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1.
J Am Chem Soc ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982611

RESUMEN

The structural dynamics of artificial assemblies, in aspects such as molecular recognition and structural transformation, provide us with a blueprint to achieve bioinspired applications. Here, we describe the assembly of redox-switchable chiral metal-organic cages Λ8/Δ8-[Pd6(CoIIL3)8]28+ and Λ8/Δ8-[Pd6(CoIIIL3)8]36+. These isomeric cages demonstrate an on-off chirality logic gate controlled by their chemical and stereostructural dynamics tunable through redox transitions between the labile CoII-state and static CoIII-state with a distinct Cotton effect. The transition between different states is enabled by a reversible redox process and chiral recognition originating in the tris-chelate Co-centers. All cages in two states are thoroughly characterized by NMR, ESI-MS, CV, CD, and X-ray crystallographic analysis, which clarify their redox-switching behaviors upon chemical reduction/oxidation. The stereochemical lability of the CoII-center endows the Λ8/Δ8-CoII-cages with efficient chiral-induction by enantiomeric guests, leading to enantiomeric isomerization to switch between Λ8/Δ8-CoII-cages, which can be stabilized by oxidation to their chemically inert forms of Λ8/Δ8-CoIII-cages. Kinetic studies reveal that the isomerization rate of the Δ8-CoIII-cage is at least an order of magnitude slower than that of the Δ8-CoII-cage even at an elevated temperature, while its activation energy is 16 kcal mol-1 higher than that of the CoII-cage.

2.
Genetics ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38984710

RESUMEN

Centromeric localization of evolutionarily conserved CENP-A (Cse4 in Saccharomyces cerevisiae) is essential for chromosomal stability. Mislocalization of overexpressed CENP-A to non-centromeric regions contributes to chromosomal instability (CIN) in yeasts, flies, and humans. Overexpression and mislocalization of CENP-A observed in many cancers is associated with poor prognosis. Previous studies have shown that F-box proteins, Cdc4 and Met30 of the Skp, Cullin, F-box (SCF) ubiquitin ligase cooperatively regulate proteolysis of Cse4 to prevent Cse4 mislocalization and CIN under normal physiological conditions. Mck1-mediated phosphorylation of SCF-Cdc4 substrates such as Cdc6 and Rcn1 enhances the interaction of the substrates with Cdc4. Here, we report that Mck1 interacts with Cse4, and Mck1-mediated proteolysis of Cse4 prevents Cse4 mislocalization for chromosomal stability. Our results showed that mck1Δ strain overexpressing CSE4 (GAL-CSE4) exhibits lethality, defects in ubiquitin-mediated proteolysis of Cse4, mislocalization of Cse4 and reduced Cse4-Cdc4 interaction. Strain expressing GAL-cse4-3A with mutations in three potential Mck1 phosphorylation consensus site (S10, S16, and T166) also exhibits growth defects, increased stability with mislocalization of Cse4-3A, CIN, and reduced interaction with Cdc4. Constitutive expression of histone H3 (Δ16H3) suppresses the CIN phenotype of GAL-cse4-3A strain, suggesting that the CIN phenotype is linked to Cse4-3A mislocalization. We conclude that Mck1 and its three potential phosphorylation sites on Cse4 promote Cse4-Cdc4 interaction and this contributes to ubiquitin-mediated proteolysis of Cse4 preventing its mislocalization and CIN. These studies advance our understanding of pathways that regulate cellular levels of CENP-A to prevent mislocalization of CENP-A in human cancers.

