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1.
Proc Natl Acad Sci U S A ; 121(32): e2314087121, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39083421

RESUMEN

Invasive fungal diseases are a major threat to human health, resulting in more than 1.5 million annual deaths worldwide. The arsenal of antifungal therapeutics remains limited and is in dire need of drugs that target additional biosynthetic pathways that are absent from humans. One such pathway involves the biosynthesis of trehalose. Trehalose is a disaccharide that is required for pathogenic fungi to survive in their human hosts. In the first step of trehalose biosynthesis, trehalose-6-phosphate synthase (Tps1) converts UDP-glucose and glucose-6-phosphate to trehalose-6-phosphate. Here, we report the structures of full-length Cryptococcus neoformans Tps1 (CnTps1) in unliganded form and in complex with uridine diphosphate and glucose-6-phosphate. Comparison of these two structures reveals significant movement toward the catalytic pocket by the N terminus upon ligand binding and identifies residues required for substrate binding, as well as residues that stabilize the tetramer. Intriguingly, an intrinsically disordered domain (IDD), which is conserved among Cryptococcal species and closely related basidiomycetes, extends from each subunit of the tetramer into the "solvent" but is not visible in density maps. We determined that the IDD is not required for C. neoformans Tps1-dependent thermotolerance and osmotic stress survival. Studies with UDP-galactose highlight the exquisite substrate specificity of CnTps1. In toto, these studies expand our knowledge of trehalose biosynthesis in Cryptococcus and highlight the potential of developing antifungal therapeutics that disrupt the synthesis of this disaccharide or the formation of a functional tetramer and the use of cryo-EM in the structural characterization of CnTps1-ligand/drug complexes.


Asunto(s)
Antifúngicos , Cryptococcus neoformans , Glucosiltransferasas , Trehalosa , Cryptococcus neoformans/enzimología , Cryptococcus neoformans/metabolismo , Cryptococcus neoformans/genética , Glucosiltransferasas/metabolismo , Glucosiltransferasas/genética , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/metabolismo , Trehalosa/metabolismo , Trehalosa/análogos & derivados , Trehalosa/biosíntesis , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Modelos Moleculares , Humanos , Dominio Catalítico , Cristalografía por Rayos X
2.
Nano Lett ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856668

RESUMEN

Cell membrane-based nanovesicles (CMNVs) play pivotal roles in biomolecular transportation in living organisms and appear as attractive bioinformed nanomaterials for theranostic applications. However, the current surface-engineering technologies are limited in flexibility and orthogonality, making it challenging to simultaneously display multiple different ligands on the CMNV surface in a precisely controlled manner. Here, we developed a DNA scaffold-programmed approach to orthogonally engineer CMNVs with versatile ligands. The designed DNA scaffolds can rapidly anchor onto the CMNV surface, and their unique sequences and hybridized properties enable independent control of the loading of multiple different types of biomolecules on the CMNVs. As a result, the orthogonal engineering of CMNVs with a renal targeted peptide and a therapeutic protein at controlled ratios demonstrated an enhanced renal targeting and repair potential in vivo. This study highlights that a DNA scaffold-programmed platform can provide a potent means for orthogonal and flexible surface engineering of CMNVs for diverse therapeutic purposes.

3.
Mol Carcinog ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39016629

RESUMEN

Hepatocellular carcinoma (HCC) is a common malignant tumor. Histone lactylation, a novel epigenetic modification, plays a crucial role in various cancers. However, the functional role and underlying mechanism of histone lactylation in HCC progression have not yet been investigated. Histone lactylation levels in HCC tissues and cells were assessed using a densitometric kit and western blot analysis. The role of histone lactylation in cell malignant phenotypes was determined through functional assays in vitro, and a xenograft tumor model was established to verify the function of histone lactylation in vivo. ChIP assay was performed to explore the interaction between histone lactylation and endothelial cell-specific molecule 1 (ESM1). Additionally, gain-and-loss-of-function assays were conducted to investigate the regulatory role of ESM1 in HCC pathogenesis. Histone lactylation levels were increased in HCC tissues and cells, and H3K9 lactylation (H3K9la) and H3K56 lactylation (H3K56la) were identified as the histone modification sites. We observed that H3K9la and H3K56la caused abnormal histone lactylation and were associated with poor prognosis. Functionally, histone lactylation was found to promote HCC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) process in vitro. However, histone lactylation inhibition with 2-deoxy-d-glucose (2-DG) reduced the malignant phenotypes of HCC cells. In vivo, 2-DG treatment reduced tumor growth and metastasis in the HCC mouse model. Mechanistically, it was revealed that histone lactylation activated ESM1 transcription in HCC cells. ESM1 was expressed at a high level in HCC and exerted a carcinogenic role. Histone lactylation facilitates cell malignant phenotypes, tumor growth, and metastasis by upregulating ESM1 expression in HCC, which reveals the downstream molecular mechanism of histone lactylation and might provide a novel therapeutic target for HCC therapy.

