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1.
EMBO J ; 42(17): e113415, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37485728

RESUMEN

The human ABC transporter ABCC3 (also known as MRP3) transports a wide spectrum of substrates, including endogenous metabolites and exogenous drugs. Accordingly, it participates in multiple physiological processes and is involved in diverse human diseases such as intrahepatic cholestasis of pregnancy, which is caused by the intracellular accumulation of bile acids and estrogens. Here, we report three cryogenic electron microscopy structures of ABCC3: in the apo-form and in complexed forms bound to either the conjugated sex hormones ß-estradiol 17-(ß-D-glucuronide) and dehydroepiandrosterone sulfate. For both hormones, the steroid nuclei that superimpose against each other occupy the hydrophobic center of the transport cavity, whereas the two conjugation groups are separated and fixed by the hydrophilic patches in two transmembrane domains. Structural analysis combined with site-directed mutagenesis and ATPase activity assays revealed that ABCC3 possesses an amphiphilic substrate-binding pocket able to hold either conjugated hormone in an asymmetric pattern. These data build on consensus features of the substrate-binding pocket of MRPs and provide a structural platform for the rational design of inhibitors.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Estradiol , Humanos , Transportadoras de Casetes de Unión a ATP/genética , Estradiol/farmacología , Estradiol/metabolismo , Mutagénesis Sitio-Dirigida
2.
Proc Natl Acad Sci U S A ; 121(7): e2315476121, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38319970

RESUMEN

Marine photosynthetic dinoflagellates are a group of successful phytoplankton that can form red tides in the ocean and also symbiosis with corals. These features are closely related to the photosynthetic properties of dinoflagellates. We report here three structures of photosystem I (PSI)-chlorophylls (Chls) a/c-peridinin protein complex (PSI-AcpPCI) from two species of dinoflagellates by single-particle cryoelectron microscopy. The crucial PsaA/B subunits of a red tidal dinoflagellate Amphidinium carterae are remarkably smaller and hence losing over 20 pigment-binding sites, whereas its PsaD/F/I/J/L/M/R subunits are larger and coordinate some additional pigment sites compared to other eukaryotic photosynthetic organisms, which may compensate for the smaller PsaA/B subunits. Similar modifications are observed in a coral symbiotic dinoflagellate Symbiodinium species, where two additional core proteins and fewer AcpPCIs are identified in the PSI-AcpPCI supercomplex. The antenna proteins AcpPCIs in dinoflagellates developed some loops and pigment sites as a result to accommodate the changed PSI core, therefore the structures of PSI-AcpPCI supercomplex of dinoflagellates reveal an unusual protein assembly pattern. A huge pigment network comprising Chls a and c and various carotenoids is revealed from the structural analysis, which provides the basis for our deeper understanding of the energy transfer and dissipation within the PSI-AcpPCI supercomplex, as well as the evolution of photosynthetic organisms.


Asunto(s)
Antozoos , Dinoflagelados , Animales , Antozoos/metabolismo , Complejos de Proteína Captadores de Luz/metabolismo , Dinoflagelados/metabolismo , Floraciones de Algas Nocivas , Simbiosis , Microscopía por Crioelectrón , Complejo de Proteína del Fotosistema I/metabolismo , Clorofila/metabolismo
3.
PLoS Pathog ; 20(9): e1012533, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39231185

RESUMEN

The body temperature of Warm-blooded hosts impedes and informs responses of bacteria accustomed to cooler environments. The second messenger c-di-GMP modulates bacterial behavior in response to diverse, yet largely undiscovered, stimuli. A long-standing debate persists regarding whether a local or a global c-di-GMP pool plays a critical role. Our research on a Stenotrophomonas maltophilia strain thriving at around 28°C, showcases BtsD as a thermosensor, diguanylate cyclase, and effector. It detects 37°C and diminishes c-di-GMP synthesis, resulting in a responsive sequence: the periplasmic c-di-GMP level is decreased, the N-terminal region of BtsD disengages from c-di-GMP, activates the two-component signal transduction system BtsKR, and amplifies sod1-3 transcription, thereby strengthening the bacterium's pathogenicity and adaptation during infections in 37°C warm Galleria mellonella larvae. This revelation of a single-protein c-di-GMP module introduces unrecognized dimensions to the functional and structural paradigms of c-di-GMP modules and reshapes our understanding of bacterial adaptation and pathogenicity in hosts with a body temperature around 37°C. Furthermore, the discovery of a periplasmic c-di-GMP pool governing BtsD-BtsK interactions supports the critical role of a local c-di-GMP pool.


Asunto(s)
Proteínas Bacterianas , GMP Cíclico , Infecciones por Bacterias Gramnegativas , Stenotrophomonas maltophilia , Stenotrophomonas maltophilia/metabolismo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Animales , Infecciones por Bacterias Gramnegativas/microbiología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Transducción de Señal , Temperatura Corporal/fisiología , Regulación Bacteriana de la Expresión Génica , Liasas de Fósforo-Oxígeno/metabolismo , Liasas de Fósforo-Oxígeno/genética
4.
J Virol ; 98(3): e0191523, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38334327

RESUMEN

As an intrinsic cellular mechanism responsible for the internalization of extracellular ligands and membrane components, caveolae-mediated endocytosis (CavME) is also exploited by certain pathogens for endocytic entry [e.g., Newcastle disease virus (NDV) of paramyxovirus]. However, the molecular mechanisms of NDV-induced CavME remain poorly understood. Herein, we demonstrate that sialic acid-containing gangliosides, rather than glycoproteins, were utilized by NDV as receptors to initiate the endocytic entry of NDV into HD11 cells. The binding of NDV to gangliosides induced the activation of a non-receptor tyrosine kinase, Src, leading to the phosphorylation of caveolin-1 (Cav1) and dynamin-2 (Dyn2), which contributed to the endocytic entry of NDV. Moreover, an inoculation of cells with NDV-induced actin cytoskeletal rearrangement through Src to facilitate NDV entry via endocytosis and direct fusion with the plasma membrane. Subsequently, unique members of the Rho GTPases family, RhoA and Cdc42, were activated by NDV in a Src-dependent manner. Further analyses revealed that RhoA and Cdc42 regulated the activities of specific effectors, cofilin and myosin regulatory light chain 2, responsible for actin cytoskeleton rearrangement, through diverse intracellular signaling cascades. Taken together, our results suggest that an inoculation of NDV-induced Src-mediated cellular activation by binding to ganglioside receptors. This process orchestrated NDV endocytic entry by modulating the activities of caveolae-associated Cav1 and Dyn2, as well as specific Rho GTPases and downstream effectors. IMPORTANCE: In general, it is known that the paramyxovirus gains access to host cells through direct penetration at the plasma membrane; however, emerging evidence suggests more complex entry mechanisms for paramyxoviruses. The endocytic entry of Newcastle disease virus (NDV), a representative member of the paramyxovirus family, into multiple types of cells has been recently reported. Herein, we demonstrate the binding of NDV to induce ganglioside-activated Src signaling, which is responsible for the endocytic entry of NDV through caveolae-mediated endocytosis. This process involved Src-dependent activation of the caveolae-associated Cav1 and Dyn2, as well as specific Rho GTPase and downstream effectors, thereby orchestrating the endocytic entry process of NDV. Our findings uncover a novel molecular mechanism of endocytic entry of NDV into host cells and provide novel insight into paramyxovirus mechanisms of entry.


Asunto(s)
Macrófagos , Enfermedad de Newcastle , Virus de la Enfermedad de Newcastle , Transducción de Señal , Internalización del Virus , Animales , Endocitosis , Gangliósidos/metabolismo , Macrófagos/metabolismo , Macrófagos/virología , Enfermedad de Newcastle/virología , Virus de la Enfermedad de Newcastle/fisiología , Proteínas de Unión al GTP rho/metabolismo
5.
J Biol Chem ; 299(8): 105057, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37468106

RESUMEN

In wild-type phototrophic organisms, carotenoids (Crts) are primarily packed into specific pigment-protein complexes along with (Bacterio)chlorophylls and play important roles in the photosynthesis. Diphenylamine (DPA) inhibits carotenogenesis but not phototrophic growth of anoxygenic phototrophs and eliminates virtually all Crts from photocomplexes. To investigate the effect of Crts on assembly of the reaction center-light-harvesting (RC-LH) complex from the filamentous anoxygenic phototroph Roseiflexus (Rfl.) castenholzii, we generated carotenoidless (Crt-less) RC-LH complexes by growing cells in the presence of DPA. Here, we present cryo-EM structures of the Rfl. castenholzii native and Crt-less RC-LH complexes with resolutions of 2.86 Å and 2.85 Å, respectively. From the high-quality map obtained, several important but previously unresolved details in the Rfl. castenholzii RC-LH structure were determined unambiguously including the assignment and likely function of three small polypeptides, and the content and spatial arrangement of Crts with bacteriochlorophyll molecules. The overall structures of Crt-containing and Crt-less complexes are similar. However, structural comparisons showed that only five Crts remain in complexes from DPA-treated cells and that the subunit X (TMx) flanked on the N-terminal helix of the Cyt-subunit is missing. Based on these results, the function of Crts in the assembly of the Rfl. castenholzii RC-LH complex and the molecular mechanism of quinone exchange is discussed. These structural details provide a fresh look at the photosynthetic apparatus of an evolutionary ancient phototroph as well as new insights into the importance of Crts for proper assembly and functioning of the RC-LH complex.


Asunto(s)
Proteínas Bacterianas , Chloroflexi , Fotosíntesis , Proteínas Bacterianas/metabolismo , Carotenoides/metabolismo , Chloroflexi/metabolismo , Complejos de Proteína Captadores de Luz/química
6.
Clin Immunol ; 265: 110264, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38825072

RESUMEN

Rheumatoid arthritis (RA) is a systemic chronic autoimmune disease that primarily affects the joints and surrounding soft tissues, characterized by chronic inflammation and proliferation of the synovium. Various immune cells are involved in the pathophysiology of RA. The complex interplay of factors such as chronic inflammation, genetic susceptibility, dysregulation of serum antibody levels, among others, contribute to the complexity of the disease mechanism, disease activity, and treatment of RA. Recently, the cytokine storm leading to increased disease activity in RA has gained significant attention. Interleukin-33 (IL-33), a member of the IL-1 family, plays a crucial role in inflammation and immune regulation. ST2 (suppression of tumorigenicity 2 receptor), the receptor for IL-33, is widely expressed on the surface of various immune cells. When IL-33 binds to its receptor ST2, it activates downstream signaling pathways to exert immunoregulatory effects. In RA, IL-33 regulates the progression of the disease by modulating immune cells such as circulating monocytes, tissue-resident macrophages, synovial fibroblasts, mast cells, dendritic cells, neutrophils, T cells, B cells, endothelial cells, and others. We have summarized and analyzed these findings to elucidate the pathways through which IL-33 regulates RA. Furthermore, IL-33 has been detected in the synovium, serum, and synovial fluid of RA patients. Due to inconsistent research results, we conducted a meta-analysis on the association between serum IL-33, synovial fluid IL-33, and the risk of developing RA in patients. The pooled SMD was 1.29 (95% CI: 1.15-1.44), indicating that IL-33 promotes the onset and pathophysiological progression of RA. Therefore, IL-33 may serve as a biomarker for predicting the risk of developing RA and treatment outcomes. As existing drugs for RA still cannot address drug resistance in some patients, new therapeutic approaches are needed to alleviate the significant burden on RA patients and healthcare systems. In light of this, we analyzed the potential of targeting the IL-33/ST2-related signaling pathway to modulate immune cells associated with RA and alleviate inflammation. We also reviewed IL-33 and RA susceptibility-related single nucleotide polymorphisms, suggesting potential involvement of IL-33 and macrophage-related drug-resistant genes in RA resistance therapy. Our review elucidates the role of IL-33 in the pathophysiology of RA, offering new insights for the treatment of RA.


Asunto(s)
Artritis Reumatoide , Interleucina-33 , Animales , Humanos , Artritis Reumatoide/inmunología , Proteína 1 Similar al Receptor de Interleucina-1/genética , Proteína 1 Similar al Receptor de Interleucina-1/inmunología , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Interleucina-33/inmunología , Transducción de Señal/inmunología
7.
Br J Haematol ; 205(2): 594-606, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38685577

RESUMEN

Multiple myeloma (MM) is an incurable plasma cell cancer in the bone marrow. Immunomodulatory drugs, such as lenalidomide (LEN) and pomalidomide, are backbone agents in MM treatment, and LEN resistance is commonly seen in the MM clinic. In this study, we presented that heterogeneous nuclear ribonucleoprotein U (hnRNPU) affected MM resistance to LEN via the regulation of target mRNA translation. hnRNPULow MM cells exhibited upregulated CRBN and IKZF1 proteins, stringent IKZF1/3 protein degradation upon LEN addition and increased sensitivity to LEN. RNA pulldown assays and RNA electrophoretic mobility shift assays revealed that hnRNPU bound to the 3'-untranslated region of CRBN and IKZF1 mRNA. A sucrose gradient assay suggested that hnRNPU specifically regulated CRBN and IKZF1 mRNA translation. The competition of hnRNPU binding to its target mRNAs by small RNAs with hnRNPU-binding sites restored MM sensitivity to LEN. hnRNPU function in vivo was confirmed in an immunocompetent MM mouse model constructed by the inoculation of Crbn-humanized murine 5TGM1 cells into CrbnI391V/+ mice. Overall, this study suggests a novel mechanism of LEN sensitivity in which hnRNPU represses CRBN and IKZF1 mRNA translation.


Asunto(s)
Lenalidomida , Mieloma Múltiple , Lenalidomida/farmacología , Lenalidomida/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Humanos , Ratones , Animales , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Factor de Transcripción Ikaros/genética , Factor de Transcripción Ikaros/metabolismo
8.
J Gene Med ; 26(7): e3712, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38949072

RESUMEN

Aggrephagy, a type of autophagy, degrades the aggregation of misfolded protein in cells. However, the role of aggrephagy in multiple myeloma (MM) has not been fully demonstrated. In this study, we first investigated the correlation between aggrephagy signaling, MM immune microenvironment composition and disease prognosis. Single-cell RNA-seq data, including the expression profiles of 12,187 single cells from seven MM bone marrow (BM) and seven healthy BM samples, were analyzed by non-negative matrix factorization for 44 aggrephagy-related genes. Bulk RNA-seq cohorts from the Gene Expression Omnibus database were used to evaluate the prognostic value of aggrephagy-related immune cell subtypes and predict immune checkpoint blockade immunotherapeutic response in MM. Compared with healthy BM, MM BM exhibited different patterns of aggrephagy-related gene expression. In MM BM, macrophages, CD8+ T cells, B cells and natural killer cells could be grouped into four to nine aggrephagy-related subclusters. The signature of aggrephagy signaling molecule expression in the immune cells correlates with the patient's prognosis. Our investigation provides a novel view of aggrephagy signaling in MM tumor microenvironment cells, which might be a prognostic indicator and potential target for MM treatment.


Asunto(s)
Mieloma Múltiple , Transducción de Señal , Análisis de la Célula Individual , Microambiente Tumoral , Mieloma Múltiple/genética , Mieloma Múltiple/inmunología , Humanos , Microambiente Tumoral/inmunología , Microambiente Tumoral/genética , Análisis de la Célula Individual/métodos , Pronóstico , Regulación Neoplásica de la Expresión Génica , Autofagia/genética , Autofagia/inmunología , Perfilación de la Expresión Génica/métodos , Biomarcadores de Tumor/genética , Transcriptoma
9.
Small ; : e2403409, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38934349

RESUMEN

Acute myeloid leukemia (AML) is a common and catastrophic hematological neoplasm with high mortality rates. Conventional therapies, including chemotherapy, hematopoietic stem cell transplantation (HSCT), immune therapy, and targeted agents, have unsatisfactory outcomes for AML patients due to drug toxicity, off-target effects, drug resistance, drug side effects, and AML relapse and refractoriness. These intrinsic limitations of current treatments have promoted the development and application of nanomedicine for more effective and safer leukemia therapy. In this review, the classification of nanoparticles applied in AML therapy, including liposomes, polymersomes, micelles, dendrimers, and inorganic nanoparticles, is reviewed. In addition, various strategies for enhancing therapeutic targetability in nanomedicine, including the use of conjugating ligands, biomimetic-nanotechnology, and bone marrow targeting, which indicates the potential to reverse drug resistance, are discussed. The application of nanomedicine for assisting immunotherapy is also involved. Finally, the advantages and possible challenges of nanomedicine for the transition from the preclinical phase to the clinical phase are discussed.

10.
BMC Cancer ; 24(1): 613, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773461

RESUMEN

BACKGROUND: The intricate balance between the advantages and risks of low-dose computed tomography (LDCT) impedes the utilization of lung cancer screening (LCS). Guiding shared decision-making (SDM) for well-informed choices regarding LCS is pivotal. There has been a notable increase in research related to SDM. However, these studies possess limitations. For example, they may ignore the identification of decision support and needs from the perspective of health care providers and high-risk groups. Additionally, these studies have not adequately addressed the complete SDM process, including pre-decisional needs, the decision-making process, and post-decision experiences. Furthermore, the East-West divide of SDM has been largely ignored. This study aimed to explore the decisional needs and support for shared decision-making for LCS among health care providers and high-risk groups in China. METHODS: Informed by the Ottawa Decision-Support Framework, we conducted qualitative, face-to-face in-depth interviews to explore shared decision-making among 30 lung cancer high-risk individuals and 9 health care providers. Content analysis was used for data analysis. RESULTS: We identified 4 decisional needs that impair shared decision-making: (1) LCS knowledge deficit; (2) inadequate supportive resources; (3) shared decision-making conceptual bias; and (4) delicate doctor-patient bonds. We identified 3 decision supports: (1) providing information throughout the LCS process; (2) providing shared decision-making decision coaching; and (3) providing decision tools. CONCLUSIONS: This study offers valuable insights into the decisional needs and support required to undergo LCS among high-risk individuals and perspectives from health care providers. Future studies should aim to design interventions that enhance the quality of shared decision-making by offering LCS information, decision tools for LCS, and decision coaching for shared decision-making (e.g., through community nurses). Simultaneously, it is crucial to assess individuals' needs for effective deliberation to prevent conflicts and regrets after arriving at a decision.


Asunto(s)
Toma de Decisiones Conjunta , Detección Precoz del Cáncer , Personal de Salud , Neoplasias Pulmonares , Investigación Cualitativa , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagen , Masculino , Femenino , China , Persona de Mediana Edad , Detección Precoz del Cáncer/psicología , Detección Precoz del Cáncer/métodos , Personal de Salud/psicología , Anciano , Tomografía Computarizada por Rayos X/métodos , Adulto , Participación del Paciente
11.
J Biomed Sci ; 31(1): 11, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38245749

RESUMEN

Liquid-liquid phase separation (LLPS) in biology describes a process by which proteins form membraneless condensates within a cellular compartment when conditions are met, including the concentration and posttranslational modifications of the protein components, the condition of the aqueous solution (pH, ionic strength, pressure, and temperature), and the existence of assisting factors (such as RNAs or other proteins). In these supramolecular liquid droplet-like inclusion bodies, molecules are held together through weak intermolecular and/or intramolecular interactions. With the aid of LLPS, cells can assemble functional sub-units within a given cellular compartment by enriching or excluding specific factors, modulating cellular function, and rapidly responding to environmental or physiological cues. Hence, LLPS is emerging as an important means to regulate biology and physiology. Yet, excessive inclusion body formation by, for instance, higher-than-normal concentrations or mutant forms of the protein components could result in the conversion from dynamic liquid condensates into more rigid gel- or solid-like aggregates, leading to the disruption of the organelle's function followed by the development of human disorders like neurodegenerative diseases. In summary, well-controlled formation and de-formation of LLPS is critical for normal biology and physiology from single cells to individual organisms, whereas abnormal LLPS is involved in the pathophysiology of human diseases. In turn, targeting these aggregates or their formation represents a promising approach in treating diseases driven by abnormal LLPS including those neurodegenerative diseases that lack effective therapies.


Asunto(s)
Enfermedades Neurodegenerativas , Separación de Fases , Humanos , Proteínas
12.
Chemphyschem ; : e202400628, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39292518

RESUMEN

The burgeoning field of frustrated Lewis pair (FLP) heterogeneous catalysts has garnered significant interest in recent years, primarily due to their inherent ability to activate H-source molecules, such as H2, thereby facilitating hydrogenation reactions. However, the application of single metal atom catalysts incorporating FLP sites has been relatively under-explored. In this study, non-precious transition metal atoms were anchored onto a C2N framework with an intrinsic cavity and a defective N-C sheet. Theoretical calculations substantiated energy barriers as low as 0.10 eV for isopropanol activation, thereby positioning these catalysts as highly promising candidates for catalytic transfer hydrogenation of furfural. Electronic structure analyses revealed that the H-O bond breakage in isopropanol molecules was significantly facilitated by the presence of FLP sites within the catalysts. Notably, both Ni-C2N and Ni-N6-C demonstrated exceptional potential as selective catalysts for the hydrogenation of furfural into furfuryl alcohol, exhibiting remarkably low barriers of only 0.65-0.72 eV for the rate-determining steps, which are notably lower than those observed in many traditional catalysts. Theoretical investigations strongly imply that the construction of single atom catalysts with FLP sites could significantly enhance the activity and selectivity for hydrogenation reactions, thus stimulating the experimental synthesis of such catalysts.

13.
Amino Acids ; 56(1): 16, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38358574

RESUMEN

Antimicrobial peptide (AMP) is the polypeptide, which protects the organism avoiding attack from pathogenic bacteria. Studies have shown that there were some antimicrobial peptides with molecular action mechanism involved in crossing the cell membrane without inducing severe membrane collapse, then interacting with cytoplasmic target-nucleic acid, and exerting antibacterial activity by interfacing the transmission of genetic information of pathogenic microorganisms. However, the relationship between the antibacterial activities and peptide structures was still unclear. Therefore, in the present work, a series of AMPs with a sequence of 20 amino acids was extracted from DBAASP database, then, quantitative structure-activity relationship (QSAR) methods were conducted on these peptides. In addition, novel antimicrobial peptides with  stronger antimicrobial activities were designed according to the information originated from the constructed models. Hence, the outcome of this study would lay a solid foundation for the in-silico design and exploration of novel antibacterial peptides with improved activity activities.


Asunto(s)
Péptidos , Relación Estructura-Actividad Cuantitativa , Péptidos/farmacología , Péptidos Antimicrobianos , Aminoácidos , Antibacterianos/farmacología
14.
Langmuir ; 40(28): 14594-14601, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38943597

RESUMEN

Methylammonium lead halide perovskites with highly efficient pure-color or white-light generation have gained increasing scientific interest and promote the development of a great commercial opportunity in displays, lighting, and other applications. However, the poor stabilities, lead toxicity, and unfriendly solvents and ligands in the growth process severely restrict their commercial application. Here, we proposed a green method for preparing uniform and stable polymer-encapsulated photoluminescence (PL) tunable CH3NH3PbBr3-xClx NC thin films at room temperature. Utilizing the swelling effect between alcohol compounds and organic polymers and the ionization of NaCl in methanol solution, the anion exchange process can be achieved rapidly within 7 min. Moreover, the PL wavelengths of the CH3NH3PbBr3-xClx NCs films were precisely tuned with steps as fine as 2 nm. Experimental results showed that NaCl dissolved in methanol solution can form Cl-(CH3OH)n, which brings ionized Cl into the polymer-encapsulated CH3NH3PbBr3 NCs film for CH3NH3PbBr3-xClx NCs film growth. Based on the swelling and anion exchange dynamics, a modified NaCl-CH3OH-MABr solution system was developed to trigger CH3NH3PbBr3-xClx NCs film PL emission tuning from 528 to 463 nm with several-fold intensity enhancement. The realization of precisely controlled photoluminescence from the perovskite nanocrystal film would have wide applications in the optical and imaging fields.

15.
Anal Bioanal Chem ; 416(22): 5013-5023, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38997460

RESUMEN

Therapeutic drug monitoring is essential for ensuring the efficacy and safety of medications. This study introduces a streamlined approach that combines pipette-tip solid-phase extraction (PT-SPE) with matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), facilitating rapid and high-throughput monitoring of drug concentrations. As a demonstration, this method was applied to the extraction and quantification of antidepressants in serum. Utilizing Zip-Tip C18, the method enabled the extraction of antidepressants from complex biological matrices in less than 2 min, with the subsequent MALDI-MS analysis yielding results in just 1 min. Optimal extraction recoveries were achieved using a sampling solution at pH 9.0 and a 10 µL ethanol desorption solution containing 0.1% phosphoric acid. For MALDI analysis, 2,5-dihydroxybenzoic acid was identified as the most effective matrix for producing the highest signal intensity. The quantification strategy exhibited robust linearities (R2 ≥ 0.997) and satisfactory limits of quantification, ranging from 0.05 to 0.5 µg/mL for a suite of antidepressants. The application for monitoring dynamic concentration changes of antidepressants in rat serum emphasized the method's efficacy. This strategy offers the advantages of high throughput, minimal sample usage, environmental sustainability, and simplicity, providing ideas and a reference basis for the subsequent development of methods for therapeutic drug monitoring.


Asunto(s)
Antidepresivos , Extracción en Fase Sólida , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Extracción en Fase Sólida/métodos , Animales , Antidepresivos/sangre , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Ratas , Límite de Detección , Ensayos Analíticos de Alto Rendimiento/métodos , Ratas Sprague-Dawley , Monitoreo de Drogas/métodos , Masculino
16.
J Asthma ; 61(4): 271-281, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37851868

RESUMEN

OBJECTIVE: This study aimed to investigate the potential anti-inflammatory and antioxidant effects of apigenin in rats with acute lung injury (ALI). We also examined changes in levels of inflammatory and antioxidant factors after apigenin treatment in a rat model of ALI.Methods: We searched several databases, including PubMed, Scopus, EMBASE, Web of Science, ProQuest, and GoogleScholar, to retrieve relevant articles for our systematic review and meta-analysis.Five studies with 226 rat models of ALI were included in this study. We investigated inflammatory factors and oxidative stress with the corresponding 95% confidence interval in three groups: 1. Group1 (control vs. ALI), 2. Group2 (ALI vs. apigenin10), and 3. Group3 (ALI vs. apigenin20). RESULTS: Estimating the correlation and 95% confidence intervals for the inflammatory agents and oxidative stress in the intervention group (ALI), compared with that in the control group, respectively (correlation: 0.194; 95% confidence intervals, 0.101-0.282, p value = .001, z-value= 4.08) and (correlation: 0.099; 95% confidence intervals, 0.016-0.182, p value = .020, z value= 2.325). Estimating the correlation and 95% confidence intervals for the inflammatory agents and oxidative stress in the intervention group (apigenin 10 mg/kg), compared with that in the control group (ALI), respectively (correlation: 0.476; 95% confidence intervals, 0.391-0.553, p value = .001, z-value= 9.678) and (correlation: 0.415; 95% confidence intervals, 0.313-0.508, p value= .001, z-value= 7.349). CONCLUSION: Apigenin may have potential anti-inflammatory and antioxidant effects in rat models of ALI. However, the efficacy of apigenin as a therapeutic strategy requires further investigation through prospective controlled randomized trials.


Asunto(s)
Lesión Pulmonar Aguda , Asma , Neumonía , Ratas , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Apigenina/farmacología , Apigenina/uso terapéutico , Estudios Prospectivos , Asma/tratamiento farmacológico , Estrés Oxidativo , Neumonía/tratamiento farmacológico , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Lesión Pulmonar Aguda/tratamiento farmacológico , Pulmón , Inflamación/tratamiento farmacológico
17.
Proc Natl Acad Sci U S A ; 118(42)2021 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-34663699

RESUMEN

In vertebrates, action selection often involves higher cognition entailing an evaluative process. However, urgent tasks, such as defensive escape, require an immediate implementation of the directionality of escape trajectory, necessitating local circuits. Here we reveal a specialized spinal circuit for the execution of escape direction in adult zebrafish. A central component of this circuit is a unique class of segmentally repeating cholinergic V2a interneurons expressing the transcription factor Chx10. These interneurons amplify brainstem-initiated escape commands and rapidly deliver the excitation via a feedforward circuit to all fast motor neurons and commissural interneurons to direct the escape maneuver. The information transfer within this circuit relies on fast and reliable axo-axonic synaptic connections, bypassing soma and dendrites. Unilateral ablation of cholinergic V2a interneurons eliminated escape command propagation. Thus, in vertebrates, local spinal circuits can implement directionality of urgent motor actions vital for survival.


Asunto(s)
Conducta Animal , Médula Espinal/fisiología , Animales , Interneuronas/fisiología , Locomoción/fisiología , Natación/fisiología , Pez Cebra/fisiología
18.
J Appl Clin Med Phys ; : e14521, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39259886

RESUMEN

BACKGROUND: Endometrial cancer is one of the most common gynecological malignancies in the world. Vaginal brachytherapy is an important postoperative adjuvant treatment for endometrial cancer. However, a common problem with existing applicators is insufficient dose at the vaginal apex. PURPOSE: This study describes the Hangzhou (HZ) cylinder, a novel 3D printed vaginal intracavity brachytherapy applicator, detailing its characteristics, dose distribution, and clinical applications. METHODS AND MATERIALS: The HZ cylinder is distinguished by its unique structure: a U-shaped channel with a 2 mm diameter, a straight central axis channel of the same diameter, and 10 parallel straight channels. For comparison, standard plans were employed, designed to ensure that a minimum of 95% of the prescribed dose reached 5 mm beneath the mucosal surface. We conducted comparative analyses of mucosal surface doses and doses at a 5 mm depth below the mucosa between the HZ cylinder and a conventional single-channel cylinder across various treatment schemes. Additionally, the study examined dose differences in target volume and organs at risk (OARs) between actual HZ cylinder plans and hypothetical single-channel plans. RESULTS: In the standard plans, mucosal surface doses at the apex of the vagina were 209.32% and 200.61% of the prescribed dose with the HZ and single-channel cylinders, respectively. The doses on the left and right wall mucosal surfaces varied from 149.26% to 178.13% and 142.98% to 180.75% of the prescribed dose, and on the anterior and posterior wall mucosal surfaces varied from 128.87% to 138.50% and 142.98% to 180.75% of the prescribed dose. Analysis of 24 actual treatment plans revealed that when the vaginal tissue volume dose covering 98% (vaginal D98%) was comparable between the HZ cylinder and virtual single-channel plans (6.74 ± 0.07 Gy vs. 6.69 ± 0.10 Gy, p = 0.24), rectum doses of HZ cylinder plans were significantly lower than those of single-channel plans (D1cc, 5.96 ± 0.56 Gy vs. 6.26 ± 0.71 Gy, p = 0.02 and D2cc, 5.26 ± 0.52 Gy vs. 5.56 ± 0.62 Gy, p = 0.02). CONCLUSIONS: The HZ cylinder demonstrates a reduction in dose to the rectum and bladder while maintaining adequate target volume coverage. Its mucosal surface dose is comparable to that of the traditional single-channel cylinder. These findings suggest that the HZ cylinder is a viable and potentially safer alternative for vaginal brachytherapy, warranting further investigation with larger sample sizes.

19.
Toxicol Ind Health ; 40(4): 156-166, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38284240

RESUMEN

Phthalates (PAEs), a group of environmental endocrine disruptors, are associated with oxidative stress and have adverse effects on female ovarian reserves. However, this association has been poorly investigated, particularly with respect to clinical evidence. In this study, we provided clinical evidence of a relationship between exposure levels of PAEs, oxidative stress and decreased ovarian reserve (DOR). Firstly, the urinary concentrations of metabolites of PAEs were measured by high performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). The serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and anti-Mullerian hormone (AMH), and the biomarkers of oxidative stress, malondialdehyde (MDA), superoxide dismutase (SOD), and total antioxidant capacity (T-AOC), were determined. Finally, statistical analyses were conducted to describe the relationship between the PAEs exposure, oxidative stress and DOR. We found that the levels of monomethyl phthalate (MMP), monoisobutyl phthalate (MiBP), mono-(2-ethylhexyl) phthalate (MEHP), and mono-(2-ethyl-5-hydroxypentyl) phthalate (MECPP) in the DOR group were significantly higher than those in the control group. There was a significant negative association between AMH and MMP, MiBP levels. and a significant positive association between FSH and MMP levels. PAEs exposure was also associated with a significant increase in MDA levels and decrease in SOD levels. In conclusion, the exposure of PAEs was closely associated with DOR, potentially mediated by oxidative stress pathways; however, small sample size was a limitation in this study.


Asunto(s)
Exposición a Riesgos Ambientales , Reserva Ovárica , Ácidos Ftálicos , Humanos , Femenino , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Espectrometría de Masas en Tándem , Estrés Oxidativo , Hormona Folículo Estimulante , Superóxido Dismutasa
20.
J Environ Manage ; 356: 120701, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38531134

RESUMEN

In the context of the "United Nations Decade on Ecosystem Restoration", optimizing spatiotemporal arrangements for ecological restoration is an important approach to enhancing overall socioecological benefits for sustainable development. However, against the background of ecological degradation caused by the human use of most natural resources at levels that have approached or exceeded the safe and sustainable boundaries of ecosystems, it is key to explain how to optimize ecological restoration by classified management and optimal total benefits. In response to these issues, we combined spatial heterogeneity and temporal dynamics at the national scale in China to construct five ecological performance regimes defined by indicators that use planetary boundaries and ecological pressures which served as the basis for prioritizing ecological restoration areas and implementing zoning control. By integrating habitat conservation, biodiversity, water supply, and restoration cost constraints, seven ecological restoration scenarios were simulated to optimize the spatial layout of ecological restoration projects (ERPs). The results indicated that the provinces with unsustainable freshwater use, climate change, and land use accounted for more than 25%, 66.7%, and 25%, respectively, of the total area. Only 30% of the provinces experienced a decrease in environmental pressure. Based on the ecological performance regimes, ERP sites spanning the past 20 years were identified, and more than 50% of the priority areas were clustered in regime areas with increased ecological stress. As the restoration area targets doubled (40%) from the baseline (20%), a multi-objective scenario presents a trade-off between expanded ERPs in areas with highly beneficial effects and minimal restoration costs. In conclusion, a reasonable classification and management regime is the basis for targeted restoration. Coordinating multiple objectives and costs in ecological restoration is the key to maximizing socio-ecological benefits. Our study offered new perspectives on systematic and sustainable planning for ecological restoration.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Humanos , Biodiversidad , China , Abastecimiento de Agua
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