3.
Front Mol Neurosci ; 17: 1345864, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38989156

RESUMEN

Neuropathic pain is a type of chronic pain caused by an injury or somatosensory nervous system disease. Drugs and exercise could effectively relieve neuropathic pain, but no treatment can completely stop neuropathic pain. The integration of exercise into neuropathic pain management has attracted considerable interest in recent years, and treadmill training is the most used among exercise therapies. Neuropathic pain can be effectively treated if its mechanism is clarified. In recent years, the association between neuroinflammation and neuropathic pain has been explored. Neuroinflammation can trigger proinflammatory cytokines, activate microglia, inhibit descending pain modulatory systems, and promote the overexpression of brain-derived neurotrophic factor, which lead to the generation of neuropathic pain and hypersensitivity. Treadmill exercise can alleviate neuropathic pain mainly by regulating neuroinflammation, including inhibiting the activity of pro-inflammatory factors and over activation of microglia in the dorsal horn, regulating the expression of mu opioid receptor expression in the rostral ventromedial medulla and levels of γ-aminobutyric acid to activate the descending pain modulatory system and the overexpression of brain-derived neurotrophic factor. This article reviews and summarizes research on the effect of treadmill exercise on neuropathic pain and its role in the regulation of neuroinflammation to explore its benefits for neuropathic pain treatment.

4.
Food Chem Toxicol ; 190: 114809, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38857761

RESUMEN

This Special Issue contains articles on applications of various new approach methodologies (NAMs) in the field of toxicology and risk assessment. These NAMs include in vitro high-throughput screening, quantitative structure-activity relationship (QSAR) modeling, physiologically based pharmacokinetic (PBPK) modeling, network toxicology analysis, molecular docking simulation, omics, machine learning, deep learning, and "template-and-anchor" multiscale computational modeling. These in vitro and in silico approaches complement each other and can be integrated together to support different applications of toxicology, including food safety assessment, dietary exposure assessment, chemical toxicity potency screening and ranking, chemical toxicity prediction, chemical toxicokinetic simulation, and to investigate the potential mechanisms of toxicities, as introduced further in selected articles in this Special Issue.


Asunto(s)
Inocuidad de los Alimentos , Aprendizaje Automático , Medición de Riesgo/métodos , Humanos , Relación Estructura-Actividad Cuantitativa , Toxicocinética , Toxicología/métodos
5.
Environ Toxicol ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884142

RESUMEN

Environmental antineoplastics such as sorafenib may pose a risk to humans through water recycling, and the increased risk of cardiotoxicity is a clinical issue in sorafenib users. Thus, developing strategies to prevent sorafenib cardiotoxicity is an urgent work. Empagliflozin, as a sodium-glucose co-transporter-2 (SGLT2) inhibitor for type 2 diabetes control, has been approved for heart failure therapy. Still, its cardioprotective effect in the experimental model of sorafenib cardiotoxicity has not yet been reported. Real-time quantitative RT-PCR (qRT-PCR), immunoblot, and immunohistochemical analyses were applied to study the effect of sorafenib exposure on cardiac SGLT2 expression. The impact of empagliflozin on cell viability was investigated in the sorafenib-treated cardiomyocytes using Alamar blue assay. Immunoblot analysis was employed to delineate the effect of sorafenib and empagliflozin on ferroptosis/proinflammatory signaling in cardiomyocytes. Ferroptosis/DNA damage/fibrosis/inflammation of myocardial tissues was studied in mice with a 28-day sorafenib ± empagliflozin treatment using histological analyses. Sorafenib exposure significantly promoted SGLT2 upregulation in cardiomyocytes and mouse hearts. Empagliflozin treatment significantly attenuated the sorafenib-induced cytotoxicity/DNA damage/fibrosis in cardiomyocytes and mouse hearts. Moreover, GPX4/xCT-dependent ferroptosis as an inducer for releasing high mobility group box 1 (HMGB1) was also blocked by empagliflozin administration in the sorafenib-treated cardiomyocytes and myocardial tissues. Furthermore, empagliflozin treatment significantly inhibited the sorafenib-promoted NFκB/HMGB1 axis in cardiomyocytes and myocardial tissues, and sorafenib-stimulated proinflammatory signaling (TNF-α/IL-1ß/IL-6) was repressed by empagliflozin administration. Finally, empagliflozin treatment significantly attenuated the sorafenib-promoted macrophage recruitments in mouse hearts. In conclusion, empagliflozin may act as a cardioprotective agent for humans under sorafenib exposure by modulating ferroptosis/DNA damage/fibrosis/inflammation. However, further clinical evidence is required to support this preclinical finding.

