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1.
Proc Natl Acad Sci U S A ; 121(18): e2319751121, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38662548

RESUMEN

Defect engineering has been widely applied in semiconductors to improve photocatalytic properties by altering the surface structures. This study is about the transformation of inactive WO3 nanosheets to a highly effective CO2-to-CH4 conversion photocatalyst by introducing surface-ordered defects in abundance. The nonstoichiometric WO3-x samples were examined by using aberration-corrected electron microscopy. Results unveil abundant surface-ordered terminations derived from the periodic {013} stacking faults with a defect density of 20.2%. The {002} surface-ordered line defects are the active sites for fixation CO2, transforming the inactive WO3 nanosheets into a highly active catalyst (CH4: O2 = 8.2: 16.7 µmol h-1). We believe that the formation of the W-O-C-W-O species is a critical step in the catalytic pathways. This work provides an atomic-level comprehension of the structural defects of catalysts for activating small molecules.

2.
EMBO J ; 40(11): e107226, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33932049

RESUMEN

Malaria parasite egress from host erythrocytes (RBCs) is regulated by discharge of a parasite serine protease called SUB1 into the parasitophorous vacuole (PV). There, SUB1 activates a PV-resident cysteine protease called SERA6, enabling host RBC rupture through SERA6-mediated degradation of the RBC cytoskeleton protein ß-spectrin. Here, we show that the activation of Plasmodium falciparum SERA6 involves a second, autocatalytic step that is triggered by SUB1 cleavage. Unexpectedly, autoproteolytic maturation of SERA6 requires interaction in multimolecular complexes with a distinct PV-located protein cofactor, MSA180, that is itself a SUB1 substrate. Genetic ablation of MSA180 mimics SERA6 disruption, producing a fatal block in ß-spectrin cleavage and RBC rupture. Drug-like inhibitors of SERA6 autoprocessing similarly prevent ß-spectrin cleavage and egress in both P. falciparum and the emerging zoonotic pathogen P. knowlesi. Our results elucidate the egress pathway and identify SERA6 as a target for a new class of antimalarial drugs designed to prevent disease progression.


Asunto(s)
Antimaláricos/farmacología , Proteasas de Cisteína/metabolismo , Plasmodium falciparum/metabolismo , Inhibidores de Proteasas/farmacología , Proteínas Protozoarias/metabolismo , Células Cultivadas , Eritrocitos/metabolismo , Eritrocitos/parasitología , Humanos , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/patogenicidad , Proteolisis , Proteínas Protozoarias/antagonistas & inhibidores , Serina Proteasas/metabolismo , Espectrina/metabolismo
3.
Biochem Biophys Res Commun ; 718: 149981, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38735134

RESUMEN

In animal cells, vacuoles are absent, but can be induced by diseases and drugs. While phosphoinositides are critical for membrane trafficking, their role in the formation of these vacuoles remains unclear. The immunosuppressive KRP203/Mocravimod, which antagonizes sphingosine-1-phosphate receptors, has been identified as having novel multimodal activity against phosphoinositide kinases. However, the impact of this novel KRP203 activity is unknown. Here, we show that KRP203 disrupts the spatial organization of phosphoinositides and induces extensive vacuolization in tumor cells and immortalized fibroblasts. The KRP203-induced vacuoles are primarily from endosomes, and augmented by inhibition of PIKFYVE and VPS34. Conversely, overexpression of PTEN decreased KRP203-induced vacuole formation. Furthermore, V-ATPase inhibition completely blunted KRP203-induced vacuolization, pointing to a critical requirement of the endosomal maturation process. Importantly, nearly a half of KRP203-induced vacuoles are significantly decorated with PI4P, a phosphoinositide typically enriched at the plasma membrane and Golgi. These results suggest a model that noncanonical spatial reorganization of phosphoinositides by KRP203 alters the endosomal maturation process, leading to vacuolization. Taken together, this study reveals a previously unrecognized bioactivity of KRP203 as a vacuole-inducing agent and its unique mechanism of phosphoinositide modulation, providing a new insight of phosphoinositide regulation into vacuolization-associated diseases and their molecular pathologies.


Asunto(s)
Endosomas , Fosfohidrolasa PTEN , Fosfatidilinositoles , Vacuolas , Vacuolas/metabolismo , Vacuolas/efectos de los fármacos , Endosomas/metabolismo , Endosomas/efectos de los fármacos , Humanos , Fosfatidilinositoles/metabolismo , Animales , Fosfohidrolasa PTEN/metabolismo , Fosfohidrolasa PTEN/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas Clase III/metabolismo , Fosfatidilinositol 3-Quinasas Clase III/genética , Ratones , Morfolinas/farmacología , ATPasas de Translocación de Protón Vacuolares/metabolismo , ATPasas de Translocación de Protón Vacuolares/antagonistas & inhibidores , ATPasas de Translocación de Protón Vacuolares/genética , Citoplasma/metabolismo , Células HeLa , Aminopiridinas , Compuestos Heterocíclicos con 3 Anillos
4.
Brief Bioinform ; 23(1)2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-34472587

RESUMEN

Chemosensitivity assays are commonly used for preclinical drug discovery and clinical trial optimization. However, data from independent assays are often discordant, largely attributed to uncharacterized variation in the experimental materials and protocols. We report here the launching of Minimal Information for Chemosensitivity Assays (MICHA), accessed via https://micha-protocol.org. Distinguished from existing efforts that are often lacking support from data integration tools, MICHA can automatically extract publicly available information to facilitate the assay annotation including: 1) compounds, 2) samples, 3) reagents and 4) data processing methods. For example, MICHA provides an integrative web server and database to obtain compound annotation including chemical structures, targets and disease indications. In addition, the annotation of cell line samples, assay protocols and literature references can be greatly eased by retrieving manually curated catalogues. Once the annotation is complete, MICHA can export a report that conforms to the FAIR principle (Findable, Accessible, Interoperable and Reusable) of drug screening studies. To consolidate the utility of MICHA, we provide FAIRified protocols from five major cancer drug screening studies as well as six recently conducted COVID-19 studies. With the MICHA web server and database, we envisage a wider adoption of a community-driven effort to improve the open access of drug sensitivity assays.

5.
FASEB J ; 37(12): e23292, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37971407

RESUMEN

Immunotoxins (ITs) target cancer cells via antibody binding to surface antigens followed by internalization and toxin-mediated inhibition of protein synthesis. The fate of cells responding to IT treatment depends on the amount and stability of specific pro-apoptotic and pro-survival proteins. When treated with a pseudomonas exotoxin-based immunotoxin (HB21PE40), the triple-negative breast cancer (TNBC) cell line MDA-MB-468 displayed a notable resistance to toxin-mediated killing compared to the epidermoid carcinoma cell line, A431, despite succumbing to the same level of protein synthesis inhibition. In a combination screen of ~1912 clinically relevant and mechanistically annotated compounds, we identified several agents that greatly enhanced IT-mediated killing of MDA-MB-468 cells while exhibiting only a modest enhancement for A431 cells. Of interest, two Smac mimetics, birinapant and SM164, exhibited this kind of differential enhancement. To investigate the basis for this, we probed cells for the presence of inhibitor of apoptosis (IAP) proteins and monitored their stability after the addition of immunotoxin. We found that high levels of IAPs inhibited immunotoxin-mediated cell death. Further, TNFα levels were not relevant for the combination's efficacy. In tumor xenograft studies, combinations of immunotoxin and birinapant caused complete regressions in MDA-MB-468tumor-bearing mice but not in mice with A431 tumors. We propose that IAPs constitute a barrier to immunotoxin efficacy which can be overcome with combination treatments that include Smac mimetics.


Asunto(s)
Inmunotoxinas , Neoplasias , Humanos , Animales , Ratones , Proteínas Inhibidoras de la Apoptosis/metabolismo , Inmunotoxinas/farmacología , Línea Celular Tumoral , Dipéptidos/farmacología , Apoptosis
6.
BMC Neurol ; 24(1): 98, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500057

RESUMEN

BACKGROUND: Complex interactions between the immune system and the brain may affect neural development, survival, and function, with etiological and therapeutic implications for neurodegenerative diseases. However, previous studies investigating the association between immune inflammation and Alzheimer's disease (AD) have yielded inconsistent results. METHODS: We applied Mendelian randomization (MR) to examine the causal relationship between immune cell traits and AD risk using genetic variants as instrumental variables. MR is an epidemiological study design based on genetic information that reduces the effects of confounding and reverse causation. We analyzed the causal associations between 731 immune cell traits and AD risk based on publicly available genetic data. RESULTS: We observed that 5 immune cell traits conferred protection against AD, while 7 immune cell traits increased the risk of AD. These immune cell traits mainly involved T cell regulation, monocyte activation and B cell differentiation. Our findings suggest that immune regulation may influence the development of AD and provide new insights into potential targets for AD prevention and treatment. We also conducted various sensitivity analyses to test the validity and robustness of our results, which revealed no evidence of pleiotropy or heterogeneity. CONCLUSION: Our research shows that immune regulation is important for AD and provides new information on potential targets for AD prevention and treatment. However, this study has limitations, including the possibility of reverse causality, lack of validation in independent cohorts, and potential confounding by population stratification. Further research is needed to validate and amplify these results and to elucidate the potential mechanisms of the immune cell-AD association.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/genética , Análisis de la Aleatorización Mendeliana , Encéfalo , Causalidad , Inflamación , Estudio de Asociación del Genoma Completo
7.
J Chem Inf Model ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025788

RESUMEN

ADCK3 is a member of the UbiB family of atypical protein kinases in humans, with homologues in archaea, bacteria, and eukaryotes. In lieu of protein kinase activity, ADCK3 plays a role in the biosynthesis of coenzyme Q10 (CoQ10), and inactivating mutations can cause a CoQ10 deficiency and ataxia. However, the exact functions of ADCK3 are still unclear, and small-molecule inhibitors could be useful as chemical probes to elucidate its molecular mechanisms. In this study, we applied structure-based virtual screening (VS) to discover a novel chemical series of ADCK3 inhibitors. Through extensive structural analysis of the active-site residues, we developed a pharmacophore model and applied it to a large-scale VS. Out of ∼170,000 compounds virtually screened, 800 top-ranking candidate compounds were selected and tested in both ADCK3 and p38 biochemical assays for hit validation. In total, 129 compounds were confirmed as ADCK3 inhibitors, and among them, 114 compounds are selective against p38, which was used as a counter-target. Molecular dynamics (MD) simulations were then conducted to predict the binding modes of the most potent compounds within the ADCK3 active site. Through metadynamics analysis, we successfully detected the key amino acid residues that govern intermolecular interactions. The findings provided in this study can serve as a promising starting point for drug development.

8.
Acta Pharmacol Sin ; 45(6): 1130-1141, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38195693

RESUMEN

Hepatocellular carcinoma (HCC) is one of the most common malignancy, presenting a formidable challenge to the medical community owing to its intricate pathogenic mechanisms. Although current prevention, surveillance, early detection, diagnosis, and treatment have achieved some success in preventing HCC and controlling overall disease mortality, the imperative to explore novel treatment modalities for HCC remains increasingly urgent. Epigenetic modification has emerged as pivotal factors in the etiology of cancer. Among these, RNA N6-methyladenosine (m6A) modification stands out as one of the most prevalent, abundant, and evolutionarily conserved post-transcriptional alterations in eukaryotes. The literature underscores that the dynamic and reversible nature of m6A modifications orchestrates the intricate regulation of gene expression, thereby exerting a profound influence on cell destinies. Increasing evidence has substantiated conspicuous fluctuations in m6A modification levels throughout the progression of HCC. The deliberate modulation of m6A modification levels through molecular biology and pharmacological interventions has been demonstrated to exert a discernible impact on the pathogenesis of HCC. In this review, we elucidate the multifaceted biological functions of m6A modifications in HCC, and concurrently advancing novel therapeutic strategies for the management of this malignancy.