4.
Insect Mol Biol ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709468

RESUMEN

Cordyceps cicadae (Hypocreales: Cordycipitaceae) is a renowned entomopathogenic fungus used as herbal medicine in China. However, wild C. cicadae resources have been threatened by heavy harvesting. We hypothesised that Bombyx mori L. (Lepidoptera: Bombycidae) could be a new alternative to cultivate C. cicadae due to the low cost of rearing. Bacterial communities are crucial for the formation of Cordyceps and for promoting the production of metabolites. To better understand the bacterial community structure associated with Cordyceps, three Claviciptaceae fungi were used to explore the pathogenicity of the silkworms. Here, fifth-instar silkworms were infected with C. cicadae, Cordyceps cateniannulata (Hypocreales: Cordycipitaceae) and Beauveria bassiana (Hypocreales: Cordycipitaceae). Subsequently, we applied high-throughput sequencing to explore the composition of bacterial communities in silkworms. Our results showed that all three fungi were highly pathogenic to silkworms, which suggests that silkworms have the potential to cultivate Cordyceps. After fungal infection, the diversity of bacterial communities in silkworms decreased significantly, and the abundance of Staphylococcus increased in mummified larvae, which may play a role in the death process when the host suffers infection by entomopathogenic fungi. Furthermore, there were high similarities in the bacterial community composition and function in the C. cicadae and C. cateniannulata infected samples, and the phylogenetic analysis suggested that these similarities may be related to the fungal phylogenetic relationship. Our findings reveal that infection with different entomopathogenic fungi affects the composition and function of bacterial communities in silkworms and that the bacterial species associated with Cordyceps are primarily host dependent, while fungal infection affects bacterial abundance.

5.
Neurochem Res ; 49(8): 2131-2147, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38822984

RESUMEN

BACKGROUND: Sepsis-associated encephalopathy (SAE) develops in 30-70% of hospitalized patients with sepsis. In intensive care units (ICUs), propofol is often administered to ensure an appropriate level of sedation in mechanically ventilated patients. Ferroptosis is a newly identified mode of cellular death characterized by the peroxidation of membrane lipids and excessive iron. This study was conducted to explore the interplay between propofol, sepsis, and ferroptosis. METHODS: An acute systemic inflammatory model was constructed via the intraperitoneal administration of lipopolysaccharide (LPS). Nissl and Fluoro-Jade C (FJC) staining were employed to display neuronal damage and degeneration. Western blotting and immunofluorescence (IF) staining of Bax and Bcl-2 were used to confirm the neural apoptosis. QPCR of cytokines and DHE staining were used to indicate neuroinflammation. To validate ferroptosis, we assessed the content of malondialdehyde (MDA), GSH, and tissue iron, accompanied by transcription level of CHAC1, PTGS2 and GPX4. Additionally, we examined the content of acyl-CoA synthetase long-chain family member 4 (ACSL4), xCT (SLC7A11, solute carrier family 7 member 11), and glutathione peroxidase 4 (GPX4). The IF staining of Iba1-labeled microglia and GFAP-marked astrocytes were used to measure the gliosis. Erastin was pre-pretreated to confirm the anti-ferroptotic capability of propofol. ML385 was preconditioned to explore the role of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in propofol-repressed ferroptosis. RESULTS: Propofol dose-dependently inhibited the decrease of Nissl-positive neurons and the increase of FJC-stained neurons in septic hippocampus and cortex. Neural cytokines, oxidative stress, apoptosis and gliosis were reduced by propofol. Propofol repressed the level of MDA, iron, CHAC1, PTGS2, ACLS4 and restored the content of GSH, GPX4, xCT, Nrf2 and HO-1, thus inhibiting sepsis-induced ferroptosis. All protections from propofol could be reversed by eratsin and ML385 pretreatment. CONCLUSION: Propofol protected against sepsis-induced brain damage, neuroinflammation, neuronal apoptosis and gliosis through the activation of the Nrf2/HO-1 axis to combat ferroptosis.


