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1.
Mol Cell ; 83(23): 4398-4412.e4, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-37995690

RESUMEN

The DNA replication of mpox virus is performed by the viral polymerase F8 and also requires other viral factors, including processivity factor A22, uracil DNA glycosylase E4, and phosphoprotein H5. However, the molecular roles of these viral factors remain unclear. Here, we characterize the structures of F8-A22-E4 and F8-A22-E4-H5 complexes in the presence of different primer-template DNA substrates. E4 is located upstream of F8 on the template single-stranded DNA (ssDNA) and is catalytically active, highlighting a functional coupling between DNA base-excision repair and DNA synthesis. Moreover, H5, in the form of tetramer, binds to the double-stranded DNA (dsDNA) region downstream of F8 in a similar position as PCNA (proliferating cell nuclear antigen) does in eukaryotic polymerase complexes. Omission of H5 or disruption of its DNA interaction showed a reduced synthesis of full-length DNA products. These structures provide snapshots for the working cycle of the polymerase and generate insights into the mechanisms of these essential factors in viral DNA replication.


Asunto(s)
Replicación del ADN , ADN Polimerasa Dirigida por ADN , ADN Polimerasa Dirigida por ADN/metabolismo , Monkeypox virus/genética , Monkeypox virus/metabolismo , Replicación Viral , ADN Viral/genética , Antígeno Nuclear de Célula en Proliferación/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo
2.
Nature ; 626(7998): 347-356, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38267576

RESUMEN

To survive in a complex social group, one needs to know who to approach and, more importantly, who to avoid. In mice, a single defeat causes the losing mouse to stay away from the winner for weeks1. Here through a series of functional manipulation and recording experiments, we identify oxytocin neurons in the retrochiasmatic supraoptic nucleus (SOROXT) and oxytocin-receptor-expressing cells in the anterior subdivision of the ventromedial hypothalamus, ventrolateral part (aVMHvlOXTR) as a key circuit motif for defeat-induced social avoidance. Before defeat, aVMHvlOXTR cells minimally respond to aggressor cues. During defeat, aVMHvlOXTR cells are highly activated and, with the help of an exclusive oxytocin supply from the SOR, potentiate their responses to aggressor cues. After defeat, strong aggressor-induced aVMHvlOXTR cell activation drives the animal to avoid the aggressor and minimizes future defeat. Our study uncovers a neural process that supports rapid social learning caused by defeat and highlights the importance of the brain oxytocin system in social plasticity.


Asunto(s)
Agresión , Reacción de Prevención , Hipotálamo , Vías Nerviosas , Neuronas , Oxitocina , Aprendizaje Social , Animales , Ratones , Agresión/fisiología , Reacción de Prevención/fisiología , Señales (Psicología) , Miedo/fisiología , Hipotálamo/citología , Hipotálamo/metabolismo , Vías Nerviosas/fisiología , Neuronas/metabolismo , Oxitocina/metabolismo , Receptores de Oxitocina/metabolismo , Conducta Social , Aprendizaje Social/fisiología , Núcleo Supraóptico/citología , Núcleo Supraóptico/metabolismo , Núcleo Hipotalámico Ventromedial/citología , Núcleo Hipotalámico Ventromedial/metabolismo , Plasticidad Neuronal
3.
Nat Rev Neurosci ; 24(11): 672-692, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37773070

RESUMEN

Excitation-transcription coupling (E-TC) links synaptic and cellular activity to nuclear gene transcription. It is generally accepted that E-TC makes a crucial contribution to learning and memory through its role in underpinning long-lasting synaptic enhancement in late-phase long-term potentiation and has more recently been linked to late-phase long-term depression: both processes require de novo gene transcription, mRNA translation and protein synthesis. E-TC begins with the activation of glutamate-gated N-methyl-D-aspartate-type receptors and voltage-gated L-type Ca2+ channels at the membrane and culminates in the activation of transcription factors in the nucleus. These receptors and ion channels mediate E-TC through mechanisms that include long-range signalling from the synapse to the nucleus and local interactions within dendritic spines, among other possibilities. Growing experimental evidence links these E-TC mechanisms to late-phase long-term potentiation and learning and memory. These advances in our understanding of the molecular mechanisms of E-TC mean that future efforts can focus on understanding its mesoscale functions and how it regulates neuronal network activity and behaviour in physiological and pathological conditions.


