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1.
Nat Immunol ; 16(12): 1282-91, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26502406

RESUMEN

To elucidate the transcriptional 'landscape' that regulates human lymphoid commitment during postnatal life, we used RNA sequencing to assemble the long non-coding transcriptome across human bone marrow and thymic progenitor cells spanning the earliest stages of B lymphoid and T lymphoid specification. Over 3,000 genes encoding previously unknown long non-coding RNAs (lncRNAs) were revealed through the analysis of these rare populations. Lymphoid commitment was characterized by lncRNA expression patterns that were highly stage specific and were more lineage specific than those of protein-coding genes. Protein-coding genes co-expressed with neighboring lncRNA genes showed enrichment for ontologies related to lymphoid differentiation. The exquisite cell-type specificity of global lncRNA expression patterns independently revealed new developmental relationships among the earliest progenitor cells in the human bone marrow and thymus.


Asunto(s)
Linfocitos B/metabolismo , Linaje de la Célula/genética , Células Progenitoras Linfoides/metabolismo , ARN Largo no Codificante/genética , Linfocitos T/metabolismo , Transcriptoma , Teorema de Bayes , Células de la Médula Ósea/metabolismo , Análisis por Conglomerados , Perfilación de la Expresión Génica/métodos , Ontología de Genes , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ARN/métodos , Timo/citología , Timo/metabolismo
2.
Nat Immunol ; 13(10): 963-71, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22941246

RESUMEN

Expression of the cell-surface antigen CD10 has long been used to define the lymphoid commitment of human cells. Here we report a unique lymphoid-primed population in human bone marrow that was generated from hematopoietic stem cells (HSCs) before onset of the expression of CD10 and commitment to the B cell lineage. We identified this subset by high expression of the homing molecule L-selectin (CD62L). CD10(-)CD62L(hi) progenitors had full lymphoid and monocytic potential but lacked erythroid potential. Gene-expression profiling placed the CD10(-)CD62L(hi) population at an intermediate stage of differentiation between HSCs and lineage-negative (Lin(-)) CD34(+)CD10(+) progenitors. CD62L was expressed on immature thymocytes, and its ligands were expressed at the cortico-medullary junction of the thymus, which suggested a possible role for this molecule in homing to the thymus. Our studies identify the earliest stage of lymphoid priming in human bone marrow.


Asunto(s)
Células de la Médula Ósea/inmunología , Células Madre Hematopoyéticas/metabolismo , Selectina L/biosíntesis , Neprilisina/biosíntesis , Antígenos CD34/inmunología , Antígenos CD34/metabolismo , Antígenos CD7/inmunología , Células de la Médula Ósea/metabolismo , Diferenciación Celular , Linaje de la Célula , Células Cultivadas , Perfilación de la Expresión Génica , Células Madre Hematopoyéticas/inmunología , Humanos , Timocitos/inmunología , Timocitos/metabolismo , Timo/metabolismo , Regulación hacia Arriba
3.
Eur J Nucl Med Mol Imaging ; 51(5): 1423-1435, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38110710