Asunto(s)
Ferroptosis , Factor 2 Relacionado con NF-E2 , Propofol , Ferroptosis/efectos de los fármacos , Ferroptosis/fisiología , Propofol/farmacología , Propofol/uso terapéutico , Factor 2 Relacionado con NF-E2/metabolismo , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Sepsis/metabolismo , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Lipopolisacáridos , Encefalopatía Asociada a la Sepsis/metabolismo , Encefalopatía Asociada a la Sepsis/tratamiento farmacológico , Encefalopatía Asociada a la Sepsis/prevención & control , Hemo-Oxigenasa 1/metabolismo , Hemo Oxigenasa (Desciclizante)/metabolismo , Proteínas de la Membrana/metabolismo , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/tratamiento farmacológico , Coenzima A Ligasas , Sistema de Transporte de Aminoácidos y+
6.
Langmuir ; 40(1): 721-733, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38147650

RESUMEN

Porous electrodes with high specific surface areas have been commonly employed for alkaline water electrolysis. The gas bubbles generated in electrodes due to water electrolysis, however, can screen the reaction sites and hinder reactant transport, thereby deteriorating the performance of electrodes. Hence, an in-depth understanding of the behavior of bubbles in porous electrodes is of great importance. Nevertheless, since porous electrodes are opaque, direct observation of bubbles therein is still a challenge. In this work, we have successfully captured the behavior of bubbles in the pores at the side surfaces of nickel-based porous electrodes. Two types of porous electrodes are employed: the ones with straight pores along the gravitational direction and the ones with tortuous pores. In the porous electrodes with tortuous pores, the moving bubbles are prone to collide with the solid matrix, thereby leading to the accumulation of bubbles in the pores and hence bubble trapping. By contrast, in the porous electrodes with straight pores, bubbles are seldom trapped; and when two bubbles near the wall surfaces coalesce, the merged bubble can jump away from the wall surfaces, releasing more active surfaces for reaction. As a result, the porous electrodes with straight pores, although with lower specific surface areas, are superior to those with tortuous pores. The relationship among the pore structures of porous electrodes, bubble behavior, and electrode performance disclosed in this work provides deep insights into the design of porous electrodes.

7.
Anal Bioanal Chem ; 416(8): 1883-1906, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38367042

RESUMEN

In this paper, we establish an in situ visualization analysis method to image the spatial distribution of metabolites in different parts (sclerotium, coremium) and different microregions of Cordyceps cicadae (C. cicadae) to achieve the in situ visual characterization of tissues for a variety of metabolites such as nucleosides, amino acids, polysaccharides, organic acids, fatty acids, and so on. The study included LC-MS chemical composition identification, preparation of C. cicadae tissue sections, DEDI-MSI analysis, DESI combined with Q-TOF/MS to obtain high-resolution imaging of mass-to-charge ratio and space, imaging of C. cicadae in positive-negative ion mode with a spatial resolution of 100 µm, and localizing and identifying its chemical compositions based on its precise mass. A total of 62 compounds were identified; nucleosides were mainly distributed in the coremium, L-threonine and DL-isoleucine, and other essential amino acids; peptides were mainly distributed in the sclerotium of C. cicadae; and the rest of the amino acids did not have a clear pattern; sugars and sugar alcohols were mainly distributed in the coremium of C. cicadae; organic acids and fatty acids were distributed in the nucleus of C. cicadae more than in the sclerotium, and the mass spectrometry imaging method is established in the research. The mass spectrometry imaging method established in this study is simple and fast and can visualize and analyse the spatial distribution of metabolites of C. cicadae, which is of great significance in characterizing the metabolic network of C. cicadae, and provides support for the quality evaluation of C. cicadae and the study of the temporal and spatial metabolic network of chemical compounds.


Asunto(s)
Cordyceps , Distribución Tisular , Espectrometría de Masas , Cordyceps/química , Cordyceps/metabolismo , Nucleósidos/química , Ácidos Grasos/metabolismo , Aminoácidos/metabolismo , Espectrometría de Masa por Ionización de Electrospray/métodos
8.
Artículo en Inglés | MEDLINE | ID: mdl-38884921

