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1.
Nature ; 622(7984): 754-760, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37730999

RESUMEN

Single-atom catalysts (SACs) have well-defined active sites, making them of potential interest for organic synthesis1-4. However, the architecture of these mononuclear metal species stabilized on solid supports may not be optimal for catalysing complex molecular transformations owing to restricted spatial environment and electronic quantum states5,6. Here we report a class of heterogeneous geminal-atom catalysts (GACs), which pair single-atom sites in specific coordination and spatial proximity. Regularly separated nitrogen anchoring groups with delocalized π-bonding nature in a polymeric carbon nitride (PCN) host7 permit the coordination of Cu geminal sites with a ground-state separation of about 4 Å at high metal density8. The adaptable coordination of individual Cu sites in GACs enables a cooperative bridge-coupling pathway through dynamic Cu-Cu bonding for diverse C-X (X = C, N, O, S) cross-couplings with a low activation barrier. In situ characterization and quantum-theoretical studies show that such a dynamic process for cross-coupling is triggered by the adsorption of two different reactants at geminal metal sites, rendering homo-coupling unfeasible. These intrinsic advantages of GACs enable the assembly of heterocycles with several coordination sites, sterically congested scaffolds and pharmaceuticals with highly specific and stable activity. Scale-up experiments and translation to continuous flow suggest broad applicability for the manufacturing of fine chemicals.

2.
Nature ; 608(7924): 795-802, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35978189

RESUMEN

Although p53 inactivation promotes genomic instability1 and presents a route to malignancy for more than half of all human cancers2,3, the patterns through which heterogenous TP53 (encoding human p53) mutant genomes emerge and influence tumorigenesis remain poorly understood. Here, in a mouse model of pancreatic ductal adenocarcinoma that reports sporadic p53 loss of heterozygosity before cancer onset, we find that malignant properties enabled by p53 inactivation are acquired through a predictable pattern of genome evolution. Single-cell sequencing and in situ genotyping of cells from the point of p53 inactivation through progression to frank cancer reveal that this deterministic behaviour involves four sequential phases-Trp53 (encoding mouse p53) loss of heterozygosity, accumulation of deletions, genome doubling, and the emergence of gains and amplifications-each associated with specific histological stages across the premalignant and malignant spectrum. Despite rampant heterogeneity, the deletion events that follow p53 inactivation target functionally relevant pathways that can shape genomic evolution and remain fixed as homogenous events in diverse malignant populations. Thus, loss of p53-the 'guardian of the genome'-is not merely a gateway to genetic chaos but, rather, can enable deterministic patterns of genome evolution that may point to new strategies for the treatment of TP53-mutant tumours.


Asunto(s)
Carcinogénesis , Progresión de la Enfermedad , Genes p53 , Genoma , Pérdida de Heterocigocidad , Neoplasias Pancreáticas , Proteína p53 Supresora de Tumor , Adenocarcinoma/genética , Adenocarcinoma/patología , Animales , Carcinogénesis/genética , Carcinogénesis/patología , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Evolución Molecular , Eliminación de Gen , Genes p53/genética , Genoma/genética , Ratones , Modelos Genéticos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Proteína p53 Supresora de Tumor/genética
3.
Proc Natl Acad Sci U S A ; 121(17): e2314590121, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38625938

RESUMEN

Studying heroism in controlled settings presents challenges and ethical controversies due to its association with physical risk. Leveraging virtual reality (VR) technology, we conducted a three-study series with 397 participants from China to investigate heroic actions. Participants unexpectedly witnessed a criminal event in a simulated scenario, allowing observation of their tendency to physically intercept a thief. We examined situational factors (voluntariness, authority, and risk) and personal variables [gender, impulsivity, empathy, and social value orientation (SVO)] that may influence heroism. Also, the potential association between heroism and social conformity was explored. In terms of situational variables, voluntariness modulated participants' tendency to intercept the escaping thief, while perceived risk demonstrated its impact by interacting with gender. That is, in study 3 where the perceived risk was expected to be higher (as supported by an online study 5), males exhibited a greater inclination toward heroic behavior compared to females. Regarding other personal variables, the tendency to engage in heroic behavior decreased as empathy levels rose among males, whereas the opposite trend was observed for females. SVO influenced heroic behavior but without a gender interaction. Finally, an inverse relationship between heroism and social conformity was observed. The robustness of these findings was partly supported by the Chinese sample (but not the international sample) of an online study 4 that provided written descriptions of VR scenarios, indicating cultural variations. These results advance insights into motivational factors influencing heroism in the context of restoring order and highlight the power of VR technology in examining social psychological hypotheses beyond ethical constraints.


Asunto(s)
Coraje , Masculino , Femenino , Humanos , Empatía , China
4.
Immunity ; 47(6): 1114-1128.e6, 2017 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-29221730

RESUMEN

CD4+ T cells orchestrate immune responses and destruction of allogeneic organ transplants, but how this process is regulated on a transcriptional level remains unclear. Here, we demonstrated that interferon regulatory factor 4 (IRF4) was a key transcriptional determinant controlling T cell responses during transplantation. IRF4 deletion in mice resulted in progressive establishment of CD4+ T cell dysfunction and long-term allograft survival. Mechanistically, IRF4 repressed PD-1, Helios, and other molecules associated with T cell dysfunction. In the absence of IRF4, chromatin accessibility and binding of Helios at PD-1 cis-regulatory elements were increased, resulting in enhanced PD-1 expression and CD4+ T cell dysfunction. The dysfunctional state of Irf4-deficient T cells was initially reversible by PD-1 ligand blockade, but it progressively developed into an irreversible state. Hence, IRF4 controls a core regulatory circuit of CD4+ T cell dysfunction, and targeting IRF4 represents a potential therapeutic strategy for achieving transplant acceptance.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Rechazo de Injerto/inmunología , Supervivencia de Injerto , Trasplante de Corazón , Factores Reguladores del Interferón/inmunología , Animales , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Diferenciación Celular , Movimiento Celular , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/inmunología , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Rechazo de Injerto/genética , Rechazo de Injerto/mortalidad , Rechazo de Injerto/patología , Granzimas/genética , Granzimas/inmunología , Factores Reguladores del Interferón/deficiencia , Factores Reguladores del Interferón/genética , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-17/genética , Interleucina-17/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Citotóxicas Formadoras de Poros/inmunología , Receptor de Muerte Celular Programada 1/genética , Receptor de Muerte Celular Programada 1/inmunología , Transducción de Señal , Análisis de Supervivencia , Factores de Transcripción/genética , Factores de Transcripción/inmunología , Trasplante Homólogo
5.
Nature ; 586(7830): 549-554, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32906144

RESUMEN

Metal-organic frameworks (MOFs)1-3 are known for their specific interactions with gas molecules4,5; this, combined with their rich and ordered porosity, makes them promising candidates for the photocatalytic conversion of gas molecules to useful products6. However, attempts to use MOFs or MOF-based composites for CO2 photoreduction6-13 usually result in far lower CO2 conversion efficiency than that obtained from state-of-the-art solid-state or molecular catalysts14-18, even when facilitated by sacrificial reagents. Here we create 'molecular compartments' inside MOF crystals by growing TiO2 inside different pores of a chromium terephthalate-based MOF (MIL-101) and its derivatives. This allows for synergy between the light-absorbing/electron-generating TiO2 units and the catalytic metal clusters in the backbones of MOFs, and therefore facilitates photocatalytic CO2 reduction, concurrent with production of O2. An apparent quantum efficiency for CO2 photoreduction of 11.3 per cent at a wavelength of 350 nanometres is observed in a composite that consists of 42 per cent TiO2 in a MIL-101 derivative, namely, 42%-TiO2-in-MIL-101-Cr-NO2. TiO2 units in one type of compartment in this composite are estimated to be 44 times more active than those in the other type, underlining the role of precise positioning of TiO2 in this system.

6.
Proc Natl Acad Sci U S A ; 120(42): e2308496120, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37812720

RESUMEN

Human diseases involve metabolic alterations. Metabolomic profiles have served as a vital biomarker for the early identification of high-risk individuals and disease prevention. However, current approaches can only characterize individual key metabolites, without taking into account the reality that complex diseases are multifactorial, dynamic, heterogeneous, and interdependent. Here, we leverage a statistical physics model to combine all metabolites into bidirectional, signed, and weighted interaction networks and trace how the flow of information from one metabolite to the next causes changes in health state. Viewing a disease outcome as the consequence of complex interactions among its interconnected components (metabolites), we integrate concepts from ecosystem theory and evolutionary game theory to model how the health state-dependent alteration of a metabolite is shaped by its intrinsic properties and through extrinsic influences from its conspecifics. We code intrinsic contributions as nodes and extrinsic contributions as edges into quantitative networks and implement GLMY homology theory to analyze and interpret the topological change of health state from symbiosis to dysbiosis and vice versa. The application of this model to real data allows us to identify several hub metabolites and their interaction webs, which play a part in the formation of inflammatory bowel diseases. The findings by our model could provide important information on drug design to treat these diseases and beyond.


Asunto(s)
Ecosistema , Metabolómica , Humanos , Modelos Estadísticos , Biomarcadores/metabolismo , Física
7.
PLoS Genet ; 19(6): e1010746, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37289658

RESUMEN

Pigeons (Columba livia) are among a select few avian species that have developed a specialized reproductive mode wherein the parents produce a 'milk' in their crop to feed newborn squabs. Nonetheless, the transcriptomic dynamics and role in the rapid transition of core crop functions during 'lactation' remain largely unexplored. Here, we generated a de novo pigeon genome assembly to construct a high resolution spatio-temporal transcriptomic landscape of the crop epithelium across the entire breeding stage. This multi-omics analysis identified a set of 'lactation'-related genes involved in lipid and protein metabolism, which contribute to the rapid functional transitions in the crop. Analysis of in situ high-throughput chromatin conformation capture (Hi-C) sequencing revealed extensive reorganization of promoter-enhancer interactions linked to the dynamic expression of these 'lactation'-related genes between stages. Moreover, their expression is spatially localized in specific epithelial layers, and can be correlated with phenotypic changes in the crop. These results illustrate the preferential de novo synthesis of 'milk' lipids and proteins in the crop, and provides candidate enhancer loci for further investigation of the regulatory elements controlling pigeon 'lactation'.


Asunto(s)
Columbidae , Transcriptoma , Animales , Femenino , Transcriptoma/genética , Columbidae/genética , Columbidae/metabolismo , Perfilación de la Expresión Génica , Leche , Lactancia
8.
Circulation ; 149(20): 1578-1597, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38258575

RESUMEN

BACKGROUND: Calcification of the aortic valve leads to increased leaflet stiffness and consequently results in the development of calcific aortic valve disease (CAVD). However, the underlying molecular and cellular mechanisms of calcification remain unclear. Here, we identified a novel aortic valve calcification-associated PIWI-interacting RNA (piRNA; AVCAPIR) that increases valvular calcification and promotes CAVD progression. METHODS: Using piRNA sequencing, we identified piRNAs contributing to the pathogenesis of CAVD that we termed AVCAPIRs. High-cholesterol diet-fed ApoE-/- mice with AVCAPIR knockout were used to examine the role of AVCAPIR in aortic valve calcification (AVC). Gain- and loss-of-function assays were conducted to determine the role of AVCAPIR in the induced osteogenic differentiation of human valvular interstitial cells. To dissect the mechanisms underlying AVCAPIR-elicited procalcific effects, we performed various analyses, including an RNA pulldown assay followed by liquid chromatography-tandem mass spectrometry, methylated RNA immunoprecipitation sequencing, and RNA sequencing. RNA pulldown and RNA immunoprecipitation assays were used to study piRNA interactions with proteins. RESULTS: We found that AVCAPIR was significantly upregulated during AVC and exhibited potential diagnostic value for CAVD. AVCAPIR deletion markedly ameliorated AVC in high-cholesterol diet-fed ApoE-/- mice, as shown by reduced thickness and calcium deposition in the aortic valve leaflets, improved echocardiographic parameters (decreased peak transvalvular jet velocity and mean transvalvular pressure gradient, as well as increased aortic valve area), and diminished levels of osteogenic markers (Runx2 and Osterix) in aortic valves. These results were confirmed in osteogenic medium-induced human valvular interstitial cells. Using unbiased protein-RNA screening and molecular validation, we found that AVCAPIR directly interacts with FTO (fat mass and obesity-associated protein), subsequently blocking its N6-methyladenosine demethylase activity. Further transcriptomic and N6-methyladenosine modification epitranscriptomic screening followed by molecular validation confirmed that AVCAPIR hindered FTO-mediated demethylation of CD36 mRNA transcripts, thus enhancing CD36 mRNA stability through the N6-methyladenosine reader IGF2BP1 (insulin-like growth factor 2 mRNA binding protein 1). In turn, the AVCAPIR-dependent increase in CD36 stabilizes its binding partner PCSK9 (proprotein convertase subtilisin/kexin type 9), a procalcific gene, at the protein level, which accelerates the progression of AVC. CONCLUSIONS: We identified a novel piRNA that induced AVC through an RNA epigenetic mechanism and provide novel insights into piRNA-directed theranostics in CAVD.


Asunto(s)
Estenosis de la Válvula Aórtica , Válvula Aórtica , Calcinosis , ARN Interferente Pequeño , Animales , Calcinosis/metabolismo , Calcinosis/genética , Calcinosis/patología , Válvula Aórtica/metabolismo , Válvula Aórtica/patología , Válvula Aórtica/anomalías , Humanos , Ratones , Estenosis de la Válvula Aórtica/metabolismo , Estenosis de la Válvula Aórtica/genética , Estenosis de la Válvula Aórtica/patología , ARN Interferente Pequeño/metabolismo , ARN Interferente Pequeño/genética , Masculino , Osteogénesis , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Animales de Enfermedad , Enfermedad de la Válvula Aórtica/metabolismo , Enfermedad de la Válvula Aórtica/genética , Enfermedad de la Válvula Aórtica/patología , ARN de Interacción con Piwi
9.
Hum Mol Genet ; 32(9): 1483-1496, 2023 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-36547263

RESUMEN

Astrocytes and brain endothelial cells are components of the neurovascular unit that comprises the blood-brain barrier (BBB) and their dysfunction contributes to pathogenesis in Huntington's disease (HD). Defining the contribution of these cells to disease can inform cell-type-specific effects and uncover new disease-modifying therapeutic targets. These cells express integrin (ITG) adhesion receptors that anchor the cells to the extracellular matrix (ECM) to maintain the integrity of the BBB. We used HD patient-derived induced pluripotent stem cell (iPSC) modeling to study the ECM-ITG interface in astrocytes and brain microvascular endothelial cells and found ECM-ITG dysregulation in human iPSC-derived cells that may contribute to the dysfunction of the BBB in HD. This disruption has functional consequences since reducing ITG expression in glia in an HD Drosophila model suppressed disease-associated CNS dysfunction. Since ITGs can be targeted therapeutically and manipulating ITG signaling prevents neurodegeneration in other diseases, defining the role of ITGs in HD may provide a novel strategy of intervention to slow CNS pathophysiology to treat HD.


Asunto(s)
Enfermedad de Huntington , Integrinas , Humanos , Integrinas/metabolismo , Células Endoteliales/metabolismo , Enfermedad de Huntington/patología , Neuroglía/metabolismo , Barrera Hematoencefálica/metabolismo , Matriz Extracelular/metabolismo
10.
FASEB J ; 38(10): e23666, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38780091

RESUMEN

Genome-wide association studies have identified many single nucleotide polymorphisms (SNPs) associated with erythrocyte traits. However, the functional variants and their working mechanisms remain largely unknown. Here, we reported that the SNP of rs80207740, which was associated with red blood cell (RBC) volume and hemoglobin content across populations, conferred enhancer activity to XPO7 gene via allele-differentially binding to Ikaros family zinc finger 1 (IKZF1). We showed that the region around rs80207740 was an erythroid-specific enhancer using reporter assays, and that the G-allele further enhanced activity. 3D genome evidence showed that the enhancer interacted with the XPO7 promoter, and eQTL analysis suggested that the G-allele upregulated expression of XPO7. We further showed that the rs80207740-G allele facilitated the binding of transcription factor IKZF1 in EMSA and ChIP analyses. Knockdown of IKZF1 and GATA1 resulted in decreased expression of Xpo7 in both human and mouse erythroid cells. Finally, we constructed Xpo7 knockout mouse by CRISPR/Cas9 and observed anemic phenotype with reduced volume and hemoglobin content of RBC, consistent to the effect of rs80207740 on erythrocyte traits. Overall, our study demonstrated that rs80207740 modulated erythroid indices by regulating IKZF1 binding and Xpo7 expression.


Asunto(s)
Alelos , Eritrocitos , Estudio de Asociación del Genoma Completo , Factor de Transcripción Ikaros , Polimorfismo de Nucleótido Simple , Factor de Transcripción Ikaros/genética , Factor de Transcripción Ikaros/metabolismo , Humanos , Animales , Ratones , Eritrocitos/metabolismo , Carioferinas/genética , Carioferinas/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Regiones Promotoras Genéticas
11.
Nucleic Acids Res ; 51(13): e68, 2023 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-37246712

RESUMEN

Ribosome profiling provides quantitative, comprehensive, and high-resolution snapshots of cellular translation by the high-throughput sequencing of short mRNA fragments that are protected by ribosomes from nucleolytic digestion. While the overall principle is simple, the workflow of ribosome profiling experiments is complex and challenging, and typically requires large amounts of sample, limiting its broad applicability. Here, we present a new protocol for ultra-rapid ribosome profiling from low-input samples. It features a robust strategy for sequencing library preparation within one day that employs solid phase purification of reaction intermediates, allowing to reduce the input to as little as 0.1 pmol of ∼30 nt RNA fragments. Hence, it is particularly suited for the analyses of small samples or targeted ribosome profiling. Its high sensitivity and its ease of implementation will foster the generation of higher quality data from small samples, which opens new opportunities in applying ribosome profiling.


Asunto(s)
Perfilado de Ribosomas , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Biosíntesis de Proteínas , Perfilado de Ribosomas/métodos , Ribosomas/genética , Ribosomas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
12.
Circulation ; 148(4): 336-353, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37232170

RESUMEN

BACKGROUND: PCSK9 (proprotein convertase subtilisin/kexin 9), which is mainly secreted by the liver, is not only a therapeutic target for hyperlipidemia and cardiovascular disease, but also has been implicated in the immune regulation of infections and tumors. However, the role of PCSK9 and the liver in heart transplant rejection (HTR) and the underlying mechanisms remain unclear. METHODS: We assessed serum PCSK9 expression in both murine and human recipients during HTR and investigated the effect of PCSK9 ablation on HTR by using global knockout mice and a neutralizing antibody. Moreover, we performed multiorgan histological and transcriptome analyses, and multiomics and single-cell RNA-sequencing studies of the liver during HTR, as well. We further used hepatocyte-specific Pcsk9 knockout mice to investigate whether the liver regulated HTR through PCSK9. Last, we explored the regulatory effect of the PCSK9/CD36 pathway on the phenotype and function of macrophages in vitro and in vivo. RESULTS: Here, we report that murine and human recipients have high serum PCSK9 levels during HTR. PCSK9 ablation prolonged cardiac allograft survival and attenuated the infiltration of inflammatory cells in the graft and the expansion of alloreactive T cells in the spleen. Next, we demonstrated that PCSK9 was mainly produced and significantly upregulated in the recipient liver, which also showed a series of signaling changes, including changes in the TNF-α (tumor necrosis factor α) and IFN-γ (interferon γ) signaling pathways and the bile acid and fatty acid metabolism pathways. We found mechanistically that TNF-α and IFN-γ synergistically promoted PCSK9 expression in hepatocytes through the transcription factor SREBP2 (sterol regulatory element binding protein 2). Moreover, in vitro and in vivo studies indicated that PCSK9 inhibited CD36 expression and fatty acid uptake by macrophages and strengthened the proinflammatory phenotype, which facilitated their ability to promote proliferation and IFN-γ production by donor-reactive T cells. Last, we found that the protective effect of PCSK9 ablation against HTR is dependent on the CD36 pathway in the recipient. CONCLUSIONS: This study reveals a novel mechanism for immune regulation by the liver through the PCSK9/CD36 pathway during HTR, which influences the phenotype and function of macrophages and suggests that the modulation of this pathway may be a potential therapeutic target to prevent HTR.


Asunto(s)
Trasplante de Corazón , Proproteína Convertasa 9 , Humanos , Ratones , Animales , Proproteína Convertasa 9/genética , Proproteína Convertasa 9/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Células Hep G2 , Hígado/metabolismo , Ácidos Grasos/metabolismo , Ratones Noqueados , Trasplante de Corazón/efectos adversos , Receptores de LDL/genética
13.
BMC Genomics ; 25(1): 259, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38454335

RESUMEN

Sugar Will Eventually be Exported Transporter (SWEET) proteins are highly conserved in various organisms and play crucial roles in sugar transport processes. However, SWEET proteins in peanuts, an essential leguminous crop worldwide, remain lacking in systematic characterization. Here, we identified 94 SWEET genes encoding the conservative MtN3/saliva domains in three peanut species, including 47 in Arachis hypogea, 23 in Arachis duranensis, and 24 in Arachis ipaensis. We observed significant variations in the exon-intron structure of these genes, while the motifs and domain structures remained highly conserved. Phylogenetic analysis enabled us to categorize the predicted 286 SWEET proteins from eleven species into seven distinct groups. Whole genome duplication/segment duplication and tandem duplication were the primary mechanisms contributing to the expansion of the total number of SWEET genes. In addition, an investigation of cis-elements in the potential promoter regions and expression profiles across 22 samples uncovered the diverse expression patterns of AhSWEET genes in peanuts. AhSWEET24, with the highest expression level in seeds from A. hypogaea Tifrunner, was observed to be localized on both the plasma membrane and endoplasmic reticulum membrane. Moreover, qRT-PCR results suggested that twelve seed-expressed AhSWEET genes were important in the regulation of seed development across four different peanut varieties. Together, our results provide a foundational basis for future investigations into the functions of SWEET genes in peanuts, especially in the process of seed development.


Asunto(s)
Arachis , Familia de Multigenes , Arachis/genética , Arachis/metabolismo , Filogenia , Semillas , Azúcares/metabolismo , Proteínas de Plantas/metabolismo
14.
J Am Chem Soc ; 146(29): 20323-20332, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38995375

RESUMEN

Addressing the sluggish kinetics in the alkaline hydrogen oxidation reaction (HOR) is a pivotal yet challenging step toward the commercialization of anion-exchange membrane fuel cells (AEMFCs). Here, we have successfully immobilized indium (In) atoms in an orderly fashion into platinum (Pt) nanoparticles supported by reduced graphene oxide (denoted as O-Pt3In/rGO), significantly enhancing alkaline HOR kinetics. We have revealed that the ordered atomic matrix enables uniform and optimized hydrogen binding energy (HBE), hydroxyl binding energy (OHBE), and carbon monoxide binding energy (COBE) across the catalyst. With a mass activity of 2.3066 A mg-1 at an overpotential of 50 mV, over 10 times greater than that of Pt/C, the catalyst also demonstrates admirable CO resistance and stability. Importantly, the AEMFC implementing this catalyst as the anode catalyst has achieved an impressive power output compared to Pt/C. This work not only highlights the significance of constructing ordered oxophilic sites for alkaline HOR but also sheds light on the design of well-structured catalysts for energy conversion.

15.
Int J Cancer ; 155(3): 519-531, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38602070

RESUMEN

Early detection is critical for improving pancreatic cancer prognosis. Our study aims to identify circulating microRNAs (miRNAs) associated with pancreatic cancer risk. The two-stage study used plasma samples collected ≤5 years prior to cancer diagnosis, from case-control studies nested in five prospective cohort studies. The discovery stage included 185 case-control pairs from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Replication stage samples comprised 277 pairs from Shanghai Women's Health Study/Shanghai Men's Health Study, Southern Community Cohort Study, and Multiethnic Cohort Study. Seven hundred and ninety-eight miRNAs were measured using the NanoString nCounter Analysis System. Odds ratios (OR) and 95% confidence intervals (CI) for per 10% change in miRNAs in association with pancreatic cancer risk were derived from conditional logistic regression analysis in discovery and replication studies, separately, and then meta-analyzed. Stratified analysis was conducted by age at diagnosis (<65/≥65 years) and time interval between sample collection and diagnosis (≤2/>2 years). In the discovery stage, 120 risk associated miRNAs were identified at p < .05. Three were validated in the replication stage: hsa-miR-199a-3p/hsa-miR-199b-3p, hsa-miR-767-5p, and hsa-miR-191-5p, with respective ORs (95% CI) being 0.89 (0.84-0.95), 1.08 (1.02-1.13), and 0.90 (0.85-0.95). Five additional miRNAs, hsa-miR-640, hsa-miR-874-5p, hsa-miR-1299, hsa-miR-22-3p, and hsa-miR-449b-5p, were validated among patients diagnosed at ≥65 years, with OR (95% CI) of 1.23 (1.09-1.39), 1.33 (1.16-1.52), 1.25 (1.09-1.43), 1.28 (1.12-1.46), 0.76 (0.65-0.89), and 1.22 (1.07-1.39), respectively. The miRNA targets were enriched in pancreatic carcinogenesis/progression-related pathways. Our study suggests that circulating miRNAs may identify individuals at high risk for pancreatic cancer ≤5 years prior to diagnosis, indicating its potential utility in cancer screening and surveillance.


Asunto(s)
Biomarcadores de Tumor , MicroARN Circulante , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/diagnóstico , Femenino , Masculino , MicroARN Circulante/sangre , MicroARN Circulante/genética , Persona de Mediana Edad , Estudios de Casos y Controles , Anciano , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/sangre , Estudios Prospectivos , Factores de Riesgo , Detección Precoz del Cáncer/métodos , MicroARNs/sangre , MicroARNs/genética , Pronóstico
16.
Antimicrob Agents Chemother ; 68(2): e0059423, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38193669

RESUMEN

Understanding how bacteria evolve resistance to phages has implications for phage-based therapies and microbial evolution. In this study, the susceptibility of 335 Salmonella isolates to the wide host range Salmonella phage BPSELC-1 was tested. Potentially significant gene sets that could confer resistance were identified using bioinformatics approaches based on phage susceptibility phenotypes; more than 90 potential antiphage defense gene sets, including those involved in lipopolysaccharide (LPS) biosynthesis, DNA replication, secretion systems, and respiratory chain, were found. The evolutionary dynamics of Salmonella resistance to phage were assessed through laboratory evolution experiments, which showed that phage-resistant mutants rapidly developed and exhibited genetic heterogeneity. Most representative Salmonella hosts (58.1% of 62) rapidly developed phage resistance within 24 h. All phage-resistant mutant clones exhibited genetic heterogeneity and observed mutations in LPS-related genes (rfaJ and rfaK) as well as other genes such as cellular respiration, transport, and cell replication-related genes. The study also identified potential trade-offs, indicating that bacteria tend to escape fitness trade-offs through multi-site mutations, all tested mutants increased sensitivity to polymyxin B, but this does not always affect their relative fitness or biofilm-forming capacity. Furthermore, complementing the rfaJ mutant gene could partially restore the phage sensitivity of phage-resistant mutants. These results provide insight into the phage resistance mechanisms of Salmonella and the complexity of bacterial evolution resulting from phage predation, which can inform future strategies for phage-based therapies and microbial evolution.


Asunto(s)
Bacteriófagos , Bacteriófagos/genética , Lipopolisacáridos , Salmonella , Mutación , Fenotipo , Bacterias
17.
Anal Chem ; 96(24): 9817-9825, 2024 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-38730304

RESUMEN

Rapidly identifying and quantifying Gram-positive bacteria are crucial to diagnosing and treating bacterial lower respiratory tract infections (LRTIs). This work presents a field-deployable biosensor for detecting Gram-positive bacteria from exhaled breath condensates (EBCs) based on peptidoglycan recognition using an aptamer. Dielectrophoretic force is employed to enrich the bacteria in 10 s without additional equipment or steps. Concurrently, the measurement of the sensor's interfacial capacitance is coupled to quantify the bacteria during the enrichment process. By incorporation of a semiconductor condenser, the whole detection process, including EBC collection, takes about 3 min. This biosensor has a detection limit of 10 CFU/mL, a linear range of up to 105 CFU/mL and a selectivity of 1479:1. It is cost-effective and disposable due to its low cost. The sensor provides a nonstaining, culture-free and PCR-independent solution for noninvasive and real-time diagnosis of Gram-positive bacterial LRTIs.


Asunto(s)
Técnicas Biosensibles , Pruebas Respiratorias , Bacterias Grampositivas , Peptidoglicano , Peptidoglicano/análisis , Peptidoglicano/química , Pruebas Respiratorias/métodos , Bacterias Grampositivas/aislamiento & purificación , Humanos , Límite de Detección , Aptámeros de Nucleótidos/química
18.
Anal Chem ; 96(14): 5499-5508, 2024 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-38547315

RESUMEN

Characterizing the profiles of proteome and metabolome at the single-cell level is of great significance in single-cell multiomic studies. Herein, we proposed a novel strategy called one-shot single-cell proteome and metabolome analysis (scPMA) to acquire the proteome and metabolome information in a single-cell individual in one injection of LC-MS/MS analysis. Based on the scPMA strategy, a total workflow was developed to achieve the single-cell capture, nanoliter-scale sample pretreatment, one-shot LC injection and separation of the enzyme-digested peptides and metabolites, and dual-zone MS/MS detection for proteome and metabolome profiling. Benefiting from the scPMA strategy, we realized dual-omic analysis of single tumor cells, including A549, HeLa, and HepG2 cells with 816, 578, and 293 protein groups and 72, 91, and 148 metabolites quantified on average. A single-cell perspective experiment for investigating the doxorubicin-induced antitumor effects in both the proteome and metabolome aspects was also performed.


Asunto(s)
Proteoma , Espectrometría de Masas en Tándem , Humanos , Proteoma/metabolismo , Cromatografía Liquida , Metaboloma , Células HeLa
19.
Drug Metab Rev ; 56(2): 164-174, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38655747

RESUMEN

Due to legal, political, and cultural changes, the use of cannabis has rapidly increased in recent years. Research has demonstrated that the cannabinoids cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) inhibit and induce cytochrome P450 (CYP450) enzymes. The objective of this review is to evaluate the effect of CBD and THC on the activity of CYP450 enzymes and the implications for drug-drug interactions (DDIs) with psychotropic agents that are CYP substrates. A systematic search was conducted using PubMed, Scopus, Scientific Electronic Library Online (SciELO) and PsychINFO. Search terms included 'cannabidiol', 'tetrahydrocannabinol', and 'cytochrome P450'. A total of seven studies evaluating the interaction of THC and CBD with CYP450 enzymes and psychotropic drugs were included. Both preclinical and clinical studies were included. Results from the included studies indicate that both CBD and THC inhibit several CYP450 enzymes including, but not limited to, CYP1A2, CYP3C19, and CYP2B6. While there are a few known CYP450 enzymes that are induced by THC and CBD, the induction of CYP450 enzymes is an understudied area of research and lacks clinical data. The inhibitory effects observed by CBD and THC on CYP450 enzymes vary in magnitude and may decrease the metabolism of psychotropic agents, cause changes in plasma levels of psychotropic medications, and increase adverse effects. Our findings clearly present interactions between THC and CBD and several CYP450 enzymes, providing clinicians evidence of a high risk of DDIs for patients who consume both cannabis and psychotropic medication. However, more clinical research is necessary before results are applied to clinical settings.


Asunto(s)
Cannabidiol , Sistema Enzimático del Citocromo P-450 , Dronabinol , Interacciones Farmacológicas , Animales , Humanos , Cannabidiol/farmacología , Inhibidores Enzimáticos del Citocromo P-450/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Dronabinol/farmacología , Psicotrópicos/farmacología
20.
Radiology ; 311(1): e230459, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38563669

RESUMEN

Background Microwave ablation (MWA) is currently under preliminary investigation for the treatment of multifocal papillary thyroid carcinoma (PTC) and has shown promising treatment efficacy. Compared with surgical resection (SR), MWA is minimally invasive and could preserve thyroid function. However, a comparative analysis between MWA and SR is warranted to draw definitive conclusions. Purpose To compare MWA and SR for preoperative US-detected T1N0M0 multifocal PTC in terms of overall and 1-, 3-, and 5-year progression-free survival rates and complication rates. Materials and Methods In this retrospective study, 775 patients with preoperative US-detected T1N0M0 multifocal PTC treated with MWA or SR across 10 centers between May 2015 and December 2021 were included. Propensity score matching (PSM) was performed for patients in the MWA and SR groups, followed by comparisons between the two groups. The primary outcomes were overall and 1-, 3-, and 5-year progression-free survival (PFS) rates and complication rates. Results After PSM, 229 patients (median age, 44 years [IQR 36.5-50.5 years]; 179 female) in the MWA group and 453 patients (median age, 45 years [IQR 37-53 years]; 367 female) in the SR group were observed for a median of 20 months (range, 12-74 months) and 26 months (range, 12-64 months), respectively. MWA resulted in less blood loss, shorter incision length, and shorter procedure and hospitalization durations (all P < .001). There was no evidence of differences in overall and 1-, 3-, or 5-year PFS rates (all P > .05) between MWA and SR (5-year rate, 77.2% vs 83.1%; P = .36) groups. Permanent hoarseness (2.2%, P = .05) and hypoparathyroidism (4.0%, P = .005) were encountered only in the SR group. Conclusion There was no evidence of a significant difference in PFS rates between MWA and SR for US-detected multifocal T1N0M0 PTC, and MWA resulted in fewer complications. Therefore, MWA is a feasible option for selected patients with multifocal T1N0M0 PTC. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Georgiades in this issue.


Asunto(s)
Microondas , Neoplasias de la Tiroides , Humanos , Femenino , Adulto , Persona de Mediana Edad , Microondas/uso terapéutico , Estudios Retrospectivos , Cáncer Papilar Tiroideo/diagnóstico por imagen , Cáncer Papilar Tiroideo/cirugía , Hospitalización , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/cirugía
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