Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.446
Filtrar
1.
Small ; : e2406359, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225380

RESUMEN

Anode-free lithium-metal batteries (AFLMBs) are desirable candidates for achieving high-energy-density batteries, while severe active Li+ loss and uneven Li plating/stripping behavior impede their practical application. Herein, a trilaminar LS-Cu (LiCPON + Si/C-Cu) current collector is fabricated by radio frequency magnetron sputtering, including a Si/C hybrid lithiophilic layer and a supernatant carbon-incorporated lithium phosphorus oxynitride (LiCPON) solid-state electrolyte layer. Joint experimental and computational characterizations and simulations reveal that the LiCPON solid-state electrolyte layer can decompose into an in situ stout ion-transport-promoting protective layer, which can not only regulate homogeneous Li plating/stripping behavior but also inhibit the pulverization and deactivation of Si/C hybrid lithiophilic layer. When combined with surface prelithiated Li1.2Ni0.13Co0.13Mn0.54O2 (Preli-LRM) cathode, the Preli-LRM||LS-Cu full cell delivers 896.1 Wh kg-1 initially and retains 354.1 Wh kg-1 after 50 cycles. This strategy offers an innovative design of compensating for active Li+ loss and inducing uniform Li plating/stripping behavior simultaneously for the development of AFLMBs.

2.
Adv Sci (Weinh) ; : e2404854, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258786

RESUMEN

Cancer is a systemic heterogeneous disease involving complex molecular networks. Tumor formation involves an epithelial-mesenchymal transition (EMT), which promotes both metastasis and plasticity of cancer cells. Recent experiments have proposed that cancer cells can be transformed into adipocytes via a combination of drugs. However, the underlying mechanisms for how these drugs work, from a molecular network perspective, remain elusive. To reveal the mechanism of cancer-adipose conversion (CAC), this study adopts a systems biology approach by combing mathematical modeling and molecular experiments, based on underlying molecular regulatory networks. Four types of attractors are identified, corresponding to epithelial (E), mesenchymal (M), adipose (A) and partial/intermediate EMT (P) cell states on the CAC landscape. Landscape and transition path results illustrate that intermediate states play critical roles in the cancer to adipose transition. Through a landscape control approach, two new therapeutic strategies for drug combinations are identified, that promote CAC. These predictions are verified by molecular experiments in different cell lines. The combined computational and experimental approach provides a powerful tool to explore molecular mechanisms for cell fate transitions in cancer networks. The results reveal underlying mechanisms of intermediate cell states that govern the CAC, and identified new potential drug combinations to induce cancer adipogenesis.

3.
Cardiovasc Res ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39253986

RESUMEN

BACKGROUND: Folic acid (FA) supplementation during pregnancy aims to protect foetal development. However, maternal over-supplementation of FA has been demonstrated to cause metabolic dysfunction and increase the risk of autism, retinoblastoma, and respiratory illness in the offspring. Moreover, FA supplementation reduces the risk of congenital heart disease. However, little is known about its possible adverse effects on cardiac health resulting from maternal over-supplementation. In this study, we assessed the detrimental effects of maternal FA over-supplementation on the cardiac health of the offspring. METHODS AND RESULTS: Eight-week-old C57BL/6J pregnant mice were randomly divided into control and over-supplemented groups. The offspring cardiac function was assessed using echocardiography. Cardiac fibrosis was assessed in the left ventricular myocardium by histological analysis. Proteomic, protein, RNA, and DNA methylation analyses were performed by liquid chromatography-tandem mass spectrometry, western blotting, real-time quantitative PCR, and bisulfite sequencing, respectively. We found that maternal periconceptional FA over-supplementation impaired cardiac function with the decreased left ventricular ejection fraction in the offspring. Biochemical indices and tissue staining further confirmed impaired cardiac function in offspring caused by maternal FA over-supplementation. The combined proteomic, RNA expression, and DNA methylation analyses suggested that key genes involved in cardiac function were inhibited at the transcriptional level possibly due to increased DNA methylation. Among these, superoxide dismutase 1 was downregulated, and reactive oxygen species (ROS) levels increased in the mouse heart. Inhibition of ROS generation using the antioxidant N-acetylcysteine rescued the impaired cardiac function resulting from maternal FA over-supplementation. CONCLUSIONS: Our study revealed that over-supplementation with FA during mouse pregnancy is detrimental to cardiac function with the decreased left ventricular ejection fraction in the offspring and provides insights into the mechanisms underlying the association between maternal FA status and health outcomes in the offspring.