RESUMEN

BACKGROUND: Achieving full revascularization via percutaneous coronary intervention (PCI) may enhance the prognosis of individuals diagnosed with acute coronary syndrome (ACS) and multivessel coronary disease (MVD). The present work focused on investigating whether PCI should be performed during staged or index procedures for non-culprit lesions. METHODS: Electronic databases, such as PubMed, EMBASE, the Cochrane Library, and Web of Science, were systematically explored to locate studies contrasting immediate revascularization with staged complete revascularization for patients who experienced ACS and MVD without cardiac shock. The outcome measures comprised major adverse cardiovascular events (MACEs), all-cause mortality, cardiovascular mortality, myocardial infarction (MI), stroke, and unplanned ischemia-driven revascularization (UIDR). RESULTS: Nine randomized controlled trials involving 3550 patients, including 1780 who received immediate complete revascularization (ICR) and 1770 who received staged complete revascularization (SCR), were included in the analysis. The ICR group had lower MACEs (RR: 0.73, 95% CI: 0.61~0.87, P = 0.0004), MI (RR: 0.53, 95% CI: 0.37~0.77, P = 0.0008), and UIDR (RR: 0.64, 95% CI: 0.50~0.81, P = 0.0003) than did the SCR group. All-cause mortality, CVD incidence, and stroke incidence did not significantly differ between the two groups. According to our subgroup analyses based on the time window of the SCR, the ICR group had significantly fewer MACEs (RR: 0.70, 95% CI: 0.56~0.88, P = 0.003), MI (RR: 0.53, 95% CI: 0.37~0.77, P = 0.0002), and UIDR (RR: 0.56, 95% CI: 0.40~0.77, P = 0.0004) than did the subgroup of patients who were between discharge and 45 days. CONCLUSION: Compared with patients in the SCR group, patients in the ICR group had decreased MACEs, MI, and UIDR, especially between discharge and 45 days. All-cause mortality and CVD incidence were not significantly different between the two groups.

9.
J Sep Sci ; 47(15): e2400222, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39091177

RESUMEN

Drug-resistant bacterial infections pose a significant challenge in the field of bacterial disease treatment. Finding new antibacterial pathways and targets to combat drug-resistant bacteria is crucial. The bacterial quorum sensing (QS) system regulates the expression of bacterial virulence factors. Inhibiting bacterial QS and reducing bacterial virulence can achieve antibacterial therapeutic effects, making QS inhibition an effective strategy to control bacterial pathogenicity. This article mainly focused on the PqsA protein in the QS system of Pseudomonas aeruginosa. An affinity chromatography medium was developed using the SpyTag/SpyCatcher heteropeptide bond system. Berberine, which can interact with the PqsA target, was screened from Phellodendron amurense by affinity chromatography. We characterized its structure, verified its inhibitory activity on P. aeruginosa, and preliminarily analyzed its mechanism using molecular docking technology. This method can also be widely applied to the immobilization of various protein targets and the effective screening of active substances.


Asunto(s)
Antibacterianos , Cromatografía de Afinidad , Phellodendron , Pseudomonas aeruginosa , Percepción de Quorum , Percepción de Quorum/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/química , Phellodendron/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/aislamiento & purificación , Simulación del Acoplamiento Molecular , Evaluación Preclínica de Medicamentos , Pruebas de Sensibilidad Microbiana
10.
Int J Qual Health Care ; 36(1)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38334696

RESUMEN

Gait adaptability is essential for stroke survivors to achieve efficient and safe community ambulation. However, conventional treadmill rehabilitation is only a repetitive practice of leg movement. This study compared the effects of augmented reality treadmill-based gait adaptation training with regular treadmill programs for patients with stroke. Forty patients with stroke (n = 40) were randomly assigned to the gait adaptation training {n = 20, age: 49.85 [standard deviation (SD) 8.44] years; onset of stroke: 107.80 (SD 48.31) days} and regular training [n = 20, age: 50.75 (SD 8.05) years, onset of stroke: 111.60 (SD 49.62) days] groups. Both groups completed three sessions of training per week for 5 weeks (15 sessions). The primary outcomes were the 10-m walk test and success rate of obstacle avoidance, while secondary outcomes included the Berg balance scale, component timed-up-and-go, and fall rate in a 6-month follow-up period. Assessments were performed before and after the intervention. The paired t-test was applied to compare the differences within groups and independent sample t-test was performed to compare the differences between groups. The 10-m walk test, success rate of obstacle avoidance, Berg balance scale, and component timed-up-and-go all significantly improved in the both groups (P < .001). The success rate of obstacle avoidance [P = .02, 95% confidence interval (CI): -21.07, -1.64], Berg Balance Scale (P = .02, 95% CI: -8.03, -0.67), 'turning around time' (P = .04, 95% CI: 0.08, 2.81), 'stand-to-sit' (P = .03, 95% CI: 0.16, 2.41) and 'total time' (P = .048, 95% CI: 0.04, 10.32) improved significantly in gait adaptation training group after intervention, while the 10-m walk test (P = .09, 95% CI: -0.17, 0.01), timed 'sit-to-stand' (P = .09, 95% CI: -0.14, 2.04), and 'linear walking' (P = .09, 95% CI: -0.27, 3.25) in gait adaptation training group did not show statistical difference compared to the regular training group. Total fall rate during the follow-up period was statistically decreased in the gait adaptation training group (P = .045). Both interventions improved mobility outcomes, with augmented reality treadmill-based gait adaptation indicating greater improvement in obstacle avoidance, balance, turning, and stand-to-sit. Augmented reality treadmill-based gait adaptation training emerges as an effective and promising intervention for patients with stroke in early rehabilitation.