Asunto(s)
Adenosina , Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Animales , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , ARN/metabolismo , ARN/genética
9.
Acta Pharmacol Sin ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902501

RESUMEN

The impairment of blood-brain barrier (BBB) integrity is the pathological basis of hemorrhage transformation and vasogenic edema following thrombolysis and endovascular therapy. There is no approved drug in the clinic to reduce BBB damage after acute ischemic stroke (AIS). Glial growth factor 2 (GGF2), a recombinant version of neuregulin-1ß that can stimulates glial cell proliferation and differentiation, has been shown to alleviate free radical release from activated microglial cells. We previously found that activated microglia and proinflammatory factors could disrupt BBB after AIS. In this study we investigated the effects of GGF2 on AIS-induced BBB damage as well as the underlying mechanisms. Mouse middle cerebral artery occlusion model was established: mice received a 90-min ischemia and 22.5 h reperfusion (I/R), and were treated with GGF2 (2.5, 12.5, 50 ng/kg, i.v.) before the reperfusion. We showed that GGF2 treatment dose-dependently decreased I/R-induced BBB damage detected by Evans blue (EB) and immunoglobulin G (IgG) leakage, and tight junction protein occludin degradation. In addition, we found that GGF2 dose-dependently reversed AIS-induced upregulation of vesicular transcytosis increase, caveolin-1 (Cav-1) as well as downregulation of major facilitator superfamily domain containing 2a (Mfsd2a). Moreover, GGF2 decreased I/R-induced upregulation of PDZ and LIM domain protein 5 (Pdlim5), an adaptor protein that played an important role in BBB damage after AIS. In addition, GGF2 significantly alleviated I/R-induced reduction of YAP and TAZ, microglial cell activation and upregulation of inflammatory factors. Together, these results demonstrate that GGF2 treatment alleviates the I/R-compromised integrity of BBB by inhibiting Mfsd2a/Cav-1-mediated transcellular permeability and Pdlim5/YAP/TAZ-mediated paracellular permeability.

10.
BMC Pulm Med ; 24(1): 305, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943129

RESUMEN

OBJECTIVE: To compare the impact of telerehabilitation versus conventional rehabilitation on the recovery outcomes of patients with chronic respiratory disease (CRD). METHODS: The Cochrane Library, MEDLINE, Web of Science and Embase were searched to collect randomized controlled trials (RCTs) on telerehabilitation for the rehabilitation of patients with chronic respiratory system diseases since the establishment of the database to November 14, 2023. Two researchers independently screened the literature and extracted valid data according to the inclusion criteria. The quality assessment of included studies was conducted individually by using the RoB 2(Risk of Bias 2) tool, followed by meta-analysis using RevMan5.3 software. RESULTS: Based on inclusion and exclusion criteria, 21 RCTs were included, comprising 3030 participants, with 1509 in the telerehabilitation group and 1521 in the conventional rehabilitation group. Meta-analysis results indicated that compared to conventional rehabilitation, video conference-based telerehabilitation demonstrated significant improvements in short-term (≤ 6 months) outcomes, including 6-min walk distance (6MWD) (MD = 7.52, 95% CI: 2.09, 12.94), modified Medical Research Council Dyspnea Scale (mMRC) (MD = -0.29, 95% CI: -0.41, -0.18), COPD assessment test (CAT) (MD = -1.77, 95% CI: -3.52, -0.02), HADS (MD = -0.44, 95% CI: -0.86, -0.03), and St. George's Respiratory Questionnaire (SGRQ's) activity, impact, and symptom scores. In the long term (> 6 months), although improvements persisted in 6WMD [MD = 12.89, 95% CI (-0.37, 26.14)], mMRC [MD = -0.38, 95% CI (-0.56, -0.21)], CAT [MD = -1.39, 95% CI (-3.83, 1.05)], Hospital anxiety and depression scale (HADS) [MD = -0.34, 95% CI (-0.66, -0.03)], and SGRQ's Activity, Impact, and Symptom scores between intervention and control groups, statistically significant differences were observed only for mMRC and HADS. Without considering time factors, the intervention group exhibited some improvement in FEV1% predicted and the forced expiratory volume in the first one second (FEV1)/ forced vital capacity (FVC) (%) without statistical significance compared to the control group. CONCLUSION: Telerehabilitation therapy demonstrates short-term benefits in enhancing patients' daily activity capacity, improving respiratory function, and enhancing mental health status, thereby improving patients' quality of life. However, further high-quality, large-sample RCTs are required to ascertain its long-term effectiveness conclusively. TRIAL REGISTRATION: This study protocol was approved and registered in PROSPERO: CRD 42024509154.