6.
Chembiochem ; : e202400269, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923255

RESUMEN

The human malaria parasite Plasmodium falciparum (P. falciparum) continues to pose a significant public health challenge, leading to millions of fatalities globally. Halofuginone (HF) has shown a significant anti-P. falciparum effect, suggesting its potential as a therapeutic agent for malaria treatment. In this study, we synthesized a photoaffinity labeling probe of HF to identify its direct target in P. falciparum. Our results reveal that ubiquitin carboxyl-terminal hydrolase 3 (PfUCHL3) acts as a crucial target protein of HF, which modulates parasite growth in the intraerythrocytic cycle. In particular, we discovered that HF potentially forms hydrogen bonds with the Leu10, Glu11, and Arg217 sites of PfUCHL3, thereby inducing an allosteric effect by promoting the embedding of the helix 6' region on the protein surface. Furthermore, HF disrupts the expression of multiple functional proteins mediated by PfUCHL3, specifically those that play crucial roles in amino acid biosynthesis and metabolism in P. falciparum. Taken together, this study highlights PfUCHL3 as a previously undisclosed druggable target of HF, which contributes to the development of novel anti-malarial agents in the future.

7.
Vaccines (Basel) ; 12(6)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38932387

RESUMEN

BACKGROUND: The impact of mRNA COVID-19 vaccines on the immunological profiles of pregnant women remains a crucial area of study. This research aims to explore the specific immunological changes triggered by these vaccines in this demographic. METHODS: In a focused investigation, we examined the effects of mRNA COVID-19 vaccination on microRNA expression in pregnant women. Key microRNAs, including miR-451a, miR-23a-3p, and miR-21-5p, were analyzed for expression changes post-vaccination. Additionally, we assessed variations in S1RBD IgG levels and specific cytokines to gauge the broader immunological response. RESULTS: Post-vaccination, significant expression shifts in the targeted microRNAs were observed. Alongside these changes, we noted alterations in S1RBD IgG and various cytokines, indicating an adapted inflammatory response. Notably, these immunological markers displayed no direct correlation with S1RBD IgG concentrations, suggesting a complex interaction between the vaccine and the immune system in pregnant women. CONCLUSIONS: Our pilot study provides valuable insights into the nuanced effects of the mRNA COVID-19 vaccine on immune dynamics in pregnant women, particularly emphasizing the role of microRNAs. The findings illuminate the intricate interplay between vaccines, microRNAs, and immune responses, enhancing our understanding of these relationships in the context of pregnancy. This research contributes significantly to the growing body of knowledge regarding mRNA COVID-19 vaccines and their specific impact on maternal immunology, offering a foundation for further studies in this vital area.

8.
AMIA Jt Summits Transl Sci Proc ; 2024: 603-612, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38827073

RESUMEN

Clinical research data visualization is integral to making sense of biomedical research and healthcare data. The complexity and diversity of data, along with the need for solid programming skills, can hinder advances in clinical research data visualization. To overcome these challenges, we introduce VisualSphere, a web-based interactive visualization system that directly interfaces with clinical research data repositories, streamlining and simplifying the visualization workflow. VisualSphere is founded on three primary component modules: Connection, Configuration, and Visualization. An end-user can set up connections to the data repositories, create charts by selecting the desired tables and variables, and render visualization dashboards generated by Plotly and R/Shiny. We performed a preliminary evaluation of VisualSphere, which achieved high user satisfaction. VisualSphere has the potential to serve as a versatile tool for various clinical research data repositories, enabling researchers to explore and interact with clinical research data efficiently and effectively.