Asunto(s)
Realidad Aumentada , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Persona de Mediana Edad , Caminata , Accidente Cerebrovascular/complicaciones , Marcha , Resultado del Tratamiento
11.
Artículo en Inglés | MEDLINE | ID: mdl-38401075

RESUMEN

Objective: Acute gouty arthritis is the most common rheumatic diseases, and leads to a heavy clinical burden, thereby to explore the treatment effects of pachymaran on acute gouty arthritis and elucidate its mechanism are meaningful. Methods: Eighteen SPF C57BL/6 mice were randomly divided into three groups: the sham group, model group, and pachymaran group (200mg/kg), with 6 mice in each group. The acute gouty arthritis model of mice was established by injecting 0.025 mL sodium urate solution into the right ankle cavity of the mice. The pachymaran group was given 200mg/kg of pachymaran intragastrically, in the sham group and model group were given the same volume of normal saline, respectively, for 7 consecutive days. Blood samples were collected from the orbital venous plexus 1 h after the last administration, all mice were killed, and ankle tissue samples were collected. The pathological changes of mouse ankle synovial tissue were observed by HE staining. The expression levels of IL-1ß and IL-18 inflammatory factors in the serum of mice were determined by ELISA. The ultrastructure of the synovial tissue of the mouse ankle joint was observed by transmission electron microscope. The protein expression levels of NLRP3, ASC, IL-1ß, IL-18, GSDMD, and Caspase-1 in synovial tissue of mouse ankle were detected by Western blot assay. Mouse chondrocytes were cultured and divided into groups I, II, III, and IV. Group I was the control group without any drug intervention. The cells in groups II, III, and IV were stimulated with sodium urate solution (100µg/mL), and groups III and IV were intervened by pachymaran (200µg/mL), among which the NLRP3 agonist Nigericin sodium salt intervened group IV. The expression levels of NLRP3, IL-1ß, GSDMD, and Caspase-1 proteins were detected by Western blot assay, and the apoptosis rate was detected by flow cytometry. Results: Compared with the sham group, the pathological injury of mice ankle synovial tissue in the model group was significantly aggravated, as the membrane was incomplete, mitochondria were swollen, the ridge was unclear or even disappeared, and the pathological injury of mice ankle synovial tissue in the pachymaran group was significantly improved vs model group; the serum levels of IL-1ß and IL-18 were increased in model group vs sham group, and pachymaran decreased these index vs model group; Compared with the sham group, protein expression levels of NLRP3, ASC, IL-1ß, IL-18, GSDMD, and Caspase-1 were significant increased in model group, and pachymaran suppressed these proteins vs model group. The TEM results showed that in model group the wide swelling of mitochondria accompanied by disappearance of mitochondrial cristae vs sham group, and the mitochondrial ridge was slightly damaged, or the mitochondria were only swollen, and the ridge was still clearly visible in pachymaran group. In vitro experiments, Compared with group I, the protein expression levels of NLRP3, IL-1ß, GSDMD, Caspase-1, and the apoptosis rate of chondrocytes in group II were significantly increased. Compared with group II, the protein expression levels of NLRP3, IL-1ß, GSDMD, Caspase-1, and the apoptosis rate of chondrocytes in group III were significantly decreased. Compared with group III, the protein expression levels of NLRP3, IL-1ß, GSDMD, Caspase-1, and the apoptosis rate of chondrocytes in group IV were significantly increased. Conclusion: Pachymaran maintain the structural integrity of joints and alleviate the progression of acute gouty arthritis by inhibiting NLRP3 inflammasome activation and pyroptosis, pachymaran may be used and applied to clinical treatment.