Asunto(s)
Telerrehabilitación , Humanos , Enfermedad Crónica , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Prueba de Paso , Enfermedades Respiratorias/fisiopatología , Enfermedades Respiratorias/rehabilitación
11.
Clin Rehabil ; : 2692155241264757, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39053022

RESUMEN

OBJECTIVE: Post-stroke dysphagia is a common swallowing disorder that occurs after a stroke, leading to an increased risk of aspiration pneumonia and malnutrition. There is a pressing need for effective and safe interventions for its rehabilitation. This review aims to answer two key scientific questions: (1) What is the efficacy of repetitive transcranial magnetic stimulation in the rehabilitation of post-stroke dysphagia? (2) Is repetitive transcranial magnetic stimulation a safe intervention for post-stroke dysphagia? DATA SOURCES: A comprehensive search was conducted across four electronic databases: PubMed, Cochrane Library, Web of Science, and Embase. The search aimed to identify relevant studies concerning our topic of interest and was completed on 28 May 2024. REVIEW METHODS: In accordance with the PRISMA checklist, a comprehensive search of four databases was conducted, which identified 13 relevant systematic reviews. The inclusion criteria were systematic reviews that evaluated the efficacy and safety of repetitive transcranial magnetic stimulation for post-stroke dysphagia. Exclusion criteria were reviews that did not focus on post-stroke dysphagia or did not evaluate repetitive transcranial magnetic stimulation as a therapeutic intervention. The quality, bias, reporting, and overall evidence quality of these reviews were assessed using validated tools, including the AMSTAR 2 tool for assessing the methodological quality of systematic reviews, the ROBIS tool for assessing the risk of bias, and the GRADE approach for evaluating the overall quality of evidence. This rigorous approach ensures that our review provides a comprehensive and reliable overview of the current state of knowledge on the use of repetitive transcranial magnetic stimulation for post-stroke dysphagia. RESULTS: The sample sizes for the individual studies included in the systematic reviews/meta-analyses ranged from 66 to 555. The total number of participants across all studies included in the overall analyses was 752. The evidence was limited by the methodological flaws and heterogeneity of the systematic reviews. The quality of the evidence varied from high to low, with most outcomes having moderate quality. Future research should adopt more rigorous, standardized, and comprehensive designs to confirm the efficacy and safety of repetitive transcranial magnetic stimulation for post-stroke dysphagia. The main reason for downgrading the evidence quality was the small sample size and high heterogeneity of the primary studies. CONCLUSION: This overview synthesized research on repetitive transcranial magnetic stimulation for dysphagia, aiming to inform clinical and policy decisions. However, the current evidence does not conclusively establish the safety and efficacy of repetitive transcranial magnetic stimulation for post-stroke dysphagia rehabilitation. The studies reviewed varied in quality, and many were of poor quality. Therefore, while some studies suggest potential benefits of repetitive transcranial magnetic stimulation, these findings should be interpreted with caution. There is a pressing need for more rigorous, high-quality research to validate the use of repetitive transcranial magnetic stimulation for post-stroke dysphagia rehabilitation. The implications of these findings for clinical practice and policy will be clearer once we have more robust, evidence-based recommendations.