4.
ChemSusChem ; : e202401535, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39243152

RESUMEN

Anode-free Lithium metal batteries, with their high energy density (>500 Wh/kg), are emerging as a promising solution for high-energy-density rechargeable batteries. However, the Coulombic Efficiency and capacity often decline due to interface side reactions. To address this, a lithiophilic layer is introduced, promoting stable and uniform Li deposition. Despite its effectiveness, this layer often undergoes electrochemical deactivation over time. This work investigates lithiophilic silver (Ag), prepared via magnetron sputtering on a copper (Cu) current collector. Finite element simulations identify stress changes from alloying reactions as a key cause of Ag particle pulverization and deactivation. A high Young's modulus coating layer is proposed to mitigate this. The Ag2TiO3@Ag@TiO2@Cu composite electrode, designed with multi-layer structures, demonstrates a slower deactivation process through galvanostatic electrochemical cycling. Characterization methods such as SEM, AFM, and TEM confirm the suppression of Ag particle pulverization, while uncoated Ag fractures and deactivates. This work uncovers a potential failure mechanism of lithiophilic metallic nanoparticles and proposes a strategy for deactivation suppression using an artificial coating layer.

5.
J Affect Disord ; 368: 55-66, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39265869

RESUMEN

BACKGROUND: Previous observational studies have suggested that there appears to be a close association between mitochondrial function and psychiatric disorders, but whether a causal role exists remains unclear. METHODS: We extracted genetic instruments for 67 mitochondrial-related proteins and 10 psychiatric disorders from publicly available genome-wide association studies, and employed five distinct MR methods and false discovery rate correction to detect causal associations between them. Additionally, we conducted a series of sensitivity tests and additional model analysis to ensure the robustness of the results. For potential causal associations, we further performed reverse MR analyses to assess the impact of reverse causality. RESULTS: We identified a total of 2 significant causal associations and 24 suggestive causal associations. Specifically, Phenylalanine-tRNA ligase was found to increase the risk of Alzheimer's disease, while Mitochondrial glutamate carrier 2 decreased the risk of autism spectrum disorder. Furthermore, there was no evidence of significant pleiotropy, heterogeneity, or reverse causality. LIMITATIONS: This study was limited to individuals of European ancestry, and the conclusions drawn are merely revelatory. CONCLUSION: This study provides novel insights into the relationship between mitochondria and psychiatric disorders, as well as the pathogenesis and treatment strategies for psychiatric disorders.

6.
Sci Rep ; 14(1): 21331, 2024 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-39266656

RESUMEN

Programming cell signaling during T-cell activation represents a simple strategy for improving the potency of therapeutic T-cell products. Stim-R technology (Lyell Immunopharma) is a customizable, degradable synthetic cell biomimetic that emulates physiologic, cell-like presentation of signal molecules to control T-cell activation. A breadth of Stim-R formulations with different anti-CD3/anti-CD28 (αCD3/αCD28) antibody densities and stoichiometries were screened for their effects on multiple metrics of T-cell function. We identified an optimized formulation that produced receptor tyrosine kinase-like orphan receptor 1 (ROR1)-targeted chimeric antigen receptor (CAR) T cells with enhanced persistence and polyfunctionality in vitro, as assessed in repeat-stimulation assays, compared with a benchmark product generated using a conventional T-cell-activating reagent. In transcriptomic analyses, CAR T cells activated with Stim-R technology showed downregulation of exhaustion-associated gene sets and retained a unique subset of stem-like cells with effector-associated gene signatures following repeated exposure to tumor cells. Compared with the benchmark product, CAR T cells activated using the optimized Stim-R technology formulation exhibited higher peak expansion, prolonged persistence, and improved tumor control in a solid tumor xenograft model. Enhancing T-cell products with Stim-R technology during T-cell activation may help improve therapeutic efficacy against solid tumors.