12.
Phytother Res ; 38(8): 4114-4139, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39031847

RESUMEN

Traditional Chinese Medicine (TCM), as a unique medical model in China, has been shown to be effective in the treatment of many diseases. It has been proven that TCM can increase the pain threshold, increase the level of endorphins and enkephalins in the body, and reduce the body's response to adverse stimuli. In recent years, TCM scholars have made valuable explorations in the field of pain treatment, using methods such as internal and external application of TCM and acupuncture to carry out research on pain treatment and have achieved more satisfactory results. TCM treats pain in a variety of ways, and with the discovery of a variety of potential bioactive substances for pain treatment. With the new progress in the research of other TCM treatment methods for pain, TCM will have greater potential in the clinical application of pain.


Asunto(s)
Medicina Tradicional China , Manejo del Dolor , Dolor , Humanos , Medicina Tradicional China/métodos , Manejo del Dolor/métodos , Dolor/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/farmacología , Terapia por Acupuntura , Animales
13.
J Environ Manage ; 351: 119828, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38134506

RESUMEN

Urbanisation is a key aspect of land use change (LUC), and accurately modelling of urban LUC is crucial for sustainable development. Cellular automata (CA) are widely used in LUC research. However, previous studies have overlooked the significant temporal dependence and spatial heterogeneity associated with LUC. To address these gaps, this study proposes a novel model called KCLP-CA, which integrates k-means, a convolutional neural network (CNN), a long and short-term memory neural network (LSTM), and the popular patch-generation land use model (PLUS). Initially, k-means and CNN are utilised to address spatial heterogeneity, while LSTM tackles temporal dependence. The LSTM and land expansion analysis strategy (LEAS) models of PLUS are employed to obtain land use conversion probability maps. Finally, a simulation of land use dynamic change was conducted using a linear weighted fusion conversion probability map that accounts for random factors. To validate the KCLP-CA model, land use data collected from Hangzhou between 1995 and 2000 were employed. The results showed that the KCLP-CA model outperformed traditional methods, including artificial neural networks and random forest model, with the figure of merit (FoM) index increasing from 2.12% to 4.19%. Random forest analysis of drivers impacting LUC revealed that distance to water and road network density exerted the greatest influence on urban land development in Hangzhou. Incorporation of various policy planning factors affecting urban development yielded simulation results aligning more closely with reality, resulting in a FoM index increase of 1.64-1.76%. In summary, the model developed in this study combines the strengths of two sub models to deliver an accurate and effective simulation of future land use.


Asunto(s)
Autómata Celular , Redes Neurales de la Computación , Simulación por Computador , Desarrollo Sostenible , Urbanización
14.
Angew Chem Int Ed Engl ; : e202409588, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39060222

RESUMEN

The wrinkles are pervasive in ultrathin two-dimensional (2D) materials, but the regulation of wrinkles is rarely explored systematically. However, the regulation of wrinkles at nanometer scale is merely explored. Here, we employed a series of carboxylic acids (from formic acid to octanoic acid) to control the wrinkles of Zr-BTB (BTB = 1, 3, 5-(4-carboxylphenyl)-benzene) metal-organic framework (MOF) nanosheet. The wrinkles at the micrometer scale were observed with transmission electron microscopy. Furthermore, high-angle annular dark-field (HAADF) images showed lattice distortion in many nanoscale regions, which was precisely matched to the nano-wrinkles. With the changes of hydrophilicity/hydrophobicity, MOF-MOF and MOF-solvent interactions were synergistically regulated and wrinkles with different sizes were obtained, which was supported by HAADF, molecular dynamics and density functional theory calculation. Different wrinkle sizes resulted in different pore sizes between the Zr-BTB nanosheet interlayers, providing highly-oriented thin films and the successive optimization of kinetic diffusion pathways, proved by grazing-incidence wide-angle X-ray scattering and nitrogen adsorption. The most suitable wrinkle pore from Zr-BTB-C4 exhibited highly efficient chromatographic separation of the substituted benzene isomers. Our work provides a rational route for the modulation of nanoscale wrinkles and their stacked pores of MOF nanosheets and improves the separation abilities of MOFs.

16.
J Struct Biol X ; 10: 100104, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39044770

RESUMEN

Cryo-electron tomography (cryo-ET) combined with sub-tomogram averaging (STA) allows the determination of protein structures imaged within the native context of the cell at near-atomic resolution. Particle picking is an essential step in the cryo-ET/STA image analysis pipeline that consists in locating the position of proteins within crowded cellular tomograms so that they can be aligned and averaged in 3D to improve resolution. While extensive work in 2D particle picking has been done in the context of single-particle cryo-EM, comparatively fewer strategies have been proposed to pick particles from 3D tomograms, in part due to the challenges associated with working with noisy 3D volumes affected by the missing wedge. While strategies based on 3D template-matching and deep learning are commonly used, these methods are computationally expensive and require either an external template or manual labelling which can bias the results and limit their applicability. Here, we propose a size-based method to pick particles from tomograms that is fast, accurate, and does not require external templates or user provided labels. We compare the performance of our approach against a commonly used algorithm based on deep learning, crYOLO, and show that our method: i) has higher detection accuracy, ii) does not require user input for labeling or time-consuming training, and iii) runs efficiently on non-specialized CPU hardware. We demonstrate the effectiveness of our approach by automatically detecting particles from tomograms representing different types of samples and using these particles to determine the high-resolution structures of ribosomes imaged in vitro and in situ.