12.
Mycopathologia ; 189(2): 30, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578519

RESUMEN

OBJECTIVE: To study the distribution of pathogenic Aspergillus strains of otomycosis in central China and the identification of their antifungal sensitivity. METHODS: We collected external ear canal secretions clinically diagnosed as otomycosis from April 2020 to January 2023 from the Department of Otolaryngology-Head and Neck Surgery in central China. The pathogenic Aspergillus strains were identified through morphological examination and sequencing. The antifungal sensitivity was performed using the broth microdilution method described in the Clinical Laboratory Standard Institute document M38-A3. RESULTS: In the 452 clinical strains isolated from the external ear canal, 284 were identified as Aspergillus terreus (62.83%), 92 as Aspergillus flavus (20.35%), 55 as Aspergillus niger (12.17%). In antifungal susceptibility tests the MIC of Aspergillus strains to bifonazole and clotrimazole was high,all the MIC90 is > 16 ug/mL. However, most Aspergillus isolates show moderate greatly against terbinafine, itraconazole and voriconazole. CONCLUSION: A. terreus is the most common pathogenic Aspergillus strain in otomycosis in central China. The selected topical antifungal drugs were bifonazole and clotrimazole; the drug resistance rate was approximately 30%. If the infection is persistent and requires systemic treatment, terbinafine and itraconazole can be used. The resistance of Aspergillus in otomycosis to voriconazole should be screened to avoid the systemic spread of infection in immunocompromised people and poor compliance with treatment. However, the pan-azole-resistant strain of Aspergillus should be monitored, particularly in high-risk patients with otomycosis.


Asunto(s)
Aspergilosis , Otomicosis , Humanos , Antifúngicos/farmacología , Otomicosis/epidemiología , Otomicosis/microbiología , Itraconazol , Voriconazol , Terbinafina , Clotrimazol/farmacología , Aspergilosis/epidemiología , Aspergilosis/microbiología , Aspergillus , Pruebas de Sensibilidad Microbiana
13.
Mycopathologia ; 189(1): 4, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38231458

RESUMEN

BACKGROUND: Recently, the prevalence of invasive fungal infections has been on the rise, and one of the prevalent symptoms frequently observed is bone deterioration and bone loss. MATERIALS AND METHODS: Using an in vitro model we studied how Aspergillus fumigatus invades the bone. Pathological analysis was then employed to observe the structure and distinctive features of the invading fungal elements within the bone invasion model. Meanwhile, the antifungal effects of itraconazole, voriconazole, posaconazole, and amphotericin B were evaluated. RESULTS: The pathological findings showed that in the experimental group, fungal spores and hyphae invaded the bone tissue or were observed growing in the vicinity of the bone edge tissues, as indicated by both HE and PAS staining. In contrast, no fungal elements were observed in the control group, indicating that the in vitro bone invasion model of A. fumigatus was successfully constructed. Furthermore, the findings from the antifungal sensitivity test demonstrated that the lowest effective concentrations of antifungal drugs against the bone invasion model were as follows: 4 µg/ml for itraconazole, 0.5 µg/ml for voriconazole, 2 µg/ml for posaconazole, and 2 µg/ml for amphotericin B. DISCUSSION: The successful construction of the bone invasion model of A. fumigatus has provided a solid basis for future investigations into the mechanisms underlying A. fumigatus bone invasion and the study of its virulence factors. Utilizing bone models is of utmost importance in advancing the development of novel antifungal treatment approaches, as well as in effectively preventing and treating fungal bone invasion and osteolytic diseases.


Asunto(s)
Antifúngicos , Itraconazol , Antifúngicos/farmacología , Itraconazol/farmacología , Voriconazol/farmacología , Anfotericina B/farmacología , Aspergillus fumigatus , Huesos
14.
Sensors (Basel) ; 24(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38732988

RESUMEN

In this paper, we consider the problem of asynchronous estimation in the presence of packet losses for the randomly sampling nonlinear system. Packet losses occur at the control input and at the measurement side. Firstly, the synchronization of the asynchronous sampling system is realized by weighting the state of the adjacent state update points. Secondly, the projection theorem is used to estimate the system state at the sampling time. Due to modeling errors and unmodeled dynamics, obtaining an accurate dynamic model is challenging. Therefore, observation inference based on interpolation techniques is proposed to solve the asynchronous estimation problem. Furthermore, the algorithm is extended to multi-sensor systems to obtain a distributed fusion estimator. Finally, simulation experiments are conducted to validate the effectiveness of the algorithm.