Asunto(s)
Plasticidad Neuronal , Receptores de N-Metil-D-Aspartato , Humanos , Receptores de N-Metil-D-Aspartato/metabolismo , Plasticidad Neuronal/fisiología , Potenciación a Largo Plazo/fisiología , Neuronas/metabolismo , Sinapsis/metabolismo , Expresión Génica , Hipocampo/fisiología
4.
J Am Chem Soc ; 146(3): 1832-1838, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38206810

RESUMEN

Isomerism in covalent organic frameworks (COFs) has scarcely been known. Here, for the first time we show 3D COFs with three framework isomers or polymorphs constructed from the same building blocks. All isomers were obtained as large (>10 µm) crystals; although their crystal shapes were distinctly different, they showed identical FT-IR and solid-state NMR spectra. Our structural analyses revealed unprecedented triple isomerism in 3D COFs (noninterpenetrated dia, qtz, and 3-fold interpenetrated dia-c3 nets). Furthermore, this Communication reports the first known COF with qtz topology for which the structure determination was based on Rietveld analysis. We achieved triple framework isomerism by reticulating a tetrahedral building block with a flexible junction and a linear building block with PEO side chains and by varying solution compositions. Our energy calculations, along with the discovery of interisomer transition, revealed that the isomer with qtz topology was a kinetic isomer. Thus, this simple yet little-explored concept of reticulating only flexible building blocks is an effective pathway to significantly broaden the diversity of 3D COFs, which have been proposed for a myriad of applications.

5.
Curr Issues Mol Biol ; 46(4): 3342-3352, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38666939

RESUMEN

Increasing the soybean-planting area and increasing the soybean yield per unit area are two effective solutions to improve the overall soybean yield. Northeast China has a large saline soil area, and if soybeans could be grown there with the help of isolated saline-tolerant rhizobia, the soybean cultivation area in China could be effectively expanded. In this study, soybeans were planted in soils at different latitudes in China, and four strains of rhizobia were isolated and identified from the soybean nodules. According to the latitudes of the soil-sampling sites from high to low, the four isolated strains were identified as HLNEAU1, HLNEAU2, HLNEAU3, and HLNEAU4. In this study, the isolated strains were identified for their resistances, and their acid and saline tolerances and nitrogen fixation capacities were preliminarily identified. Ten representative soybean germplasm resources in Northeast China were inoculated with these four strains, and the compatibilities of these four rhizobium strains with the soybean germplasm resources were analyzed. All four isolates were able to establish different extents of compatibility with 10 soybean resources. Hefeng 50 had good compatibility with the four isolated strains, while Suinong 14 showed the best compatibility with HLNEAU2. The isolated rhizobacteria could successfully establish symbiosis with the soybeans, but host specificity was also present. This study was a preliminary exploration of the use of salinity-tolerant rhizobacteria to help the soybean nitrogen fixation in saline soils in order to increase the soybean acreage, and it provides a valuable theoretical basis for the application of saline-tolerant rhizobia.

6.
BMC Plant Biol ; 24(1): 370, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714932

RESUMEN

BACKGROUND: Nymphaea (waterlily) is known for its rich colors and role as an important aquatic ornamental plant globally. Nymphaea atrans and some hybrids, including N. 'Feitian 2,' are more appealing due to the gradual color change of their petals at different flower developmental stages. The petals of N. 'Feitian 2' gradually change color from light blue-purple to deep rose-red throughout flowering. The mechanism of the phenomenon remains unclear. RESULTS: In this work, flavonoids in the petals of N. 'Feitian 2' at six flowering stages were examined to identify the influence of flavonoid components on flower color changes. Additionally, six cDNA libraries of N. 'Feitian 2' over two blooming stages were developed, and the transcriptome was sequenced to identify the molecular mechanism governing petal color changes. As a result, 18 flavonoid metabolites were identified, including five anthocyanins and 13 flavonols. Anthocyanin accumulation during flower development is the primary driver of petal color change. A total of 12 differentially expressed genes (DEGs) in the flavonoid biosynthesis pathway were uncovered, and these DEGs were significantly positively correlated with anthocyanin accumulation. Six structural genes were ultimately focused on, as their expression levels varied significantly across different flowering stages. Moreover, 104 differentially expressed transcription factors (TFs) were uncovered, and three MYBs associated with flavonoid biosynthesis were screened. The RT-qPCR results were generally aligned with high-throughput sequencing results. CONCLUSIONS: This research offers a foundation to clarify the mechanisms underlying changes in the petal color of waterlilies.