17.
Biol Imaging ; 4: e4, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38571546

RESUMEN

Cryo-electron microscopy (cryo-EM) is an imaging technique that allows the visualization of proteins and macromolecular complexes at near-atomic resolution. The low electron doses used to prevent radiation damage to the biological samples result in images where the power of noise is 100 times stronger than that of the signal. Accurate identification of proteins from these low signal-to-noise ratio (SNR) images is a critical task, as the detected positions serve as inputs for the downstream 3D structure determination process. Current methods either fail to identify all true positives or result in many false positives, especially when analyzing images from smaller-sized proteins that exhibit extremely low contrast, or require manual labeling that can take days to complete. Acknowledging the fact that accurate protein identification is dependent upon the visual interpretability of micrographs, we propose a framework that can perform denoising and detection in a joint manner and enable particle localization under extremely low SNR conditions using self-supervised denoising and particle identification from sparsely annotated data. We validate our approach on three challenging single-particle cryo-EM datasets and projection images from one cryo-electron tomography dataset with extremely low SNR, showing that it outperforms existing state-of-the-art methods used for cryo-EM image analysis by a significant margin. We also evaluate the performance of our algorithm under decreasing SNR conditions and show that our method is more robust to noise than competing methods.

18.
Medicine (Baltimore) ; 103(31): e39178, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093778

RESUMEN

This study aimed to examine the influence of diabetes on the left internal mammary artery (LIMA) and saphenous vein (SV) graft failure for 5-year follow-up. We enrolled 202 patients who underwent isolated off-pump coronary artery bypass grafting (CABG) surgery in 2014, angiographic follow-up occurred at 5 years after surgery. Angiographic outcomes in patients with or without diabetes were analyzed. Multivariate logistic regression analysis was used to identify independent predictors of graft dysfunction. A total of 66 (32.7%) patients had diabetes. Five-year rates of LIMA and SV graft failure were similar in patients with and without diabetes. In addition, in diabetics, the proportion of complete graft failure was significantly lower in the LIMA grafts (12/66, 18.2%) than in the SV grafts (57/133, 42.9%) (P = .001). In nondiabetic, the proportion of complete graft failure was also significantly lower in the LIMA grafts (28/136, 20.6%) than in the SV grafts (105/275, 38.2%) (P < .001). Multivariate logistic regression analysis showed that mean graft flow (MGF) was an independent predictor factor for LIMA (odds ratio = 1.186, 95% CI = 1.114-1.263, P < .001) and SV (odds ratio = 1.056, 95% CI = 1.035-1.077, P < .001) graft failure. Diabetes did not influence the patency of LIMA or SV grafts over a 5-year follow-up. LIMA grafts should be maximized in patients undergoing off-pump CABG surgery. Diabetes does not affect the patency of grafts CABG. Using angiography, our study proved that diabetes does not affect the patency of grafted vessels after CABG for 5 years.


Asunto(s)
Angiografía Coronaria , Puente de Arteria Coronaria Off-Pump , Arterias Mamarias , Grado de Desobstrucción Vascular , Humanos , Puente de Arteria Coronaria Off-Pump/métodos , Masculino , Femenino , Angiografía Coronaria/métodos , Persona de Mediana Edad , Anciano , Arterias Mamarias/trasplante , Arterias Mamarias/diagnóstico por imagen , Vena Safena/trasplante , Vena Safena/diagnóstico por imagen , Diabetes Mellitus/epidemiología , Oclusión de Injerto Vascular/epidemiología , Oclusión de Injerto Vascular/diagnóstico por imagen , Oclusión de Injerto Vascular/etiología , Estudios Retrospectivos , Enfermedad de la Arteria Coronaria/cirugía , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estudios de Seguimiento
19.
Drug Des Devel Ther ; 18: 1349-1368, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38681208

