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1.
Cell ; 173(6): 1508-1519.e18, 2018 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-29754816

RESUMEN

As predicted by the notion that sister chromatid cohesion is mediated by entrapment of sister DNAs inside cohesin rings, there is perfect correlation between co-entrapment of circular minichromosomes and sister chromatid cohesion. In most cells where cohesin loads without conferring cohesion, it does so by entrapment of individual DNAs. However, cohesin with a hinge domain whose positively charged lumen is neutralized loads and moves along chromatin despite failing to entrap DNAs. Thus, cohesin engages chromatin in non-topological, as well as topological, manners. Since hinge mutations, but not Smc-kleisin fusions, abolish entrapment, DNAs may enter cohesin rings through hinge opening. Mutation of three highly conserved lysine residues inside the Smc1 moiety of Smc1/3 hinges abolishes all loading without affecting cohesin's recruitment to CEN loading sites or its ability to hydrolyze ATP. We suggest that loading and translocation are mediated by conformational changes in cohesin's hinge driven by cycles of ATP hydrolysis.


Asunto(s)
Proteínas de Ciclo Celular/química , Cromátides/química , Proteínas Cromosómicas no Histona/química , ADN/química , Adenosina Trifosfato/química , Animales , Sitios de Unión , Cromatina/química , Humanos , Hidrólisis , Lisina/química , Ratones , Mutación , Proteínas Nucleares/genética , Conformación Proteica , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Cohesinas
2.
Nature ; 610(7930): 173-181, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36171288

RESUMEN

Combination therapy with PD-1 blockade and IL-2 is highly effective during chronic lymphocytic choriomeningitis virus infection1. Here we examine the underlying basis for this synergy. We show that PD-1 + IL-2 combination therapy, in contrast to PD-1 monotherapy, substantially changes the differentiation program of the PD-1+TCF1+ stem-like CD8+ T cells and results in the generation of transcriptionally and epigenetically distinct effector CD8+ T cells that resemble highly functional effector CD8+ T cells seen after an acute viral infection. The generation of these qualitatively superior CD8+ T cells that mediate viral control underlies the synergy between PD-1 and IL-2. Our results show that the PD-1+TCF1+ stem-like CD8+ T cells, also referred to as precursors of exhausted CD8+ T cells, are not fate-locked into the exhaustion program and their differentiation trajectory can be changed by IL-2 signals. These virus-specific effector CD8+ T cells emerging from the stem-like CD8+ T cells after combination therapy expressed increased levels of the high-affinity IL-2 trimeric (CD25-CD122-CD132) receptor. This was not seen after PD-1 blockade alone. Finally, we show that CD25 engagement with IL-2 has an important role in the observed synergy between IL-2 cytokine and PD-1 blockade. Either blocking CD25 with an antibody or using a mutated version of IL-2 that does not bind to CD25 but still binds to CD122 and CD132 almost completely abrogated the synergistic effects observed after PD-1 + IL-2 combination therapy. There is considerable interest in PD-1 + IL-2 combination therapy for patients with cancer2,3, and our fundamental studies defining the underlying mechanisms of how IL-2 synergizes with PD-1 blockade should inform these human translational studies.


Asunto(s)
Linfocitos T CD8-positivos , Interleucina-2 , Receptor de Muerte Celular Programada 1 , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular/efectos de los fármacos , Quimioterapia Combinada , Humanos , Subunidad gamma Común de Receptores de Interleucina , Interleucina-2/inmunología , Interleucina-2/farmacología , Interleucina-2/uso terapéutico , Subunidad alfa del Receptor de Interleucina-2 , Subunidad beta del Receptor de Interleucina-2 , Coriomeningitis Linfocítica/tratamiento farmacológico , Coriomeningitis Linfocítica/inmunología , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Factor 1 de Transcripción de Linfocitos T
3.
Plant Cell ; 36(6): 2253-2271, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38416876

RESUMEN

Brassinosteroids (BRs) are widely used as plant growth regulators in modern agriculture. Understanding how BRs regulate nutrient signaling is crucial for reducing fertilizer usage. Here we elucidate that the central BR signaling inhibitor GSK3/SHAGGY-LIKE KINASE2 (GSK2) interacts directly with and phosphorylates PHOSPHATE STARVATION RESPONSE2 (OsPHR2), the key regulator of phosphate (Pi) signaling, to suppress its transcription factor activity in rice (Oryza sativa). We identify a critical phosphorylation site at serine residue S269 of OsPHR2 and demonstrate that phosphorylation by GSK2 or phosphor-mimic mutation of S269 substantially impairs the DNA-binding activity of OsPHR2, and thus diminishes expression of OsPHR2-induced genes and reduces Pi levels. Like BRs, Pi starvation noticeably induces GSK2 instability. We further show that this site-specific phosphorylation event is conserved in Arabidopsis (Arabidopsis thaliana), but varies among the PHR-family members, being present only in most land plants. These results unveil a distinctive post-transcriptional regulatory mechanism in Pi signaling by which BRs promote Pi acquisition, with a potential contribution to the environmental adaptability of plants during their evolution.


Asunto(s)
Brasinoesteroides , Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Arabidopsis/metabolismo , Arabidopsis/genética , Brasinoesteroides/metabolismo , ADN de Plantas/metabolismo , ADN de Plantas/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Oryza/metabolismo , Oryza/genética , Fosfatos/metabolismo , Fosforilación , Proteínas de Plantas/efectos de los fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transducción de Señal , Reguladores del Crecimiento de las Plantas/farmacología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
4.
Cell ; 150(5): 961-74, 2012 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-22901742

RESUMEN

Sister chromatid cohesion is mediated by entrapment of sister DNAs by a tripartite ring composed of cohesin's Smc1, Smc3, and α-kleisin subunits. Cohesion requires acetylation of Smc3 by Eco1, whose role is to counteract an inhibitory (antiestablishment) activity associated with cohesin's Wapl subunit. We show that mutations abrogating antiestablishment activity also reduce turnover of cohesin on pericentric chromatin. Our results reveal a "releasing" activity inherent to cohesin complexes transiently associated with Wapl that catalyzes their dissociation from chromosomes. Fusion of Smc3's nucleotide binding domain to α-kleisin's N-terminal domain also reduces cohesin turnover within pericentric chromatin and permits establishment of Wapl-resistant cohesion in the absence of Eco1. We suggest that releasing activity opens the Smc3/α-kleisin interface, creating a DNA exit gate distinct from its proposed entry gate at the Smc1/3 interface. According to this notion, the function of Smc3 acetylation is to block its dissociation from α-kleisin. The functional implications of regulated ring opening are discussed.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Acetilación , Acetiltransferasas/metabolismo , Cromosomas Fúngicos/metabolismo , Replicación del ADN , Proteínas Nucleares/metabolismo , Saccharomyces cerevisiae/citología , Cohesinas
5.
Nature ; 590(7847): 600-605, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33408412

RESUMEN

The intensive application of inorganic nitrogen underlies marked increases in crop production, but imposes detrimental effects on ecosystems1,2: it is therefore crucial for future sustainable agriculture to improve the nitrogen-use efficiency of crop plants. Here we report the genetic basis of nitrogen-use efficiency associated with adaptation to local soils in rice (Oryza sativa L.). Using a panel of diverse rice germplasm collected from different ecogeographical regions, we performed a genome-wide association study on the tillering response to nitrogen-the trait that is most closely correlated with nitrogen-use efficiency in rice-and identified OsTCP19 as a modulator of this tillering response through its transcriptional response to nitrogen and its targeting to the tiller-promoting gene DWARF AND LOW-TILLERING (DLT)3,4. A 29-bp insertion and/or deletion in the OsTCP19 promoter confers a differential transcriptional response and variation in the tillering response to nitrogen among rice varieties. The allele of OsTCP19 associated with a high tillering response to nitrogen is prevalent in wild rice populations, but has largely been lost in modern cultivars: this loss correlates with increased local soil nitrogen content, which suggests that it might have contributed to geographical adaptation in rice. Introgression of the allele associated with a high tillering response into modern rice cultivars boosts grain yield and nitrogen-use efficiency under low or moderate levels of nitrogen, which demonstrates substantial potential for rice breeding and the amelioration of negative environment effects by reducing the application of nitrogen to crops.


Asunto(s)
Adaptación Fisiológica/genética , Productos Agrícolas/genética , Nitrógeno/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Suelo/química , Alelos , Productos Agrícolas/metabolismo , Epistasis Genética , Regulación de la Expresión Génica de las Plantas , Introgresión Genética , Variación Genética , Estudio de Asociación del Genoma Completo , Mutación INDEL , Oryza/crecimiento & desarrollo , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas/genética
6.
Nature ; 599(7884): 222-228, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34587621

RESUMEN

The transition metal kagome lattice materials host frustrated, correlated and topological quantum states of matter1-9. Recently, a new family of vanadium-based kagome metals, AV3Sb5 (A = K, Rb or Cs), with topological band structures has been discovered10,11. These layered compounds are nonmagnetic and undergo charge density wave transitions before developing superconductivity at low temperatures11-19. Here we report the observation of unconventional superconductivity and a pair density wave (PDW) in CsV3Sb5 using scanning tunnelling microscope/spectroscopy and Josephson scanning tunnelling spectroscopy. We find that CsV3Sb5 exhibits a V-shaped pairing gap Δ ~ 0.5 meV and is a strong-coupling superconductor (2Δ/kBTc ~ 5) that coexists with 4a0 unidirectional and 2a0 × 2a0 charge order. Remarkably, we discover a 3Q PDW accompanied by bidirectional 4a0/3 spatial modulations of the superconducting gap, coherence peak and gap depth in the tunnelling conductance. We term this novel quantum state a roton PDW associated with an underlying vortex-antivortex lattice that can account for the observed conductance modulations. Probing the electronic states in the vortex halo in an applied magnetic field, in strong field that suppresses superconductivity and in zero field above Tc, reveals that the PDW is a primary state responsible for an emergent pseudogap and intertwined electronic order. Our findings show striking analogies and distinctions to the phenomenology of high-Tc cuprate superconductors, and provide groundwork for understanding the microscopic origin of correlated electronic states and superconductivity in vanadium-based kagome metals.

7.
Mol Cell ; 70(6): 1134-1148.e7, 2018 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-29932904

RESUMEN

Cohesin organizes DNA into chromatids, regulates enhancer-promoter interactions, and confers sister chromatid cohesion. Its association with chromosomes is regulated by hook-shaped HEAT repeat proteins that bind Scc1, namely Scc3, Pds5, and Scc2. Unlike Pds5, Scc2 is not a stable cohesin constituent but, as shown here, transiently replaces Pds5. Scc1 mutations that compromise its interaction with Scc2 adversely affect cohesin's ATPase activity and loading. Moreover, Scc2 mutations that alter how the ATPase responds to DNA abolish loading despite cohesin's initial association with loading sites. Lastly, Scc2 mutations that permit loading in the absence of Scc4 increase Scc2's association with chromosomal cohesin and reduce that of Pds5. We suggest that cohesin switches between two states: one with Pds5 bound that is unable to hydrolyze ATP efficiently but is capable of release from chromosomes and another in which Scc2 replaces Pds5 and stimulates ATP hydrolysis necessary for loading and translocation from loading sites.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Adenosina Trifosfatasas/genética , Proteínas de Ciclo Celular/genética , Cromátides/genética , Cromátides/metabolismo , Proteínas Cromosómicas no Histona/genética , Segregación Cromosómica , ADN de Hongos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Cohesinas
8.
J Biol Chem ; 300(1): 105593, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38145746

RESUMEN

Neural precursor cell expressed developmentally downregulated 4 (NEDD4), an E3 ubiquitin ligase, is commonly upregulated in human hepatocellular carcinoma (HCC) and functions as an oncogenic factor in the progression of HCC, but the molecular mechanism needs be further explored. In this study, we found that NEDD4 could facilitate the proliferation of HCC cells, which was associated with regulating the ERK signaling. Further investigation showed that protocadherin 17 (PCDH17) was a potential substrate of NEDD4, and restoration of PCDH17 could block the facilitation of ERK signaling and HCC cells proliferation induced by NEDD4 overexpression. Whereafter, we confirmed that NEDD4 interacted with PCDH17 and promoted the Lys33-linked polyubiquitination and degradation of it via the proteasome pathway. Finally, NEDD4 protein level was found to be inversely correlated with that of PCDH17 in human HCC tissues. In conclusion, these results suggest that NEDD4 acts as an E3 ubiquitin ligase for PCDH17 ubiquitination and degradation thereby promoting the proliferation of HCC cells through regulating the ERK signaling, which may provide novel evidence for NEDD4 to be a promising therapeutic target for HCC.


Asunto(s)
Cadherinas , Carcinoma Hepatocelular , Neoplasias Hepáticas , Ubiquitina-Proteína Ligasas Nedd4 , Humanos , Carcinoma Hepatocelular/patología , Proliferación Celular , Neoplasias Hepáticas/patología , Ubiquitina-Proteína Ligasas Nedd4/genética , Ubiquitina-Proteína Ligasas Nedd4/metabolismo , Ubiquitinación , Cadherinas/metabolismo
9.
J Med Genet ; 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38802138

RESUMEN

BACKGROUND: Balanced insertional translocations (BITs) can increase the risk of infertility, recurrent miscarriages or neonatal birth defects due to chromosomal imbalances in gametes. However, studies on preimplantation genetic testing (PGT) for patients carrying BITs are inadequate. METHODS: A preimplantation genetic genotyping and haplotype analysis approach was developed and implemented in this study. Genome-wide SNP genotyping was performed, followed by core family-based haplotype analysis. The balanced insertion segments in euploid embryos were inferred from the haplotypes inherited from the carrier parent. RESULTS: A total of 10 BIT carrier couples were enrolled in our study. 15 in vitro fertilisation cycles were conducted, resulting in 73 blastocysts biopsied and subjected to PGT analysis. Among these, 20 blastocysts displayed rearrangement-related imbalances, 13 exhibited de novo aneuploidies, 15 presented a complex anomaly involving both imbalances and additional aneuploidies, while 25 were euploid. Within the euploid embryos, 12 were balanced carrier embryos and 13 were non-carrier embryos. To date, eight non-carrier and one carrier embryos have been transferred, resulting in seven clinical pregnancies. All pregnancies were recommended to perform prenatal diagnosis, our date revealed complete concordance between fetal genetic testing results and PGT results. Presently, five infants have been born from these pregnancies, and two pregnancies are still ongoing. CONCLUSION: The proposed method facilitates comprehensive chromosome screening and the concurrent identification of balanced insertions or normal karyotypes in embryos. This study offers an effective and universally applicable strategy for BIT carriers to achieve a healthy pregnancy and prevent the transmission of BITs to their offspring.

10.
Nucleic Acids Res ; 51(10): 4774-4790, 2023 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-36929421

RESUMEN

Normal erythropoiesis requires the precise regulation of gene expression patterns, and transcription cofactors play a vital role in this process. Deregulation of cofactors has emerged as a key mechanism contributing to erythroid disorders. Through gene expression profiling, we found HES6 as an abundant cofactor expressed at gene level during human erythropoiesis. HES6 physically interacted with GATA1 and influenced the interaction of GATA1 with FOG1. Knockdown of HES6 impaired human erythropoiesis by decreasing GATA1 expression. Chromatin immunoprecipitation and RNA sequencing revealed a rich set of HES6- and GATA1-co-regulated genes involved in erythroid-related pathways. We also discovered a positive feedback loop composed of HES6, GATA1 and STAT1 in the regulation of erythropoiesis. Notably, erythropoietin (EPO) stimulation led to up-regulation of these loop components. Increased expression levels of loop components were observed in CD34+ cells of polycythemia vera patients. Interference by either HES6 knockdown or inhibition of STAT1 activity suppressed proliferation of erythroid cells with the JAK2V617F mutation. We further explored the impact of HES6 on polycythemia vera phenotypes in mice. The identification of the HES6-GATA1 regulatory loop and its regulation by EPO provides novel insights into human erythropoiesis regulated by EPO/EPOR and a potential therapeutic target for the management of polycythemia vera.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Eritropoyesis , Factor de Transcripción GATA1 , Proteínas Represoras , Animales , Humanos , Ratones , Secuencia de Bases , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Células Eritroides/metabolismo , Factor de Transcripción GATA1/metabolismo , Perfilación de la Expresión Génica , Policitemia Vera/genética , Policitemia Vera/metabolismo , Proteínas Represoras/metabolismo
11.
Proc Natl Acad Sci U S A ; 119(49): e2208904119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36445966

RESUMEN

The protooncoprotein N-Myc, which is overexpressed in approximately 25% of neuroblastomas as the consequence of MYCN gene amplification, has long been postulated to regulate DNA double-strand break (DSB) repair in neuroblastoma cells, but experimental evidence of this function is presently scant. Here, we show that N-Myc transcriptionally activates the long noncoding RNA MILIP to promote nonhomologous end-joining (NHEJ) DNA repair through facilitating Ku70-Ku80 heterodimerization in neuroblastoma cells. High MILIP expression was associated with poor outcome and appeared as an independent prognostic factor in neuroblastoma patients. Knockdown of MILIP reduced neuroblastoma cell viability through the induction of apoptosis and inhibition of proliferation, retarded neuroblastoma xenograft growth, and sensitized neuroblastoma cells to DNA-damaging therapeutics. The effect of MILIP knockdown was associated with the accumulation of DNA DSBs in neuroblastoma cells largely due to decreased activity of the NHEJ DNA repair pathway. Mechanistical investigations revealed that binding of MILIP to Ku70 and Ku80 increased their heterodimerization, and this was required for MILIP-mediated promotion of NHEJ DNA repair. Disrupting the interaction between MILIP and Ku70 or Ku80 increased DNA DSBs and reduced cell viability with therapeutic potential revealed where targeting MILIP using Gapmers cooperated with the DNA-damaging drug cisplatin to inhibit neuroblastoma growth in vivo. Collectively, our findings identify MILIP as an N-Myc downstream effector critical for activation of the NHEJ DNA repair pathway in neuroblastoma cells, with practical implications of MILIP targeting, alone and in combination with DNA-damaging therapeutics, for neuroblastoma treatment.


Asunto(s)
Roturas del ADN de Doble Cadena , Reparación del ADN por Unión de Extremidades , Neuroblastoma , ARN Largo no Codificante , Humanos , ADN/genética , Reparación del ADN por Unión de Extremidades/genética , Reparación del ADN/genética , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/genética , ARN Largo no Codificante/genética
12.
Traffic ; 23(11): 526-537, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36109347

RESUMEN

The prevalence of a high-energy diet and a sedentary lifestyle has increased the incidence of type 2 diabetes (T2D). T2D is a chronic disease characterized by high blood glucose levels and insulin resistance in peripheral tissues. The pathological mechanism of this disease is not fully clear. Accumulated evidence has shown that noncoding RNAs have an essential regulatory role in the progression of diabetes and its complications. The roles of small noncoding RNAs, such as miRNAs, in T2D, have been extensively investigated, while the function of long noncoding RNAs (lncRNAs) in T2D has been unstudied. It has been reported that lncRNAs in T2D play roles in the regulation of pancreatic function, peripheral glucose homeostasis and vascular inflammation. In addition, lncRNAs carried by small extracellular vesicles (sEV) were shown to mediate communication between organs and participate in diabetes progression. Some sEV lncRNAs derived from stem cells are being developed as potential therapeutic agents for diabetic complications. In this review, we summarize the current knowledge relating to lncRNA biogenesis, the mechanisms of lncRNA sorting into sEV and the regulatory roles of lncRNAs and sEV lncRNAs in diabetes. Knowledge of lncRNAs and sEV lncRNAs in diabetes will aid in the development of new therapeutic drugs for T2D in the future.


Asunto(s)
Diabetes Mellitus Tipo 2 , Vesículas Extracelulares , MicroARNs , ARN Largo no Codificante , ARN Pequeño no Traducido , Glucemia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patología , Humanos , ARN Largo no Codificante/genética
13.
J Neurosci ; 43(4): 559-570, 2023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36639904

RESUMEN

Thalamus is a critical component of the limbic system that is extensively involved in both basic and high-order brain functions. However, how the thalamic structure and function develops at macroscopic and microscopic scales during the perinatal period development is not yet well characterized. Here, we used multishell high-angular resolution diffusion MRI of 144 preterm-born and full-term infants in both sexes scanned at 32-44 postmenstrual weeks (PMWs) from the Developing Human Connectome Project database to investigate the thalamic development in morphology, microstructure, associated connectivity, and subnucleus division. We found evident anatomic expansion and linear increases of fiber integrity in the lateral side of thalamus compared with the medial part. The tractography results indicated that thalamic connection to the frontal cortex developed later than the other thalamocortical connections (parieto-occipital, motor, somatosensory, and temporal). Using a connectivity-based segmentation strategy, we revealed that functional partitions of thalamic subdivisions were formed at 32 PMWs or earlier, and the partition developed toward the adult pattern in a lateral-to-medial pattern. Collectively, these findings revealed faster development of the lateral thalamus than the central part as well as a posterior-to-anterior developmental gradient of thalamocortical connectivity from the third trimester to early infancy.SIGNIFICANCE STATEMENT This is the first study that characterizes the spatiotemporal developmental pattern of thalamus during the third trimester to early infancy. We found that thalamus develops in a lateral-to-medial pattern for both thalamic microstructures and subdivisions; and thalamocortical connectivity develops in a posterior-to-anterior gradient that thalamofrontal connectivity appears later than the other thalamocortical connections. These findings may enrich our understanding of the developmental principles of thalamus and provide references for the atypical brain growth in neurodevelopmental disorders.


Asunto(s)
Conectoma , Imagen por Resonancia Magnética , Masculino , Adulto , Recién Nacido , Femenino , Embarazo , Humanos , Lactante , Tercer Trimestre del Embarazo , Imagen de Difusión por Resonancia Magnética , Conectoma/métodos , Tálamo , Vías Nerviosas/diagnóstico por imagen , Corteza Cerebral
14.
Neuroimage ; 295: 120660, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38815676

RESUMEN

The topological organization of the macroscopic cortical networks important for the development of complex brain functions. However, how the cortical morphometric organization develops during the third trimester and whether it demonstrates sexual and individual differences at this particular stage remain unclear. Here, we constructed the morphometric similarity network (MSN) based on morphological and microstructural features derived from multimodal MRI of two independent cohorts (cross-sectional and longitudinal) scanned at 30-44 postmenstrual weeks (PMW). Sex difference and inter-individual variations of the MSN were also examined on these cohorts. The cross-sectional analysis revealed that both network integration and segregation changed in a nonlinear biphasic trajectory, which was supported by the results obtained from longitudinal analysis. The community structure showed remarkable consistency between bilateral hemispheres and maintained stability across PMWs. Connectivity within the primary cortex strengthened faster than that within high-order communities. Compared to females, male neonates showed a significant reduction in the participation coefficient within prefrontal and parietal cortices, while their overall network organization and community architecture remained comparable. Furthermore, by using the morphometric similarity as features, we achieved over 65 % accuracy in identifying an individual at term-equivalent age from images acquired after birth, and vice versa. These findings provide comprehensive insights into the development of morphometric similarity throughout the perinatal cortex, enhancing our understanding of the establishment of neuroanatomical organization during early life.


Asunto(s)
Corteza Cerebral , Imagen por Resonancia Magnética , Caracteres Sexuales , Humanos , Femenino , Masculino , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/crecimiento & desarrollo , Corteza Cerebral/anatomía & histología , Recién Nacido , Estudios Transversales , Estudios Longitudinales , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/crecimiento & desarrollo , Red Nerviosa/anatomía & histología , Embarazo
15.
Cancer ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38781433

RESUMEN

BACKGROUND: Effective systemic therapy remains limited for advanced esophageal squamous cell carcinoma (ESCC) and hepatocellular carcinoma (HCC), particularly after prior failed treatment with immune checkpoint inhibitors (ICIs). Theoretically, a combination of tyrosine kinase inhibitors (TKIs) with ICIs may restore immunotherapy sensitivity. METHODS: In this phase 1b study, patients received AL2846, an antiangiogenic TKI with multiple targets (c-MET, VEGFR1, c-KIT, Axl, RET, KDR, and VEGFR3), in combination with an anti-PD-L1 antibody (TQB2450) until disease progression, intolerable toxicity, death, or discontinuation for any cause. The primary end points included overall response rate (ORR) and safety, with secondary end points encompassing progression-free survival (PFS), overall survival (OS), disease control rate (DCR), and duration of response. RESULTS: Between November 2021 and September 2022, 18 patients with ESCC and 15 patients with HCC, whose ORR was 11.1% (95% confidence interval [CI], 3.1%-32.8%) and 0%, respectively, were enrolled. Adverse events (AEs) of any grade and treatment-related AEs were documented in 32 patients (97.0%) and 31 patients (93.9%), respectively. Grade 3 or higher AEs were observed in 10 patients (30.3%), with vomiting (6.1%) and infectious pneumonia (9.1%) being the most prevalent. Median PFS and OS values were 3.22 months (95% CI, 1.35-5.68 months) and 5.98 months (95% CI, 3.71-8.87 months), respectively, in patients with ESCC, and 5.55 months (95% CI, 2.66 months to not evaluable [NE]) and 16.72 months (95% CI, 4.86 months to NE), respectively, in patients with HCC. The DCRs were 66.7% (95% CI, 43.75%-83.72%) in patients with ESCC and 73.3% (95% CI, 48.05%-89.10%) in patients with HCC. CONCLUSIONS: Combined TQB2450 and AL2846 therapy exhibited a favorable safety profile in immunotherapy-refractory patients with advanced ESCC and HCC.

16.
Anal Chem ; 96(16): 6329-6336, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38597405

RESUMEN

The simultaneous discrimination of multiple homologous sequences faces challenges due to the high similarity of sequences and the complexity of the discrimination system in most reported works. Herein, a simple and ingenious analysis method was developed to identify eight miRNAs of the let-7 family by combining logic gates and entropy-driven catalytic (EDC)-based lanthanide labeling inductively coupled plasma mass spectrometry (ICP-MS) technology. Specifically, eight miRNAs were first divided into four types according to the difference of bases in the domains 2 and 3 on sequences. To identify the type of targets, a DNA logic gate was constructed with two strand displacement reactions on magnetic beads that could be initiated by different types of targets. Based on the difference of the output signals after two strand displacement reactions, the type of targets was distinguished preliminarily. Then, the discrimination of a specific target was achieved with EDC-based lanthanide labeling ICP-MS detection. By labeling the different magnetic probes with different elemental tags, a specific element signal released from magnetic beads after EDC could be detected by ICP-MS, and therefore, simultaneous detection of homologous sequences was completed. This work provided a novel and simple method for highly specific identification of homologous sequences with the assistance of a logic gate and can promote further development of elemental labeling ICP-MS in the field of multiple analysis.

17.
Anal Chem ; 96(2): 766-774, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38158582

RESUMEN

Microfluidic chips have emerged as a promising tool for sorting and enriching circulating tumor cells (CTCs) in blood, while the efficacy and purity of CTC sorting greatly depend on chip design. Herein, a novel cascaded phase-transfer microfluidic chip was developed for high-efficiency sorting, purification, release, and detection of MCF-7 cells (as a model CTC) in blood samples. MCF-7 cells were specifically captured by EpCAM aptamer-modified magnetic beads and then introduced into the designed cascaded phase-transfer microfluidic chip that consisted of three functional regions (sorting, purification, and release zone). In the sorting zone, the MCF-7 cells moved toward the inner wall of the channel and entered the purification zone for primary separation from white blood cells; in the purification zone, the MCF-7 cells were transferred to the phosphate-buffered saline flow under the interaction of Dean forces and central magnetic force, achieving high purification of MCF-7 cells from blood samples; in the release zone, MCF-7 cells were further transferred into the nuclease solution and fixed in groove by the strong magnetic force and hydrodynamic force, and the continuously flowing nuclease solution cleaved the aptamer on the trapped MCF-7 cells, causing gentle release of MCF-7 cells for subsequent inductively coupled plasma mass spectrometry (ICP-MS) detection or further cultivation. By measurement of the endogenous element Zn in the cells using ICP-MS for cell counting, an average cell recovery of 84% for MCF-7 cells was obtained in spiked blood samples. The developed method was applied in the analysis of real blood samples from healthy people and breast cancer patients, and CTCs were successfully detected in all tested patient samples (16/16). Additionally, the removal of the magnetic probes on the cell surface significantly improved cell viability up to 99.3%. Therefore, the developed cascaded phase-transfer microfluidic chip ICP-MS system possessed high integration for CTCs analysis with high cell viability, cell recovery, and purity, showing great advantages in early clinical cancer diagnosis.


Asunto(s)
Técnicas Analíticas Microfluídicas , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patología , Microfluídica , Separación Celular/métodos , Línea Celular Tumoral , Técnicas Analíticas Microfluídicas/métodos , Fenómenos Magnéticos
18.
Anal Chem ; 96(23): 9325-9331, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38758929

RESUMEN

Various hazardous volatile organic compounds (VOCs) are frequently released into environments during accidental events that cause many hazards to ecosystems and humans. Therefore, rapid, sensitive, and on-site detection of hazardous VOCs is crucial to understand their compositions, characteristics, and distributions in complex environments. However, manual handling of hazardous VOCs remains a challenging task, because of the inaccessible environments and health risk. In this work, we designed a quadruped robotic sampler to reach different complex environments for capturing trace hazardous VOCs using a needle trap device (NTD) by remote manipulation. The captured samples were rapidly identified by portable mass spectrometry (MS) within minutes. Rapid detection of various hazardous VOCs including toxicants, chemical warfare agents, and burning materials from different environments was successfully achieved using this robot-MS system. On-site detection of 83 typical hazardous VOCs was examined. Acceptable analytical performances including low detection limits (at subng/mL level), good reproducibility (relative standard deviation (RSD) < 20%, n = 6), excellent quantitative ability (R2 > 0.99), and detection speed (within minutes) were also obtained. Our results show that the robot-MS system has excellent performance including safety, controllability, applicability, and robustness under dangerous chemical conditions.


Asunto(s)
Espectrometría de Masas , Robótica , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/análisis , Espectrometría de Masas/métodos , Sustancias Peligrosas/análisis , Sustancias Peligrosas/aislamiento & purificación , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/instrumentación , Límite de Detección
19.
Small ; : e2402748, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898734

RESUMEN

Defect engineering is considered as a flexible and effective mean to improve the performance of Fenton-like reactions. Herein, a simple method is employed to synthesize Co3O4 catalysts with Co-O vacancy pairs (VP) for peroxymonosulfate (PMS) activation. Multi-scaled characterization, experimental, and simulation results jointly revealed that the cation vacancies-VCo contributed to enhanced conductivity and anion vacancies-VO provided a new active center for the 1O2 generation. Co3O4-VP can optimize the O 2p and Co 3d bands with the strong assistance of synergistic double vacancies to reduce the reaction energy barrier of the "PMS → Co(IV) = O → 1O2" pathway, ultimately triggering the stable transition of mechanism. Co3O4-VP catalysts with radical-nonradical collaborative mechanism achieve the synchronous improvement of activity and stability, and have good environmental robustness to favor water decontamination applications. This result highlights the possibility of utilizing anion and cation vacancy engineering strategies to rational design Co3O4-based materials widely used in catalytic reactions.

20.
Small ; : e2404066, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837665

RESUMEN

Inverted organic solar cells (OSCs) have garnered significant interest due to their remarkable stability. In this study, the efficiency and stability of inverted OSCs are enhanced via the in situ self-organization (SO) of an interfacial modification material Phen-NaDPO onto tin oxide (SnO2). During the device fabrication, Phen-NaDPO is spin-coated with the active materials all together on SnO2. Driven by the interactions with SnO2 and the thermodynamic forces due to its high surface energy and the convection flow, Phen-NaDPO spontaneously migrates to the SnO2 interface, resulting in the formation of an in situ modification layer on SnO2. This self-organization of Phen-NaDPO not only effectively reduces the work function of SnO2, but also enhances the ordered molecular stacking and manipulates the vertical morphology of the active layer, which suppress the surface trap-assisted recombination and minimize the charge extraction. As a result, the SO devices based on PM6:Y6 exhibit significantly improved photovoltaic performance with an enhanced power conversion efficiency of 17.62%. Moreover, the stability of the SO device is also improved. Furthermore, the SO ternary devices based on PM6:D18:L8-BO achieved an impressive PCE of 18.87%, standing as one of the highest values for single-junction inverted organic solar cells to date.

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