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1.
Mol Cell ; 84(12): 2368-2381.e6, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38834067

RESUMEN

The Tn7 family of transposons is notable for its highly regulated integration mechanisms, including programmable RNA-guided transposition. The targeting pathways rely on dedicated target selection proteins from the TniQ family and the AAA+ adaptor TnsC to recruit and activate the transposase at specific target sites. Here, we report the cryoelectron microscopy (cryo-EM) structures of TnsC bound to the TniQ domain of TnsD from prototypical Tn7 and unveil key regulatory steps stemming from unique behaviors of ATP- versus ADP-bound TnsC. We show that TnsD recruits ADP-bound dimers of TnsC and acts as an exchange factor to release one protomer with exchange to ATP. This loading process explains how TnsC assembles a heptameric ring unidirectionally from the target site. This unique loading process results in functionally distinct TnsC protomers within the ring, providing a checkpoint for target immunity and explaining how insertions at programmed sites precisely occur in a specific orientation across Tn7 elements.


Asunto(s)
Adenosina Difosfato , Adenosina Trifosfato , Microscopía por Crioelectrón , Elementos Transponibles de ADN , Transposasas , Elementos Transponibles de ADN/genética , Adenosina Trifosfato/metabolismo , Transposasas/metabolismo , Transposasas/genética , Transposasas/química , Adenosina Difosfato/metabolismo , Unión Proteica , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Modelos Moleculares , Multimerización de Proteína , Sitios de Unión
2.
Nature ; 631(8021): 531-536, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39020034

RESUMEN

The pursuit of discovering new high-temperature superconductors that diverge from the copper-based model1-3 has profound implications for explaining mechanisms behind superconductivity and may also enable new applications4-8. Here our investigation shows that the application of pressure effectively suppresses the spin-charge order in trilayer nickelate La4Ni3O10-δ single crystals, leading to the emergence of superconductivity with a maximum critical temperature (Tc) of around 30 K at 69.0 GPa. The d.c. susceptibility measurements confirm a substantial diamagnetic response below Tc, indicating the presence of bulk superconductivity with a volume fraction exceeding 80%. In the normal state, we observe a strange metal behaviour, characterized by a linear temperature-dependent resistance extending up to 300 K. Furthermore, the layer-dependent superconductivity observed hints at a unique interlayer coupling mechanism specific to nickelates, setting them apart from cuprates in this regard. Our findings provide crucial insights into the fundamental mechanisms underpinning superconductivity, while also introducing a new material platform to explore the intricate interplay between the spin-charge order, flat band structures, interlayer coupling, strange metal behaviour and high-temperature superconductivity.

3.
J Lipid Res ; 65(11): 100660, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39332525

RESUMEN

Hepatocellular carcinoma (HCC) poses significant treatment challenges due to high postoperative recurrence rates and the limited effectiveness of targeted medications. Researchers have identified the unique metabolic profiles of cancer stem cells (CSCs) as the primary drivers of cancer recurrence, metastasis, and drug resistance. Therefore, to address the therapeutic conundrum, this study focused on rewinding metabolic reprogramming of CSCs as a novel therapeutic strategy. HCC CSCs exhibited elevated fatty acid (FA) metabolism compared with parental cells. To specifically target FA metabolism in CSCs, we utilized cerulenin, a fatty acid synthase (FASN) inhibitor. Surprisingly, cerulenin can diminish CSC-like characteristics, including stemness gene expression, spherogenicity, tumorigenicity, and metastatic potential. In addition, sorafenib, a multikinase inhibitor used as targeted therapy for advanced HCC, was employed in combination with cerulenin, demonstrating a great synergistic effect, particularly in CSCs. Importantly, our RNA sequencing analysis disclosed that the amyloid protein precursor (APP) is a crucial downstream effector of FASN in regulating CSC properties. We found that APP plays a crucial role in CSCs' characteristics that can be inhibited by cerulenin. By focusing on FA metabolism, this study identified the FASN/APP axis as a viable target to develop a more potent therapy strategy for advanced HCC.

4.
Infect Immun ; 92(5): e0011324, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38624215

RESUMEN

Malaria, one of the major infectious diseases in the world, is caused by the Plasmodium parasite. Plasmodium antigens could modulate the inflammatory response by binding to macrophage membrane receptors. As an export protein on the infected erythrocyte membrane, Plasmodium surface-related antigen (SRA) participates in the erythrocyte invasion and regulates the immune response of the host. This study found that the F2 segment of P. yoelii SRA activated downstream MAPK and NF-κB signaling pathways by binding to CD68 on the surface of the macrophage membrane and regulating the inflammatory response. The anti-PySRA-F2 antibody can protect mice against P. yoelii, and the pro-inflammatory responses such as IL-1ß, TNF-α, and IL-6 after infection with P. yoelii are attenuated. These findings will be helpful for understanding the involvement of the pathogenic mechanism of malaria with the exported protein SRA.


Asunto(s)
Antígenos CD , Antígenos de Protozoos , Macrófagos , Malaria , Plasmodium yoelii , Animales , Femenino , Humanos , Ratones , Antígenos CD/metabolismo , Antígenos CD/inmunología , Antígenos de Diferenciación Mielomonocítica/metabolismo , Antígenos de Diferenciación Mielomonocítica/inmunología , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/metabolismo , Antígenos de Superficie/inmunología , Antígenos de Superficie/metabolismo , Membrana Celular/metabolismo , Membrana Celular/inmunología , Inflamación/inmunología , Inflamación/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/parasitología , Malaria/inmunología , Malaria/parasitología , FN-kappa B/metabolismo , FN-kappa B/inmunología , Plasmodium yoelii/inmunología , Unión Proteica , Transducción de Señal
5.
Blood ; 139(13): 1939-1953, 2022 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-35015835

RESUMEN

Understanding the biological and clinical impact of copy number aberrations (CNAs) on the development of precision therapies in cancer remains an unmet challenge. Genetic amplification of chromosome 1q (chr1q-amp) is a major CNA conferring an adverse prognosis in several types of cancer, including in the blood cancer multiple myeloma (MM). Although several genes across chromosome 1 (chr1q) portend high-risk MM disease, the underpinning molecular etiology remains elusive. Here, with reference to the 3-dimensional (3D) chromatin structure, we integrate multi-omics data sets from patients with MM with genetic variables to obtain an associated clinical risk map across chr1q and to identify 103 adverse prognosis genes in chr1q-amp MM. Prominent among these genes, the transcription factor PBX1 is ectopically expressed by genetic amplification and epigenetic activation of its own preserved 3D regulatory domain. By binding to reprogrammed superenhancers, PBX1 directly regulates critical oncogenic pathways and a FOXM1-dependent transcriptional program. Together, PBX1 and FOXM1 activate a proliferative gene signature that predicts adverse prognosis across multiple types of cancer. Notably, pharmacological disruption of the PBX1-FOXM1 axis with existing agents (thiostrepton) and a novel PBX1 small molecule inhibitor (T417) is selectively toxic against chr1q-amp myeloma and solid tumor cells. Overall, our systems medicine approach successfully identifies CNA-driven oncogenic circuitries, links them to clinical phenotypes, and proposes novel CNA-targeted therapy strategies in MM and other types of cancer.


Asunto(s)
Mieloma Múltiple , Cromosomas Humanos Par 1/metabolismo , Proteína Forkhead Box M1/genética , Humanos , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Factor de Transcripción 1 de la Leucemia de Células Pre-B/genética , Pronóstico , Análisis de Sistemas , Factores de Transcripción/genética
6.
Brain Behav Immun ; 120: 167-180, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38834156

RESUMEN

It is widely believed that the activation of the central dopamine (DA) system is crucial to the rewarding effects of methamphetamine (METH) and to the behavioral outcomes of METH use disorder. It was reported that METH exposure induced gasdermin D (GSDMD)-dependent pyroptosis in rats. The membrane pore formation caused by METH-induced pyroptosis may also contribute to the overflow of DA into the extracellular space and subsequently increase the DA levels in the brain. The present study firstly investigated whether the membrane pore information induced by GSDMD-dependent pyroptosis was associated with the increased DA levels in the ventral tegmental area (VAT) and nucleus accumbens (NAc) of rats self-administering METH and SY-SH5Y cells treated by METH. Subsequently, the effect of pore formation blockade or genetic inhibition of GSDMD on the reinforcing and motivational effect of METH was determined in rats, using the animal model of METH self-administration (SA). METH exposure significantly increased the activity of NLRP1/Cas-1/GSDMD pathway and the presence of pyroptosis, accompanied by the significantly increased DA levels in VTA and NAc. Moreover, intraperitoneal injections of disulfiram (DSF) or microinjection of rAAV-shGSDMD into VTA/NAc significantly reduced the reinforcing and motivational effect of METH, accompanied by the decreased level of DA in VTA and NAc. The results provided novel evidence that METH-induced pyroptosis could increase DA release in VTA and NAc via the NLRP1/Cas-1/GSDMD pathway. Additionally, membrane pores or GSDMD blockade could significantly reduce the reinforcing and motivational effect of METH. In conclusion, blocking GSDMD and membrane pore formation could be a promising potential target for the development of agents to treat METH use disorder.


Asunto(s)
Dopamina , Metanfetamina , Núcleo Accumbens , Proteínas de Unión a Fosfato , Piroptosis , Autoadministración , Área Tegmental Ventral , Animales , Metanfetamina/farmacología , Metanfetamina/administración & dosificación , Piroptosis/efectos de los fármacos , Masculino , Proteínas de Unión a Fosfato/metabolismo , Ratas , Núcleo Accumbens/metabolismo , Núcleo Accumbens/efectos de los fármacos , Dopamina/metabolismo , Área Tegmental Ventral/metabolismo , Área Tegmental Ventral/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratas Sprague-Dawley , Humanos , Estimulantes del Sistema Nervioso Central/farmacología , Estimulantes del Sistema Nervioso Central/administración & dosificación , Gasderminas
7.
Biomarkers ; 29(6): 384-392, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39234749

RESUMEN

BACKGROUND: Chronic atrophic gastritis (CAG) is an important precursor of gastric cancer(GC), and there is currently a lack of reliable non-invasive diagnostic markers. This study aims to find a biomarker for non-invasive screening of CAG in the community. METHODS: A total of 540 individuals were enrolled (test set = 385, validation set = 155). ROC curve analysis was used to evaluate the diagnostic significance of serum Trefoil Factor 3 (TFF3) alone or in combination with pepsinogen (PG) for CAG in the test and validation set. Furthermore, the diagnostic value of TFF3 and PG in different Helicobacter pylori (H. pylori) infection states was studied. RESULTS: When compared with chronic superficial gastritis (CSG), the expression level of serum TFF3 in the CAG was higher (27 ng/ml vs 19.61, P < 0.001). ROC curve analysis found that the sensitivity, specificity, and area under the curve (AUC) of CAG diagnosis using serum TFF3 alone at the optimal cut-off value of 26.55 ng/ml were 0.529, 0.87, and 0.739, respectively. When TFF3 was combined with The Ratio of PGI to PGII (PGR), the AUC and specificity reached 0.755 and 0.825, respectively. TFF3 individual or combined with PGR had good predictive value, especially in the H. Pylori negative patients. CONCLUSION: TFF3 combined with PGR can effectively predict CAG, especially in patients with H. pylori negative.


Asunto(s)
Gastritis Atrófica , Infecciones por Helicobacter , Pepsinógeno A , Neoplasias Gástricas , Factor Trefoil-3 , Humanos , Gastritis Atrófica/sangre , Gastritis Atrófica/diagnóstico , Factor Trefoil-3/sangre , Pepsinógeno A/sangre , Neoplasias Gástricas/sangre , Neoplasias Gástricas/diagnóstico , Estudios Retrospectivos , Masculino , Femenino , Persona de Mediana Edad , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/sangre , Curva ROC , Helicobacter pylori , Detección Precoz del Cáncer/métodos , Adulto , Anciano , Biomarcadores/sangre , Sensibilidad y Especificidad , Enfermedad Crónica
8.
Inorg Chem ; 63(42): 19964-19971, 2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-39385599

RESUMEN

A B-site ordered double perovskite oxide Cd2CrSbO6 was synthesized under high-pressure and high-temperature conditions. The compound crystallizes to a monoclinic structure with a space group of P21/n. The charge configuration is confirmed to be that of Cd2+/Cr3+/Sb5+. The magnetic Cr3+ ions form a tetrahedral structural frustrated lattice, while a long-range ferromagnetic phase transition is found to occur at TC = 16.5 K arising from the superexchange interaction via the Cr-O-Cd-O-Cr pathway. Electrical transport measurements indicate that Cd2CrSbO6 is an insulator that can be described by the Mott 3D variable range hopping mechanism. First-principles calculations reproduce well the ferromagnetic and insulating ground state of Cd2CrSbO6 with an energy band gap of 1.55 eV. The intrinsic ferromagnetic insulating nature qualifies Cd2CrSbO6 as a promising candidate for possible spintronics applications.

9.
Crit Care ; 28(1): 213, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956604

RESUMEN

BACKGROUND: The multidimensional biological mechanisms underpinning acute respiratory distress syndrome (ARDS) continue to be elucidated, and early biomarkers for predicting ARDS prognosis are yet to be identified. METHODS: We conducted a multicenter observational study, profiling the 4D-DIA proteomics and global metabolomics of serum samples collected from patients at the initial stage of ARDS, alongside samples from both disease control and healthy control groups. We identified 28-day prognosis biomarkers of ARDS in the discovery cohort using the LASSO method, fold change analysis, and the Boruta algorithm. The candidate biomarkers were validated through parallel reaction monitoring (PRM) targeted mass spectrometry in an external validation cohort. Machine learning models were applied to explore the biomarkers of ARDS prognosis. RESULTS: In the discovery cohort, comprising 130 adult ARDS patients (mean age 72.5, 74.6% male), 33 disease controls, and 33 healthy controls, distinct proteomic and metabolic signatures were identified to differentiate ARDS from both control groups. Pathway analysis highlighted the upregulated sphingolipid signaling pathway as a key contributor to the pathological mechanisms underlying ARDS. MAP2K1 emerged as the hub protein, facilitating interactions with various biological functions within this pathway. Additionally, the metabolite sphingosine 1-phosphate (S1P) was closely associated with ARDS and its prognosis. Our research further highlights essential pathways contributing to the deceased ARDS, such as the downregulation of hematopoietic cell lineage and calcium signaling pathways, contrasted with the upregulation of the unfolded protein response and glycolysis. In particular, GAPDH and ENO1, critical enzymes in glycolysis, showed the highest interaction degree in the protein-protein interaction network of ARDS. In the discovery cohort, a panel of 36 proteins was identified as candidate biomarkers, with 8 proteins (VCAM1, LDHB, MSN, FLG2, TAGLN2, LMNA, MBL2, and LBP) demonstrating significant consistency in an independent validation cohort of 183 patients (mean age 72.6 years, 73.2% male), confirmed by PRM assay. The protein-based model exhibited superior predictive accuracy compared to the clinical model in both the discovery cohort (AUC: 0.893 vs. 0.784; Delong test, P < 0.001) and the validation cohort (AUC: 0.802 vs. 0.738; Delong test, P = 0.008). INTERPRETATION: Our multi-omics study demonstrated the potential biological mechanism and therapy targets in ARDS. This study unveiled several novel predictive biomarkers and established a validated prediction model for the poor prognosis of ARDS, offering valuable insights into the prognosis of individuals with ARDS.


Asunto(s)
Biomarcadores , Síndrome de Dificultad Respiratoria , Humanos , Síndrome de Dificultad Respiratoria/sangre , Masculino , Femenino , Anciano , Biomarcadores/sangre , Biomarcadores/análisis , Pronóstico , Persona de Mediana Edad , Proteómica/métodos , Estudios de Cohortes , Anciano de 80 o más Años , Proteínas Sanguíneas/análisis , Metabolómica/métodos , Multiómica
10.
Int J Gynecol Cancer ; 34(11): 1737-1744, 2024 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-39414312

RESUMEN

OBJECTIVE: Increased glutamine metabolism by cancer cells via upregulation of the drug-targetable enzyme glutaminase may contribute to an immune-suppressive tumor microenvironment. Inhibiting glutamine metabolism can not only suppress tumor growth, but also enhance tumor-specific immunity. We investigated the relationship between glutaminase expression, the immune tumor microenvironment, and clinicopathologic features in endometrial cancer. METHODS: Tissue microarrays constructed from 87 primary endometrial cancer specimens were stained by immunohistochemistry for glutaminase, c-Myc, mutL homolog 1 (MLH1), mutS homolog 2 (MSH2), mutS homolog 6 (MSH6), postmeiotic segregation increased 2 (PMS2), estrogen receptor (ER), progresterone receptor (PR), CD8, FoxP3, CD68, programmed cell death protein 1 (PD-1), and programmed cell death ligand 1 (PD-L1). We compared the immune tumor microenvironment and clinicopathologic features between glutaminase-high (H-score≥median) versus glutaminase-low (H-score

Asunto(s)
Neoplasias Endometriales , Glutaminasa , Microambiente Tumoral , Humanos , Femenino , Neoplasias Endometriales/patología , Neoplasias Endometriales/inmunología , Neoplasias Endometriales/enzimología , Glutaminasa/metabolismo , Persona de Mediana Edad , Anciano , Análisis de Matrices Tisulares , Adulto
11.
J Nanobiotechnology ; 22(1): 348, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898486

RESUMEN

Tumor-associated macrophages (TAMs) are a promising target for cancer immunotherapy, but delivering therapeutic agents to TAMs within the tumor microenvironment (TME) is challenging. In this study, a photosensitive, dual-targeting nanoparticle system (M.RGD@Cr-CTS-siYTHDF1 NPs) was developed. The structure includes a shell of DSPE-modified RGD peptides targeting integrin receptors on tumor cells and carboxymethyl mannose targeting CD206 receptors on macrophages, with a core of chitosan adsorbing m6A reading protein YTHDF1 siRNA and chromium nanoparticles (Cr NPs). The approach is specifically designed to target TAM and cancer cells, utilizing the photothermal effect of Cr NPs to disrupt the TME and deliver siYTHDF1 to TAM. In experiments with tumor-bearing mice, M.RGD@Cr-CTS-siYTHDF1 NPs, when exposed to laser irradiation, effectively killed tumor cells, disrupted the TME, delivered siYTHDF1 to TAMs, silenced the YTHDF1 gene, and shifted the STAT3-STAT1 equilibrium by reducing STAT3 and enhancing STAT1 expression. This reprogramming of TAMs towards an anti-tumor phenotype led to a pro-immunogenic TME state. The strategy also suppressed immunosuppressive IL-10 production, increased expression of immunostimulatory factors (IL-12 and IFN-γ), boosted CD8 + T cell infiltration and M1-type TAMs, and reduced Tregs and M2-type TAMs within the TME. In conclusion, the dual-targeting M.RGD@Cr-CTS-siYTHDF1 NPs, integrating dual-targeting capabilities with photothermal therapy (PTT) and RNA interference, offer a promising approach for molecular targeted cancer immunotherapy with potential for clinical application.


Asunto(s)
Inmunoterapia , Neoplasias Hepáticas , ARN Interferente Pequeño , Animales , Ratones , Inmunoterapia/métodos , Humanos , Neoplasias Hepáticas/terapia , Línea Celular Tumoral , Microambiente Tumoral , Macrófagos Asociados a Tumores/metabolismo , Proteínas de Unión al ARN/metabolismo , Nanopartículas/química , Nanopartículas del Metal/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química
12.
J Neurosci ; 42(50): 9435-9449, 2022 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-36323525

RESUMEN

The fetal brains experience rapid and complex development in utero during the second and third trimesters. In utero MRI of the fetal brain in this period enables us to quantify normal fetal brain development in the spatiotemporal domain. In this study, we established a high-quality spatiotemporal atlas between 23 and 38 weeks gestational age (GA) from 90 healthy Chinese human fetuses of both sexes using a pairwise and groupwise registration pipeline. We quantified the fetal cortical morphology indices and characterized their spatiotemporal developmental pattern. The cortical thickness exhibited a biphasic pattern that first increased and then decreased; the curvature fitted well into the Gompertz growth model; sulcal depth increased linearly, while surface area expanded exponentially. The cortical thickness and curvature trajectories consistently pointed to a characteristic time point around GA of 31 weeks. The characteristic GA and growth rate obtained from individual cortical regions suggested a central-to-peripheral developmental gradient, with the earliest development in the parietal lobe, and we also observed a superior-to-inferior gradient within the temporal lobe. These findings may be linked to biophysical events, such as dendritic arborization and thalamocortical fibers ingrowth. The proposed atlas was also compared with an existing fetal atlas from a white/mixed population. Finally, we examined the structural asymmetry of the fetal brains and found extensive asymmetry that dynamically changed with development. The current study depicted a comprehensive profile of fetal cortical development, and the established atlas could be used as a normative reference for neurodevelopmental and diagnostic purposes, especially in the Chinese population.SIGNIFICANCE STATEMENT We generated a high-quality 4D spatiotemporal atlas of the normal fetal brain development from 23 to 38 gestational weeks in a Chinese population and characterized the spatiotemporal developmental pattern of cortical morphology. According to the cortical development trajectories, the fetal cerebral cortex development follows a central-to-peripheral developmental gradient that may be related to the underlying cellular events. The majority of cortical regions already exhibit significant asymmetry during the fetal period.


Asunto(s)
Feto , Imagen por Resonancia Magnética , Masculino , Femenino , Humanos , Embarazo , Feto/diagnóstico por imagen , Neurogénesis , Encéfalo , Desarrollo Fetal , Corteza Cerebral
13.
Neuroimage ; : 120410, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-39491205

RESUMEN

The development of the cerebral cortex during the fetal period is a complex yet well-coordinated process. MRI-based morphological brain network provides a powerful tool for describing this process at a network level. Due to the challenges of in-utero MRI acquisition and image processing, the fetal morphological brain network has not been established. In this study, utilizing high-resolution in-utero MRI data, we constructed an individual morphometric similarity network for each fetus based on multiple cortical features. The spatiotemporal development of morphological connections was described at the level of edge, node, and lobe, respectively. Based on graph theoretical method, the topology structure of fetal morphological network was characterized. Edge analysis demonstrated an increase of morphological dissimilarity between hemispheres with gestational age, especially for the parietal cortex. The limbic and parieto-occipital regions exhibited the most drastic changes of morphological connections at both the edge and node levels. Between- and within-lobe analysis illustrated that the limbic lobe became more similar to other lobes, while the parietal and occipital lobes became more dissimilar to other lobes. Graph theoretical analysis indicated that the small-world structure of the fetal morphological network appeared as early as 22 weeks and that the network topology exhibited an enhanced integration and reduced segregation during prenatal development. The findings obtained from the preterm-born neonates agreed well with those of the fetuses. In summary, this study fills a gap in prenatal morphological brain network research and provides a piece of important evidence for understanding the normal development of fetal brain connectome during the second-third trimester.

14.
BMC Biotechnol ; 23(1): 49, 2023 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-37940925

RESUMEN

BACKGROUND: A method combining offline techniques and the just-in-time learning strategy (JITL) is proposed, because the biochemical reaction process often encounters changing features and parameters over time. METHODS: Firstly, multiple sub-databases in the fermentation process are constructed offline by an improved fuzzy C-means algorithm and the sample data are adaptively pruned by a similarity query threshold. Secondly, an improved eXtreme Gradient Boosting (XGBoost) method is used on the online modeling stage to build soft sensor models, and the multi-similarity-driven just-in-time learning strategy is used to increase the diversity of the model. Finally, to improve the generalization of the whole algorithm, the output of the base learner is fused by an improved Stacking integration model and then the predictive output is performed. RESULTS: Applying the constructed soft sensor model to the problem of predicting cell concentration and product concentration in Pichia pastoris fermentation process. The experimental results show that the root mean square error of the cell concentration is 0.0260, the coefficient of determination is 0.9945, the root mean square error of the product concentration is 2.6688, and the coefficient of determination is 0.9970. It shows that the proposed method has the advantages of timely prediction and high prediction accuracy, which validates the effectiveness and practicality of the method. CONCLUSION: The JS-ISSA-XGBoost is an extensive and excellent soft measurement model that meets the practical needs for real-time monitoring of parameters and prediction of control in biochemical reactions.


Asunto(s)
Algoritmos , Bases de Datos Factuales , Fermentación
15.
Respir Res ; 24(1): 297, 2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-38007424

RESUMEN

BACKGROUND: Chronic obstructive pulmonary disease (COPD), a chronic inflammatory lung disease, is a leading cause of morbidity and mortality worldwide. Prolonged cigarette smoking (CS) that causes irreversible airway remodeling and significantly reduces lung function is a major risk factor for COPD. Keratin15+ (Krt15+) cells with the potential of self-renewal and differentiation properties have been implicated in the maintenance, proliferation, and differentiation of airway basal cells; however, the role of Krt15 in COPD is not clear. METHODS: Krt15 knockout (Krt15-/-) and wild-type (WT) mice of C57BL/6 background were exposed to CS for six months to establish COPD models. Krt15-CrePGR;Rosa26-LSL-tdTomato mice were used to trace the fate of the Krt15+ cells. Hematoxylin and eosin (H&E) and Masson stainings were performed to assess histopathology and fibrosis, respectively. Furthermore, lentivirus-delivered short hairpin RNA (shRNA) was used to knock down KRT15 in human bronchial epithelial (HBE) cells stimulated with cigarette smoke extract (CSE). The protein expression was assessed using western blot, immunohistochemistry, and enzyme-linked immunosorbent assay. RESULTS: Krt15-/- CS mice developed severe inflammatory cell infiltration, airway remodeling, and emphysema. Moreover, Krt15 knockout aggravated CS-induced secretion of matrix metalloproteinase-9 (MMP-9) and epithelial-mesenchymal transformation (EMT), which was reversed by SB-3CT, an MMP-9 inhibitor. Consistent with this finding, KRT15 knockdown promoted MMP-9 expression and EMT progression in vitro. Furthermore, Krt15+ cells gradually increased in the bronchial epithelial cells and were transformed into alveolar type II (AT2) cells. CONCLUSION: Krt15 regulates the EMT process by promoting MMP-9 expression and protects the lung tissue from CS-induced injury, inflammatory infiltration, and apoptosis. Furthermore, Krt15+ cells transformed into AT2 cells to protect alveoli. These results suggest Krt15 as a potential therapeutic target for COPD.


Asunto(s)
Fumar Cigarrillos , Enfermedad Pulmonar Obstructiva Crónica , Animales , Humanos , Ratones , Remodelación de las Vías Aéreas (Respiratorias) , Fumar Cigarrillos/efectos adversos , Células Epiteliales/metabolismo , Transición Epitelial-Mesenquimal/fisiología , Queratina-15/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones Endogámicos C57BL , Enfermedad Pulmonar Obstructiva Crónica/genética , Enfermedad Pulmonar Obstructiva Crónica/prevención & control , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Nicotiana/toxicidad
16.
Ann Hematol ; 102(7): 1731-1738, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37145324

RESUMEN

Acute myeloid leukaemia (AML) with t (8;21) or inv (16), called core binding factor (CBF) AML, has a favourable prognosis. However, some CBF-AML patients have persistent measurable residual disease (MRD) and are more likely to relapse after standard chemotherapy treatment. The CAG regimen, composed of cytarabine, aclarubicin and granulocyte colony-stimulating factor, has been proven to be effective and safe in treating refractory AML patients. We performed a retrospective study to evaluate the efficacy of the CAG regimen to eliminate MRD detected by RUNX1::RUNX1T1 and CBFß::MYH11 transcript levels by quantitative polymerase chain reaction (Q-PCR) among 23 patients. Molecular response was defined as the ratio of fusion transcript after treatment to that before treatment less than or equal to 0.5. The molecular response rate and median decrease ratio of fusion transcripts at the molecular level of the CAG regimen were 52% and 0.53, respectively. The median fusion transcripts before CAG treatment was 0.25% whereas after CAG was 0.11%. Among the 15 patients who had a poor molecular response to the high/intermediate-dose cytarabine regimen, the median decrease ratios of transcripts at the molecular level of high/intermediate-dose cytarabine and CAG were 1.55 and 0.53 (P = 0.028), respectively, and 6 of 15 patients achieved a molecular response to CAG (40%). The median disease-free survival was 18 months, and the overall survival rate at 3 years among all patients was 72.7% ± 10.7%. The common grades 3-4 adverse events were nausea (100%), thrombocytopenia (39%) and neutropenia (37.5%). The CAG regimen may have activity in CBF-AML patients and could provide a new option for patients who have a poor molecular response to high/intermediate-dose cytarabine.


Asunto(s)
Leucemia Mieloide Aguda , Neutropenia , Humanos , Aclarubicina , Estudios Retrospectivos , Resultado del Tratamiento , Recurrencia Local de Neoplasia/tratamiento farmacológico , Leucemia Mieloide Aguda/tratamiento farmacológico , Citarabina , Neutropenia/inducido químicamente , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Factores de Unión al Sitio Principal
17.
J Org Chem ; 88(13): 8791-8801, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37260330

RESUMEN

A [6 + 1] annulation reaction via cascade 1,6-hydride transfer/cyclization is reported to construct a polycyclic 3,4-fused azepinoindole skeleton. The newly designed 4-amino-indole-3-carbaldehyde is applied as a novel six-atom synthon, interacting with arylamines and malononitrile to achieve the [6 + 1] annulation. Notably, the reaction proceeds smoothly under redox-neutral and metal-free conditions, providing a wide range of azepinoindoles in up to 94% yields, with water as the only byproduct. Besides, the advantage of high step- and atom-economy further highlights the practicality of this methodology.


Asunto(s)
Paladio , Catálisis , Ciclización , Oxidación-Reducción
18.
Org Biomol Chem ; 21(4): 700-714, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36601772

RESUMEN

The use of alkyl amines and ethers as traceless hydride donors in [1,5]-hydride transfer cascade reactions represents a promising strategy that greatly enriches redox-neutral hydride transfer chemistry. This review summarizes the remarkable progress made in this field, and focuses on (1) alkyl amines as traceless hydride donors in cascade [1,5]-hydride transfer/elimination reactions and (2) alkyl ethers as traceless hydride donors in [1,5]-hydride transfer cascade reactions. The reaction mechanisms, features, scope, limitations, and synthetic applications are included, where appropriate. Importantly, its powerful ability in allene synthesis and the combination with [Re]-vinylidene and carbocation chemistries render this strategy attractive enough to inspire chemists to develop colorful reactions for building molecular complexity.

19.
Macromol Rapid Commun ; 44(20): e2300298, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37548089

RESUMEN

This work introduces a novel multifunctional system called UPIPF (upconversion-polydopamine-indocyanine-polyethylene-folic) for upconversion luminescent (UCL) imaging of cancer cells using near-infrared (NIR) illumination. The system demonstrates efficient inhibition of human hepatoma (HepG2) cancer cells through a combination of NIR-triggered photodynamic therapy (PDT) and enhanced photothermal therapy (PTT). Initially, upconversion nanoparticles (UCNP) are synthesized using a simple thermal decomposition method. To improve their biocompatibility and aqueous dispersibility, polydopamine (PDA) is introduced to the UCNP via a ligand exchange technique. Indocyanine green (ICG) molecules are electrostatically attached to the surface of the UCNP-polydopamine (UCNP@PDAs) complex to enhance the PDT and PTT effects. Moreover, polyethylene glycol (PEG)-modified folic acid (FA) is incorporated into the UCNP-polydopamine-indocyanine-green (UCNP@PDA-ICGs) nanoparticles to enhance their targeting capability against cancer cells. The excellent UCL properties of these UCNP enable the final UCNP@PDA-ICG-PEG-FA nanoparticles (referred to as UPIPF) to serve as a potential candidate for efficient anticancer drug delivery, real-time imaging, and early diagnosis of cancer cells. Furthermore, the UPIPF system exhibits PDT-assisted PTT effects, providing a convenient approach for efficient cancer cell inhibition (more than 99% of cells are killed). The prepared UPIPF system shows promise for early diagnosis and simultaneous treatment of malignant cancers.


Asunto(s)
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Verde de Indocianina/farmacología , Verde de Indocianina/uso terapéutico , Indoles/farmacología , Polímeros/farmacología , Polietilenglicoles , Fotoquimioterapia/métodos , Línea Celular Tumoral , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico
20.
BMC Pregnancy Childbirth ; 23(1): 840, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057742

RESUMEN

BACKGROUND: Prior studies have shown that, when administered as an intravenous bolus to prevent uterine atony, prophylactic phenylephrine infusion increased the dose requirement of oxytocin and second-line uterotonics. For the prevention of uterine atony, oxytocin should be delivered by continuous infusion. Here, we aimed to determine the ED50 and ED90 parameters (the effective doses for 50 and 90% patients without uterine atony) of oxytocin for co-infusion with prophylactic phenylephrine during cesarean delivery. METHODS: In this prospective randomized double-blinded dose-finding study, one hundred patients were divided into four groups to receive 2.5, 5.0, 7.5, or 10 IU/h oxytocin infusion, after the umbilical cord was clamped during the study period. The uterine tone was evaluated and defined as either adequate or inadequate. Probit regression analysis was applied to calculate the ED50 and ED90 of oxytocin infusion. Uterine tone, the percentage of patients who needed additional oxytocin bolus, second-line uterotonics, side effects, estimated blood loss, and neonatal outcomes were monitored. RESULTS: The estimated ED50 and ED90 values of the oxytocin infusion doses for the prevention of uterine atony were 1.9 IU/h (95% CI -4.6-3.8) IU/h and 9.3 IU/h (95% CI 7.3-16.2) IU/h, respectively. Across groups, there was a significant linear trend between the infusion dose and the percentage of patients who required additional oxytocin (p-value = 0.002). No differences were observed in the incidence of side effects and neonatal outcomes. CONCLUSION: Under the conditions of this study, the ED90 of oxytocin infusion for the prevention of uterine atony was 9.3 IU/h, which is higher than the current recommendation. This finding is helpful for clinical practice, because of the routine use of phenylephrine in cesarean delivery. Further studies are needed to determine the appropriate initial bolus of oxytocin after neonatal delivery. TRIAL REGISTRATION: The study was registered on the Chinese Clinical Trial Register (register no. ChiCTR2200059556 ).


Asunto(s)
Hipotensión , Oxitócicos , Inercia Uterina , Embarazo , Femenino , Recién Nacido , Humanos , Oxitocina , Fenilefrina , Estudios Prospectivos , Hipotensión/etiología , Hipotensión/prevención & control , Método Doble Ciego , Infusiones Intravenosas
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