient transport of cations through the pore channels. Implementing such MOFs as an electrolyte membrane doubly enhances the lithium-ion transference number, alleviates concentration polarization, and affords striking durability of high-rate LIBs. This work demonstrates an ion-selective material design that effectively tunes the ion-transport behavior and could assist with more efficient operation of LIBs.

4.
Small ; 16(24): e2000794, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32419375

RESUMEN

The development of lithium metal anodes capable of sustaining large volume changes, avoiding lithium dendrite formation, and remaining stable in ambient air is crucial for commercially viable lithium metal batteries. Toward this goal, the fabrication of porous and lithiophilic copper scaffolds via a powder metallurgy strategy is reported. Infiltrating the scaffolds with molten lithium followed by exposure to Freon R134a produces lithium metal anodes with dramatically improved rate performance and cycling stability. This work provides a simple yet effective route for the fabrication of safe, low-cost lithium metal batteries with high energy density.

5.
Soft Matter ; 12(2): 337-57, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-26509717

RESUMEN

Adaptive molecular self-assemblies provide possibility of constructing smart and functional materials in a non-covalent bottom-up manner. Exploiting the intrinsic properties of responsiveness of non-covalent interactions, a great number of fancy self-assemblies have been achieved. In this review, we try to highlight the recent advances in this field. The following contents are focused: (1) environmental adaptiveness, including smart self-assemblies adaptive to pH, temperature, pressure, and moisture; (2) special chemical adaptiveness, including nanostructures adaptive to important chemicals, such as enzymes, CO2, metal ions, redox agents, explosives, biomolecules; (3) field adaptiveness, including self-assembled materials that are capable of adapting to external fields such as magnetic field, electric field, light irradiation, and shear forces.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38052250

RESUMEN

Lipid biosynthesis is a significant metabolic response to nitrogen starvation in oleaginous fungi. The oleaginous fungus Mucor circinelloides copes with nitrogen stress by degrading AMP through AMP deaminase (AMPD). However, the mechanism of AMPD in regulating lipogenesis remains largely unclear. To elucidate the mechanism of AMPD in lipid synthesis in this M. circinelloides, we identified two genes (ampd1 and ampd2) encoding AMPD and constructed an ampd double knockout mutant. The engineered M. circinelloides strain elevated cell growth and lipid accumulation, as well as the content of oleic acid (OA) and gamma-linolenic acid (GLA). In addition to the expected increase in transcription levels of genes associated with lipid and TAG synthesis, we observed suppression of lipid degradation and reduced amino acid biosynthesis. This suggested that the deletion of AMPD genes induces the redirection of carbon towards lipid synthesis pathways. Moreover, the pathways related to nitrogen metabolism, including nitrogen assimilation and purine metabolism (especially energy level), were also affected in order to maintain homeostasis. Further analysis discovered that the transcription factors (TFs) related to lipid accumulation were also regulated. This study provides new insights into lipid biosynthesis in M. circinelloides, indicating that the trigger for lipid accumulation is not entirely AMPD-dependent and suggest that there may be additional mechanisms involved in the initiation of lipogenesis.


Asunto(s)
AMP Desaminasa , Metabolismo de los Lípidos , Mucor , Metabolismo de los Lípidos/genética , AMP Desaminasa/genética , AMP Desaminasa/metabolismo , Nitrógeno/metabolismo , Lípidos
7.
J Agric Food Chem ; 71(42): 15680-15691, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37822229

RESUMEN

Lipid accumulation in oleaginous organisms is initiated by AMP deaminase (AMPD) after nitrogen depletion because it mediates the concentration of intracellular adenosine monophosphate (AMP). However, the role of AMPD in lipogenesis in the oleaginous fungus Mucor circinelloides is largely unknown. Therefore, we identified the genes (ampd1 and ampd2) encoding AMPD and investigated the role of AMPD in lipid synthesis in this fungus by overexpressing and deleting ampd genes. Deletion of ampd1 and ampd2 caused 21 and 28% increments in lipid contents under N-limited conditions, respectively. These increases were correlated with the activation of enzymes involved in lipogenesis and the alteration of energy balance. Unexpectedly, overexpression of ampd genes affected nitrogen consumption in both N-limited and N-excess media, which resulted in an increase in cell growth and lipid accumulation compared with the control strain when nitrogen was available. Furthermore, the increased lipid accumulation in the ampd-overexpressing mutants in N-excess media was accompanied by enhanced activities of lipid biosynthetic enzymes. These data suggested that nitrogen metabolism and energy metabolism are affected by AMPD, and overexpression of ampd genes induced lipid accumulation under nitrogen-rich conditions by mimicking the nitrogen limitation response. This highlights an intriguing function of AMPD in M. circinelloides.