9.
PLoS One ; 19(6): e0304941, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38865375

RESUMEN

BACKGROUND: The recent usage of immunotherapy combined with chemoradiotherapy has improved survival in advanced non-small cell lung cancer (NSCLC) patients. However, determining the most effective therapy combination remains a topic of debate. Research suggests immune checkpoint inhibitors (ICIs) post-chemoradiotherapy enhance survival, but the impact of concurrent ICIs during chemoradiotherapy on rapid disease progression is unclear. This meta-analysis aims to assess the effectiveness and safety of concurrent ICIs with radiotherapy or chemoradiotherapy in advanced non-small cell lung cancer. METHODS: We searched PubMed, Embase, the Cochrane Library, and Web of Science for relevant studies, extracting data on overall response rate (ORR), progression-free survival (PFS), overall survival (OS), and adverse events (AEs). RESULTS: The analysis included ten studies with 490 participants. Stage III NSCLC ORR was 81.8%, while Stage IV ORR was 39.9%. One-year PFS and OS for Stage III were 68.2% and 82.6%, compared to 27.9% and 72.2% for Stage IV. Common adverse events included anemia (46.6%), nausea (47.6%), rash (36.4%), and radiation pneumonitis (36.3%). CONCLUSIONS: Our meta-analysis shows concurrent ICIs with chemoradiotherapy are effective and safe in advanced NSCLC, particularly in stage III patients at risk of progression before starting ICIs after chemoradiotherapy. The findings support further phase III trials. The review protocol was registered on PROSPERO (CRD42023493685) and is detailed on the NIHR HTA programme website.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Quimioradioterapia , Inhibidores de Puntos de Control Inmunológico , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/terapia , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/tratamiento farmacológico , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Supervivencia sin Progresión , Resultado del Tratamiento
10.
Eur J Pharmacol ; 977: 176682, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38823759

RESUMEN

The major limitation of cancer treatment is multidrug resistance (MDR), which leads to the inactivation of chemotherapeutic drugs and greater than 90% mortality. To solve this ordeal, we applied ligand-based drug design and bioiosteric replacement strategy from an indazole to a pyrazole ring to discover compounds 27 and 43 with good potential for reversing drug resistance in combination with paclitaxel, and their reversal fold values were 53.2 and 51.0 at 5 µM, respectively, against an MDR cancer cell line (KBvin). Based on the PK profile results, we selected compound 43 with a longer half-life for mechanistic and animal experiments. Combination treatment with compound 43 and paclitaxel-induced apoptosis and enhanced subG1 by decreasing mitochondrial membrane potential in KBvin cells. In addition, 43 also inhibited P-gp function by interfering with ATPase activity. Meanwhile, cotreatment with compound 43 and paclitaxel significantly suppressed tumor growth (TGI = 55.5%) at a dose of 200 mg/kg (PO) in a xenograft model and showed no obvious liver or kidney toxicity by H&E staining. Overall, compound 43 may serve as a safe and effective oral resistance reversal chemotherapeutic agent.


Asunto(s)
Antineoplásicos , Apoptosis , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Paclitaxel , Humanos , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Animales , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Administración Oral , Ratones , Ensayos Antitumor por Modelo de Xenoinjerto , Descubrimiento de Drogas , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Desnudos
11.
Nat Methods ; 21(7): 1340-1348, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38918604

RESUMEN

The EMDataResource Ligand Model Challenge aimed to assess the reliability and reproducibility of modeling ligands bound to protein and protein-nucleic acid complexes in cryogenic electron microscopy (cryo-EM) maps determined at near-atomic (1.9-2.5 Å) resolution. Three published maps were selected as targets: Escherichia coli beta-galactosidase with inhibitor, SARS-CoV-2 virus RNA-dependent RNA polymerase with covalently bound nucleotide analog and SARS-CoV-2 virus ion channel ORF3a with bound lipid. Sixty-one models were submitted from 17 independent research groups, each with supporting workflow details. The quality of submitted ligand models and surrounding atoms were analyzed by visual inspection and quantification of local map quality, model-to-map fit, geometry, energetics and contact scores. A composite rather than a single score was needed to assess macromolecule+ligand model quality. These observations lead us to recommend best practices for assessing cryo-EM structures of liganded macromolecules reported at near-atomic resolution.


Asunto(s)
Microscopía por Crioelectrón , Modelos Moleculares , Microscopía por Crioelectrón/métodos , Ligandos , SARS-CoV-2 , COVID-19/virología , Escherichia coli , beta-Galactosidasa/química , beta-Galactosidasa/metabolismo , Conformación Proteica , Reproducibilidad de los Resultados
12.
Artículo en Inglés | MEDLINE | ID: mdl-38845599

RESUMEN

BACKGROUND: Cardiorespiratory fitness (CRF) could reduce the risk of metabolic syndrome (MetS) while the association between muscular endurance capacity (MEC) and incident MetS has rarely been investigated in young adults. METHODS: A total of 2890 military men and women, aged 18-39 years, free of baseline MetS in Taiwan, were followed for incident MetS from baseline (2014) until the end of 2020. All subjects received annual health examinations for assessment of MetS. Physical fitness was assessed by CRF (estimated maximal oxygen uptake, VO2 max [mL/kg/min], in a 3000-m run) and MEC (numbers of 2-min push-ups). MetS was defined according to the International Diabetes Federation (IDF) criteria. Multiple Cox regression analysis was conducted with adjustments for baseline age, sex, substance use status and physical activity to determine the associations of CRF and MEC with incidences of new-onset MetS and related features, for example, central obesity, hypertension, dyslipidaemia and prediabetes or diabetes. To examine the combined effects of CRF and MEC status on incidence of MetS, high and low levels of CRF and MEC were separately defined by over and under the sex-specific median in each exercise test. RESULTS: During a median follow-up of 5.8 years, there were 673 (23.3%) new-onset MetS. Higher CRF was associated with a lower incidence of MetS (hazard ratio [HR] and 95% confidence interval: 0.905 [0.877-0.933]), and its components separately, except hypertension. No association was observed between MEC and incident MetS, and its components separately, except hypertension. When evaluating the combined effects of MEC and CRF status on the incidence of MetS, it was observed that compared with the low CRF/low MEC, the high CRF/high MEC (HR: 0.553 [0.439-0.697]) and the high CRF/low MEC (HR: 0.730 [0.580-0.918]) had a lower incidence of new-onset MetS (P value for the intergroup difference = 0.04). There was no significant result for the low CRF/high MEC. CONCLUSIONS: This study highlights that although the protective effects of MEC to reduce the incidence of MetS and most of its related features were mainly driven by CRF in young adults, there was an addictive effect of greater MEC on CRF to prevent the development of new-onset MetS before midlife.

13.
Radiol Cardiothorac Imaging ; 6(3): e230278, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38780426

RESUMEN

Purpose To develop a prediction model combining both clinical and CT texture analysis radiomics features for predicting pneumothorax complications in patients undergoing CT-guided core needle biopsy. Materials and Methods A total of 424 patients (mean age, 65.6 years ± 12.7 [SD]; 232 male, 192 female) who underwent CT-guided core needle biopsy between January 2021 and October 2022 were retrospectively included as the training data set. Clinical and procedure-related characteristics were documented. Texture analysis radiomics features were extracted from the subpleural lung parenchyma traversed by needle. Moderate pneumothorax was defined as a postprocedure air rim of 2 cm or greater. The prediction model was developed using logistic regression with backward elimination, presented by linear fusion of the selected features weighted by their coefficients. Model performance was assessed using the area under the receiver operating characteristic curve (AUC). Validation was conducted in an external cohort (n = 45; mean age, 58.2 years ± 12.7; 19 male, 26 female) from a different hospital. Results Moderate pneumothorax occurred in 12.0% (51 of 424) of the training cohort and 8.9% (four of 45) of the external test cohort. Patients with emphysema (P < .001) or a longer needle path length (P = .01) exhibited a higher incidence of moderate pneumothorax in the training cohort. Texture analysis features, including gray-level co-occurrence matrix cluster shade (P < .001), gray-level run-length matrix low gray-level run emphasis (P = .049), gray-level run-length matrix run entropy (P = .003), gray-level size-zone matrix gray-level variance (P < .001), and neighboring gray-tone difference matrix complexity (P < .001), showed higher values in patients with moderate pneumothorax. The combined clinical-radiomics model demonstrated satisfactory performance in both the training (AUC 0.78, accuracy = 71.9%) and external test cohorts (AUC 0.86, accuracy 73.3%). Conclusion The model integrating both clinical and radiomics features offered practical diagnostic performance and accuracy for predicting moderate pneumothorax in patients undergoing CT-guided core needle biopsy. Keywords: Biopsy/Needle Aspiration, Thorax, CT, Pneumothorax, Core Needle Biopsy, Texture Analysis, Radiomics, CT Supplemental material is available for this article. © RSNA, 2024.


Asunto(s)
Biopsia Guiada por Imagen , Neumotórax , Tomografía Computarizada por Rayos X , Humanos , Neumotórax/etiología , Neumotórax/epidemiología , Neumotórax/diagnóstico por imagen , Masculino , Femenino , Anciano , Biopsia Guiada por Imagen/métodos , Biopsia Guiada por Imagen/efectos adversos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Biopsia con Aguja Gruesa/métodos , Biopsia con Aguja Gruesa/efectos adversos , Persona de Mediana Edad , Radiografía Intervencional/métodos , Pulmón/patología , Pulmón/diagnóstico por imagen , Valor Predictivo de las Pruebas , Radiómica
14.
Langmuir ; 40(23): 11873-11887, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38780396

RESUMEN

In recent years, organic-inorganic hybrid perovskite materials have become one of the most promising materials in the new generation of solar cells. These perovskites can provide excellent photoelectric properties after a simple fabrication process. Although perovskite solar cells have achieved high power conversion efficiency, instability concerns regarding material exposure to heat, moisture, air, and UV light present hindrances to commercialization. In this study, three kinds of perovskites (MAPbI3, MAPbI3-xBrx, and MAPbI3-xClx) were used to investigate the crystal stability upon exposure to heat and UV light. SEM, XRD, and FTIR were used to observe the surface morphology, crystal structure, and functional groups of the perovskite thin films. XPS was used to examine the surface composition and chemical state of the perovskite thin films under different conditions. Among these three types of perovskites, it was found that the MAPbI3-xBrx crystal demonstrated the best stability. ToF-SIMS was used to confirm the molecular distribution of the MAPbI3-xBrx films upon exposure to heat and UV light at different depths. ToF-SIMS revealed that [Pb]+ and [PbI]+ aggregated at the interface between the perovskite and ITO substrate after 14 days of thermal treatment. On the other hand, [Pb]+ and [PbI]+ were distributed uniformly after 3 days of UV exposure. This study systematically analyzed and revealed the thermal- and UV-induced degradation process of three perovskite films by using surface analysis techniques. It was concluded that bromine-doped perovskite films had better stability, and UV light caused more severe damage than heat.

15.
Sci Signal ; 17(836): eadd5073, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38743809

RESUMEN

The Ras-mitogen-activated protein kinase (MAPK) pathway is a major target for cancer treatment. To better understand the genetic pathways that modulate cancer cell sensitivity to MAPK pathway inhibitors, we performed a CRISPR knockout screen with MAPK pathway inhibitors on a colorectal cancer (CRC) cell line carrying mutant KRAS. Genetic deletion of the catalytic subunit of protein phosphatase 6 (PP6), encoded by PPP6C, rendered KRAS- and BRAF-mutant CRC and BRAF-mutant melanoma cells more resistant to these inhibitors. In the absence of MAPK pathway inhibition, PPP6C deletion in CRC cells decreased cell proliferation in two-dimensional (2D) adherent cultures but accelerated the growth of tumor spheroids in 3D culture and tumor xenografts in vivo. PPP6C deletion enhanced the activation of nuclear factor κB (NF-κB) signaling in CRC and melanoma cells and circumvented the cell cycle arrest and decreased cyclin D1 abundance induced by MAPK pathway blockade in CRC cells. Inhibiting NF-κB activity by genetic and pharmacological means restored the sensitivity of PPP6C-deficient cells to MAPK pathway inhibition in CRC and melanoma cells in vitro and in CRC cells in vivo. Furthermore, a R264 point mutation in PPP6C conferred loss of function in CRC cells, phenocopying the enhanced NF-κB activation and resistance to MAPK pathway inhibition observed for PPP6C deletion. These findings demonstrate that PP6 constrains the growth of KRAS- and BRAF-mutant cancer cells, implicates the PP6-NF-κB axis as a modulator of MAPK pathway output, and presents a rationale for cotargeting the NF-κB pathway in PPP6C-mutant cancer cells.


Asunto(s)
Sistema de Señalización de MAP Quinasas , FN-kappa B , Proteínas Proto-Oncogénicas B-raf , Proteínas Proto-Oncogénicas p21(ras) , Humanos , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , FN-kappa B/metabolismo , FN-kappa B/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Animales , Línea Celular Tumoral , Mutación , Ratones , Inhibidores de Proteínas Quinasas/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Melanoma/genética , Melanoma/metabolismo , Melanoma/tratamiento farmacológico , Melanoma/patología , Ensayos Antitumor por Modelo de Xenoinjerto , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Ratones Desnudos
17.
Protein Sci ; 33(6): e5007, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723187

RESUMEN

The identification of an effective inhibitor is an important starting step in drug development. Unfortunately, many issues such as the characterization of protein binding sites, the screening library, materials for assays, etc., make drug screening a difficult proposition. As the size of screening libraries increases, more resources will be inefficiently consumed. Thus, new strategies are needed to preprocess and focus a screening library towards a targeted protein. Herein, we report an ensemble machine learning (ML) model to generate a CDK8-focused screening library. The ensemble model consists of six different algorithms optimized for CDK8 inhibitor classification. The models were trained using a CDK8-specific fragment library along with molecules containing CDK8 activity. The optimized ensemble model processed a commercial library containing 1.6 million molecules. This resulted in a CDK8-focused screening library containing 1,672 molecules, a reduction of more than 99.90%. The CDK8-focused library was then subjected to molecular docking, and 25 candidate compounds were selected. Enzymatic assays confirmed six CDK8 inhibitors, with one compound producing an IC50 value of ≤100 nM. Analysis of the ensemble ML model reveals the role of the CDK8 fragment library during training. Structural analysis of molecules reveals the hit compounds to be structurally novel CDK8 inhibitors. Together, the results highlight a pipeline for curating a focused library for a specific protein target, such as CDK8.


Asunto(s)
Quinasa 8 Dependiente de Ciclina , Evaluación Preclínica de Medicamentos , Aprendizaje Automático , Inhibidores de Proteínas Quinasas , Humanos , Quinasa 8 Dependiente de Ciclina/antagonistas & inhibidores , Quinasa 8 Dependiente de Ciclina/química , Quinasa 8 Dependiente de Ciclina/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología
18.
Ann Med ; 56(1): 2352019, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38747459

RESUMEN

PURPOSE: To offer consensus on the utilization of corticosteroids (CS) for treating non-infectious uveitis in the context of clinical practice in Taiwan. This entails examining the different administration methods, their advantages and disadvantages, and considering alternative treatments according to the prevailing evidence and health policies. METHODS: Ten ophthalmologists and one rheumatologist convened on December 11, 2022, to review and discuss literature on the topic. The databases explored were the Central Cochrane library, EMBASE, Medline, PUBMED, and Web of Science using relevant keywords. The search spanned from January 1996 to June 2023. After the initial results of the literature review were presented, open voting determined the final statements, with a statement being accepted if it secured more than 70% agreement. This consensus was then presented at significant meetings for further discussions before the final version was established. RESULTS: A flow chart and nine statements emerged from the deliberations. They address the importance of CS in uveitis management, guidelines for using topical CS, indications for both periocular or intravitreal and systemic therapies, and tapering and discontinuation methods for both topical and systemic CS. CONCLUSION: While CS are a cornerstone for non-infectious uveitis treatment, their administration requires careful consideration, depending on the clinical situation and the specific type of uveitis. The consensus generated from this article provides a guideline for practitioners in Taiwan, taking into account local health policies and the latest research on the subject. It emphasizes the significance of strategic tapering, the potential for alternative therapies, and the importance of patient-centric care.