RESUMEN

Background: Sepsis is recognized as a multiorgan and systemic damage caused by dysregulated host response to infection. Its acute systemic inflammatory response highly resembles that of lipopolysaccharide (LPS)-induced endotoxemia. Propofol and dexmedetomidine are two commonly used sedatives for mechanical ventilation in critically ill patients and have been reported to alleviate cognitive impairment in many diseases. In this study, we aimed to explore and compare the effects of propofol and dexmedetomidine on the encephalopathy induced by endotoxemia and to investigate whether ferroptosis is involved, finally providing experimental evidence for multi-drug combination in septic sedation. Methods: A total of 218 C57BL/6J male mice (20-25 g, 6-8 weeks) were used. Morris water maze (MWM) tests were performed to evaluate whether propofol and dexmedetomidine attenuated LPS-induced cognitive deficits. Brain injury was evaluated using Nissl and Fluoro-Jade C (FJC) staining. Neuroinflammation was assessed by dihydroethidium (DHE) and DCFH-DA staining and by measuring the levels of three cytokines. The number of Iba1+ and GFAP+ cells was used to detect the activation of microglia and astrocytes. To explore the involvement of ferroptosis, the levels of ptgs2 and chac1; the content of iron, malondialdehyde (MDA), and glutathione (GSH); and the expression of ferroptosis-related proteins were investigated. Conclusion: The single use of propofol and dexmedetomidine mitigated LPS-induced cognitive impairment, while the combination showed poor performance. In alleviating endotoxemic neural loss and degeneration, the united sedative group exhibited the most potent capability. Both propofol and dexmedetomidine inhibited neuroinflammation, while propofol's effect was slightly weaker. All sedative groups reduced the neural apoptosis, inhibited the activation of microglia and astrocytes, and relieved neurologic ferroptosis. The combined group was most prominent in combating genetic and biochemical alterations of ferroptosis. Fpn1 may be at the core of endotoxemia-related ferroptosis activation.


Asunto(s)
Dexmedetomidina , Endotoxemia , Ferroptosis , Lipopolisacáridos , Ratones Endogámicos C57BL , Propofol , Dexmedetomidina/farmacología , Animales , Propofol/farmacología , Ferroptosis/efectos de los fármacos , Ratones , Masculino , Endotoxemia/tratamiento farmacológico , Endotoxemia/metabolismo , Endotoxemia/inducido químicamente , Lipopolisacáridos/farmacología , Relación Dosis-Respuesta a Droga , Encefalopatías/tratamiento farmacológico , Encefalopatías/metabolismo , Encefalopatías/patología , Hipnóticos y Sedantes/farmacología
20.
Front Public Health ; 12: 1375379, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38737864

RESUMEN

Background: Inflammation and liver function are associated with cognitive decline and dementia. Little is known about the serum albumin-to-globulin ratio on cognitive function. Objective: The objective of this study was to investigate the association between albumin-to-globulin ratio and cognitive function among the American older people. Methods: The public data available on the US National Health and Nutrition Examination Survey (NHANES) from 2011 to 2014 was used for this cross-sectional study. Participants aged ≥60 years completed the cognitive function assessments, including word learning and recall modules from the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), the animal fluency (AF) test, and the digit symbol substitution test (DSST). A composite cognition score was calculated to evaluate global cognition. The univariate and multivariate linear regression analysis, curve fitting, a threshold effect, along with a subgroup analysis and interaction tests were conducted. Results: Serum albumin-to-globulin ratio (per 0.1 unit) was positively associated DSST score (ß = 0.36, 95% CI: 0.21, 0.51), AF score (ß = 0.1, 95% CI: 0.04, 0.16) and global cognition score (ß = 0.05, 95% CI: 0.02, 0.07), after being fully adjusted, while albumin-to-globulin ratio was not related to CERAD score (ß = 0.05, 95% CI: -0.02, 0.12). A non-linear was observed in the dose-response relationship between albumin-to-globulin ratio and global cognition (P for non-linearity < 0.001). The subgroup analysis was overall stable, yet the interaction test was significant for age on global cognition (P for interaction = 0.036). Conclusion: The findings of this cross-sectional study suggested a positive and non-linear association between albumin-to-globulin ratio and cognitive function in the American older people. Maintaining albumin-to-globulin ratio with an appropriate range may be one of the therapeutic strategies to limit the progression of cognitive decline for the older people.


Asunto(s)
Cognición , Encuestas Nutricionales , Albúmina Sérica , Seroglobulinas , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cognición/fisiología , Disfunción Cognitiva/sangre , Estudios Transversales , Albúmina Sérica/análisis , Seroglobulinas/análisis , Estados Unidos
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