Asunto(s)
AMP Desaminasa , Lipogénesis , Metabolismo de los Lípidos , AMP Desaminasa/genética , AMP Desaminasa/metabolismo , Mucor/genética , Mucor/metabolismo , Lípidos , Nitrógeno/metabolismo
8.
Front Microbiol ; 13: 1078157, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36590442

RESUMEN

Mucor circinelloides WJ11, an oleaginous filamentous fungus, produces 36% lipid of its cell dry weight when cultured in a high C/N ratio medium, however, the yield of γ-linolenic acid (GLA) is insufficient to make it competitive with other plant sources. To increase the GLA content in M. circinelloides WJ11, this fungus was engineered by overexpression of its key genes such as Δ6-, Δ12-, and Δ9-desaturases involved in GLA production. Firstly, we tried to overexpress two Δ6-desaturase isozymes to determine which one played important role in GLA synthesis. Secondly, Δ6-and Δ12-desaturase were co-overexpressed to check whether linoleic acid (LA), the precursor for GLA synthesis, is a limiting factor or not. Moreover, we tried to explore the effects of simultaneous overexpression of Δ6-, Δ12-, and Δ9-desaturases on GLA production. Our results showed that overexpression (1 gene) of DES61 promoted higher GLA content (21% of total fatty acids) while co-overexpressing (2 genes) DES61 and DES12 and simultaneous overexpressing (3 genes) DES61, DES12, and DES91 increased the GLA production of engineered strains by 1.5 folds and 1.9 folds compared to the control strain, respectively. This study provided more insights into GLA biosynthesis in oleaginous fungi and laid a foundation for further increase in GLA production into fungus such as M. circinelloides.

9.
Front Microbiol ; 12: 774825, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34867915

RESUMEN

The fungus, Mucor lusitanicus, is of great interest for microbial lipids, because of its ability to accumulate intracellular lipid using various carbon sources. The biosynthesis of fatty acid requires the reducing power NADPH, and acetyl-CoA, which is produced by the cleavage of citrate in cytosol. In this study, we employed different strategies to increase lipid accumulation in the low lipid-producing fungi via metabolic engineering technology. Hence, we constructed the engineered strain of M. lusitanicus CBS 277.49 by using malate transporter (mt) and 2-oxoglutarate: malate antiporter (sodit) from M. circinelloides WJ11. In comparison with the control strain, the lipid content of the overexpressed strains of mt and sodit genes were increased by 24.6 and 33.8%, respectively. These results showed that mt and sodit can affect the distribution of malate in mitochondria and cytosol, provide the substrates for the synthesis of citrate in the mitochondria, and accelerate the transfer of citrate from mitochondria to cytosol, which could play a significant regulatory role in fatty acid synthesis leading to lipids over accumulation.

10.
ACS Appl Mater Interfaces ; 12(35): 39127-39134, 2020 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-32805915

RESUMEN

Silicon is one of the most promising anode materials for lithium-ion batteries due to its high theoretical capacity and low cost. However, significant capacity fading caused by severe structural degradation during cycling limits its practical implication. To overcome this barrier, we design a covalently bonded nanocomposite of silicon and poly(vinyl alcohol) (Si-PVA) by high-energy ball-milling of a mixture of micron-sized Si and PVA. The obtained Si nanoparticles are wrapped by resilient PVA coatings that covalently bond to the Si particles. In such nanostructures, the soft PVA coatings can accommodate the volume change of the Si particles during repeated lithiation and delithiation. Simultaneously, as formed covalent bonds enhance the mechanical strength of the coatings. Due to the significantly improved structural stability, the Si-PVA composite delivers a lifespan of 100 cycles with a high capacity of 1526 mAh g-1. In addition, a high initial Coulombic efficiency of over 86% and an average value of 99.2% in subsequent cycles can be achieved. This reactive ball-milling strategy provides a low-cost and scalable route to fabricate high-performance anode materials.

11.
Nanoscale ; 12(26): 13918-13925, 2020 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32588865

RESUMEN

Particular recent interest has been given to the Li2TiSiO5 (LTSO) anode material owing to its low lithiation potential (0.28 V vs. Li/Li+) and decent theoretical capacity (308 mA h g-1). However, its poor electronic conductivity (∼10-7 S m-1) fundamentally limits the utilization of this material, and current strategies fail to tackle such issues in practical ways. Herein, a hierarchical microparticulate LTSO-carbon composite (LTSO/C) is fabricated by chemical vapor deposition (CVD), where microsized LTSO/C particles assembled from nanospheres guarantee a practical tap density of ∼1.3 g mL-1. Meanwhile, significantly elevated conductivity of LTSO/C (∼103 S m-1) is achieved by a thin layer (15 nm) of graphitic carbon growth on LTSO, which is theoretically catalyzed by the surface functional groups on the parent LTSO. The electrochemical characterization of LTSO/C reveals a superior graphite-like volumetric capacity of 441.1 mA h cm-3 and Li4Ti5O12-like rate capability (120.1 mA h cm-3 at 4.5 A g-1), providing inspiring guidance for designing analogous Ti or Si-based compounds for ultrafast lithium storage materials.

12.
ACS Appl Mater Interfaces ; 12(39): 43824-43832, 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-32896128

RESUMEN

A new family of solid-like electrolytes was developed by infiltrating MIL-100(Al), an electrochemically stable metal-organic-framework (MOF) material, with liquid electrolytes that contain cations from the 3rd period (Na+, Mg2+, and Al3+) and the 1st group (Li+, Na+, K+, and Cs+). The anions were immobilized within the MOF scaffolds upon complexing with the open metal sites, allowing effective transport of the cations in the nanoporous channels with high conductivity (up to 1 mS cm-1) and low activation energy (down to 0.2 eV). This general approach enables the fabrication of superior conductive solid-like electrolytes beyond lithium ions.

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