15.
Nano Lett ; 23(14): 6474-6481, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37428132

RESUMEN

In this work, an ordered membrane electrode assembly (MEA) based on a cone Nafion array with gradient Nafion distribution, tightly bonded catalytic layer/proton exchange membrane (CL/PEM) interface, and abundant vertical channels has been engineered by an anodic aluminum oxide template and magnetron sputtering method. Benefiting from a highly efficient CL/PEM interface, plentiful proton transfer highways, and rapid oxygen bubble release, this ordered MEA achieves an ultralow Ir loading of 20.0 µg cm-2 and a high electrochemical active area by 8.7 times compared to traditional MEA with Ir loading of 1.0 mg cm-2. It yields a mass activity of 168 000 mA mgIr-1 cm-2 at 2.0 V, which is superior to most reported PEM electrolyzers. Notably, this ordered MEA maintains excellent durability at a current density of 500 mA cm-2. This work opens a simple, cost-effective, and scalable route to design ordered MEAs for proton exchange membrane water electrolysis.

16.
Nurs Health Sci ; 26(1): e13078, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38355889

RESUMEN

This study explored the mediating effect of resilience on clinical belongingness and presenteeism of new nurses. A total of 271 new nurses completed the Connor-Davidson Resilience Scale, Belongingness Scale-Clinical Placement Experience, and Stanford Presenteeism Scale. It was found that resilience correlated positively with clinical belongingness, while presenteeism was negatively correlated with resilience and clinical belongingness. The mediating effect of resilience on clinical belongingness and implicit absence accounted for 42% of the total effect value. Hence, new nurses' resilience plays an intermediary role between clinical belongingness and presenteeism. Nursing managers can develop interventions to reduce the sense of clinical absence by improving the resilience of new nurses.


Asunto(s)
Pruebas Psicológicas , Resiliencia Psicológica , Humanos , Presentismo , Encuestas y Cuestionarios
17.
Mol Biol Evol ; 39(2)2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-34893856

RESUMEN

Domestic sheep and their wild relatives harbor substantial genetic variants that can form the backbone of molecular breeding, but their genome landscapes remain understudied. Here, we present a comprehensive genome resource for wild ovine species, landraces and improved breeds of domestic sheep, comprising high-coverage (∼16.10×) whole genomes of 810 samples from 7 wild species and 158 diverse domestic populations. We detected, in total, ∼121.2 million single nucleotide polymorphisms, ∼61 million of which are novel. Some display significant (P < 0.001) differences in frequency between wild and domestic species, or are private to continent-wide or individual sheep populations. Retained or introgressed wild gene variants in domestic populations have contributed to local adaptation, such as the variation in the HBB associated with plateau adaptation. We identified novel and previously reported targets of selection on morphological and agronomic traits such as stature, horn, tail configuration, and wool fineness. We explored the genetic basis of wool fineness and unveiled a novel mutation (chr25: T7,068,586C) in the 3'-UTR of IRF2BP2 as plausible causal variant for fleece fiber diameter. We reconstructed prehistorical migrations from the Near Eastern domestication center to South-and-Southeast Asia and found two main waves of migrations across the Eurasian Steppe and the Iranian Plateau in the Early and Late Bronze Ages. Our findings refine our understanding of genome variation as shaped by continental migrations, introgression, adaptation, and selection of sheep.


Asunto(s)
Genoma , Oveja Doméstica , Animales , Asia , Europa (Continente) , Variación Genética , Irán , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , Ovinos/genética , Oveja Doméstica/genética
18.
Anal Chem ; 95(4): 2278-2284, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36647798

RESUMEN

Cardiac troponin I (cTnI) is the biomarker of choice and considered a gold standard for the diagnosis of acute myocardial infarction. However, the quantitative results of cTnI assay kits from different manufacturers are not comparable. Based on the H/D exchange mass spectrometry (HDX-MS) workflow, we developed an in-vitro diagnostic reagent antibody evaluation strategy to analyze the interactions of epitopes and antibody cocktails─(R195, F12, S13) and (D1, D2, pAb2). The HDX results indicate that the quantitative result bias of the different reagents originates from the ability of antibodies to recognize various cTnI complex forms, such as free cTnI, hydrolyzed cTnI, and cTnI combined with cTnT or TnC as binary or ternary complexes (cTnIC, cTnTIC), in blood based on different epitopes. The data obtained from the peptide HDX of interest after treatment with various antibody cocktails clearly indicated epitope specificity. The consistency of quantitative results can be improved by a thorough investigation into the epitopes recognized by the antibodies of various diagnostic kits, which will lead to the standardization of cTnI diagnosis.