Asunto(s)
Activación de Linfocitos , Receptores Quiméricos de Antígenos , Transducción de Señal , Linfocitos T , Receptores Quiméricos de Antígenos/inmunología , Receptores Quiméricos de Antígenos/metabolismo , Receptores Quiméricos de Antígenos/genética , Humanos , Animales , Activación de Linfocitos/inmunología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Ratones , Inmunoterapia Adoptiva/métodos , Ensayos Antitumor por Modelo de Xenoinjerto , Línea Celular Tumoral , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Antígenos de Linfocitos T/inmunología , Antígenos CD28/inmunología , Antígenos CD28/metabolismo
7.
Front Psychol ; 15: 1415552, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39286562

RESUMEN

Purpose: This study aims to explore the effectiveness of enhancing individual spatial cognitive abilities in alleviating the negative symptoms of visually induced motion sickness (VIMS). Additionally, it seeks to develop innovative intervention methods to improve spatial cognition and identify new treatment approaches for VIMS. Methods: The study investigated the impact of innovative interventions on spatial cognitive abilities and their modulation of VIMS susceptibility. A total of 43 participants were recruited (23 in the experimental group and 20 in the control group). The experimental group underwent six sessions of spatial cognitive ability training, while the control group engaged in activities unrelated to spatial cognition. Results: The analysis revealed that the spatial cognitive ability scores of the experimental group significantly improved after the intervention. Furthermore, the experimental group exhibited significant differences in nausea, oculomotor, disorientation, and total SSQ scores before and after the intervention, indicating that the intervention effectively mitigated VIMS symptoms. Conclusion: This study developed a virtual reality training method that effectively enhances individual spatial cognitive abilities and significantly alleviates VIMS symptoms, providing a novel and effective approach for VIMS intervention and treatment.

8.
Artículo en Inglés | MEDLINE | ID: mdl-39265038

RESUMEN

Industrial processes generate huge volumes of oily saline wastewater. Instead of being sent to the drainage system immediately, extracting osmotic energy from these effluents represents a promising means to reuse these wastes and contributes to mitigate the ever-growing energy crisis. Herein, an MOF-decorated PTFE membrane is engineered to extract osmotic energy from oily wastewaters. Copper hydroxide nanowires (CHNs) are intertwined with polystyrenesulfonate sodium (PSS), deposited onto a poly(tetrafluoroethylene) (PTFE) membrane, and thereafter used as metal precursors to in situ generate HKUST-1 doped with negative charges. The resulting HKUST-1PSS@PTFE hybrid membrane possesses abundant angstrom-scale channels capable of transporting cations efficiently and features a hierarchically structured surface with underwater superoleophobicity. The energy conversion performance of the HKUST-1PSS3.5@PTFE membrane can reach an output power density of 6.21 W m-2 at a 50-fold NaCl gradient, which is superior to those of pristine PTFE membranes. Once exposed to oily saline wastewater, the HKUST-1PSS@PTFE membrane can exhibit an excellent oil-repellent ability, thus contributing to sustain its osmotic energy harvesting. This work may promote the development of antifouling osmotic energy harvesters with a long working life and pave the way to fully exploit oily wastewater effluents as valuable energy sources.