Asunto(s)
Corticoesteroides , Consenso , Uveítis , Humanos , Uveítis/tratamiento farmacológico , Taiwán , Corticoesteroides/uso terapéutico , Corticoesteroides/administración & dosificación
19.
Pneumonia (Nathan) ; 16(1): 10, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38790032

RESUMEN

RATIONALE: The prevalence, clinical characteristics, and outcomes of invasive pulmonary aspergillosis in patients with severe community-acquired pneumonia (CAP) in intensive care units remain underestimated because of the lack of a disease-recognition scheme and the inadequacy of diagnostic tests. OBJECTIVES: To identify the prevalence, risk factors, and outcomes of severe CAP complicated with invasive pulmonary aspergillosis (IPA) in intensive care units (ICUs). METHODS: We conducted a retrospective cohort study including recruited 311 ICU-hospitalized patients with severe CAP without influenza or with influenza. Bronchoalveolar lavage fluid (BALF) samples were from all patients and subjected to mycological testing. Patients were categorized as having proven or probable Aspergillus infection using a modified form of the AspICU algorithm comprising clinical, radiological, and mycological criteria. MEASUREMENTS AND MAIN RESULTS: Of the 252 patients with severe CAP and 59 influenza patients evaluated, 24 met the diagnostic criteria for proven or probable Aspergillus infection in the CAP group and 9 patients in the influenza group, giving estimated prevalence values of 9.5% and 15.3%, respectively. COPD and the use of inhaled corticosteroids were independent risk factors for IPA. IPA in patients with severe CAP was significantly associated with the duration of mechanical support, the length of ICU stay, and the 28-day mortality. CONCLUSIONS: An aggressive diagnostic approach for IPA patients with severe CAP and not only influenza or COVID-19 should be pursued. Further randomized controlled trials need to evaluate the timing, safety, and efficacy of antifungal therapy in reducing IPA incidence and improving clinical outcomes.

20.
J Prosthodont ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38706414

RESUMEN

PURPOSE: To evaluate the effects of two base types and three restoration designs on the resin consumption and trueness of the 3D-printed dental casts. Additionally, the study explored the dimensional stability of these 3D-printed dental casts after 1 year of storage. MATERIALS AND METHODS: Various types of reference dental casts were specifically designed to represent three types of dental restoration fabrications, including full-arch (FA), long-span (LS), and single-unit (SU) prostheses. The reference casts were digitized with a dental laboratory scanner and used to create flat and hollow base designs (N = 18) for the 3D-printed study casts. The 3D-printed study casts were digitized and evaluated against their corresponding references immediately after 3D printing and again after 1 year of storage, with the trueness quantified using the root mean square error (RMSE) at both time points. Volumes of resin used were recorded to measure resin consumption, and the weights of the 3D-printed study casts were also measured. The data were analyzed using two-way ANOVA and a Tukey post hoc test, α = 0.05. RESULTS: Volumetric analysis showed the flat-base design had significantly higher resin consumption with weights for the FA group at 42.51 ± 0.16 g, the LS group at 31.64 ± 0.07 g, and the SU group at 27.67 ± 0.31 g, as opposed to 26.22 ± 1.01 g, 22.86 ± 0.93 g, and 20.10 ± 0.19 g for the hollow designs respectively (p < 0.001). Trueness, assessed through two-way ANOVA, revealed that the flat-base design had lower RMSE values indicating better trueness in the LS (54 ± 6 µm) and SU (59 ± 7 µm) groups compared to the hollow-base design (LS: 73 ± 5, SU: 99 ± 11 µm, both p < 0.001), with no significant difference in the FA group (flat-base: 50 ± 3, hollow: 47 ± 5 µm, p = 0.398). After 1 year, the flat-base design demonstrated superior dimensional stability in the LS (flat base: 56 ± 6 µm, hollow base: 149 ±45 µm, p < 0.001) and SU groups (flat base: 95 ± 8 µm, hollow base: 183 ±27 µm, p < 0.001), with the FA group showing no significant difference in the base design (flat base: 47 ± 9, hollow base: 62 ± 12 µm, p = 0.428). CONCLUSIONS: The hollow-base design group showed lower resin consumption than the flat-base design group. However, the flat-base designs exhibited superior trueness and less distortion after 1 year of storage. These findings indicate that despite the higher material usage, flat-base designs provide better initial accuracy and maintain their dimensional stability over time for most groups.

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