RESUMEN

PURPOSE: Determination of isocitrate dehydrogenase (IDH) genotype is crucial in the stratification of diagnosis and prognostication in diffuse gliomas. We sought to build and validate radiomics models and clinical features incorporated nomogram for preoperative prediction of IDH mutation status and WHO grade of diffuse gliomas with L-[methyl-11C] methionine ([11C]MET) PET/CT imaging according to the 2016 WHO classification of tumors of the central nervous system. METHODS: Consecutive 178 preoperative [11C]MET PET/CT images were retrospectively studied for radiomics analysis. One hundred six patients from PET scanner 1 were used as training dataset, and 72 patients from PET scanner 2 were used for validation dataset. [11C]MET PET and integrated CT radiomics features were extracted, respectively; three independent predictive models were built based on PET features, CT features, and combined PET/CT features, respectively. The SelectKBest method, Spearman correlation analysis, Least Absolute Shrinkage and Selection Operator (LASSO) regression, and machine learning algorithms were applied for feature selection and model building. After filtering the satisfactory predictive model, key clinical features were incorporated for the nomogram establishment. RESULTS: The combined [11C]MET PET/CT radiomics model, which consisted of four PET features and eight integrated CT features, was significantly associated with IDH genotype (p < 0.0001 for both training and validation datasets). Nomogram based on the [11C]MET PET/CT radiomics score, patients' age, and dichotomous tumor location status showed satisfactory discrimination capacity, and the AUC was 0.880 (95% CI, 0.726-0.998) in the training dataset and 0.866 (95% CI, 0.777-0.956) in the validation dataset. In IDH stratified WHO grade prediction, the final radiomics model consists of four PET features and two CT features had reasonable and stable differential efficacy of WHO grade II and III patients from grade IV patients in IDH-wildtype patients, and the AUC was 0.820 (95% CI, 0.541-1.000) in the training dataset and 0.766 (95% CI, 0.612-0.921) in the validation dataset. CONCLUSION: [11C]MET PET radiomics features could benefit non-invasive IDH genotype prediction, and integrated CT radiomics features could enhance the efficacy. Radiomics and clinical features incorporation could establish satisfactory nomogram for clinical application. This non-invasive predictive investigation based on our consecutive cohort from two PET scanners could provide the perspective to observe the differential efficacy and the stability of radiomics-based investigation in untreated diffuse gliomas.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Isocitrato Deshidrogenasa/genética , Estudios de Cohortes , Metionina , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiómica , Radioisótopos de Carbono , Glioma/diagnóstico por imagen , Glioma/genética , Glioma/patología , Racemetionina , Mutación , Organización Mundial de la Salud
4.
Environ Sci Technol ; 58(6): 3041-3053, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38291736

RESUMEN

Typically, SO2 unavoidably deactivates catalysts in most heterogeneous catalytic oxidations. However, for Pt-based catalysts, SO2 exhibits an extraordinary boosting effect in propane catalytic oxidation, but the promotive mechanism remains contentious. In this study, an in situ-formed tactful (Pt-S-O)-Ti structure was concluded to be a key factor for Pt/TiO2 catalysts with a substantial SO2 tolerance ability. The experiments and theoretical calculations confirm that the high degree of hybridization and orbital coupling between Pt 5d and S 3p orbitals enable more charge transfer from Pt to S species, thus forming the (Pt-S-O)-Ti structure with the oxygen atom dissociated from the chemisorbed O2 adsorbed on oxygen vacancies. The active oxygen atom in the (Pt-S-O)-Ti active structure is a robust site for C3H8 adsorption, leading to a better C3H8 combustion performance. This work can provide insights into the rational design of chemical bonds for high SO2 tolerance catalysts, thereby improving economic and environmental benefits.


Asunto(s)
Oxígeno , Titanio , Titanio/química , Oxidación-Reducción , Catálisis , Adsorción
5.
Exp Parasitol ; 259: 108719, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38364954