9.
Inorg Chem ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39284105

RESUMEN

Although research on nitrosyl (NO) heme complexes and their one-electron reduced form, nitroxyl (or nitroxyl anion, NO-) derivatives, has been going on for decades, there are still disagreements about the electrical configuration of nitroxyl complexes, and the majority of the work on this topic is based on theoretical calculations. Following the initial nitroxyl iron porphyrin crystal structure, we present two further polymorphic forms of [CoCp2][Fe(TFPPBr8)(NO)]. Using the same completely halogenated porphyrin ligand, we also present two polymorphic forms of nitrosyl cobalt(II) complexes, which are another sort of {MNO}8 structure. In addition to the EXANES and EPR studies of these {FeNO}7 and {CoNO}8 complexes, the {FeNO}8 [CoCp2][Fe(TFPPBr8)(NO)] complex is also investigated by temperature-dependent Mössbauer experiments for the first time with the {FeNO}7 precursor as a control sample. The analysis of the Mössbauer and crystal structural parameters between these two types of {MNO}8 (M = Fe or Co) species and previously reported analogous ones allow us to conclude that the electronic configuration of [Fe(TFPPBr8)(NO)]- is best described as an intermediate between low-spin Fe(II)-NO- and Fe(I)-NO•.

10.
Nat Commun ; 15(1): 7682, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39227380

RESUMEN

The inversion of substrate size specificity is an evolutionary roadblock for proteins. The Duf4243 dioxygenases GedK and BTG13 are known to catalyze the aromatic cleavage of bulky tricyclic hydroquinone. In this study, we discover a Duf4243 dioxygenase PaD that favors small monocyclic hydroquinones from the penicillic-acid biosynthetic pathway. Sequence alignments between PaD and GedK and BTG13 suggest PaD has three additional motifs, namely motifs 1-3, distributed at different positions in the protein sequence. X-ray crystal structures of PaD with the substrate at high resolution show motifs 1-3 determine three loops (loops 1-3). Most intriguing, loops 1-3 stack together at the top of the pocket, creating a lid-like tertiary structure with a narrow channel and a clearly constricted opening. This drastically changes the substrate specificity by determining the entry and binding of much smaller substrates. Further genome mining suggests Duf4243 dioxygenases with motifs 1-3 belong to an evolutionary branch that is extensively involved in the biosynthesis of natural products and has the ability to degrade diverse monocyclic hydroquinone pollutants. This study showcases how natural enzymes alter the substrate specificity fundamentally by incorporating new small motifs, with a fixed overall scaffold-architecture. It will also offer a theoretical foundation for the engineering of substrate specificity in enzymes and act as a guide for the identification of aromatic dioxygenases with distinct substrate specificities.


Asunto(s)
Secuencias de Aminoácidos , Dioxigenasas , Especificidad por Sustrato , Dioxigenasas/metabolismo , Dioxigenasas/genética , Dioxigenasas/química , Cristalografía por Rayos X , Hidroquinonas/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Secuencia de Aminoácidos , Modelos Moleculares , Alineación de Secuencia
11.
Commun Eng ; 3(1): 128, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251731

RESUMEN

To address the growing demand from emerging applications, high transmission capacity is essential for both fibre backbones and last-mile communications. This can be achieved by integrating optical fibre with optical wireless technologies, facilitating the development of fibre-free-space optical communications. Here we report a bidirectional wavelength-division-multiplexing fibre-free-space optical communication employing polarisation multiplexing technique and tunable optical vestigial sideband filter. The transmission capacity is considerably increased by integrating the polarisation multiplexing technique with the wavelength-division-multiplexing scheme. The transmission performance is extensively enhanced by using a tunable optical vestigial sideband filter and vestigial sideband-four-level pulse amplitude modulation. Moreover, the optical wireless link is substantially extended through the operation of triplet lenses. Low bit error rates and clear vestigial sideband-four-level pulse amplitude modulation eye diagrams are attained with a high aggregate transmission capacity of 480 Gb/s for downstream/upstream transmission. This capability of bidirectional fibre-free-space optical communications holds substantial potential for enhancing advanced wired-wireless communications.

12.
Nat Commun ; 15(1): 7639, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39223144

RESUMEN

The Veratrum alkaloids are a class of highly intricate natural products renowned for their complex structural and stereochemical characteristics, which underlie a diverse array of pharmacological activities ranging from anti-hypertensive properties to antimicrobial effects. These properties have generated substantial interest among both synthetic chemists and biologists. While numerous advancements have been made in the synthesis of jervanine and veratramine subtypes over the past 50 years, the total synthesis of highly oxidized cevanine subtypes has remained relatively scarce. Building on the efficiency of our previously developed strategy for constructing the hexacyclic carbon skeleton of the Veratrum alkaloid family via a stereoselective intramolecular Diels-Alder reaction and radical cyclization, here we show the development of a unified synthetic approach to access highly oxidized Veratrum alkaloids. This includes the total synthesis of (-)-zygadenine, (-)-germine, (-)-protoverine and the alkamine of veramadine A, by capitalizing on a meticulously designed sequence of redox manipulations and a late-stage neighboring-group participation strategy.


Asunto(s)
Alcaloides de Veratrum , Estereoisomerismo , Alcaloides de Veratrum/síntesis química , Alcaloides de Veratrum/química , Alcaloides de Veratrum/farmacología , Oxidación-Reducción , Ciclización , Reacción de Cicloadición , Productos Biológicos/síntesis química , Productos Biológicos/química , Productos Biológicos/farmacología , Estructura Molecular
13.
Am J Reprod Immunol ; 92(2): e13916, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39166450

RESUMEN

BACKGROUND: Uterine endometrial cancer (UEC) is a common gynecological estrogen-dependent carcinoma, usually accompanied by intermenstrual bleeding. Active heme metabolism frequently plays an increasingly important role in many diseases, especially in cancers. Tumor-associated macrophages (TAMs) are the major population in the immune microenvironment of UEC. However, the roles of heme metabolisms in the crosstalk between UEC cells (UECCs) and macrophages are unclear. MATERIALS AND METHODS: In our study, by using TCGA database analysis, integration analysis of the protein-protein interaction (PPI) network and sample RNA transcriptome sequencing were done. The expression level of both heme-associated molecules and iron metabolism-related molecules were measured by quantitative real-time polymerase chain reaction. Heme level detection was done through dehydrohorseradish peroxidase assay. In addition to immunohistochemistry, phagocytosis assay of macrophages, immunofluorescence staining, intracellular ferrous iron staining, as well as enzyme-linked immune sorbent assay were performed. RESULTS: In the study, we verified that heme accumulation in UECCs is apparently higher than in endometrial epithelium cells. Low expression of succinate dehydrogenase B under the regulation of estrogen contributes to over-production of succinate and heme accumulation in UECC. More importantly, excessive heme in UECCs impaired macrophage phagocytosis by regulation of CD36. Mechanistically, this process is dependent on toll-like receptor (TLR4)/type I interferons alpha (IFN Iα) regulatory axis in macrophage. CONCLUSION: Collectively, these findings elucidate that active heme metabolism of UECCs directly decreases phagocytosis by controlling the secretion of TLR4-mediated IFN Iα and the expression of CD36, and further contributing to the immune escape of UEC.


Asunto(s)
Antígenos CD36 , Neoplasias Endometriales , Hemo , Interferón Tipo I , Fagocitosis , Transducción de Señal , Receptor Toll-Like 4 , Femenino , Humanos , Receptor Toll-Like 4/metabolismo , Hemo/metabolismo , Neoplasias Endometriales/inmunología , Neoplasias Endometriales/metabolismo , Interferón Tipo I/metabolismo , Antígenos CD36/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Microambiente Tumoral/inmunología
14.
World J Gastrointest Endosc ; 16(8): 494-499, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39155994

RESUMEN

BACKGROUND: Heterotopic mesenteric ossification (HMO) is a clinically rare condition characterized by the formation of bone tissue in the mesentery. The worldwide reporting of such cases is limited to just over 70 instances in the medical literature. The etiology of HMO remains unclear, but the disease is possibly induced by mechanical trauma, ischemia, or intra-left lower quadrant abdominal infection, leading to the differentiation of mesenchymal stem cells into osteoblasts. Here, we present a rare case of HMO that occurred in a 34-year-old male, who presented with left lower quadrant abdominal pain. CASE SUMMARY: We report the case of a 34-year-old male patient who presented with left lower abdominal pain following trauma to the left lower abdomen. He subsequently underwent surgical treatment, and the postoperative pathological diagnosis was HMO. CONCLUSION: We believe that although there is limited literature and research on HMO, when patients with a history of trauma or surgery to the left lower abdomen present with corresponding imaging findings, clinicians should be vigilant in distinguishing this condition and promptly selecting appropriate diagnostic and therapeutic interventions.

15.
Nature ; 632(8027): 1032-1037, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39198671

RESUMEN

Superconductivity in a highly correlated kagome system has been theoretically proposed for years (refs. 1-5), yet the experimental realization is hard to achieve6,7. The recently discovered vanadium-based kagome materials8, which exhibit both superconductivity9-11 and charge-density-wave orders12-14, are nonmagnetic8,9 and weakly correlated15,16. Thus these materials are unlikely to host the exotic superconductivity theoretically proposed. Here we report the discovery of a chromium-based kagome metal, CsCr3Sb5, which is contrastingly featured with strong electron correlations, frustrated magnetism and characteristic flat bands close to the Fermi level. Under ambient pressure, this kagome metal undergoes a concurrent structural and magnetic phase transition at 55 K, with a stripe-like 4a0 structural modulation. At high pressure, the phase transition evolves into two transitions, possibly associated with charge-density-wave and antiferromagnetic spin-density-wave orderings. These density-wave-like orders are gradually suppressed with pressure and, remarkably, a superconducting dome emerges at 3.65-8.0 GPa. The maximum of the superconducting transition temperature, Tcmax = 6.4 K, appears when the density-wave-like orders are completely suppressed at 4.2 GPa, and the normal state exhibits a non-Fermi-liquid behaviour, reminiscent of unconventional superconductivity and quantum criticality in iron-based superconductors17,18. Our work offers an unprecedented platform for investigating superconductivity in correlated kagome systems.

16.
Heliyon ; 10(15): e35549, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39170171

RESUMEN

Background: Cancer stem cells (CSCs) are pivotal in tumor resistance to chemotherapy and gastric cancer's rapid proliferation and metastasis. We aimed to explore the CSCs-related genes in gastric cancer epithelial cells. Methods: The mRNA expression profile and single-cell sequencing data of gastric cancer were downloaded from the public database. Results: We identified WDR72 as a CSCs-related gene in gastric cancer epithelial cells. WDR72 was highly expressed in gastric cancer tissues, and high expression of WDR72 was associated with inferior prognosis of patients. WDR72 expression had a significant negative correlation with the infiltration of CD8 + T cells and activated memory CD4 + T cells. PD-L1 expression was significantly reduced in gastric cancer patients with high WDR72 expression. WDR72 was correlated with IC50 of multiple small-molecule drugs. Conclusion: We identified a novel CSCs-related gene in gastric cancer epithelial cells, WDR72, which was highly expressed in patients with high stemness scores.

17.
J Mol Biol ; 436(20): 168750, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39173734

RESUMEN

The final step in the de novo synthesis of cytidine 5'-triphosphate (CTP) is catalyzed by CTP synthase (CTPS), which can form cytoophidia in all three domains of life. Recently, we have discovered that CTPS binds to ribonucleotides (NTPs) to form filaments, and have successfully resolved the structures of Drosophila melanogaster CTPS bound with NTPs. Previous biochemical studies have shown that CTPS can bind to deoxyribonucleotides (dNTPs) to produce 2'-deoxycytidine-5'-triphosphate (dCTP). However, the structural basis of CTPS binding to dNTPs is still unclear. In this study, we find that Drosophila CTPS can also form filaments with dNTPs. Using cryo-electron microscopy, we are able to resolve the structure of Drosophila melanogaster CTPS bound to dNTPs with a resolution of up to 2.7 Å. By combining these structural findings with biochemical analysis, we compare the binding and reaction characteristics of NTPs and dNTPs with CTPS. Our results indicate that the same enzyme can act bifunctionally as CTP/dCTP synthase in vitro, and provide a structural basis for these activities.


Asunto(s)
Ligasas de Carbono-Nitrógeno , Microscopía por Crioelectrón , Citidina Trifosfato , Drosophila melanogaster , Animales , Ligasas de Carbono-Nitrógeno/química , Ligasas de Carbono-Nitrógeno/metabolismo , Ligasas de Carbono-Nitrógeno/genética , Citidina Trifosfato/metabolismo , Citidina Trifosfato/química , Drosophila melanogaster/enzimología , Modelos Moleculares , Unión Proteica , Conformación Proteica , Nucleótidos de Desoxicitosina/metabolismo , Nucleótidos de Desoxicitosina/química
18.
Eur Spine J ; 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39095489

RESUMEN

OBJECTIVE: This study aimed to distinguish tuberculous spondylodiscitis (TS) from pyogenic spondylodiscitis (PS) based on laboratory, magnetic resonance imaging (MRI) and computed tomography (CT) findings. Further, a novel diagnostic model for differential diagnosis was developed. METHODS: We obtained MRI, CT and laboratory data from TS and PS patients. Predictive models were built using binary logistic regression analysis. The receiver operating characteristic curve was analyzed. Both internal and external validation was performed. RESULTS: A total of 81 patients with PS (n = 46) or TS (n = 35) were enrolled. All patients had etiological evidence from the focal lesion. Disc signal or height preservation, skip lesion or multi segment (involved segments ≥ 3) involvement, paravertebral calcification, massive sequestra formation, subligamentous bone destruction, bone erosion with osteosclerotic margin, higher White Blood Cell Count (WBC) and positive result of tuberculosis infection T cell spot test (T-SPOT.TB) were more prevalent in the TS group. A diagnostic model was developed and included four predictors: WBC<7.265 * (10^9/L), skip lesion or involved segments ≥ 3, massive sequestra formation and subligamentous bone destruction. The model showed good sensitivity, specificity, and total accuracy (91.4%, 95.7%, and 93.8%, respectively); the area under the receiver operating characteristic curve (AUC) was 0.981, similar to the results of internal validation using bootstrap resampling (1000 replicates) and external validation set, indicating good clinical predictive ability. CONCLUSIONS: This study develop a good diagnostic model based on both CT and MRI, as well as laboratory findings, which may help clinicians distinguish between TS and PS.

19.
Mol Biol Rep ; 51(1): 891, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39110355

RESUMEN

BACKGROUND: Peptide transporter 1 (PepT1) transports bacterial oligopeptide products and induces inflammation of the bowel. Nutritional peptides compete for the binding of intestinal bacterial products to PepT1. We investigated the mechanism of short-peptide-based enteral nutrition (SPEN) on the damage to the gut caused by the bacterial oligopeptide product muramyl dipeptide (MDP), which is transported by PepT1. The gut-lung axis is a shared mucosal immune system, and immune responses and disorders can affect the gut-respiratory relationship. METHODS AND RESULTS: Sprague-Dawley rats were gavaged with solutions containing MDP, MDP + SPEN, MDP + intact-protein-based enteral nutrition (IPEN), glucose as a control, or glucose with GSK669 (a NOD2 antagonist). Inflammation, mitochondrial damage, autophagy, and apoptosis were explored to determine the role of the PepT1-nucleotide-binding oligomerization domain-containing protein 2 (NOD2)-beclin-1 signaling pathway in the small intestinal mucosa. MDP and proinflammatory factors of lung tissue were explored to determine that MDP can migrate to lung tissue and cause inflammation. Induction of proinflammatory cell accumulation and intestinal damage in MDP gavage rats was associated with increased NOD2 and Beclin-1 mRNA expression. IL-6 and TNF-α expression and apoptosis were increased, and mitochondrial damage was severe, as indicated by increased mtDNA in the MDP group compared with controls. MDP levels and expression of proinflammatory factors in lung tissue increased in the MDP group compared with the control group. SPEN, but not IPEN, eliminated these impacts. CONCLUSIONS: Gavage of MDP to rats resulted in damage to the gut-lung axis. SPEN reverses the adverse effects of MDP. The PepT1-NOD2-beclin-1 pathway plays a role in small intestinal inflammation, mitochondrial damage, autophagy, and apoptosis.


Asunto(s)
Acetilmuramil-Alanil-Isoglutamina , Beclina-1 , Nutrición Enteral , Lesión Pulmonar , Proteína Adaptadora de Señalización NOD2 , Transportador de Péptidos 1 , Ratas Sprague-Dawley , Transducción de Señal , Animales , Transportador de Péptidos 1/metabolismo , Transportador de Péptidos 1/genética , Ratas , Beclina-1/metabolismo , Beclina-1/genética , Proteína Adaptadora de Señalización NOD2/metabolismo , Proteína Adaptadora de Señalización NOD2/genética , Transducción de Señal/efectos de los fármacos , Lesión Pulmonar/metabolismo , Masculino , Acetilmuramil-Alanil-Isoglutamina/farmacología , Nutrición Enteral/métodos , Apoptosis/efectos de los fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Autofagia/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Pulmón/efectos de los fármacos , Inflamación/metabolismo
20.
JACC Cardiovasc Interv ; 17(16): 1874-1886, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39115479

RESUMEN

BACKGROUND: The index of microcirculatory resistance is a reliable measure for evaluating coronary microvasculature, but its prognostic value in patients with non-ST-segment elevation myocardial infarction (NSTEMI) remains unclear. OBJECTIVES: This study aimed to evaluate the prognostic impact of postpercutaneous coronary intervention (PCI) angiography-derived index of microcirculatory resistance (angio-IMR) in patients with NSTEMI. METHODS: The culprit vessel's angio-IMR was measured after PCI in 2,212 NSTEMI patients at 3 sites. The primary endpoint was 2-year major adverse cardiac events (MACEs), defined as a composite of cardiac death, readmission for heart failure, myocardial reinfarction, and target vessel revascularization. RESULTS: The mean post-PCI angio-IMR was 20.63 ± 4.17 in NSTEMI patients. A total of 206 patients were categorized as the high post-PCI angio-IMR group according to maximally selected log-rank statistics. Patients with angio-IMR >25 showed a higher rate of MACEs than those with angio-IMR ≤25 (32.52% vs 9.37%; P < 0.001). Post-PCI angio-IMR >25 was an independent predictor of MACEs (HR: 4.230; 95% CI: 3.151-5.679; P < 0.001) and showed incremental prognostic value compared with conventional risk factors (AUC: 0.774 vs 0.716; P < 0.001; net reclassification index: 0.317; P < 0.001; integrated discrimination improvement: 0.075; P < 0.001). CONCLUSIONS: In patients undergoing PCI for NSTEMI, an increased post-PCI angio-IMR is associated with a higher risk of MACEs. The addition of post-PCI angio-IMR into conventional risk factors significantly improves the ability to reclassify patients and estimate the risk of MACEs. (Angiograph-Derived Index of Microcirculatory Resistance in Patients With Acute Myocardial Infarction; NCT05696379).


Asunto(s)
Angiografía Coronaria , Circulación Coronaria , Microcirculación , Infarto del Miocardio sin Elevación del ST , Intervención Coronaria Percutánea , Valor Predictivo de las Pruebas , Resistencia Vascular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Infarto del Miocardio sin Elevación del ST/diagnóstico por imagen , Infarto del Miocardio sin Elevación del ST/terapia , Infarto del Miocardio sin Elevación del ST/fisiopatología , Infarto del Miocardio sin Elevación del ST/mortalidad , Intervención Coronaria Percutánea/efectos adversos , Factores de Riesgo , Resultado del Tratamiento , Medición de Riesgo , Factores de Tiempo , Recurrencia , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Readmisión del Paciente , China
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA