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Background: AIDS-related NK/T-cell lymphoma is a rare subtype of AIDS-related lymphomas, characterized by a poor prognosis and lack of standardized treatment protocols. To date, there have been no reported cases of AIDS-associated NK/T-cell lymphoma in remission followed by treatment-related acute myeloid leukemia (t-AML), where both the lymphoma and AML achieved remission and long-term survival through chemotherapy alone. Case presentation: We report a case of a patient diagnosed with AIDS-related extra-nodal NK/T-cell lymphoma (ENKTCL). The patient achieved complete remission after receiving six cycles of chemotherapy, local radiotherapy, and combination antiretroviral therapy (cART). Throughout the follow-up period, the patient continued cART treatment, maintaining an HIV-RNA level below the lower limit of detection. However, 70 months later, the patient developed new symptoms and was subsequently diagnosed with acute myeloid leukemia (AML) M4 subtype. Following the completion of 10 cycles of chemotherapy and ongoing cART, the patient achieved complete remission of AML, with an overall survival time exceeding 103 months from the initial ENKTCL diagnosis. Conclusions: This case highlights the effectiveness of chemotherapy combined with cART in the treatment of AIDS-associated NK/T-cell lymphoma and secondary treatment-related leukemia. This approach may serve as a viable option for patients who are not candidates for bone marrow transplantation. Furthermore, this case underscores the importance of long-term follow-up in the management of AIDS-associated malignancies.
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BACKGROUND: CD83 are closely related to the pathogenesis of immune thrombocytopenia (ITP), but the exact mechanism remains unclear. AIM: To explore the relationship between CD83 and CD4+ T cell subsets and clarify the role of CD83 in the pathogenesis of ITP. METHODS: RT-qPCR and Flow cytometry were used to illustrate CD83 expression. The downregulation and overexpression of DC-CD83 were co-cultured with CD4+ T cells to detect cell proliferation, co-cultured supernatant cytokines and Tregs expression. RESULTS: The results indicate that the ITP patients showed higher expression of CD83 than the healthy controls. The proliferation of CD4+ T cells was inhibited by downregulation of DCs-CD83 but promoted by overexpression of DCs-CD83. siRNA-CD83 inhibited proinflammatory IFN-γ and IL-17 secretion while raising TGF-ß, IL-10 concentrations. Overexpression of DCs-CD83 promoted Tregs expression. CONCLUSION: The Th1/Th2 and Th17/Tregs polarization were reversed via interfering DCs with siRNA-CD83. CD83 plays an important role in ITP pathogenesis, suggesting novel treatment for ITP patients.
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Antígenos CD , Antígeno CD83 , Inmunoglobulinas , Glicoproteínas de Membrana , Púrpura Trombocitopénica Idiopática , Humanos , Púrpura Trombocitopénica Idiopática/inmunología , Púrpura Trombocitopénica Idiopática/patología , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Antígenos CD/metabolismo , Inmunoglobulinas/genética , Inmunoglobulinas/metabolismo , Femenino , Masculino , Adulto , Persona de Mediana Edad , Citocinas/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismoRESUMEN
In order to assess homeostatic mechanisms in the lung after COVID-19, changes in the protein signature of bronchoalveolar lavage from 45 patients with mild to moderate disease at three phases (acute, recovery, and convalescent) are evaluated over a year. During the acute phase, inflamed and uninflamed phenotypes are characterized by the expression of tissue repair and host defense response molecules. With recovery, inflammatory and fibrogenic mediators decline and clinical symptoms abate. However, at 9 months, quantified radiographic abnormalities resolve in the majority of patients, and yet compared to healthy persons, all showed ongoing activation of cellular repair processes and depression of the renin-kallikrein-kinin, coagulation, and complement systems. This dissociation of prolonged reparative processes from symptom and radiographic resolution suggests that occult ongoing disruption of the lung proteome is underrecognized and may be relevant to recovery from other serious viral pneumonias.
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COVID-19 , Pulmón , Proteoma , SARS-CoV-2 , Humanos , COVID-19/metabolismo , COVID-19/patología , COVID-19/virología , Proteoma/metabolismo , Pulmón/metabolismo , Pulmón/patología , Pulmón/diagnóstico por imagen , Femenino , Masculino , Persona de Mediana Edad , SARS-CoV-2/aislamiento & purificación , Estudios Longitudinales , Adulto , Líquido del Lavado Bronquioalveolar/química , AncianoRESUMEN
GeSe, an analogue of SnSe, shows promise in exhibiting exceptional thermoelectric performance in the Pnma phase. The constraints on its dopability, however, pose challenges in attaining optimal carrier concentrations and improving ZT values. This study demonstrates a crystal structure evolution strategy for achieving highly doped samples and promising ZTs in GeSe via LiBiTe2 alloying. A rhombohedral phase (R3m) can be stabilized in the GeSe-LiBiTe2 system, further evolving into a cubic (Fm3Ì m) phase with a rising temperature. The band structures of GeSe-LiBiTe2 in the rhombohedral and cubic phases feature a similar multiple-valley energy-converged valence band of L and Σ bands. The observed high carrier concentration (â¼1020 cm-3) reflects the effective convergence of these bands, enabling a high density-of-states effective mass and an enhanced power factor. Moreover, a very low lattice thermal conductivity of 0.6-0.5 W m-1 K-1 from 300 to 723 K is achieved in 0.9GeSe-0.1LiBiTe2, approaching the amorphous limit value. This remarkably low lattice thermal conductivity is related to phonon scattering from point defects, planar vacancies, and ferroelectric instability-induced low-energy Einstein oscillators. Finally, a maximum ZT value of 1.1 to 1.3 at 723 K is obtained, with a high average ZT value of over 0.8 (400-723 K) in 0.9GeSe-0.1LiBiTe2 samples. This study establishes a viable route for tailoring crystal structures to significantly improve the performance of GeSe-related compounds.
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Bioinspired molecular engineering strategies have emerged as powerful tools that significantly enhance the development of novel therapeutics, improving efficacy, specificity, and safety in disease treatment. Recent advancements have focused on identifying and utilizing disease-associated biomarkers to optimize drug activity and address challenges inherent in traditional therapeutics, such as frequent drug administrations, poor patient adherence, and increased risk of adverse effects. In this review, we provide a comprehensive overview of the latest developments in bioinspired artificial systems (BAS) that use molecular engineering to tailor therapeutic responses to drugs in the presence of disease-specific biomarkers. We examine the transition from open-loop systems, which rely on external cues, to closed-loop feedback systems capable of autonomous self-regulation in response to disease-associated biomarkers. We detail various BAS modalities designed to achieve biomarker-driven therapy, including activatable prodrug molecules, smart drug delivery platforms, autonomous artificial cells, and synthetic receptor-based cell therapies, elucidating their operational principles and practical inâ vivo applications. Finally, we discuss the current challenges and future perspectives in the advancement of BAS-enabled technology and envision that ongoing advancements toward more programmable and customizable BAS-based therapeutics will significantly enhance precision medicine.
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Biomarcadores , Sistemas de Liberación de Medicamentos , Humanos , Sistemas de Liberación de Medicamentos/métodos , Profármacos/química , Profármacos/uso terapéutico , Medicina de Precisión/métodos , Células Artificiales/química , AnimalesRESUMEN
While epidermal growth factor (EGF) shows promise in addressing the clinical manifestations of intestinal ulcerative diseases by activating the EGF receptor (EGFR)-mediated cell signaling, its clinical application is hampered by poor protein hydrolytic stability, low thermostability, and difficulty in modification. The development of a novel EGFR agonist for ulcerative colitis remains an urgent need, necessitating innovative solutions to overcome the limitations of current therapies via recombinant EGF protein. Herein, we introduce a novel DNA agonist for EGFR, Dimer-YL, which employs a bivalent aptamer to induce stable receptor dimerization, thereby activating the EGFR signaling and related cell behaviors. Dimer-YL has been demonstrated to recapitulate the EGF-promoted cellular behaviors, including proliferation and migration, as well as repair the damage of intercellular tight junctions. Furthermore, our findings demonstrate the potent therapeutic function of Dimer-YL in alleviating DSS-induced ulcerative colitis in vivo. Together, the present work has revealed Dimer-YL as an innovative DNA molecule for effective EGFR activation, offering promise for the development of EGFR-agonistic agents for therapeutic purposes.
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Aptámeros de Nucleótidos , Colitis Ulcerosa , Receptores ErbB , Transducción de Señal , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/metabolismo , Receptores ErbB/metabolismo , Aptámeros de Nucleótidos/farmacología , Aptámeros de Nucleótidos/química , Animales , Transducción de Señal/efectos de los fármacos , Ratones , Humanos , Proliferación Celular/efectos de los fármacos , ADN/metabolismo , Ratones Endogámicos C57BL , Sulfato de Dextran , Movimiento Celular/efectos de los fármacosRESUMEN
Pectin, a natural polysaccharide, holds versatile applications in food and pharmaceuticals. However, there is a need for further exploration into extracting novel functional fractions and characterizing them thoroughly. In this study, a sequential extraction approach was used to obtain three distinct lemon pectin (LP) fractions from lemon peels (Citrus Eureka): LP extracted with sodium acetate (LP-SA), LP extracted with ethylenediaminetetraacetic acid (LP-EDTA), and LP extracted with sodium carbonate and sodium borohydride (LP-SS). Comprehensive analysis revealed low methyl-esterification in all fractions. LP-SA and LP-SS displayed characteristics of rhamnogalacturonan-I type pectin, while LP-EDTA mainly consisted of homogalacturonan pectin. Notably, LP-SA formed self-aggregated particles with rough surfaces, LP-EDTA showed interlocking linear structures with smooth planes, and LP-SS exhibited branch chain structures with smooth surfaces. Bioactivity analysis indicated that LP-SA had significant apparent viscosity and ABTS radical scavenging activity, while both LP-EDTA and LP-SS showed excellent thermal stability according to thermogravimetric analysis (TGA). Furthermore, LP-SS exhibited remarkable gel-forming ability and significant hydroxyl free radicals scavenging activity. In conclusion, this study presents a novel method for extracting various lemon pectin fractions with unique structural and bioactive properties, contributing insights for advanced applications in the food and pharmaceutical sectors.
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Antioxidantes , Citrus , Pectinas , Pectinas/química , Pectinas/aislamiento & purificación , Citrus/química , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/aislamiento & purificación , Fenómenos Químicos , Viscosidad , Frutas/química , Extractos Vegetales/química , Extractos Vegetales/farmacologíaRESUMEN
Synthetic signaling receptors enable programmable cellular responses coupling with customized inputs. However, engineering a designer force-sensing receptor to rewire mechanotransduction remains largely unexplored. Herein, we introduce nongenetically engineered artificial mechanoreceptors (AMRs) capable of reprogramming non-mechanoresponsive receptor tyrosine kinases (RTKs) to sense user-defined force cues, enabling de novo-designed mechanotransduction. AMR is a modular DNA-protein chimera comprising a mechanosensing-and-transmitting DNA nanodevice grafted on natural RTKs via aptameric anchors. AMR senses intercellular tensile force via an allosteric DNA mechano-switch with tunable piconewton-sensitive force tolerance, actuating a force-triggered dynamic DNA assembly to manipulate RTK dimerization and activate intracellular signaling. By swapping the force-reception ligands, we demonstrate the AMR-mediated activation of c-Met, a representative RTK, in response to the cellular tensile forces mediated by cell-adhesion proteins (integrin, E-cadherin) or membrane protein endocytosis (CI-M6PR). Moreover, AMR also allows the reprogramming of FGFR1, another RTK, to customize mechanobiological function, for example, adhesion-mediated neural stem cell maintenance.
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ADN , Mecanorreceptores , Mecanotransducción Celular , ADN/metabolismo , ADN/química , Mecanotransducción Celular/efectos de los fármacos , Humanos , Mecanorreceptores/metabolismo , Transducción de Señal/efectos de los fármacos , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Cadherinas/metabolismo , Cadherinas/genéticaRESUMEN
Centromeres are constricted chromosomal regions that are essential for cell division. In eukaryotes, centromeres display a remarkable architectural and genetic diversity. The basis of centromere-accelerated evolution remains elusive. Here, we focused on Pneumocystis species, a group of mammalian-specific fungal pathogens that form a sister taxon with that of the Schizosaccharomyces pombe, an important genetic model for centromere biology research. Methods allowing reliable continuous culture of Pneumocystis species do not currently exist, precluding genetic manipulation. CENP-A, a variant of histone H3, is the epigenetic marker that defines centromeres in most eukaryotes. Using heterologous complementation, we show that the Pneumocystis CENP-A ortholog is functionally equivalent to CENP-ACnp1 of S. pombe. Using organisms from a short-term in vitro culture or infected animal models and chromatin immunoprecipitation (ChIP)-Seq, we identified CENP-A bound regions in two Pneumocystis species that diverged ~35 million years ago. Each species has a unique short regional centromere (<10 kb) flanked by heterochromatin in 16-17 monocentric chromosomes. They span active genes and lack conserved DNA sequence motifs and repeats. These features suggest an epigenetic specification of centromere function. Analysis of centromeric DNA across multiple Pneumocystis species suggests a vertical transmission at least 100 million years ago. The common ancestry of Pneumocystis and S. pombe centromeres is untraceable at the DNA level, but the overall architectural similarity could be the result of functional constraint for successful chromosomal segregation.IMPORTANCEPneumocystis species offer a suitable genetic system to study centromere evolution in pathogens because of their phylogenetic proximity with the non-pathogenic yeast S. pombe, a popular model for cell biology. We used this system to explore how centromeres have evolved after the divergence of the two clades ~ 460 million years ago. To address this question, we established a protocol combining short-term culture and ChIP-Seq to characterize centromeres in multiple Pneumocystis species. We show that Pneumocystis have short epigenetic centromeres that function differently from those in S. pombe.
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Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Proteína A Centromérica/genética , Filogenia , Proteínas Cromosómicas no Histona/genética , Centrómero/metabolismo , Schizosaccharomyces/genética , ADN/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Saccharomyces cerevisiae/genéticaRESUMEN
The environmental impacts of As mobilization and nitrous oxide (N2O) emission in flooded paddy soils are serious issues for food safety and agricultural greenhouse gas emissions. Several As immobilization strategies utilizing microbially-mediated nitrate reducing-As(III) oxidation (NRAO) and birnessite (δ-MnO2)-induced oxidation/adsorption have proven effective for mitigating As bioavailability in flooded paddy soils. However, several inefficiency and unsustainability issues still exist in these remediation approaches. In this study, the effects of a combined treatment of nitrate and birnessite were assessed for the simultaneous suppression of As(III) mobilization and N2O emission from flooded paddy soils. Microcosm incubations confirmed that the combined treatment achieved an effective suppression of As(III) mobilization and N2O emission, with virtually no As(T) released and at least a 87% decrease in N2O emission compared to nitrate treatment alone after incubating for 8 days. When nitrate and birnessite are co-amended to flooded paddy soils, the activities of denitrifying enzymes within the denitrification electron transport pathway were suppressed by MnO2. As a result, the majority of applied nitrate participated in nitrate-dependent microbial Mn(II) oxidation. The regenerated biogenetic MnO2 was available to facilitate subsequent cycles of As(III) immobilization and concomitant N2O emission suppression, sustainable remediation strategy. Moreover, the combined nitrate-birnessite amendment promoted the enrichment of Pseudomonas, Achromobacter and Cupriavidu, which are known to participate in the oxidation of As(III)/Mn(II). Our findings document strong efficacy for the combined nitrate/birnessite treatment as a remediation strategy to simultaneously mitigate As-pollution and N2O emission, thereby improving food safety and reducing greenhouse gas emissions from flooded paddy soils enriched with NH4+ and As.
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Gases de Efecto Invernadero , Oryza , Suelo , Óxidos , Nitratos/metabolismo , Compuestos de Manganeso , Óxido Nitroso/metabolismo , Oryza/metabolismoRESUMEN
BACKGROUND: P2X3 receptor antagonists hold promising potential as a therapeutic option for patients with refractory or unexplained chronic cough, a condition lacking approved therapies. This study assessed the safety, tolerability, and pharmacokinetics (PK) of HRS-2261, a novel selective P2X3 receptor antagonist, in healthy subjects. METHODS: This randomized, double-blinded, placebo-controlled phase 1 trial of HRS-2261 consisted of three phases: the single ascending dose (SAD) study phase, the food-effect study phase, and the multiple ascending dose (MAD) study phase. In the SAD phase, healthy subjects were randomly assigned to receive a single oral dose of HRS-2261 (25, 100, 200, 400, 800, and 1200 mg) or placebo. Subjects in the 200 mg group of the SAD phase progressed directly to the food-effect phase following safety evaluation. In the MAD phase, healthy subjects were randomized to receive HRS-2261 (50, 200, and 400 mg) or placebo twice daily for 14 consecutive days. The primary endpoints were safety and tolerability. RESULTS: A total of 62 and 30 subjects were enrolled in the SAD and MAD phases, respectively, with 12 subjects from the SAD phase transitioning to the food-effect phase. The incidence and severity of adverse events (AEs) were not dose dependent, and most AEs were mild except for one moderate AE (epididymitis, which was not related to treatment) in the 400 mg group. Dysgeusia was reported in nine subjects, including two from the SAD phase, one from the food-effect phase, and six from the MAD phase. The median Tmax and geometric mean t1/2 were 0.9-2.0 h and 4.1-8.5 h in the SAD, and 2.0-2.7 h and 4.6-5.0 h on day 14 in the MAD, respectively. Drug exposures in the SAD and MAD phases were both less than dose proportional. The accumulation of the drug was slight with repeated twice-daily dosing. Food-effect study results showed that food intake did not affect the plasma exposure of HRS-2261. CONCLUSIONS: HRS-2261 demonstrated good tolerability, with a low incidence of dysgeusia. The PK profile was favorable. This study supports further development of HRS-2261 as a potential P2X3 receptor antagonist for chronic cough. TRIAL REGISTRATION NUMBER: Clinical trials.gov, identifier: NCT05274516. Trial registration date: March 10, 2022.
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Disgeusia , Antagonistas del Receptor Purinérgico P2X , Masculino , Humanos , Antagonistas del Receptor Purinérgico P2X/efectos adversos , Voluntarios Sanos , Relación Dosis-Respuesta a Droga , Área Bajo la Curva , Método Doble CiegoRESUMEN
Fulvic acid (FA) is a representative photosensitive dissolved organic matter (DOM) compound that occurs naturally in paddy soils. In this study, the effect of a FA + nitrate treatment (0, 4 and 8 mg/L FA + 20 mmol/L nitrate) on denitrification and As(III) immobilization in flooded paddy soils was assessed under dark and intermittently illuminated conditions (12 h light+12 h dark). The FA input stimulated denitrification in illuminated soils (~100 % of nitrate removal within 6 days) compared to dark conditions (~92 % nitrate removal after 6 days). Meanwhile, As(III) (initial concentration of 0.1 mmol/L) was nearly completely immobilized (~100 %) under illuminated conditions after 4 days for the FA + nitrate treatment compared to 90- 93 % retention in the dark. Denitrification and As immobilization were positively related to the FA dosage in the illuminated assays. The stronger denitrification in illuminated soils was ascribed to denitrifiers harvesting photoelectrons from photosensitive substrates/semiconducting minerals. FA addition also increased the activities of denitrifying enzymes (e.g., NAR, NIR and NOR) and the denitrification electron transport system by nearly 0.6-0.7 and 1.5-1.8 times that of the nitrate-alone treatment under illuminated and dark conditions, thereby fostering stronger denitrification. Upon irradiation, As(III) immobilization was not only stimulated by the interactions with the denitrification pathway whereby As(III) acts as an electron donor for denitrifiers, but was also modulated by Fe(III)/oxidative reactive species-derived photooxidation of As(III). Moreover, the FA + nitrate treatment promoted the enrichment of metal-oxidizing bacteria (e.g., Stenotrophomonas and Acidovorax) that are responsible for nitrate-dependent As(III)/Fe(II) oxidation. The results of this study enhance our understanding of interactions among the biogeochemical cycles of As, Fe, N and C, which are intricately linked by a biophotoelectrochemical pathway in flooded paddy soils.
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Benzopiranos , Desnitrificación , Nitratos , Nitratos/metabolismo , Compuestos Férricos , Suelo/química , Oxidación-ReducciónRESUMEN
BACKGROUND: Little is known about the changes and mechanisms of intestinal flora in primary immune thrombocytopenia (ITP) patients. AIM: To explore the structural and functional differences of intestinal flora between ITP patients and healthy controls, and clarify the correlation between intestinal flora and Th1/Th2 imbalance. METHODS: Feces from ITP patients and healthy controls were studied by 16S rRNA and metagenomic techniques at phylum, genus, species or functional levels. Blood samples were collected for the detection of interleukin -2 (IL-2) and IL-4 concentrations. RESULTS: The following changes in ITP patients were found: a decrease of Bacteroidetes phylum, an increase of Proteobacteria phylum and alterations of ten genera and 1045 species. IL-2 and IL-4 were significantly correlated with six and five genera, respectively. Species of C. freundii, C. rodentium, and C. youngae were negatively correlated with bleeding scores, and S. infantis was positively related to platelet counts. Functionally, the intestinal flora of ITP patients changed mainly in terms of motility, chemotaxis, membrane transport, and metabolism. CONCLUSION: The mechanism underlying functional and structural changes of intestinal flora in ITP patients may be related to inflammation and immunity, providing possibilities of probiotics or fecal transplants for ITP.
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Microbioma Gastrointestinal , Púrpura Trombocitopénica Idiopática , Humanos , Interleucina-2 , Interleucina-4 , ARN Ribosómico 16SRESUMEN
Neural progenitor cells (NPCs) are essential for in vitro drug screening and cell-based therapies for brain-related disorders, necessitating well-defined and reproducible culture systems. Current strategies employing protein growth factors pose challenges in terms of both reproducibility and cost. In this study, we developed a novel DNA-based modulator to regulate FGFR signaling in NPCs, thereby facilitating the long-term maintenance of stemness and promoting neurogenesis. This DNA-based FGFR-agonist effectively stimulated FGFR1 phosphorylation and activated the downstream ERK signaling pathway in human embryonic stem cell (HESC)-derived NPCs. We replaced the basic fibroblast growth factor (bFGF) in the culture medium with our DNA-based FGFR-agonist to artificially modulate FGFR signaling in NPCs. Utilizing a combination of cell experiments and bioinformatics analyses, we showed that our FGFR-agonist could enhance NPC proliferation, direct migration, and promote neurosphere formation, thus mimicking the functions of bFGF. Notably, transcriptomic analysis indicated that the FGFR-agonist could specifically influence the transcriptional program associated with stemness while maintaining the neuronal differentiation program, closely resembling the effects of bFGF. Furthermore, our culture conditions allowed for the successful propagation of NPCs through over 50 passages while retaining their ability to efficiently differentiate into neurons. Collectively, our approach offers a highly effective method for expanding NPCs, thereby providing new avenues for disease-in-dish research and drug screening aimed at combating neural degeneration.
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Células Madre Embrionarias Humanas , Células-Madre Neurales , Humanos , Reproducibilidad de los Resultados , Células-Madre Neurales/metabolismo , Neurogénesis/fisiología , ADN/metabolismo , ADN/farmacología , Diferenciación Celular , Células CultivadasRESUMEN
Quinary RuRhPdPtAu high-entropy alloy nanoparticles (HEA-NPs) were prepared for the first time from a deep eutectic solvent by an electrochemical method. Owing to the benefits of high entropy and abundant surface active sites, the RuRhPdPtAu HEA-NPs exhibit outstanding electrocatalytic performance for the hydrogen evolution reaction.
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Cyanobacteria, one of the most widespread photoautotrophic microorganisms on Earth, have evolved an inorganic CO2-concentrating mechanism (CCM) to adapt to a variety of habitats, especially in CO2-limited environments. Leptolyngbya boryana, a filamentous cyanobacterium, is widespread in a variety of environments and is well adapted to low-inorganic-carbon environments. However, little is currently known about the CCM of L. boryana, in particular its efficient carbon fixation module. In this study, we isolated and purified the cyanobacterium CZ1 from the Xin'anjiang River basin and identified it as L. boryana by 16S rRNA sequencing. Genome analysis revealed that L. boryana CZ1 contains ß-carboxysome shell proteins and form 1B of Rubisco, which is classify it as belonging to the ß-cyanobacteria. Further analysis revealed that L. boryana CZ1 employs a fine CCM involving two CO2 uptake systems NDH-13 and NDH-14, three HCO3- transporters (SbtA, BicA, and BCT1), and two carboxysomal carbonic anhydrases. Notably, we found that NDH-13 and NDH-14 are located close to each other in the L. boryana CZ1 genome and are back-to-back with the ccm operon, which is a novel gene arrangement. In addition, L. boryana CZ1 encodes two high-affinity Na+/HCO3- symporters (SbtA1 and SbtA2), three low-affinity Na+-dependent HCO3- transporters (BicA1, BicA2, and BicA3), and a BCT1; it is rare for a single strain to encode all three bicarbonate transporters in such large numbers. Interestingly, L. boryana CZ1 also uniquely encodes two active carbonic anhydrases, CcaA1 and CcaA2, which are also rare. Taken together, all these results indicated that L. boryana CZ1 is more efficient at CO2 fixation. Moreover, compared with the reported CCM gene arrangement of cyanobacteria, the CCM-related gene distribution pattern of L. boryana CZ1 was completely different, indicating a novel gene organization structure. These results can enrich our understanding of the CCM-related gene arrangement of cyanobacteria, and provide data support for the subsequent improvement and increase in biomass through cyanobacterial photosynthesis.
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Full-Heusler alloys (fHAs) exhibit high mechanical strength with earth-abundant elements, but their metallic properties tend to display small electron diffusion thermopower, limiting potential applications as excellent thermoelectric (TE) materials. Here, it is demonstrated that the Co-based fHAs Co2 XAl (X = Ti, V, Nb) exhibit relatively high thermoelectric performance due to spin and charge coupling. Thermopower contributions from different magnetic mechanisms, including spin fluctuation and magnon drag are extracted. A significant contribution to thermopower from magnetism compared to that from electron diffusion is demonstrated. In Co2 TiAl, the contribution to thermopower from spin fluctuation is higher than that from electron diffusion, resulting in an increment of 280 µW m-1 K-2 in the power factor value. Interestingly, the thermopower contribution from magnon drag can reach up to -47 µV K-1 , which is over 2400% larger than the electron diffusion thermopower. The power factor of Co2 TiAl can reach 4000 µW m-1 K-2 which is comparable to that of conventional semiconducting TE materials. Moreover, the corresponding figure of merit zT can reach ≈0.1 at room temperature, which is significantly larger than that of traditional metallic materials. The work shows a promising unconventional way to create and optimize TE materials by introducing magnetism.
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Centromeres are genomic regions that coordinate accurate chromosomal segregation during mitosis and meiosis. Yet, despite their essential function, centromeres evolve rapidly across eukaryotes. Centromeres are often the sites of chromosomal breaks which contribute to genome shuffling and promote speciation by inhibiting gene flow. How centromeres form in strongly host-adapted fungal pathogens has yet to be investigated. Here, we characterized the centromere structures in closely related species of mammalian-specific pathogens of the fungal phylum of Ascomycota. Methods allowing reliable continuous culture of Pneumocystis species do not currently exist, precluding genetic manipulation. CENP-A, a variant of histone H3, is the epigenetic marker that defines centromeres in most eukaryotes. Using heterologous complementation, we show that the Pneumocystis CENP-A ortholog is functionally equivalent to CENP-ACnp1 of Schizosaccharomyces pombe. Using organisms from a short-term in vitro culture or infected animal models and ChIP-seq, we identified centromeres in three Pneumocystis species that diverged ~100 million years ago. Each species has a unique short regional centromere (< 10kb) flanked by heterochromatin in 16-17 monocentric chromosomes. They span active genes and lack conserved DNA sequence motifs and repeats. CENP-C, a scaffold protein that links the inner centromere to the kinetochore appears dispensable in one species, suggesting a kinetochore rewiring. Despite the loss of DNA methyltransferases, 5-methylcytosine DNA methylation occurs in these species, though not related to centromere function. These features suggest an epigenetic specification of centromere function.
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MicroRNAs (miRNAs) have emerged as promising diagnostic biomarkers and therapeutic targets in various diseases. However, there is currently a lack of molecular strategies that can effectively use disease-associated extracellular miRNAs as input signals to drive therapeutic functions. Herein, we present a modular and programmable miRNA-responsive chimeric DNA receptor (miRNA-CDR) capable of biomarker-driven therapy. By grafting a miRNA-responsive DNA nanodevice on a natural membrane receptor via aptamer anchoring, miRNA-CDR can sense extracellular miRNA levels and autonomously induce dimerization-mediated receptor activation via the complementary-mediated strand displacement reaction-induced dynamic DNA assembly. The sequence programmability of miRNA-CDR allows it to sense and respond to a user-defined miRNA with tunable sensitivity. Moreover, the miRNA-CDR is versatile and customizable to reprogram desirable signaling output via adapting a designated receptor, such as MET and FGFR1. Using a mouse model of drug-induced acute liver injury (DILI), we demonstrate the functionality of a designer miRNA-CDR in rewiring the recognition of the DILI-elevated miR-122 to promote MET signaling of hepatocytes for biomarker-driven in situ repair and liver function restoration. Our synthetic miRNA-CDR platform provides a novel molecular device enabling biomarker-driven therapeutic cellular response, potentially paving the way for improving the precision of cell therapy in regenerative medicine.
Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , MicroARNs , Receptores Artificiales , Humanos , MicroARNs/genética , Biomarcadores , Hepatocitos , ADNRESUMEN
BACKGROUND AND OBJECTIVE: There is an unmet need for a safer anticoagulant since bleeding remains a concern with currently approved anticoagulants. Coagulation factor XI (FXI) is an attractive anticoagulant drug target with limited a role in physiological hemostasis. The objective of this study was to evaluate the safety, pharmacokinetics, and pharmacodynamics of SHR2285, a novel small molecule FXIa inhibitor, in healthy Chinese volunteers. METHODS: The study consisted of single ascending doses part (part 1: 25-600 mg) and multiple ascending doses part (part 2: 100, 200, 300, and 400 mg). In both parts, subjects were randomized in a 3:1 ratio to receive SHR2285 or placebo orally. Blood, urine and feces samples were collected to describe its pharmacokinetic and pharmacodynamic profile. RESULTS: In total, 103 healthy volunteers completed the study. SHR2285 was well tolerated. SHR2285 was absorbed rapidly with median time to maximum plasma concentration (Tmax) of 1.50 to 3.00 h. The geometric median half-life (t1/2) of SHR2285 varied from 8.74 to 12.1 h across 25-600 mg single dose. Total systemic exposure of metabolite SHR164471 was approximately 1.77- to 3.61-fold that of the parent drug. The plasma concentration of SHR2285 and SHR164471 reached steady state by the morning of Day 7, with low accumulation ratio (0.956-1.20 and 1.18-1.56, respectively). The increase in pharmacokinetic exposure of SHR2285 and SHR164471 was less than dose proportional. Food has minimal effect on the pharmacokinetics of SHR2285 and SHR164471. SHR2285 produced an exposure-dependent prolongation of activated partial thromboplastin time (APTT) and a decrease in FXI activity. The maximum FXI activity inhibition rate (geometric mean) at steady state was 73.27%, 85.58%, 87.77% and 86.27% for 100-400 mg, respectively. CONCLUSIONS: SHR2285 was generally safe and well tolerated in healthy subjects across a wide range of doses. SHR2285 exhibited a predictable pharmacokinetic profile and an exposure-related pharmacodynamic profile. CLINICALTRIALS: gov Identifier NCT04472819; registered on July 15, 2020.