RESUMEN

BACKGROUND: Rabbit coccidiosis is a parasitism caused by either one or multiple co-infections of Eimeria species. Among them, Eimeria intestinalis is the primary pathogen responsible for diarrhea, growth retardation, and potential mortality in rabbits. Concerns regarding drug resistance and drug residues have led to the development of recombinant subunit vaccines targeting Eimeria species as a promising preventive measure. The aim of this study was to assess the immunoprotective efficacy of recombinant subunit vaccines comprising EiROP25 and EiROP30 (rhoptry proteins (ROPs)) against E. intestinalis infection in rabbits. METHODS: Cloning, prokaryotic expression, and protein purification were performed to obtain EiROP25 and EiROP30. Five groups of fifty 35-day-old Eimeria-free rabbits were created (unchallenged control group, challenged control group, vector protein control group, rEiROP25 group, and rEiROP30 group), with 10 rabbits in each group. Rabbits in the rEiROP25 and rEiROP30 groups were immunized with the recombinant proteins (100 µg per rabbit) for primary and booster immunization (100 µg per rabbit) at a two-week intervals, and challenged with 7 × 104 oocysts per rabbit after an additional two-week interval. Two weeks after the challenge, the rabbits were euthanized for analysis. Weekly collections of rabbit sera were made to measure changes in specific IgG and cytokine level. Clinical symptoms and pathological changes after challenge were observed and recorded. At the conclusion of the animal experiment, lesion scores, the relative weight increase ratio, the oocyst reduction rate, and the anticoccidial index were computed. RESULTS: Rabbits immunized with rEiROP25 and rEiROP30 exhibited relative weight gain ratios of 56.57% and 72.36%, respectively. Oocysts decreased by 78.14% and 84.06% for the rEiROP25 and rEiROP30 groups, respectively. The anticoccidial indexes were 140 and 155. Furthermore, there was a noticeable drop in intestinal lesions. After the primary immunization with rEiROP25 and rEiROP30, a week later, there was a notable rise in specific IgG levels, which remained elevated for two weeks following challenge (P < 0.05). Interleukin (IL)-2 levels increased markedly in the rEiROP25 group, whereas IL-2, interferon gamma (IFN-γ), and IL-4 levels increased substantially in the rEiROP30 group (P < 0.05). CONCLUSION: Immunization of rabbits indicated that both rEiROP25 and rEiROP30 are capable of inducing an increase in specific antibody levels. rEiROP25 triggered a Th1-type immune protection response, while rEiROP30 elicited a Th1/Th2 mixed response. EiROP25 and EiROP30 can generate a moderate level of immune protection, with better efficacy observed for EiROP30. This study provides valuable insights for the promotion of recombinant subunit vaccines targeting rabbit E. intestinalis infection.


Asunto(s)
Coccidiosis , Eimeria , Enfermedades de las Aves de Corral , Vacunas Antiprotozoos , Conejos , Animales , Coccidiosis/prevención & control , Coccidiosis/veterinaria , Proteínas Recombinantes , Vacunas Sintéticas , Oocistos , Vacunas de Subunidad , Inmunoglobulina G , Pollos , Enfermedades de las Aves de Corral/prevención & control
6.
Infect Immun ; 91(11): e0020823, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37823630

RESUMEN

Eimeria intestinalis is the most pathogenic species of rabbit coccidiosis, causing weight loss, diarrhea, and even acute death. The currently used anticoccidial drugs against E. intestinalis in rabbits are associated with drug resistance and residues. Immunological control might be a potential alternative. We cloned and expressed the E. intestinalis recombinant EF1α and EFG (rEi-EF1α and rEi-EFG, respectively). Rabbits were immunized subcutaneously every 14 days with 100 µg of rEi-EF1α and rEi-EFG and followed by 5 × 104 E. intestinalis sporulated oocysts orally challenge. Serum samples were collected every 7 days to measure the levels of specific antibodies and cytokines. On post-challenge day 14, rabbits were sacrificed and the anticoccidial index was evaluated. The rabbits of PBS challenged groups exhibited anorexia, diarrhea, marked intestinal wall thickening, and white nodules that formed patches, while rabbits from the rEi-EF1α or rEi-EFG challenged group exhibited milder symptoms. The rEi-EF1α group showed a 75.18% oocyst reduction and 89.01%wt gain; the rEi-EFG group had a 60.58% oocyst reduction and 56.04%wt gain. After vaccination, specific IgG levels increased and stayed high (P < 0.05). The IL-4 and IL-2 levels of rEi-EF1α immunized groups showed a significant increase after immunization (P < 0.05). Both rEi-EF1α and rEi-EFG could induce humoral and cellular immune responses. In contrast, rabbits immunized with rEi-EF1α were better protected from challenge by E. intestinalis than rEi-EFG.


Asunto(s)
Coccidiosis , Eimeria , Enfermedades de las Aves de Corral , Vacunas Antiprotozoos , Animales , Conejos , Coccidiosis/prevención & control , Inmunización , Vacunación , Diarrea , Oocistos , Pollos , Enfermedades de las Aves de Corral/prevención & control
7.
Eur J Nucl Med Mol Imaging ; 50(5): 1395-1405, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36627498

RESUMEN

PURPOSE: Human post mortem studies have described the topographical patterns of tau pathology in progressive supranuclear palsy (PSP). Recent advances in tau PET tracers are expected to herald the next era of PSP investigation for early detection of tau pathology in living brains. This study aimed to investigate whether 18F-Florzolotau PET imaging may capture the distribution patterns and regional vulnerability of tau pathology in PSP, and to devise a novel image-based staging system. METHODS: The study cohort consisted of 148 consecutive patients with PSP who had undergone 18F-Florzolotau PET imaging. The PSP rating scale (PSPrs) was used to measure disease severity. Similarities and differences of tau deposition among different clinical phenotypes were examined at the regional and voxel levels. An 18F-Florzolotau pathological staging system was devised according to the scheme originally developed for post mortem data. In light of conditional probabilities for the sequence of events, an 18F-Florzolotau modified staging system by integrating clusters at the regional level was further developed. The ability of 18F-Florzolotau staging systems to reflect disease severity in terms of PSPrs score was assessed by analysis of variance. RESULTS: The distribution patterns of 18F-Florzolotau accumulation in living brains of PSP showed a remarkable similarity to those reported in post mortem studies, with the binding intensity being markedly higher in Richardson's syndrome. Moreover, 18F-Florzolotau PET imaging allowed detecting regional vulnerability and tracking tau accumulation in an earlier fashion compared with post mortem immunostaining. The 18F-Florzolotau staging systems were positively correlated with clinical severity as reflected by PSPrs scores. CONCLUSIONS: 18F-Florzolotau PET imaging can effectively capture the distribution patterns and regional vulnerability of tau pathology in PSP. The 18F-Florzolotau modified staging system holds promise for early tracking of tau deposition in living brains.


Asunto(s)
Parálisis Supranuclear Progresiva , Humanos , Encéfalo/metabolismo , Tomografía de Emisión de Positrones/métodos , Parálisis Supranuclear Progresiva/diagnóstico por imagen , Proteínas tau/metabolismo
8.
Int J Mol Sci ; 24(19)2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37833865

RESUMEN

Eimeria intestinalis infects rabbits, causing severe intestinal coccidiosis. Prolonged anticoccidial drug use might lead to coccidia resistance and drug residues in food. Thus, vaccines are required to control rabbit coccidiosis. In this study, recombinant E. intestinalis 14-3-3 and GRA10 proteins (rEi-14-3-3 and rEi-GRA10) were obtained via prokaryotic expression and used as recombinant subunit vaccines. Fifty 30-day-old rabbits were randomly grouped as follows: PBS-uninfected group, PBS-infected group, Trx-His-S control group, and rEi-14-3-3 and rEi-GRA10 immunized groups. The rabbits were subcutaneously immunized twice at 2-week intervals, challenged with 7 × 104 sporulated oocysts, and sacrificed 14 days later. The protective effects were assessed via clinical signs, relative weight gain, oocyst reduction, mean intestinal lesion score, ACI (anticoccidial index), cytokine, and specific antibody levels in sera. The rEi-14-3-3 and rEi-GRA10 groups had higher relative weight gain rates of 81.94% and 73.61% (p < 0.05), and higher oocyst reduction rates of 86.13% and 84.87% (p < 0.05), respectively. The two immunized groups had fewer intestinal lesions (p < 0.05) and higher IgG levels (p < 0.05). Higher levels of IL-2, IL-4, and IFN-γ cytokines in the rEi-14-3-3 group (p < 0.05) and a higher level of IFN-γ in the rEi-GRA10 group (p < 0.05) were observed. The ACI values of the rEi-14-3-3 and rEi-GRA10 groups were 168.24 and 159.91, with good and moderate protective effects, respectively. Both rEi-14-3-3 and rEi-GRA10 induced humoral immunity in the rabbits. In addition, rEi-14-3-3 induced Th1- and Th2-type immune responses. Both recombinant proteins were protective against E. intestinalis infection in rabbits, with rEi-14-3-3 showing a better protective effect.


Asunto(s)
Coccidiosis , Eimeria , Enfermedades de las Aves de Corral , Vacunas Antiprotozoos , Animales , Conejos , Proteínas 14-3-3 , Coccidiosis/prevención & control , Coccidiosis/veterinaria , Citocinas , Oocistos , Vacunas Sintéticas , Aumento de Peso , Pollos , Enfermedades de las Aves de Corral/prevención & control
9.
Angew Chem Int Ed Engl ; 62(39): e202309158, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37496398

RESUMEN

Catalytic ozone (O3 ) decomposition at high relative humidity (RH) remains a great challenge due to the catalysts poison and deactivation under high humidity. Here, we firstly elaborate the role of water activation and the corresponding mechanism of the promoted O3 decomposition over the three-dimensional monolithic molybdenum oxide/graphdiyne (MoO3 /GDY) catalyst. The O3 decomposition over MoO3 /GDY reaches up to 100 % under high humid condition (75 % RH) at room temperature, which is 4.0 times as high as that of dry conditions, significantly surpasses other carbon-based MoO3 materials(≤7.1 %). The sp-hybridized carbon in GDY donates electrons to MoO3 along the C-O-Mo bond, facilitating water activation to form hydroxyl species. As a result, hydroxyl species dissociated from water act as new active sites, promoting the adsorption of O3 and the generation of new intermediate species (hydroxyl ⋅OH and superoxo ⋅O2 - ), which significantly lowers the energy barriers of O3 decomposition (0.57 eV lower than dry conditions).

10.
J Am Chem Soc ; 144(11): 4942-4951, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35262357

RESUMEN

Activation of O2 is a crucial step in oxidation processes. Here, the concept of sp-hybridized C≡C triple bonds as an electron donor is adopted to develop highly active and stable catalysts for molecular oxygen activation. We demonstrate that the neighboring sp-hybridized C and Cu sites on the interface of the sub-nanocluster CuO/graphdiyne are the key structures to effectively modulate the O2 activation process in the bridging adsorption mode. The as-prepared sub-nanocluster CuO/graphdiyne catalyst exhibited the highest CO oxidation activity and readily converted 50% CO at around 133 °C, which is 34 and 94 °C lower than that for CuO/graphene and CuO/active carbon catalysts, respectively. In situ diffused reflectance infrared Fourier transform spectroscopy and density functional theory calculation results proved that the neighboring sp-hybridized C is more favorable to promote the rapid dissociation of carbonate than sp2-hybridized C without overcoming any energy barrier. The gaseous CO directly reacts with the active molecular oxygen and tends to proceed through the E-R mechanism with a relatively low energy barrier (0.20 eV). This work revealed that sp-hybridized C of graphdiyne-based materials could effectively improve the O2 activation efficiency, which could facilitate the low-temperature oxidation processes.

11.
Environ Sci Technol ; 56(5): 3245-3257, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35005888

RESUMEN

Revealing the role of engineered surface oxygen vacancies in the catalytic degradation of volatile organic compounds (VOCs) is of importance for the development of highly efficient catalysts. However, because of various structures of VOC molecules, the role of surface oxygen vacancies in different catalytic reactions remains ambiguous. Herein, a defective Pt/TiO2-x catalyst is proposed to uncover the different catalytic mechanisms of C3H6 and C3H8 combustion via experiments and theoretical calculations. The electron transfer, originated from the oxygen vacancy, facilitates the formation of reduced Pt0 species and simultaneously interfacial chemisorbed O2, thus promoting the C3H6 combustion via efficient C═C cleavage. The reduced Pt nanoparticles facilitate the robust chemisorption of bridging dimer O22- (Pt-O-O-Ti) species. This chemisorbed oxygen inhibits the C3H8 combustion by depressing C3H8 adsorption. This work offers insights for the rational design of highly efficient catalysts for activating the C═C bond in alkene or C-H bond in alkane.

12.
J Immunol ; 205(9): 2423-2436, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32989093

RESUMEN

Neonatal life marks the apogee of murine thymic growth. Over the first few days after birth, growth slows and the murine thymus switches from fetal to adult morphology and function; little is known about the cues driving this dramatic transition. In this study, we show for the first time (to our knowledge) the critical role of vascular endothelial growth factor (VEGF) on thymic morphogenesis beyond its well-known role in angiogenesis. During a brief window a few days after birth, VEGF inhibition induced rapid and profound remodeling of the endothelial, mesenchymal and epithelial thymic stromal compartments, mimicking changes seen during early adult maturation. Rapid transcriptional changes were seen in each compartment after VEGF inhibition, including genes involved in migration, chemotaxis, and cell adhesion as well as induction of a proinflammatory and proadipogenic signature in endothelium, pericytes, and mesenchyme. Thymocyte numbers fell subsequent to the stromal changes. Expression patterns and functional blockade of the receptors VEGFR2 and NRP1 demonstrated that VEGF mediates its pleiotropic effects through distinct receptors on each microenvironmental compartment of the developing mouse thymus.


Asunto(s)
Timo/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Adhesión Celular/fisiología , Movimiento Celular/fisiología , Endotelio/metabolismo , Mesodermo/metabolismo , Ratones , Ratones Endogámicos C57BL , Neovascularización Patológica/metabolismo , Pericitos/metabolismo , Timocitos/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
13.
Anim Genet ; 53(6): 769-781, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35989407

RESUMEN

Since sow backfat thickness (BFT) is highly correlated with its service life and reproductive effectiveness, dynamic monitoring of BFT is a critical component of large-scale sow farm productivity. Existing contact measures of sow BFT have their problems including, high measurement intensity and sows' stress reaction, low biological safety, and difficulty in meeting the requirements for multiple measurements. This article presents a two-dimensional (2D) image-based approach for determining the BFT of pregnant sows when combined with the backfat growth rate (BGR). The 2D image features of sows extracted by convolutional neural networks (CNN) and the artificially defined phenotypic features of sows such as hip width, hip height, body length, hip height-width ratio, length-width ratio, and waist-hip ratio, were used respectively, combined with BGR, to construct a prediction model for sow BFT using support vector regression (SVR). Following testing and comparison, it was shown that using CNN to extract features from images could effectively replace artificially defined features, BGR contributed to the model's accuracy improvement. The CNN-BGR-SVR model performed the best, with R2 of 0.72 and mean absolute error of 1.21 mm, and root mean square error of 1.50 mm, and mean absolute percentage error of 7.57%. The results demonstrated that the CNN-BGR-SVR model based on 2D images was capable of detecting sow BFT, establishing a new reference for non-contact sow BFT detection technology.


Asunto(s)
Tejido Adiposo , Crianza de Animales Domésticos , Porcinos , Animales , Femenino , Embarazo , Tejido Adiposo/diagnóstico por imagen , Lactancia , Reproducción , Porcinos/fisiología , Crianza de Animales Domésticos/métodos , Diagnóstico por Imagen/veterinaria
14.
Molecules ; 27(22)2022 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-36431931

RESUMEN

Oxidative stress is one of the potential causes of nervous system disease. Ginseng extract possesses excellent antioxidant activity; however, little research on the function of the ginseng fibrous root. This study aimed to investigate the neuroprotective effects of ginseng fibrous root to alleviate the pathogenesis of Alzheimer's disease (AD) against oxidative stress. Ginseng fibrous root enzymatic hydrolysate (GFREH) was first prepared by digesting ginseng fibrous roots with alkaline protease. In vitro, the GFREH showed antioxidant activities in free radical scavenging mechanisms. With a cellular model of AD, GFREH inhibited the increase in Ca2+ levels and intracellular ROS content, maintained the balance of mitochondrial membrane potential, and relieved L-glutamic acid-induced neurotoxicity. In vivo, GFREH improved the survival rate of Caenorhabditis elegans (C. elegans) under oxidative stress, upregulated SOD-3 expression, and reduced reactive oxygen species (ROS) content. Therefore, our findings provide evidence for the alleviation effect of GFREH against oxidative stress in neuroprotection, which may accelerate the development of anti-Alzheimer's drugs and treatments in the future.


Asunto(s)
Fármacos Neuroprotectores , Panax , Animales , Fármacos Neuroprotectores/farmacología , Especies Reactivas de Oxígeno/metabolismo , Caenorhabditis elegans/metabolismo , Estrés Oxidativo , Antioxidantes/farmacología , Antioxidantes/metabolismo , Panax/metabolismo
15.
Angew Chem Int Ed Engl ; 61(48): e202212273, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36196008

RESUMEN

The in-depth mechanism on the simultaneous activation of O2 and surface lattice O2- on one active metallic site has not been elucidated yet. Herein, we report a strategy for the construction of abundant oxygen activation sites by rational design of Cu1 /TiO2 single atom catalysts (SACs). The charge transfer between isolated Cu and TiO2 support generates abundant CuI and 2-coordinated Olat sites in Cu1 -O-Ti hybridization structure, which facilitates the chemisorption and activation of O2 molecules. Simultaneously, the Cu1 -O-Ti induced TiO2 lattice distortion activate the adjacent surface lattice O2- , achieving the dual activation of O2 and surface lattice O2- . The Cu1 -O-Ti active site switches the CO oxidation mechanism from Eley-Rideal (80 °C) to Mars-van Krevelen route (200 °C) with the increase of reaction temperature. The dual activation of O2 and surface lattice O2- can by modulating the electron properties of SACs can boost the heterogeneous catalytic oxidation activity.

16.
J Am Chem Soc ; 143(23): 8720-8730, 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34100598

RESUMEN

High-current density (≥1 A cm-2) is a critical factor for large-scale industrial application of water-splitting electrocatalysts, especially seawater-splitting. However, it still remains a great challenge to reach high-current density due to the lack of active and stable intrinsic catalytic active sites in catalysts. Herein, we report an original three-dimensional self-supporting graphdiyne/molybdenum oxide (GDY/MoO3) material for efficient hydrogen evolution reaction via a rational design of "sp C-O-Mo hybridization" on the interface. The "sp C-O-Mo hybridization" creates new intrinsic catalytic active sites (nonoxygen vacancy sites) and increases the amount of active sites (eight times higher than pure MoO3). The "sp C-O-Mo hybridization" facilitates charge transfer and boosts the dissociation process of H2O molecules, leading to outstanding HER activity with high-current density (>1.2 A cm-2) in alkaline electrolyte and a decent activity and stability in natural seawater. Our results show that high-current density electrocatalysts can be achieved by interfacial chemical bond engineering, three-dimensional structure design, and hydrophilicity optimization.

17.
Metabolomics ; 17(10): 93, 2021 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-34595616

RESUMEN

INTRODUCTION: Intrahepatic cholestasis of pregnancy (ICP) is one of the more common complications in the middle and late stages of pregnancy, which requires early detection and intervention. OBJECTIVE: The aim of the study is to investigate the changes in the metabolic profile of bile acids (BAs) in plasma of pregnant women with ICP and to look biomarkers for the diagnosis and grading of ICP, and to explore the disease mechanism. METHODS: The targeted metabolomics based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to analyze plasma BAs. RESULTS: Twenty-seven BAs can be quantified in all participants. Among them, 22 BAs were identified as differential BAs between ICP and control groups. Five BAs include 3ß-CA, 3ß-DCA, CDCA-3Gln, NCA, and Tß-MCA, were found to be associated with ICP for the first time. Nine BAs include NCA, GCA, GCDCA, GHCA, GUDCA, HCA, TCA, TCDCA and THCA, can be used as possible ICP diagnostic biomarkers. Four BAs, i.e., GLCA, THCA, GHCA and TLCA-3S may be used as potential biomarkers for ICP grading. CONCLUSION: There were significant differences in plasma BA profiles between ICP patients and the control. The BA profiles of mild ICP group and severe ICP group partially overlapped. Potential diagnostic and grading BA markers were identified. A significant characteristic of ICP group was the increase of conjugated BAs. A mechanism to sustain the equilibrium of BA metabolism and adaptive response has been developed in ICP patients to accelerate excretion and detoxification.


Asunto(s)
Ácidos y Sales Biliares , Complicaciones del Embarazo , Biomarcadores , Colestasis Intrahepática , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/diagnóstico , Espectrometría de Masas en Tándem
18.
Metabolomics ; 17(11): 99, 2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34739593

RESUMEN

INTRODUCTION: Gestational diabetes mellitus (GDM) is a common complication during pregnancy. Looking for reliable diagnostic markers for early diagnosis can reduce the impact of the disease on the fetus OBJECTIVE: The present study is designed to find plasma metabolites that can be used as potential biomarkers for GDM, and to clarify GDM-related mechanisms METHODS: By non-target metabolomics analysis, compared with their respective controls, the plasma metabolites of GDM pregnant women at 12-16 weeks and 24-28 weeks of pregnancy were analyzed. Multiple reaction monitoring (MRM) analysis was performed to verify the potential marker RESULTS: One hundred and seventy-two (172) and 478 metabolites were identified as differential metabolites in the plasma of GDM pregnant women at 12-16 weeks and 24-28 weeks of pregnancy, respectively. Among these, 40 metabolites were overlapped. Most of them are associated with the mechanism of diabetes, and related to short-term and long-term complications in the perinatal period. Among them, 7 and 10 differential metabolites may serve as potential biomarkers at the 12-16 weeks and 24-28 weeks of pregnancy, respectively. By MRM analysis, compared with controls, increased levels of 17(S)-HDoHE and sebacic acid may serve as early prediction biomarkers of GDM. At 24-28 weeks of pregnancy, elevated levels of 17(S)-HDoHE and L-Serine may be used as auxiliary diagnostic markers for GDM CONCLUSION: Abnormal amino acid metabolism and lipid metabolism in patients with GDM may be related to GDM pathogenesis. Several differential metabolites identified in this study may serve as potential biomarkers for GDM prediction and diagnosis.


Asunto(s)
Diabetes Gestacional , Biomarcadores , Diabetes Gestacional/diagnóstico , Femenino , Humanos , Metabolismo de los Lípidos , Metabolómica , Embarazo , Mujeres Embarazadas
19.
Environ Sci Technol ; 55(13): 9243-9254, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34106698

RESUMEN

An in-depth understanding of the surface properties-activity relationship could provide a fundamental guidance for the design of highly efficient perovskite-based catalysts for the control of anthropogenic methane emission. Herein, both oxygen vacancies and Con+ Lewis acid sites were purposely introduced on ordered macroporous La0.8Sr0.2CoO3 monolithic catalysts by one-step reduction and selective etching in oxalic acid, and their synergistic effect on methane combustion was investigated. Combined with experimental and theoretical investigations, we revealed that the positively charged Con+ Lewis acid sites and single-electron-trapped oxygen vacancies (Vo·) formed an active pair, which enabled an effective localized electron cloud shift from Vo· to Con+. The characteristic electronic effect modulates surface electronic properties and coordination structures, thus resulting in superior oxygen activation capacity, lattice oxygen mobility, and reducibility, as well as favorable CH4 interaction and oxidation. Our work not only gives insights into surface properties-activity relationships on perovskite for hydrocarbon combustion but also sheds substantial light on future environmental catalyst design and modulation for hydrocarbon pollutants elimination.


Asunto(s)
Ácidos de Lewis , Oxígeno , Compuestos de Calcio , Metano , Óxidos , Titanio
20.
Nat Methods ; 14(5): 521-530, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28369043

RESUMEN

Studies of human T cell development require robust model systems that recapitulate the full span of thymopoiesis, from hematopoietic stem and progenitor cells (HSPCs) through to mature T cells. Existing in vitro models induce T cell commitment from human HSPCs; however, differentiation into mature CD3+TCR-αß+ single-positive CD8+ or CD4+ cells is limited. We describe here a serum-free, artificial thymic organoid (ATO) system that supports efficient and reproducible in vitro differentiation and positive selection of conventional human T cells from all sources of HSPCs. ATO-derived T cells exhibited mature naive phenotypes, a diverse T cell receptor (TCR) repertoire and TCR-dependent function. ATOs initiated with TCR-engineered HSPCs produced T cells with antigen-specific cytotoxicity and near-complete lack of endogenous TCR Vß expression, consistent with allelic exclusion of Vß-encoding loci. ATOs provide a robust tool for studying human T cell differentiation and for the future development of stem-cell-based engineered T cell therapies.


Asunto(s)
Órganos Artificiales , Diferenciación Celular , Células Madre Hematopoyéticas/citología , Organoides/citología , Linfocitos T/citología , Timo/citología , Biotecnología/métodos , Células Madre Hematopoyéticas/inmunología , Humanos , Organoides/inmunología , Células Madre/citología , Células Madre/inmunología , Linfocitos T/inmunología , Timo/inmunología
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