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1.
Nature ; 602(7896): 229-233, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35140383

RESUMEN

Ultracold assembly of diatomic molecules has enabled great advances in controlled chemistry, ultracold chemical physics and quantum simulation with molecules1-3. Extending the ultracold association to triatomic molecules will offer many new research opportunities and challenges in these fields. A possible approach is to form triatomic molecules in a mixture of ultracold atoms and diatomic molecules by using a Feshbach resonance between them4,5. Although ultracold atom-diatomic-molecule Feshbach resonances have been observed recently6,7, using these resonances to form triatomic molecules remains challenging. Here we report on evidence of the association of triatomic molecules near the Feshbach resonance between 23Na40K molecules in the rovibrational ground state and 40K atoms. We apply a radio-frequency pulse to drive the free-bound transition in ultracold mixtures of 23Na40K and 40K and monitor the loss of 23Na40K molecules. The association of triatomic molecules manifests itself as an additional loss feature in the radio-frequency spectra, which can be distinguished from the atomic loss feature. The observation that the distance between the association feature and the atomic transition changes with the magnetic field provides strong evidence for the formation of triatomic molecules. The binding energy of the triatomic molecules is estimated from the measurements. Our work contributes to the understanding of the complex ultracold atom-molecule Feshbach resonances and may open up an avenue towards the preparation and control of ultracold triatomic molecules.

2.
Blood ; 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39316647

RESUMEN

Iron regulatory proteins (IRP1 and IRP2) play a pivotal role in maintaining cellular iron homeostasis by binding to iron-responsive elements (IREs) of target mRNAs and regulating the expression of these iron-related genes. Mice and humans that lack functional IRP1 develop erythrocytosis due to erythropoietin overproduction, whereas those that lack IRP2 develop microcytic anemia believed to result from iron deficiency of erythroblasts. Here, we discovered that IRP2 deficiency reduced the expression of hypoxia inducible factor 2 alpha (HIF2a) and its transcriptional target, erythropoietin (EPO), thereby compromising the stress erythropoiesis response to generate RBCs upon anemia. The distinct consequences of IRP2 and IRP1 on EPO result from the higher binding affinity of the HIF2a IRE for IRP1 compared to IRP2. This difference in binding affinity arises from a bulge uridine in the upper stem of HIF2a IRE that impairs the ability of IRP2 to bind the IRE. These results reveal that IRP1 and IRP2 play distinct roles in erythropoiesis and unveil an unsuspected IRE binding preference that contributes to the divergent phenotypes observed in IRP1 and IRP2 deficient mammals.

3.
Proc Natl Acad Sci U S A ; 120(33): e2303860120, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37552760

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, uses an RNA-dependent RNA polymerase along with several accessory factors to replicate its genome and transcribe its genes. Nonstructural protein (nsp) 13 is a helicase required for viral replication. Here, we found that nsp13 ligates iron, in addition to zinc, when purified anoxically. Using inductively coupled plasma mass spectrometry, UV-visible absorption, EPR, and Mössbauer spectroscopies, we characterized nsp13 as an iron-sulfur (Fe-S) protein that ligates an Fe4S4 cluster in the treble-clef metal-binding site of its zinc-binding domain. The Fe-S cluster in nsp13 modulates both its binding to the template RNA and its unwinding activity. Exposure of the protein to the stable nitroxide TEMPOL oxidizes and degrades the cluster and drastically diminishes unwinding activity. Thus, optimal function of nsp13 depends on a labile Fe-S cluster that is potentially targetable for COVID-19 treatment.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Tratamiento Farmacológico de COVID-19 , ADN Helicasas/metabolismo , ARN , Azufre , Proteínas no Estructurales Virales/metabolismo , ARN Helicasas/genética
4.
Proc Natl Acad Sci U S A ; 119(50): e2122494119, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36469777

RESUMEN

Physical interfaces widely exist in nature and engineering. Although the formation of passive interfaces is well elucidated, the physical principles governing active interfaces remain largely unknown. Here, we combine simulation, theory, and cell-based experiment to investigate the evolution of an active-active interface. We adopt a biphasic framework of active nematic liquid crystals. We find that long-lived topological defects mechanically energized by activity display unanticipated dynamics nearby the interface, where defects perform "U-turns" to keep away from the interface, push the interface to develop local fingers, or penetrate the interface to enter the opposite phase, driving interfacial morphogenesis and cross-interface defect transport. We identify that the emergent interfacial morphodynamics stems from the instability of the interface and is further driven by the activity-dependent defect-interface interactions. Experiments of interacting multicellular monolayers with extensile and contractile differences in cell activity have confirmed our predictions. These findings reveal a crucial role of topological defects in active-active interfaces during, for example, boundary formation and tissue competition that underlie organogenesis and clinically relevant disorders.


Asunto(s)
Cristales Líquidos , Cristales Líquidos/química , Simulación por Computador
5.
Eur J Neurosci ; 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39421897

RESUMEN

Attention is one of the basic cognitive functions sensitive to high altitude, and most studies have focussed on exposure times of approximately 3 years; however, it is unclear how attention changes in migrants who have lived and worked at high altitude for nearly 20 years. We explored the dynamics of attentional networks and neurophysiological mechanisms in migrants over 3-20 years using the Attentional Network Test combined with Electrocardiograph and Electroencephalography and found a consistent quadratic correlation between exposure and executive control efficiency, P3 amplitude and heart rate variability (HRV), with a decrease followed by an increase/relative stability, with approximately 10 years being the breakpoint. However, neither linear nor quadratic trajectories were observed for the alerting and orienting network. Mediation analysis revealed that the P3 amplitude mediated the decrease and increase in executive control efficiency with exposure time depends on the breakpoint. Correlations between HRV and executive control efficiency and P3 amplitude suggest that U-shaped changes in executive control in migrants may be related to body homeostasis maintained by the autonomic nervous system, and that P3 amplitude may serve as a neurophysiological marker of migrants' adaptation/recovery from high-altitude exposure.

6.
BMC Med ; 22(1): 206, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769523

RESUMEN

BACKGROUND: Numerous studies have been conducted to investigate the relationship between ABO and Rhesus (Rh) blood groups and various health outcomes. However, a comprehensive evaluation of the robustness of these associations is still lacking. METHODS: We searched PubMed, Web of Science, Embase, Scopus, Cochrane, and several regional databases from their inception until Feb 16, 2024, with the aim of identifying systematic reviews with meta-analyses of observational studies exploring associations between ABO and Rh blood groups and diverse health outcomes. For each association, we calculated the summary effect sizes, corresponding 95% confidence intervals, 95% prediction interval, heterogeneity, small-study effect, and evaluation of excess significance bias. The evidence was evaluated on a grading scale that ranged from convincing (Class I) to weak (Class IV). We assessed the certainty of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation criteria (GRADE). We also evaluated the methodological quality of included studies using the A Measurement Tool to Assess Systematic Reviews (AMSTAR). AMSTAR contains 11 items, which were scored as high (8-11), moderate (4-7), and low (0-3) quality. We have gotten the registration for protocol on the PROSPERO database (CRD42023409547). RESULTS: The current umbrella review included 51 systematic reviews with meta-analysis articles with 270 associations. We re-calculated each association and found only one convincing evidence (Class I) for an association between blood group B and type 2 diabetes mellitus risk compared with the non-B blood group. It had a summary odds ratio of 1.28 (95% confidence interval: 1.17, 1.40), was supported by 6870 cases with small heterogeneity (I2 = 13%) and 95% prediction intervals excluding the null value, and without hints of small-study effects (P for Egger's test > 0.10, but the largest study effect was not more conservative than the summary effect size) or excess of significance (P < 0.10, but the value of observed less than expected). And the article was demonstrated with high methodological quality using AMSTAR (score = 9). According to AMSTAR, 18, 32, and 11 studies were categorized as high, moderate, and low quality, respectively. Nine statistically significant associations reached moderate quality based on GRADE. CONCLUSIONS: Our findings suggest a potential relationship between ABO and Rh blood groups and adverse health outcomes. Particularly the association between blood group B and type 2 diabetes mellitus risk.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Metaanálisis como Asunto , Estudios Observacionales como Asunto , Sistema del Grupo Sanguíneo Rh-Hr , Revisiones Sistemáticas como Asunto , Humanos , Revisiones Sistemáticas como Asunto/métodos , Estudios Observacionales como Asunto/métodos
7.
Brief Bioinform ; 23(2)2022 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35043144

RESUMEN

Predicting the response of cancer patients to a particular treatment is a major goal of modern oncology and an important step toward personalized treatment. In the practical clinics, the clinicians prefer to obtain the most-suited drugs for a particular patient instead of knowing the exact values of drug sensitivity. Instead of predicting the exact value of drug response, we proposed a deep learning-based method, named Siamese Response Deep Factorization Machines (SRDFM) Network, for personalized anti-cancer drug recommendation, which directly ranks the drugs and provides the most effective drugs. A Siamese network (SN), a type of deep learning network that is composed of identical subnetworks that share the same architecture, parameters and weights, was used to measure the relative position (RP) between drugs for each cell line. Through minimizing the difference between the real RP and the predicted RP, an optimal SN model was established to provide the rank for all the candidate drugs. Specifically, the subnetwork in each side of the SN consists of a feature generation level and a predictor construction level. On the feature generation level, both drug property and gene expression, were adopted to build a concatenated feature vector, which even enables the recommendation for newly designed drugs with only chemical property known. Particularly, we developed a response unit here to generate weighted genetic feature vector to simulate the biological interaction mechanism between a specific drug and the genes. For the predictor construction level, we built this level integrating a factorization machine (FM) component with a deep neural network component. The FM can well handle the discrete chemical information and both low-order and high-order feature interactions could be sufficiently learned. Impressively, the SRDFM works well on both single-drug recommendation and synergic drug combination. Experiment result on both single-drug and synergetic drug data sets have shown the efficiency of the SRDFM. The Python implementation for the proposed SRDFM is available at at https://github.com/RanSuLab/SRDFM Contact: ran.su@tju.edu.cn, gbx@mju.edu.cn and weileyi@sdu.edu.cn.


Asunto(s)
Antineoplásicos , Neoplasias , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Redes Neurales de la Computación
8.
J Transl Med ; 22(1): 41, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200523

RESUMEN

As more is learned about lactate, it acts as both a product and a substrate and functions as a shuttle system between different cell populations to provide the energy for sustaining tumor growth and proliferation. Recent discoveries of protein lactylation modification mediated by lactate play an increasingly significant role in human health (e.g., neural and osteogenic differentiation and maturation) and diseases (e.g., tumors, fibrosis and inflammation, etc.). These views are critically significant and first described in detail in this review. Hence, here, we focused on a new target, protein lactylation, which may be a "double-edged sword" of human health and diseases. The main purpose of this review was to describe how protein lactylation acts in multiple physiological and pathological processes and their potential mechanisms through an in-depth summary of preclinical in vitro and in vivo studies. Our work aims to provide new ideas for treating different diseases and accelerate translation from bench to bedside.


Asunto(s)
Ácido Láctico , Osteogénesis , Humanos , Diferenciación Celular , Inflamación , Procesamiento Proteico-Postraduccional
9.
Phys Rev Lett ; 132(13): 133603, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613308

RESUMEN

An integrated quantum light source is increasingly desirable in large-scale quantum information processing. Despite recent remarkable advances, a new material platform is constantly being explored for the fully on-chip integration of quantum light generation, active and passive manipulation, and detection. Here, for the first time, we demonstrate a gallium nitride (GaN) microring based quantum light generation in the telecom C-band, which has potential toward the monolithic integration of quantum light source. In our demonstration, the GaN microring has a free spectral range of 330 GHz and a near-zero anomalous dispersion region of over 100 nm. The generation of energy-time entangled photon pair is demonstrated with a typical raw two-photon interference visibility of 95.5±6.5%, which is further configured to generate a heralded single photon with a typical heralded second-order autocorrelation g_{H}^{(2)}(0) of 0.045±0.001. Our results pave the way for developing a chip-scale quantum photonic circuit.

10.
Cell Commun Signal ; 22(1): 404, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160548

RESUMEN

SUMOylation, a post-translational modification involving the covalent attachment of small ubiquitin-like modifier (SUMO) proteins to target substrates, plays a pivotal role at the intersection of gut health and disease, influencing various aspects of intestinal physiology and pathology. This review provides a comprehensive examination of SUMOylation's diverse roles within the gut microenvironment. We examine its critical roles in maintaining epithelial barrier integrity, regulating immune responses, and mediating host-microbe interactions, thereby highlighting the complex molecular mechanisms that underpin gut homeostasis. Furthermore, we explore the impact of SUMOylation dysregulation in various intestinal disorders, including inflammatory bowel diseases and colorectal cancer, highlighting its implications as a potential diagnostic biomarker and therapeutic target. By integrating current research findings, this review offers valuable insights into the dynamic interplay between SUMOylation and gut health, paving the way for novel therapeutic strategies aimed at restoring intestinal equilibrium and combating associated pathologies.


Asunto(s)
Sumoilación , Humanos , Animales , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología
11.
Physiol Plant ; 176(2): e14288, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38644531

RESUMEN

Heat shock protein 20 (Hsp20) is a small molecule heat shock protein that plays an important role in plant growth, development, and stress resistance. Little is known about the function of Hsp20 family genes in apple (Malus domestica). Here, we performed a genome-wide analysis of the apple Hsp20 gene family, and a total of 49 Hsp20s genes were identified from the apple genome. Phylogenetic analysis revealed that the 49 genes were divided into 11 subfamilies, and MdHsp18.2b, a member located in the CI branch, was selected as a representative member for functional characterization. Treatment with NaCl and Botryosphaeria dothidea (B. dothidea), the causal agent of apple ring rot disease, significantly induced MdHsp18.2b transcription level. Further analysis revealed that overexpressing MdHsp18.2b reduced the resistance to salt stress but enhanced the resistance to B. dothidea infection in apple calli. Moreover, MdHsp18.2b positively regulated anthocyanin accumulation in apple calli. Physiology assays revealed that MdHsp18.2b promoted H2O2 production, even in the absence of stress factors, which might contribute to its functions in response to NaCl and B. dothidea infection. Hsps usually function as homo- or heterooligomers, and we found that MdHsp18.2b could form a heterodimer with MdHsp17.9a and MdHsp17.5, two members from the same branch with MdHsp18.2b in the phylogenetic tree. Therefore, we identified 49 Hsp20s genes from the apple genome and found that MdHsp18.2b was involved in regulating plant resistance to salt stress and B. dothidea infection, as well as in regulating anthocyanin accumulation in apple calli.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Proteínas del Choque Térmico HSP20 , Malus , Filogenia , Enfermedades de las Plantas , Proteínas de Plantas , Malus/genética , Malus/microbiología , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Proteínas del Choque Térmico HSP20/genética , Proteínas del Choque Térmico HSP20/metabolismo , Ascomicetos/fisiología , Ascomicetos/genética , Ascomicetos/patogenicidad , Familia de Multigenes , Resistencia a la Enfermedad/genética , Antocianinas/metabolismo
12.
Bioorg Med Chem ; 112: 117901, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39232465

RESUMEN

Multidrug-resistant (MDR) bacterial infections are becoming a life-threatening issue in public health; therefore, it is urgent to develop novel antibacterial agents for treating infections caused by MDR bacteria. The 20(S)-protopanaxadiol (PPD) derivative 9 was identified as a novel antibacterial hit compound in screening of our small synthetic natural product-like (NPL) library. A series of novel PPD derivatives with heterocyclic rings fused at the C-2 and C-3 positions of the A-ring were synthesized and their antibacterial activities against Staphylococcus aureus (S. aureus) Newman strain and MDR S. aureus strains (USA300, NRS-1, NRS-70, NRS-100, NRS-108, NRS-271, XJ017, and XJ036) were evaluated. Among these compounds, quinoxaline derivative 56 (SH617) exhibited the highest activity with MICs of 0.5-4 µg/mL against the S. aureus Newman strain and the eight MDR S. aureus strains. Its antibacterial activity was comparable to that of the positive control, vancomycin. In the zebrafish, 56 revealed no obvious toxicity even at a high administered dose. In vivo, following a lethal infection induced by USA300 strains in zebrafish, 56 exhibited significantly increased survival rates in a dose-dependent manner.


Asunto(s)
Antibacterianos , Pruebas de Sensibilidad Microbiana , Sapogeninas , Staphylococcus aureus , Pez Cebra , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Sapogeninas/farmacología , Sapogeninas/química , Sapogeninas/síntesis química , Staphylococcus aureus/efectos de los fármacos , Animales , Relación Estructura-Actividad , Estructura Molecular , Relación Dosis-Respuesta a Droga , Compuestos Heterocíclicos/farmacología , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/síntesis química
13.
J Nat Prod ; 87(7): 1754-1762, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-38982404

RESUMEN

Sesquiterpene dimers are mainly found in the Asteraceae family. However, conflicting reports on the structures of these compounds can be found in the literature. Herein, we describe ten sesquiterpene dimers isolated from the flowers of Inula japonica, including configurational revisions of japonicone H (1-1), japonicone D (2-1), inulanolide A (4-1), japonicone X (5-1), and inulanolide F (5-2) to compounds 1, 2, 4, and 5, respectively. Five new related metabolites (3 and 6-9) are also described. Application of GIAO NMR/DP4+ analyses and ECD/OR calculations enabled us to revise the absolute configurations of an additional 13 sesquiterpene dimers isolated from plants of the genus Inula. Compounds 1, 2, 4, and 6 exhibited inhibition of nitric oxide production in lipopolysaccharide activated RAW264.7 macrophages with IC50 values of 4.07-10.00 µM.


Asunto(s)
Flores , Inula , Óxido Nítrico , Sesquiterpenos , Flores/química , Sesquiterpenos/farmacología , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Inula/química , Ratones , Animales , Células RAW 264.7 , Estructura Molecular , Óxido Nítrico/biosíntesis , Óxido Nítrico/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Dimerización
14.
Mediators Inflamm ; 2024: 6618927, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39421730

RESUMEN

Background: Baicalein has been used to treat inflammation-related diseases; nevertheless, its specific mechanism of action is unclear. Therefore, we examined the protective effects of baicalein on lipopolysaccharide-induced damage to AR42J pancreatic acinar cells (PACs) and determined its mechanism of action for protection. Methods: An in vitro cell model of acute pancreatitis (AP) was established using lipopolysaccharide (LPS) (1 mg/L)-induced PACs (AR42J), and the relative survival rate was determined using the 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide (MTT) technique. Flow cytometry was applied to evaluate the apoptotic rates of AR42J PACs. The RNA and protein expression of miR-224-5p, poly ADP-ribose polymerase-1 (PARP1), nuclear transcription factor-κB65 (NF-κB65), phospho-kappa B alpha(p-IκB-α), interleukin(IL)-18R, NOD-like receptor thermal protein domain-associated protein 3 (NLRP3), gasdermin D (GSDMD), apoptosis-associated speck-like protein containing a CARD (ASC), and caspase-1 was detected based on the WB and RT-PCR assays. IL-1ß, IL-6, IL-18, and TNF-α expression levels in AR42J cells were measured via ELISA method. The cell morphology was examined using the AO/EB method. Results: The experiment confirmed a significant increase in the activity of AR42J cells treated with various doses of baicalein. Moreover, IL-1ß, IL-6, TNF-α, and IL-18 expression levels in AR42J cells were dramatically reduced (P < 0.05), while miR-224-5p level was obviously enhanced. The protein and gene expression of PARP1, NF-κB65, p-IκB-α, IL-18R, GSDMD, ASC, NLRP3, and caspase-1 was obviously decreased (P < 0.05). Apoptosis in AR42J cells was significantly reduced with significant improvement in cell morphology. Conclusion: Baicalein may significantly alleviate LPS-induced AR42J PAC damage by inhibiting the inflammatory response and pyroptosis. Its mode of action might be linked to higher miR-224-5p expression, which inhibits the PARP1/NF-κB and NLPR3/ASC/caspase-1/GSDMD pathways.


Asunto(s)
Flavanonas , Inflamación , Lipopolisacáridos , MicroARNs , Poli(ADP-Ribosa) Polimerasa-1 , Piroptosis , Piroptosis/efectos de los fármacos , Flavanonas/farmacología , Flavanonas/uso terapéutico , Animales , MicroARNs/metabolismo , MicroARNs/genética , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Ratas , Inflamación/metabolismo , Inflamación/tratamiento farmacológico , Línea Celular , Apoptosis/efectos de los fármacos , Células Acinares/metabolismo , Células Acinares/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , FN-kappa B/metabolismo
15.
Mikrochim Acta ; 191(3): 158, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38409501

RESUMEN

An ultrasensitive surface-enhanced Raman spectroscopy (SERS) aptamer sensor (aptasensor) using a noble metal nanoparticle-magnetic nanospheres composite was developed for L-theanine detection. It makes use of Fe3O4@Au MNPs and Au@Ag NPs embedded with the Raman reporter 4-mercaptobenzoic acid (4MBA). Au@4MBA@Ag NPs modified by aptamer and Fe3O4@Au MNPs modified by cDNA created the aptasensor with the strongest Raman signal of 4MBA through the specific binding of the aptamer. With the preferred binding of L-theanine aptamer to L-theanine, Au@4MBA@Ag NPs were released from Fe3O4@Au MNPs, causing a linear decrease in SERS intensity to achieve the SERS detection of the L-theanine. The SERS peak of 4MBA at 1078 cm-1 was used for quantitative determination. SERS intensity showed a good log-linear relationship within the range 10-10 to 10-6 M of L-theanine. The aptasensor has a high selectivity for L-theanine compared with other twelve tested analytes. Hence, this aptasensor is a promising analytical tool for L-theanine detection. The developed method was applied to the analysis of real samples, demonstrating excellent performance. The comparison with the standard liquid chromatography mass spectrometry method showed an error within 20%.

16.
Int J Mol Sci ; 25(9)2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38732071

RESUMEN

Iron regulatory proteins (IRP1 and IRP2) are the master regulators of mammalian iron homeostasis. They bind to the iron-responsive elements (IREs) of the transcripts of iron-related genes to regulate their expression, thereby maintaining cellular iron availability. The primary method to measure the IRE-binding activity of IRPs is the electrophoresis mobility shift assay (EMSA). This method is particularly useful for evaluating IRP1 activity, since IRP1 is a bifunctional enzyme and its protein levels remain similar during conversion between the IRE-binding protein and cytosolic aconitase forms. Here, we exploited a method of using a biotinylated-IRE probe to separate IRE-binding IRPs followed by immunoblotting to analyze the IRE-binding activity. This method allows for the successful measurement of IRP activity in cultured cells and mouse tissues under various iron conditions. By separating IRE-binding IRPs from the rest of the lysates, this method increases the specificity of IRP antibodies and verifies whether a band represents an IRP, thereby revealing some previously unrecognized information about IRPs. With this method, we showed that the S711-phosphorylated IRP1 was found only in the IRE-binding form in PMA-treated Hep3B cells. Second, we found a truncated IRE-binding IRP2 isoform that is generated by proteolytic cleavage on sites in the 73aa insert region of the IRP2 protein. Third, we found that higher levels of SDS, compared to 1-2% SDS in regular loading buffer, could dramatically increase the band intensity of IRPs in immunoblots, especially in HL-60 cells. Fourth, we found that the addition of SDS or LDS to cell lysates activated protein degradation at 37 °C or room temperature, especially in HL-60 cell lysates. As this method is more practical, sensitive, and cost-effective, we believe that its application will enhance future research on iron regulation and metabolism.


Asunto(s)
Proteína 1 Reguladora de Hierro , Hierro , Humanos , Animales , Hierro/metabolismo , Proteína 1 Reguladora de Hierro/metabolismo , Proteína 1 Reguladora de Hierro/genética , Ratones , Proteína 2 Reguladora de Hierro/metabolismo , Proteína 2 Reguladora de Hierro/genética , Biotinilación , Elementos de Respuesta , Fosforilación , Proteínas Reguladoras del Hierro/metabolismo , Proteínas Reguladoras del Hierro/genética , Unión Proteica , Línea Celular Tumoral
17.
J Environ Manage ; 353: 120157, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38295639

RESUMEN

Nanoscale zerovalent iron (Fe0)-based materials have been demonstrated to be a effective method for the U(VI) removal. However, limited research has been conducted on the long-term immobilization efficiency and mechanism of Fe0-based materials for U(VI), which are essential for achieving safe handling and disposal of U(VI) on a large scale. In this study, the prepared carboxymethyl cellulose (CMC) and sulfurization dual stabilized Fe0 (CMC-Fe0/FeS) exhibited excellent long-term immobilization performances for U(VI) under both anoxic and oxic conditions, with the immobilization efficiencies were respectively reached over 98.0 % and 94.8 % after 180 days of aging. Most importantly, different from the immobilization mechanisms of the fresh CMC-Fe0/FeS for U(VI) (the adsorption effect of -COOH and -OH groups, coordination effect with sulfur species, as well as reduction effect of Fe0), the re-mobilized U(VI) were finally re-immobilized by the formed FeOOH and Fe3O4 on the aged CMC-Fe0/FeS. Under anoxic conditions, more Fe3O4 was produced, which may be the main reason for the long-term immobilization U(VI). Under oxic conditions, the production of Fe3O4 and FeOOH were relatively high, which both played significant roles in re-immobilizing U(VI) through surface complexation, reduction and incorporation effects.


Asunto(s)
Uranio , Carboximetilcelulosa de Sodio , Hierro , Adsorción
18.
Molecules ; 29(15)2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39124954

RESUMEN

As a Pt-group element, Pd has been regarded as one of the alternatives to Pt-based catalysts for the hydrogen evolution reaction (HER). Herein, we performed density functional theory (DFT) computations to explore the most stable structures of PdxBy (x = 6, 19, 44), revealed the in situ structural reconstruction of these clusters under acidic conditions, and evaluated their HER activity. We found that the presence of B can prevent underpotential hydrogen adsorption and activate the H atoms on the cluster surface for the HER. The theoretical calculations show that the reaction barrier for the HER on ~1 nm sized Pd44B4 can be as low as 0.36 eV, which is even lower than for the same-sized Pt and Pd2B nanoparticles. The ultra-high HER activity of sub-nanosized PdxBy clusters makes them a potential new and efficient HER electro-catalyst. This study provides new ideas for evaluating and designing novel nanocatalysts based on the structural reconstruction of small-sized nanoparticles in the future.

19.
Pak J Med Sci ; 40(9): 2085-2089, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39416641

RESUMEN

Objective: To investigate the clinical efficacy of 3D-printed fusion cage implantation in treating cervical spondylotic myelopathy. Methods: A retrospective analysis was performed on 52 patients with single-segment cervical spondylotic myelopathy who received anterior cervical discectomy and fusion in Affiliated Hospital of Beihua University from July 2019 to July 2022. They were divided into the 3D group and the control group. Afterward, the perioperative indicators were compared between the two groups. Meanwhile, the Japanese Orthopaedic Association (JOA) scores, Visual analogue scale (VAS) and neck disability index (NDI) were recorded pre-operation and one-year post-operation. Evaluate the fusion rate of two group of intervertebral fusion cages. Results: The JOA score and NDI of the two groups of patients were significantly improved compared to pre-operation(P<0.05), and the JOA score, JOA score improvement rate, and NDI of the 3D group were better than the control group (P<0.05), the VAS scores were significantly improved compared to pre-operation(P<0.05), but there was no statistically significant difference between the groups (p >0.05). The intervertebral height, angle, and cervical Cobb angle of the two groups of patients were significantly improved compared to pre-operation (P<0.05), and the improvement of intervertebral height, angle, and cervical Cobb angle in the 3D group was better than the control group(P<0.05). Conclusion: The clinical efficacy of 3D printed intervertebral fusion cage placement in the treatment of cervical spondylotic myelopathy may be reliable, and it would be better than traditional intervertebral fusion cages in maintaining the height, angle, cervical Cobb angle, and fusion rate of the intervertebral space.

20.
Pak J Med Sci ; 40(4): 648-651, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38545002

RESUMEN

Objective: To explore the safety and efficacy of metastatic osteosarcoma treatment with combined sintilimab injection and chemotherapy. Methods: We performed a retrospective analysis of 32 patients with metastatic osteosarcoma admitted to the Affiliated Hospital of Beihua University between January 2019 and June 2020. The sample was divided into an observation group, treated with sintilimab injection combined with chemotherapy (n= 16) and a control group, treated with chemotherapy (n = 16). Clinical efficacy and adverse reactions were compared between the two groups. Results: The overall response rates were 68.75% in the observation group and 31.25% in the control group (p < 0.05). The incidences of adverse reactions were 56.25% in the observation group and 81.25% in the control group. This was not a significant difference. In the observation group, the progression-free survival time was 8.13 ± 2.50 months, and the overall survival time was 22.75 ± 4.95 months. These were both significantly longer than the respective 6.44 ± 1.93 months and 19.69 ± 2.68 months in the control group (p < 0.05). Conclusion: The treatment of metastatic osteosarcoma with combined sintilimab injection and chemotherapy was found to prolong progression-free survival and overall survival time without increasing the incidence of adverse reactions.

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