Asunto(s)
Flavonoides , Flores , Regulación de la Expresión Génica de las Plantas , Nymphaea , Transcriptoma , Flores/genética , Flores/crecimiento & desarrollo , Flores/metabolismo , Flavonoides/biosíntesis , Flavonoides/metabolismo , Nymphaea/genética , Nymphaea/metabolismo , Pigmentación/genética , Antocianinas/biosíntesis , Antocianinas/metabolismo , Perfilación de la Expresión Génica , Color
7.
Small ; : e2404219, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39212621

RESUMEN

Designing effective multifunctional nanodrugs to achieve multimodal treatment of tumors is an ideal choice to improve the poor clinical outcomes of current anti-tumor therapies. Here, a multifunctional nanomicelle DC@H loaded with sarcoma kinase and cyclooxygenase-2 protein dual target inhibitor DI02 is designed and prepared, which is sequentially catalyzed by carboxylesterase and glutathione for reduction, and strengthens the inhibition of cancer stem cell (CSC) related protein STAT3. The camptothecin carried by the DC@H ensures the effectiveness of chemotherapy. Ultimately, DC@H precisely releases and achieves effective inhibition of xenograft tumors based on the combination of chemotherapy, targeted therapy, and chemodynamic therapy, with a tumor inhibition rate of up to 90.89% in BALB/c nude mice. Research on lung metastasis proves that the CSC inhibitory characteristic of DC@H is a direct cause of the elimination of tumor metastatic nodules. There is no doubt that the multifunctional nano drug DC@H, which effectuates the collective elimination of breast cancer and cancer stem cells, provides a promising direction for achieving complete tumor cure in clinical practice.

8.
Small ; 20(8): e2304734, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37828641

RESUMEN

Lithium metal-based rechargeable batteries are attracting increasing attention due to their high theoretical specific capacity and energy density. However, the dendrite growth leads to short circuits or even explosions and rapid depletion of active materials and electrolytes. Here, a functionalized and laminated scaffold (PVDF/TiO@C fiber) based on lithiophilic titanium monoxide is rationally designed to inhibit dendrite growth. Specifically, the bottom TiO@C fiber sublayer provides rich Li nucleation sites and facilitates the formation of stable solid electrolyte interphase. Together with the top lithiophobic PVDF sublayer, the prepared freestanding scaffold can effectively suppress the growth of Li dendrite and ensure stable Li plating/stripping. Based on the dendrite-free deposition, the Li/PVDF/TiO@ C fiber anode enables over 1000 h at a current density of 1 mA cm-2 in a symmetrical cell and delivers superior electrochemical performance in both Li || LFP and Li-S batteries. The functional laminated fiber scaffold design provides essential insights for obtaining high-performance lithium metal anodes.

9.
Small ; 20(30): e2311657, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38461547

RESUMEN

A complex electromagnetic environment is a formidable challenge in national defense areas. Microwave-absorbing materials are considered as a strategy to tackle this challenge. In this work, lightweight, flexible, and thermal insulating Carbon/SiO2@CNTs (CSC) aerogel is successfully prepared coupled with outstanding microwave absorbing performance, through freeze-drying and high-temperature annealing techniques. The CSC aerogel shows a strong reflection loss (-55.16 dB) as well as wide effective absorbing bandwidth (8.5 GHz) in 2-18 GHz. It also retains good microwave absorption properties under tension and compression. Radar cross-sectional (RCS) simulation result demonstrates the CSC processing a strong reduction ability of RCS compared with a metal plate. Further exploration shows amazing flexibility and good thermal insulation properties of CSC. The successful preparation of this composite aerogel provides a broad prospect for the design of microwave-absorbing materials.

10.
BMC Neurosci ; 25(1): 8, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38350864

RESUMEN

Traumatic brain injury (TBI) is one of the leading causes of death and disability worldwide, and destruction of the cerebrovascular system is a major factor in the cascade of secondary injuries caused by TBI. Laser speckle imaging (LSCI)has high sensitivity in detecting cerebral blood flow. LSCI can visually show that transcranial focused ultrasound stimulation (tFUS) treatment stimulates angiogenesis and increases blood flow. To study the effect of tFUS on promoting angiogenesis in Controlled Cortical impact (CCI) model. tFUS was administered daily for 10 min and for 14 consecutive days after TBI. Cerebral blood flow was measured by LSCI at 1, 3, 7 and 14 days after trauma. Functional outcomes were assessed using LSCI and neurological severity score (NSS). After the last test, Nissl staining and vascular endothelial growth factor (VEGF) were used to assess neuropathology. TBI can cause the destruction of cerebrovascular system. Blood flow was significantly increased in TBI treated with tFUS. LSCI, behavioral and histological findings suggest that tFUS treatment can promote angiogenesis after TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Factor A de Crecimiento Endotelial Vascular , Ratones , Animales , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/terapia , Lesiones Traumáticas del Encéfalo/patología , Circulación Cerebrovascular/fisiología
11.
Phys Rev Lett ; 133(7): 070402, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39213546

RESUMEN

Entanglement propagation provides a key routine to understand quantum many-body dynamics in and out of equilibrium. Entanglement entropy (EE) usually approaches to a subsaturation known as the Page value S[over ˜]_{P}=S[over ˜]-dS (with S[over ˜] the maximum of EE and dS the Page correction) in, e.g., the random unitary evolutions. The ballistic spreading of EE usually appears in the early time and will be deviated far before the Page value is reached. In this work, we uncover that the magnetic field that maximizes the EE robustly induces persistent ballistic spreading of entanglement in quantum spin chains. The linear growth of EE is demonstrated to persist until the maximal S[over ˜] (along with a flat entanglement spectrum) is reached. The robustness of ballistic spreading and the enhancement of EE under such an optimal control are demonstrated, considering particularly perturbing the initial state by random pure states (RPSs). These are argued as the results from the endomorphism of the time evolution under such an entanglement-enhancing optimal control for the RPSs.

12.
Langmuir ; 40(2): 1364-1372, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38175958

RESUMEN

Ostwald ripening, the dominant mechanism of droplet size growth for an O/W nanoemulsion at high surfactant concentrations, depends on micelles in the water phase and high aqueous solubility of oil, especially for spontaneously formed nanoemulsions. In our study, O/W nanoemulsions were formed spontaneously by mixing a water phase with an oil phase containing fatty alcohol polyoxypropylene polyoxyethylene ether (APE). By monitoring periodically the droplet size of the nanoemulsions via dynamic light scattering, we demonstrated that the formed O/W nanoemulsions are stable against Ostwald ripening, i.e., droplet growth. In contrast, the nanoemulsion droplets grew with the addition of micelles, demonstrating the pivotal role of the presence of micelles in the water phase in the occurrence of Ostwald ripening. The influence of the initial phase of APE, the oil or water phase in which APE is present, on the micelle formation is discussed by the partition coefficient and interfacial adsorption of APE between the oil and water phase using a surface and interfacial tensiometer. In addition, the spontaneously formed O/W nanoemulsion, which is stable against Ostwald ripening, can be used as a nanocarrier for the delivery of water-insoluble pesticides. These results provide a novel approach for the preparation of stable nanoemulsions and contribute to elucidating the mechanism of instability of nanoemulsions.

13.
Langmuir ; 40(35): 18727-18735, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39159299

RESUMEN

ß-Glucosidase (ß-G) holds promising applications in various fields, such as biomass energy, food, pharmaceuticals, and environmental protection, yet its industrial application is still limited by issues of stability and recycling. Herein, we first immobilized ß-G onto the surface of magnetic chitosan nanoparticles (MCS/ß-G) through adsorption methods. Subsequently, utilizing the metal-organic framework (MOF), CaBDC, which possesses good stability under acidic conditions, we encapsulated MCS/ß-G. The resulting biocatalyst (MCS/ß-G@CaBDC) exhibited excellent activity and recyclability. MCS/ß-G@CaBDC can convert 91.5% of cellobiose to glucose in 60 min and maintained 81.9% activity after 10 cycles. The apparent Km value of MCS/ß-G@CaBDC was 0.148 mM, lower than free ß-G (0.166 mM) and MCS/ß-G (0.173 mM). The CaBDC layer increased the mass transfer resistance of the reaction but also triggered structural rearrangement of ß-G during the encapsulation process. This resulted in the ß-sheet content rising to 68.4%, which, in turn, contributed to enhancing the rigidity of ß-G. Moreover, the saturated magnetic strength of this biocatalyst could reach 37.3 emu/g, facilitating its magnetic recovery. The biocatalyst prepared in this study exhibits promising application prospects, and the immobilization method can provide valuable insights into the field of enzyme immobilization.


Asunto(s)
Celobiosa , Enzimas Inmovilizadas , Estructuras Metalorgánicas , beta-Glucosidasa , beta-Glucosidasa/química , beta-Glucosidasa/metabolismo , Celobiosa/química , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Estructuras Metalorgánicas/química , Hidrólisis , Calcio/química , Calcio/metabolismo , Estabilidad de Enzimas , Quitosano/química
14.
Phys Chem Chem Phys ; 26(15): 11738-11745, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38563831

RESUMEN

High-performance sodium-ion batteries (SIBs) require anode materials with high capacity and fast kinetics. Based on first-principles calculations, we propose BC3N2 and BC3N2/graphene (B/G) heterostructure as potential SIB anode materials. The BC3N2 monolayer exhibits intrinsic metallic behavior. In addition, BC3N2 possesses a low Na+ diffusion barrier (0.15 eV), a high storage capacity (777 mA h g-1), a low open-circuit voltage (0.72 V), and a tiny axial expansion (0.36%). Compared with the BC3N2 monolayer, the B/G heterostructure exhibits a lower diffusion barrier of 0.027 eV, suggesting a much faster diffusion. More importantly, although the B/G heterostructure possesses heavier molar weight, its theoretical capacity (689 mA h g-1) is comparable to that of the BC3N2 monolayer. Based on the above-mentioned properties, we hope both the BC3N2 monolayer and the B/G heterostructure would be promising anodes for SIBs.

15.
Bioorg Chem ; 150: 107551, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38971094

RESUMEN

Cancer is the most severe health problem facing most people today. Photodynamic therapy (PDT) for tumors has attracted attention because of its non-invasive nature, negligible adverse reactions, and high spatiotemporal selectivity. Developing biocompatible photosensitizers that can target, guide, and efficiently kill cancer cells is desirable in PDT. Here, two amphiphilic organic compounds, PS-I and PSS-II, were synthesized based on the D-π-A structure with a positive charge. The two AIEgens exhibited near-infrared emission, large Stokes shift, high 1O2 and O2-∙ generation efficiency, good biocompatibility, and photostability. They were co-incubated with cancer cells and eventually accumulated to lysosomes by cell imaging experiments. In vitro and in vivo experiments demonstrated that PS-I and PSS-II could effectively kill cancer cells and sufficiently inhibit tumor growth under light irradiation. PS-I had a higher fluorescence quantum yield in the aggregated state, which made it better for bio-imaging in imaging-guided photodynamic therapy. In contrast, PSS-II with a longer conjugated structure had more ROS generation to kill tumor cells under illumination, and the tumor growth inhibition of mice reached 71.95% during the treatment. No observable injury or undesirable outcomes were detected in the vital organs of the mice within the treatment group, suggesting that PSS-II/PS-I had a promising future in efficient imaging-guided PDT for cancer.


Asunto(s)
Rayos Infrarrojos , Lisosomas , Fotoquimioterapia , Fármacos Fotosensibilizantes , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/síntesis química , Humanos , Animales , Ratones , Estructura Molecular , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Ensayos de Selección de Medicamentos Antitumorales , Diseño de Fármacos , Relación Estructura-Actividad , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ratones Endogámicos BALB C , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Neoplasias Experimentales/diagnóstico por imagen , Supervivencia Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Femenino
16.
Bioorg Chem ; 150: 107612, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38986418

RESUMEN

The high level of tyrosinase leads to the generation of neuromelanin, further causing the abnormality of redox-related protein level and mediating the occurrence and development of Parkinson's disease (PD). However, the existing tyrosinase inhibitors are mostly natural product extracts or polyphenolic derivatives, which hindered them from penetrating the blood-brain barrier (BBB). Herein, we obtained a novel tyrosinase inhibitor, 2-06 (tyrosinase: monophenolase IC50 = 70.44 ± 22.69 µM, diphenolase IC50 = 1.89 ± 0.64 µM), through the structure-based screening method. The compound 2-06 presented good in vitro and in vivo safety, and can inhibit the tyrosinase and melanogenesis in B16F10. Moreover, this compound showed neuroprotective effects and Parkinsonism behavior improving function. 2-06 was proved to penetrate the BBB and enter the central nervous system (CNS). The exploration of the binding mode between 2-06 and tyrosinase provided the foundation for the subsequent structural optimization. This is the first research to develop a central-targeting tyrosinase inhibitor, which is crucial for in-depth study on the new strategy for utilizing tyrosinase inhibitors to treat PD.


Asunto(s)
Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Inhibidores Enzimáticos , Monofenol Monooxigenasa , Enfermedad de Parkinson , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Animales , Relación Estructura-Actividad , Ratones , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Estructura Molecular , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/síntesis química , Humanos , Masculino , Simulación del Acoplamiento Molecular , Barrera Hematoencefálica/metabolismo
17.
Acta Pharmacol Sin ; 45(9): 1912-1925, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38684800

RESUMEN

Ulcerative colitis (UC) is associated with changed dietary habits and mainly linked with the gut microbiota dysbiosis, necroptosis of epithelial cells, and mucosal ulcerations. Liver dysfunction and abnormal level of liver metabolism indices were identified in UC patients, suggesting a close interaction between gut and liver disorders. Methionine-choline deficient diet (MCD) has been shown to induce persistent alterations of gut microbiota and metabolome during hepatitis. In this study we further explored the disease phenotypes in UC patients and investigated whether MCD functioned as a trigger for UC susceptibility. After assessing 88 serum specimens from UC patients, we found significant liver dysfunction and dyslipidemia including abnormal ALT, AST, TG, TC, LDL-c and HDL-c. Liver dysfunction and dyslipidemia were confirmed in DSS-induced colitis mice. We fed mice with MCD for 14 days to cause mild liver damage, and then treated with DSS for 7 days. We found that MCD intake significantly exacerbated the pathogenesis of mucosal inflammation in DSS-induced acute, progressive, and chronic colitis, referring to promotion of mucosal ulcers, colon shortening, diarrhea, inflammatory immune cell infiltration, cytokines release, and abnormal activation of inflammatory macrophages in colon and liver specimens. Intraperitoneal injection of clodronate liposomes to globally delete macrophages dramatically compromised the pathogenesis of MCD-triggering colitis. In addition, MCD intake markedly changed the production pattern of short-chain fatty acids (SCFAs) in murine stools, colons, and livers. We demonstrated that MCD-induced colitis pathogenesis largely depended on the gut microbes and the disease phenotypes could be transmissible through fecal microbiota transplantation (FMT). In conclusion, this study supports the concept that intake of MCD predisposes to experimental colitis and enhances its pathogenesis via modulating gut microbes and macrophages in mice.


Asunto(s)
Sulfato de Dextran , Microbioma Gastrointestinal , Macrófagos , Metionina , Ratones Endogámicos C57BL , Animales , Metionina/deficiencia , Macrófagos/metabolismo , Macrófagos/inmunología , Masculino , Ratones , Sulfato de Dextran/toxicidad , Humanos , Colitis Ulcerosa/microbiología , Colitis Ulcerosa/patología , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/inmunología , Deficiencia de Colina/complicaciones , Femenino , Dieta , Colina/metabolismo , Colon/patología , Colon/microbiología , Colon/inmunología , Colitis/microbiología , Colitis/patología , Colitis/inducido químicamente , Hígado/patología , Hígado/metabolismo
18.
Environ Res ; 254: 119155, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38754614

RESUMEN

Fungi play an important role in the mineralization and humification of refractory organic matter such as lignocellulose during composting. However, limited research on the ecological role of fungi in composting system hindered the development of efficient microbial agents. In this study, six groups of lab-scale composting experiments were conducted to reveal the role of fungal community in composting ecosystems by comparing them with bacterial community. The findings showed that the thermophilic phase was crucial for organic matter degradation and humic acid formation. The Richness index of the fungal community peaked at 1165 during this phase. PCoA analysis revealed a robust thermal stability in the fungal community. Despite temperature fluctuations, the community structure, predominantly governed by Pichia and Candida, remained largely unaltered. The stability of fungal community and the complexity of ecological networks were 1.26 times and 5.15 times higher than those observed in bacterial community, respectively. Fungi-bacteria interdomain interaction markedly enhanced network complexity, contributing to maintain microbial ecological functions. The core fungal species belonging to the family Saccharomycetaceae drove interdomain interaction during thermophilic phase. This study demonstrated the key role of fungi in the composting system, which would provide theoretical guidance for the development of high efficiency composting agents to strengthen the mineralization and humification of organic matter.

19.
Cell Mol Life Sci ; 80(6): 148, 2023 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-37178259

RESUMEN

Mutations in GJB2 (Gap junction protein beta 2) are the most common genetic cause of non-syndromic hereditary deafness in humans, especially the 35delG and 235delC mutations. Owing to the homozygous lethality of Gjb2 mutations in mice, there are currently no perfect mouse models carrying Gjb2 mutations derived from patients for mimicking human hereditary deafness and for unveiling the pathogenesis of the disease. Here, we successfully constructed heterozygous Gjb2+/35delG and Gjb2+/235delC mutant mice through advanced androgenic haploid embryonic stem cell (AG-haESC)-mediated semi-cloning technology, and these mice showed normal hearing at postnatal day (P) 28. A homozygous mutant mouse model, Gjb235delG/35delG, was then generated using enhanced tetraploid embryo complementation, demonstrating that GJB2 plays an indispensable role in mouse placenta development. These mice exhibited profound hearing loss similar to human patients at P14, i.e., soon after the onset of hearing. Mechanistic analyses showed that Gjb2 35delG disrupts the function and formation of intercellular gap junction channels of the cochlea rather than affecting the survival and function of hair cells. Collectively, our study provides ideal mouse models for understanding the pathogenic mechanism of DFNB1A-related hereditary deafness and opens up a new avenue for investigating the treatment of this disease.


Asunto(s)
Sordera , Pérdida Auditiva Sensorineural , Humanos , Ratones , Animales , Conexinas/genética , Conexina 26/genética , Sordera/genética , Pérdida Auditiva Sensorineural/genética , Mutación , Audición
20.
Lipids Health Dis ; 23(1): 118, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38649986

RESUMEN

BACKGROUND: The present study was performed to assess the association between the neutrophil-to-apolipoprotein A1 ratio (NAR) and outcomes in patients with acute decompensated heart failure (ADHF) at different glucose metabolism states. METHODS: We recruited 1233 patients with ADHF who were admitted to Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University from December 2014 to October 2019. The endpoints were defined as composites of cardiovascular death, nonfatal myocardial infarction, nonfatal ischemic stroke and exacerbation of chronic heart failure. The restricted cubic spline was used to determine the best cutoff of NAR, and patients were divided into low and high NAR groups. Kaplan-Meier plots and multivariable Cox proportional hazard models were used to investigate the association between NAR and the risk of adverse outcomes. RESULTS: During the five-year follow-up period, the composite outcome occurred in 692 participants (56.1%). After adjusting for potential confounding factors, a higher NAR was associated with a higher incidence of composite outcomes in the total cohort (Model 1: HR = 1.42, 95% CI = 1.22-1.65, P<0.001; Model 2: HR = 1.29, 95% CI = 1.10-1.51, P = 0.002; Model 3: HR = 1.20, 95% CI = 1.01-1.42, P = 0.036). At different glucose metabolic states, a high NAR was associated with a high risk of composite outcomes in patients with diabetes mellitus (DM) (Model 1: HR = 1.54, 95% CI = 1.25-1.90, P<0.001; Model 2: HR = 1.40, 95% CI = 1.13-1.74, P = 0.002; Model 3: HR = 1.31, 95% CI = 1.04-1.66, P = 0.022), and the above association was not found in patients with prediabetes mellitus (Pre-DM) or normal glucose regulation (NGR) (both P>0.05). CONCLUSIONS: The NAR has predictive value for adverse outcomes of ADHF with DM, which implies that the NAR could be a potential indicator for the management of ADHF.


Asunto(s)
Apolipoproteína A-I , Insuficiencia Cardíaca , Neutrófilos , Humanos , Masculino , Femenino , Insuficiencia Cardíaca/sangre , Apolipoproteína A-I/sangre , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Neutrófilos/metabolismo , Glucemia/metabolismo , Modelos de Riesgos Proporcionales , Estimación de Kaplan-Meier , Factores de Riesgo , Pronóstico
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