Asunto(s)
Troponina I , Troponina T , Mapeo Epitopo , Indicadores y Reactivos , Anticuerpos , Epítopos , Biomarcadores , Espectrometría de Masas
19.
Biochem Biophys Res Commun ; 679: 116-121, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37683456

RESUMEN

Increased phosphoinositide signaling is commonly associated with cancers. While "one-drug one-target" has been a major drug discovery strategy for cancer therapy, a "one-drug multi-targets" approach for phosphoinositide enzymes has the potential to offer a new therapeutic approach. In this study, we sought a new way to target phosphoinositides metabolism. Using a high-throughput phosphatidylinositol 5-phosphate 4-kinase-alpha (PI5P4Kα) assay, we have identified that the immunosuppressor KRP203/Mocravimod induces a significant perturbation in phosphoinositide metabolism in U87MG glioblastoma cells. Despite high sequence similarity of PI5P4K and PI4K isozymes, in vitro kinase assays showed that KRP203 activates some (e.g., PI5P4Kα, PI4KIIß) while inhibiting other phosphoinositide kinases (e.g., PI5P4Kß, γ, PI4KIIα, class I PI3K-p110α, δ, γ). Furthermore, KRP203 enhances PI3P5K/PIKFYVE's substrate selectivity for phosphatidylinositol (PI) while preserving its selectivity for PI(3)P. At cellular levels, 3 h of KRP203 treatment induces a prominent increase of PI(3)P and moderate increase of PI(5)P, PI(3,5)P2, and PI(3,4,5)P3 levels in U87MG cells. Collectively, the finding of multimodal activity of KRP203 towards multi-phosphoinositide kinases may open a novel basis to modulate cellular processes, potentially leading to more effective treatments for diseases associated with phosphoinositide signaling pathways.

20.
J Hum Genet ; 68(12): 835-842, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37648893

RESUMEN

This study aims to investigate the correlations between islet function/ insulin resistance and serum lipid levels, as well as to assess whether the strength of such correlations is affected by the GCKR rs1260326 variant in healthy and T2D individuals. We performed an oral glucose tolerance test (OGTT) on 4889 middle-aged adults, including 3135 healthy and 1754 T2D individuals from the REACTION population study in the Nanjing region. We also measured their serum lipid levels and genotyped for rs1260326. We found that serum high-density lipoprotein (HDL) cholesterol and triglyceride (TG) levels were independently correlated with indexes of islet function (HOMA-ß and IGI [insulinogenic index]) and insulin resistance (HOMO-IR and ISIMatsuda) in both healthy and T2D individuals. The correlations were significantly decreased in T2D individuals, with significant heterogeneities compared to healthy controls (I2 > 75%, Phet < 0.05). Although no correlation was observed between serum total cholesterol (TC) level and islet function/ insulin resistance in healthy controls, significant correlations were found in T2D individuals, with significant heterogeneity to healthy controls in the correlation with ISIMatsuda(I2 = 85.3%, Phet = 0.009). Furthermore, we found significant interactions of the GCKR rs1260326 variant for the correlations between serum HDL cholesterol and HOMA-ß/ISIMatsuda in T2D subjects (P = 0.015 and 0.038, respectively). These findings illustrate that distinct correlations between serum lipid levels and islet function/ insulin resistance occurred in T2D subjects compared to healthy individuals. Common gene variants, such as rs1260326, might interact substantially when studied in specific populations, especially T2D disease status.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Adulto , Persona de Mediana Edad , Humanos , Resistencia a la Insulina/genética , HDL-Colesterol , Triglicéridos , Glucemia , Proteínas Adaptadoras Transductoras de Señales/genética
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