Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 165
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Mol Cell ; 80(4): 607-620.e12, 2020 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-33113344

RESUMEN

Aberrant mitophagy has been implicated in a broad spectrum of disorders. PINK1, Parkin, and ubiquitin have pivotal roles in priming mitophagy. However, the entire regulatory landscape and the precise control mechanisms of mitophagy remain to be elucidated. Here, we uncover fundamental mitophagy regulation involving PINK1 and a non-canonical role of the mitochondrial Tu translation elongation factor (TUFm). The mitochondrion-cytosol dual-localized TUFm interacts with PINK1 biochemically and genetically, which is an evolutionarily conserved Parkin-independent route toward mitophagy. A PINK1-dependent TUFm phosphoswitch at Ser222 determines conversion from activating to suppressing mitophagy. PINK1 modulates differential translocation of TUFm because p-S222-TUFm is restricted predominantly to the cytosol, where it inhibits mitophagy by impeding Atg5-Atg12 formation. The self-antagonizing feature of PINK1/TUFm is critical for the robustness of mitophagy regulation, achieved by the unique kinetic parameters of p-S222-TUFm, p-S65-ubiquitin, and their common kinase PINK1. Our findings provide new mechanistic insights into mitophagy and mitophagy-associated disorders.


Asunto(s)
Drosophila melanogaster/crecimiento & desarrollo , Mitocondrias/patología , Proteínas Mitocondriales/metabolismo , Mitofagia , Factor Tu de Elongación Peptídica/metabolismo , Proteínas Quinasas/metabolismo , Animales , Citosol/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Femenino , Células HeLa , Humanos , Masculino , Mitocondrias/genética , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Factor Tu de Elongación Peptídica/genética , Fosforilación , Dominios y Motivos de Interacción de Proteínas , Proteínas Quinasas/genética , Transporte de Proteínas , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
2.
PLoS Biol ; 21(11): e3002379, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37944100

RESUMEN

[This corrects the article DOI: 10.1371/journal.pbio.3000324.].

3.
Anal Chem ; 96(15): 5852-5859, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38556977

RESUMEN

A multicolor electrochemiluminescence (ECL) biosensor based on a closed bipolar electrode (BPE) array was proposed for the rapid and intuitive analysis of three prostate cancer staging indicators. First, [Irpic-OMe], [Ir(ppy)2(acac)], and [Ru(bpy)3]2+ were applied as blue, green, and red ECL emitters, respectively, whose mixed ECL emission colors covered the whole visible region by varying the applied voltages. Afterward, we designed a simple Mg2+-dependent DNAzyme (MNAzyme)-driven tripedal DNA walker (TD walker) to release three output DNAs. Immediately after, three output DNAs were added to the cathodic reservoirs of the BPE for incubation. After that, we found that the emission colors from the anode of the BPE changed as a driving voltage of 8.0 V was applied, mainly due to changes in the interfacial potential and faradaic currents at the two poles of the BPE. Via optimization of the experimental parameters, cutoff values of such three indicators at different clinical stages could be identified instantly with the naked eye, and standard precision swatches with multiple indicators could be prepared. Finally, in order to precisely determine the prostate cancer stage, the multicolor ECL device was used for clinical analysis, and the resulting images were then compared with standard swatches, laying the way for accurate prostate cancer therapy.


Asunto(s)
Técnicas Biosensibles , Neoplasias de la Próstata , Masculino , Humanos , Mediciones Luminiscentes/métodos , Fotometría , Neoplasias de la Próstata/diagnóstico , Antígeno Prostático Específico , ADN , Técnicas Biosensibles/métodos , Electrodos , Técnicas Electroquímicas/métodos
4.
Small ; : e2401756, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38686699

RESUMEN

Fabrication of nanozyme with catecholase-like catalytic activity faces the great challenge of merging outstanding activity with low cost as well as simple, rapid, and low-energy-consumed production, restricting its industrial applications. Herein, an inexpensive yet robust nanozyme (i.e., DT-Cu) via simple one-step coordination between diaminotriazole (DT) and CuSO4 within 1 h in water at room temperature is constructed. The asymmetric dicopper site with CuN3O configuration for each copper as well as Cu─O bond length of ≈1.83 Å and Cu···Cu distance of ≈3.5 Å in DT-Cu resemble those in catechol oxidase (CO), which ensure its prominent intrinsic activity, outperforming most CO-mimicking nanozymes and artificial homogeneous catalysts. The use of inexpensive DT/CuSO4 in this one-pot strategy endows DT-Cu with only ≈20% cost of natural CO per activity unit. During catalysis, O2 experienced a 4e-dominated reduction process accompanied by the formation of 1O2 and H2O2 intermediates and the product of H2O. Benefiting from the low cost as well as the distinctive structure and superior intrinsic activity, DT-Cu presents potential applications ranging from biocatalysis to analytical detection of biomolecules such as epinephrine and beyond.

5.
Planta ; 259(2): 45, 2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38281265

RESUMEN

MAIN CONCLUSION: The divergence of subsect. Gerardianae was likely triggered by the uplift of the Qinghai-Tibetan Plateau and adjacent mountains. Pinus bungeana might have probably experienced expansion since Last Interglacial period. Historical geological and climatic oscillations have profoundly affected patterns of nucleotide variability, evolutionary history, and species divergence in numerous plants of the Northern Hemisphere. However, how long-lived conifers responded to geological and climatic fluctuations in East Asia remain poorly understood. Here, based on paternally inherited chloroplast genomes and maternally inherited mitochondrial DNA markers, we investigated the population demographic history and molecular evolution of subsect. Gerardianae (only including three species, Pinus bungeana, P. gerardiana, and P. squamata) of Pinus. A low level of nucleotide diversity was found in P. bungeana (π was 0.00016 in chloroplast DNA sequences, and 0.00304 in mitochondrial DNAs). The haplotype-based phylogenetic topology and unimodal distributions of demographic analysis suggested that P. bungeana probably originated in the southern Qinling Mountains and experienced rapid population expansion since Last Interglacial period. Phylogenetic analysis revealed that P. gerardiana and P. squamata had closer genetic relationship. The species divergence of subsect. Gerardianae occurred about 27.18 million years ago (Mya) during the middle to late Oligocene, which was significantly associated with the uplift of the Qinghai-Tibetan Plateau and adjacent mountains from the Eocene to the mid-Pliocene. The molecular evolutionary analysis showed that two chloroplast genes (psaI and ycf1) were under positive selection, the genetic lineages of P. bungeana exhibited higher transition and nonsynonymous mutations, which were involved with the strongly environmental adaptation. These findings shed light on the population evolutionary history of white pine species and provide striking insights for comprehension of their species divergence and molecular evolution.


Asunto(s)
Genoma del Cloroplasto , Pinus , Filogenia , Pinus/genética , Genoma del Cloroplasto/genética , Evolución Molecular , ADN de Cloroplastos/genética , ADN Mitocondrial/genética , Nucleótidos , Demografía , Variación Genética
6.
J Cardiovasc Electrophysiol ; 35(7): 1440-1449, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38757370

RESUMEN

INTRODUCTION: The accuracy of surface ECG algorithms for predicting the origin of outflow tract ventricular arrhythmias (OT-VAs) might be questioned. Intracardiac electrograms recorded at anatomic landmarks could provide new predictive insights. We aim to evaluate the efficacy of a novel criterion utilizing the activation pattern of the coronary sinus (CS) in localizing OT-VAs, including VAs originating from the right ventricular outflow tract (RVOT), endocardial left ventricular outflow tract (Endo-LVOT), and epicardial left ventricular outflow tract (Epi-LVOT). METHODS: We measured the ventricular activation time of the mitral annulus (MA) from the onset of the earliest QRS complex of VAs to the initial deflection over the isoelectric line at local signals, namely the QRS-MA interval. The activation at 3 and 12 o'clock of the MA was recorded as the QRS-MA3 and QRS-MA12 intervals, respectively. Their predictive values were compared to previous ECG algorithms. RESULTS: A total of 68 patients with OT-VAs were enrolled (51 for development and 17 for validation). From early to late, the ventricular activation sequences at MA12 were as follows: Epi-LVOT, Endo-LVOT, and RVOT. In LBBB morphology OT-VAs, the QRS-MA12 interval was significantly earlier for LVOT origins than RVOT origins. In the combined cohort of development and validation cohort, a cut-off value of ≤10 ms predicted the LVOT origin with a sensitivity of 100% and specificity of 78%. The QRS-MA12 interval ≤ -24 ms additionally predicted epicardial LVOT sites of origin. CONCLUSIONS: The QRS-MA interval could accurately differentiate the OT-VAs localization.


Asunto(s)
Potenciales de Acción , Seno Coronario , Electrocardiografía , Frecuencia Cardíaca , Valor Predictivo de las Pruebas , Humanos , Seno Coronario/fisiopatología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Algoritmos , Técnicas Electrofisiológicas Cardíacas , Reproducibilidad de los Resultados , Factores de Tiempo , Taquicardia Ventricular/fisiopatología , Taquicardia Ventricular/diagnóstico , Arritmias Cardíacas/fisiopatología , Arritmias Cardíacas/diagnóstico , Adulto , Diagnóstico Diferencial
7.
Langmuir ; 40(3): 1892-1901, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38192235

RESUMEN

Polyelectrolyte complexes (PECs) have emerged as an attractive category of materials for their water processability and some similarities to natural biopolymers. Herein, we employ the intrinsic hydroplasticity of PEC materials to enable the generation of porous structures with the aid of gas foaming. Such foamable materials are fabricated by simply mixing polycation, polyanion, and a UV-initiated chemical foaming agent in an aqueous solution, followed by molding into thin films. The gas foaming of the PEC films can be achieved upon exposure to UV illumination under water, where the films are plasticized and the gaseous products from the photolysis of foaming agents afford the formation, expanding, and merging of numerous bubbles. The porosity and morphology of the resulting porous films can be customized by tuning film composition, foaming conditions, and especially the degree of plasticizing effect, illustrating the high flexibility of this hydroplastic foaming method. Due to the rapid initiation of gas foaming, the present method enables the formation of porous structures via an instant one-step process, much more efficient than those existing strategies for porous PEC materials. More importantly, such a pore-forming mechanism might be extended to other hydroplastic materials (e.g., biopolymers) and help to yield hydroplasticity-based processing strategies.

8.
Planta Med ; 90(5): 353-367, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38295847

RESUMEN

Gambogenic acid is a derivative of gambogic acid, a polyprenylated xanthone isolated from Garcinia hanburyi. Compared with the more widely studied gambogic acid, gambogenic acid has demonstrated advantages such as a more potent antitumor effect and less systemic toxicity than gambogic acid according to early investigations. Therefore, the present review summarizes the effectiveness and mechanisms of gambogenic acid in different cancers and highlights the mechanisms of action. In addition, drug delivery systems to improve the bioavailability of gambogenic acid and its pharmacokinetic profile are included. Gambogenic acid has been applied to treat a wide range of cancers, such as lung, liver, colorectal, breast, gastric, bladder, and prostate cancers. Gambogenic acid exerts its antitumor effects as a novel class of enhancer of zeste homolog 2 inhibitors. It prevents cancer cell proliferation by inducing apoptosis, ferroptosis, and necroptosis and controlling the cell cycle as well as autophagy. Gambogenic acid also hinders tumor cell invasion and metastasis by downregulating metastasis-related proteins. Moreover, gambogenic acid increases the sensitivity of cancer cells to chemotherapy and has shown effects on multidrug resistance in malignancy. This review adds insights for the prevention and treatment of cancers using gambogenic acid.


Asunto(s)
Antineoplásicos , Xantenos , Animales , Apoptosis , Línea Celular Tumoral , Xantenos/farmacología , Xantenos/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico
9.
Dis Esophagus ; 37(4)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38189470

RESUMEN

Herein, we aimed to evaluate the efficacy and safety of camrelizumab combined with docetaxel and carboplatin as a neoadjuvant treatment for locally advanced oesophageal squamous cell carcinoma (OSCC). Fifty-one patients with OSCC, treated from July 2020 to October 2022, were analyzed. Of them, 41 patients underwent surgery 4-8 weeks after undergoing two cycles of camrelizumab (200 mg IV Q3W) combined with docetaxel (75 mg/m2 IV Q3W) and carboplatin (area under the curve = 5-6 IV Q3W). The primary endpoint was the pathological complete response rate. All 51 patients (100%) experienced treatment-related grades 1-2 adverse events, and 2 patients (3.9%) experienced grade 4 events (including elevated alanine transaminase/aspartate transferase levels and Guillain-Barre syndrome). Fifty patients were evaluated for the treatment efficacy. Of them, 13 achieved complete response, and the objective response rate was 74%. Only 41 patients underwent surgical treatment. The pathological complete response rate was 17.1%, the major pathological response rate was 63.4%, and the R0 resection rate was 100%. Approximately 22% of the patients had tumor regression grades 0. Eight patients (19.5%) developed surgery-related complications. The median follow-up time was 18 months (range: 3-29 months). Four patients experienced disease progression, while four died. The median disease-free survival and overall survival were not reached. Camrelizumab combined with docetaxel and carboplatin is an effective and safe neoadjuvant treatment for locally advanced OSCC. This regimen may afford a potential strategy to treat patients with locally advanced OSCC.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Docetaxel/uso terapéutico , Carboplatino , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/patología , Terapia Neoadyuvante , Estadificación de Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Esofágicas/patología
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(4): 432-436, 2024 Apr 15.
Artículo en Zh | MEDLINE | ID: mdl-38660910

RESUMEN

The patient, a male newborn, was admitted to the hospital 2 hours after birth due to prematurity (gestational age 27+5 weeks) and respiratory distress occurring 2 hours postnatally. After admission, the infant developed fever and elevated C-reactive protein levels. On the fourth day after birth, metagenomic next-generation sequencing of cerebrospinal fluid indicated a positive result for Mycoplasma hominis (9 898 reads). On the eighth day, a retest of cerebrospinal fluid metagenomics confirmed Mycoplasma hominis (56 806 reads). The diagnosis of purulent meningitis caused by Mycoplasma hominis was established, and the antibiotic treatment was switched to moxifloxacin [5 mg/(kg·day)] administered intravenously for a total of 4 weeks. After treatment, the patient's cerebrospinal fluid tests returned to normal, and he was discharged as cured on the 76th day after birth. This article focuses on the diagnosis and treatment of neonatal Mycoplasma hominis purulent meningitis, introducing the multidisciplinary diagnosis and treatment of the condition in extremely preterm infants.


Asunto(s)
Recien Nacido Extremadamente Prematuro , Moxifloxacino , Mycoplasma hominis , Humanos , Mycoplasma hominis/aislamiento & purificación , Recién Nacido , Masculino , Moxifloxacino/uso terapéutico , Moxifloxacino/administración & dosificación , Meningitis Bacterianas/tratamiento farmacológico , Meningitis Bacterianas/microbiología , Meningitis Bacterianas/diagnóstico , Infecciones por Mycoplasma/tratamiento farmacológico , Infecciones por Mycoplasma/diagnóstico , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación
11.
Mol Phylogenet Evol ; 182: 107736, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36805473

RESUMEN

Hybridization is recognized as a major force in species evolution and biodiversity formation, generally leading to the origin and differentiation of new species. Multiple hybridization events cannot easily be reconstructed, yet they offer the potential to study a number of evolutionary processes. Here, we used nuclear expressed sequence tag-simple sequence repeat and large-scale single nucleotide polymorphism variation data, combined with niche analysis, to investigate the putative independent hybridization events in Notopterygium, a group of perennial herb plants endemic to China. Population genomic analysis indicated that the four studied species are genetically well-delimited and that N. forrestii and N. oviforme have originated by hybridization. According to Approximate Bayesian Computation, the best-fit model involved the formation of N. forrestii from the crossing of N. franchetii and N. incisum, with N. forrestii further backcrossing to N. franchetii to form N. oviforme. The niche analyses indicated that niche divergence [likely triggered by the regional climate changes, particularly the intensification of East Asian winter monsoon, and tectonic movements (affecting both Qinghai-Tibetan Plateau and Qinling Mountains)] may have promoted and maintained the reproductive isolation among hybrid species. N. forrestii shows ecological specialization with respect to their parental species, whereas N. oviforme has completely shifted its niche. These results suggested that the climate and environmental factors together triggered the two-step hybridization of the East Asia herb plants. Our study also emphasizes the power of genome-wide SNPs for investigating suspected cases of hybridization, particularly unravelling old hybridization events.


Asunto(s)
Apiaceae , Hibridación Genética , Apiaceae/genética , Teorema de Bayes , Ecosistema , Metagenómica , Filogenia
12.
BMC Cardiovasc Disord ; 23(1): 516, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37875809

RESUMEN

BACKGROUND: The vein of Marshall (VOM) ethanol infusion is increasingly performed in combination with catheter ablation in atrial fibrillation (AF). The cannulation of the VOM can sometimes be challenging. This study aimed to evaluate the double-wire technique in cases of difficult cannulation of the VOM. CASE PRESENTATION: Patients with AF scheduled for combined catheter ablation and VOM ethanol infusion were consecutively enrolled. The procedure was performed via the femoral vein. If the regular cannulation technique with one angioplasty wire failed or took more than 20 min, the double-wire technique using a stabilizing wire and a cannulation wire was performed. The unique technique was used mainly in two scenarios, when the Eustachian ridge was too prominent as a barrier for catheter manipulation or when the VOM ostium was close to the coronary sinus ostium. Of 162 patients scheduled for VOM ethanol infusion, the double-wire technique was applied in 6 (3.7%) patients and led to a 100% successful cannulation rate of the VOM. Of the six patients, two had a prominent Eustachian ridge, and four had a VOM ostium close to the coronary sinus ostium. The mean cannulation time was 33.3 ± 7.3 min. The ethanol infusion was successfully performed in 5 patients. One patient had a collateral circulation in the distal VOM, and ethanol infusion was not performed. CONCLUSIONS: The double-wire technique can facilitate VOM cannulation and ethanol infusion in challenging cases. WORD COUNT: 231.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Seno Coronario , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/terapia , Ablación por Catéter/métodos , Cateterismo , Seno Coronario/cirugía , Vasos Coronarios , Etanol/administración & dosificación
13.
PLoS Biol ; 17(6): e3000324, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31226106

RESUMEN

The molecular mechanism controlling the zygotic genome activation (ZGA) in mammals remains poorly understood. The 2-cell (2C)-like cells spontaneously emerging from cultures of mouse embryonic stem cells (ESCs) share some key transcriptional and epigenetic programs with 2C-stage embryos. By studying the transition of ESCs into 2C-like cells, we identified developmental pluripotency associated 2 and 4 (Dppa2/4) as important regulators controlling zygotic transcriptional program through directly up-regulating the expression of double homeobox (Dux). In addition, we found that DPPA2 protein is sumoylated and its activity is negatively regulated by small ubiquitin-like modifier (Sumo) E3 ligase protein inhibitor of activated STAT 4 (PIAS4). PIAS4 is down-regulated during ZGA process and during transitioning of ESCs into 2C-like cells. Depleting Pias4 or overexpressing Dppa2/4 is sufficient to activate 2C-like transcriptional program, whereas depleting Dppa2/4 or forced expression of Pias4 or Sumo2-Dppa2 inhibits 2C-like transcriptional program. Furthermore, ectopic expression of Pias4 or Sumo2-Dppa2 impairs early mouse embryo development. In summary, our study identifies key molecular rivals consisting of transcription factors and a Sumo2 E3 ligase that regulate zygotic transcriptional program upstream of Dux.


Asunto(s)
Proteínas Nucleares/metabolismo , Proteínas Inhibidoras de STAT Activados/metabolismo , Factores de Transcripción/metabolismo , Animales , Línea Celular , Proteínas de Unión al ADN/metabolismo , Desarrollo Embrionario/genética , Células Madre Embrionarias/metabolismo , Femenino , Genoma , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Nucleares/fisiología , Proteínas de Unión a Poli-ADP-Ribosa , Proteínas Inhibidoras de STAT Activados/fisiología , Proteína SUMO-1/metabolismo , Proteína SUMO-1/fisiología , Análisis de la Célula Individual , Sumoilación , Factores de Transcripción/fisiología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/fisiología , Cigoto/metabolismo
14.
Genomics ; 113(4): 2365-2376, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34051325

RESUMEN

The forest tree family Aceraceae is widespread in the northern hemisphere and it has ecological and economic importance. However, the phylogenetic relationships and classifications within the family are still controversial due to transitional intraspecific morphological characteristics and introgression hybridization among species. In this study, we determined the evolutionary relationships and molecular evolution of Aceraceae based on plastid phylogenomics and two nuclear gene variations. Phylogenetic analysis based on the plastid genomes suggested that Aceraceae species can be divided into two larger sub-clades corresponding to the two genera Acer and Dipteronia. Conjoint analysis of the plastid and nuclear gene sequences supported the classification with two genera in the family. Molecular dating showed that the two genera diverged 60.2 million years ago, which is generally consistently with previously reported results. Divergence hotspots and positively selected genes identified in the plastid genomes could be useful genetic resources in Aceraceae.


Asunto(s)
Aceraceae , Evolución Molecular , Bosques , Filogenia , Plastidios/genética
15.
Anal Chem ; 91(12): 7902-7910, 2019 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-31135138

RESUMEN

This work reports an electrofluorochromic strategy on the basis of electric field control of fluorescent signal generation on bipolar electrodes (BPEs) for visualizing cancer cell surface glycoprotein (mucin 1). The device included two separate cells: anodic sensing cell and cathodic reporting cell, which were connected by a screen-printing electrode patterned on poly(ethylene terephthalate) (PET) membrane. In the sensing cell, anti-MUC1 antibody immobilized on a chitosan-multiwalled carbon nanotube (CS-MWCNT)-modified anodic BPE channel was used for capturing mucin-1 (MUC1) or MCF-7 cancer cells. Then ferrocene (Fc)-labeled mucin 1 aptamers were introduced through hybridization. Under an applied voltage, the ferrocene was oxidized and the electroactive molecules of 1,4-benzoquinone (BQ) in the cathodic reporting cell were reduced according to electroneutrality. This produced a strongly basic 1,4-benzoquinone anion radical (BQ•-), which turned on the fluorescence of pH-responsive fluorescent molecules of (2-(2-(4-hydroxystyryl)-6-methyl-4 H-pyran-4-ylidene)malononitrile) (SPM) coexisting in the cathode reporting cell for both spectrophotometric detection and imaging. This strategy allowed sensitive detection of MUC1 at a concentration down to 10 fM and was capable of detecting a minimum of three MCF-7 cells. Furthermore, the amount of MUC1 on MCF-7 cells was calculated to be 6.02 × 104 molecules/cell. Our strategy also had the advantages of high temporal and spatial resolution, short response time, and high luminous contrast and is of great significance for human health and the promotion of life science development.


Asunto(s)
Técnicas Biosensibles/instrumentación , Mucina-1/análisis , Aptámeros de Nucleótidos/genética , Aptámeros de Nucleótidos/metabolismo , Secuencia de Bases , Electroquímica , Electrodos , Humanos , Células MCF-7 , Mucina-1/metabolismo , Oxidación-Reducción , Espectrometría de Fluorescencia
16.
Anal Chem ; 91(24): 15804-15810, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-31718146

RESUMEN

Because of the extremely low solubility of gas pollution, elucidating the pathogenetic mechanism between air pollution and the lung inflammatory response has remained a significant challenge. Here, we develop a bioinspired nanoporous membrane (BNM) with a three-phase interface as a gas exposure model that mimicks the airway mechanism, gas molecules contacting with alveolar cells directly, enabling high cell viability and sensitive inflammatory response analysis. Specifically, the top side of the porous anodic alumina (PAA) membrane was in contact with the medium for cell culture, and the bottom side contacted the gas phase directly for gas exposure. Compared with the two-phase interface, the viability of cells on the BNM was enhanced up to 3-fold. Additionally, results demonstrated that the inflammatory responses of cells stimulated by gas pollution (formaldehyde and benzene as models) from the gas phase were more obvious than those induced by gas pollution from solution, especially the increment of interleukin-2 (IL-2), IL-6, and tumor necrosis factor α (TNF-α), which was almost 2 times greater than that induced by gas pollution from solution. Furthermore, an enzyme inhibitor was introduced to evaluate potential applications of the BNM.


Asunto(s)
Membranas Artificiales , Modelos Biológicos , Nanoporos , Óxido de Aluminio/química , Benceno/toxicidad , Técnicas de Cultivo de Célula , Línea Celular , Supervivencia Celular/efectos de los fármacos , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Formaldehído/toxicidad , Gases/química , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Inflamación/metabolismo , Inflamación/patología , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
17.
Heredity (Edinb) ; 123(2): 242-263, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30742051

RESUMEN

Historical geological and climatic events are the most important drivers of population expansions/contractions, range shifts, and interspecific divergence in plants. However, the species divergence and spatiotemporal population dynamics of alpine cold-tolerant herbal plants in the high-altitude Qinghai-Tibetan Plateau (QTP) and adjacent areas remain poorly understood. In this study, we investigated population evolutionary history of four endangered Notopterygium herb species in the QTP and adjacent regions. We sequenced 10 nuclear loci, 2 mitochondrial DNA regions, and 4 chloroplast DNA regions in a total of 72 natural populations from the 4 species, and tested the hypothesis that the population history of these alpine herbs was markedly affected by the Miocene-Pliocene QTP uplifts and Quaternary climatic oscillations. We found that the four Notopterygium species had generally low levels of nucleotide variability within populations. Molecular dating and isolation-with-migration analyses suggested that Notopterygium species diverged ~1.74-7.82 million years ago and their differentiation was significantly associated with recent uplifts of the eastern margin of the QTP. In addition, ecological niche modeling and population history analysis showed that N. incisum and N. franchetii underwent considerable demographic expansions during the last glacial period of the Pleistocene, whereas a demographic contraction and a expansion occurred for N. forrestii and N. oviforme during the antepenultimate interglacial period and penultimate glacial period, respectively. These findings highlight the importance of geological and climatic changes during the Miocene-Pliocene and Pleistocene as causes of species divergence and changes in population structure within cold-tolerant herbs in the QTP biodiversity hotspot.


Asunto(s)
Plantas Medicinales/genética , Plantas/genética , Biodiversidad , Evolución Biológica , ADN de Cloroplastos/genética , ADN Mitocondrial/genética , ADN de Plantas/genética , Ecosistema , Variación Genética/genética , Especificidad de la Especie , Tibet
19.
Angew Chem Int Ed Engl ; 58(36): 12481-12485, 2019 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-31317609

RESUMEN

A biomimetic conical submicrochannel (tip side ca. 400 nm) with functions of continuously tunable ion rectification and conductance based on thermoresponsive polymer layer-by-layer (LbL) self-assembly is presented. These self-assembled polymers with different layers exhibited a capability to regulate the effective channel diameter, and different ion rectifications/conductance were achieved. By controlling temperature, the conformation and wettability of the assembled polymers were reversibly transformed, thus the ion rectification/conductance could be further adjusted subtly. Owing to the synergistic effect, the ion conductance could be tuned over a wide range spanning three orders of magnitude. Moreover, the proposed system can be applied for on-demand on-off molecule delivery, which was important for disease therapy. This study opens a new door for regulating channel size according to actual demand and sensing big targets with different size with one channel.

20.
Proc Natl Acad Sci U S A ; 112(12): 3710-5, 2015 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-25751889

RESUMEN

Bone morphogenetic proteins (BMPs) belong to the TGF-ß family, whose 33 members regulate multiple aspects of morphogenesis. TGF-ß family members are secreted as procomplexes containing a small growth factor dimer associated with two larger prodomains. As isolated procomplexes, some members are latent, whereas most are active; what determines these differences is unknown. Here, studies on pro-BMP structures and binding to receptors lead to insights into mechanisms that regulate latency in the TGF-ß family and into the functions of their highly divergent prodomains. The observed open-armed, nonlatent conformation of pro-BMP9 and pro-BMP7 contrasts with the cross-armed, latent conformation of pro-TGF-ß1. Despite markedly different arm orientations in pro-BMP and pro-TGF-ß, the arm domain of the prodomain can similarly associate with the growth factor, whereas prodomain elements N- and C-terminal to the arm associate differently with the growth factor and may compete with one another to regulate latency and stepwise displacement by type I and II receptors. Sequence conservation suggests that pro-BMP9 can adopt both cross-armed and open-armed conformations. We propose that interactors in the matrix stabilize a cross-armed pro-BMP conformation and regulate transition between cross-armed, latent and open-armed, nonlatent pro-BMP conformations.


Asunto(s)
Proteína Morfogenética Ósea 7/química , Factores de Diferenciación de Crecimiento/química , Factor de Crecimiento Transformador beta/química , Secuencia de Aminoácidos , Animales , Células CHO , Cricetinae , Cricetulus , Factor 2 de Diferenciación de Crecimiento , Células HEK293 , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Datos de Secuencia Molecular , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Homología de Secuencia de Aminoácido , Transducción de Señal
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA