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Complete sample digestion is a prerequisite for acquiring high-quality analytical results for geological samples. Closed-vessel acid digestion (bomb) has typically been used for the total digestion of refractory geological samples. However, the long digestion time (4-5 days) and insoluble fluoride complexes still pose challenges for digesting refractory geological samples using this approach. In this study, an efficient and simplified digestion technique combining ultrafine powders from planetary ball milling with bomb digestion was developed for trace element analysis of refractory geological samples: peridotite and granitoid. The method shows two significant improvements compared with previous approaches. (1) By performing dry planetary ultrafine milling, the initial 200 mesh peridotite (<74 µm) could be reduced to 800 mesh (<20 µm) in 6 min at a ball-to-powder mass ratio of approximately 15 using 3 mm tungsten carbide milling balls. (2) Complete peridotite and granitoid dissolution were achieved in approximately 2 h, 60 times faster than what is achievable using previous methods (2 h vs 120 h). Moreover, ultrafine powders effectively suppressed insoluble fluoride formation during bomb digestion. A suite of peridotite and granitoid reference materials were measured to evaluate the stability of this method. This efficient, simple, and reliable sample digestion method could benefit geological, food, environmental, and other fields requiring solid sample decomposition via wet acid, fusion, combustion, or dry ashing.
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Parkinson's disease (PD) represents the second most widespread neurodegenerative disease, and early monitoring and diagnosis are urgent at present. Tyrosine hydroxylase (TH) is a key enzyme for producing dopamine, the levels of which can serve as an indicator for assessing the severity and progression of PD. This renders the specific detection and visualization of TH a strategically vital way to meet the above demands. However, a fluorescent probe for TH monitoring is still missing. Herein, three rationally designed wash-free ratiometric fluorescent probes were proposed. Among them, TH-1 exhibited ideal photophysical properties and specific dual-channel bioimaging of TH activity in SH-SY5Y nerve cells. Moreover, the probe allowed for in vivo imaging of TH activity in zebrafish brain and living striatal slices of mice. Overall, the ratiometric fluorescent probe TH-1 could serve as a potential tool for real-time monitoring of PD in complex biosystems.
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Corantes Fluorescentes , Tirosina 3-Mono-Oxigenase , Peixe-Zebra , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Tirosina 3-Mono-Oxigenase/metabolismo , Tirosina 3-Mono-Oxigenase/análise , Animais , Camundongos , Humanos , Imagem Óptica , Linhagem Celular Tumoral , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismoRESUMO
G-quadruplex structures within the nuclear genome (nG4) is an important regulatory factor, while the function of G4 in the mitochondrial genome (mtG4) still needs to be explored, especially in human sperms. To gain a better understanding of the relationship between mtG4 and mitochondrial function, it is crucial to develop excellent probes that can selectively visualize and track mtG4 in both somatic cells and sperms. Herein, based on our previous research on purine frameworks, we attempted for the first time to extend the conjugated structure from the C-8 site of purine skeleton and discovered that the purine derivative modified by the C-8 aldehyde group is an ideal platform for constructing near-infrared probes with extremely large Stokes shift (>220 nm). Compared with the compound substituted with methylpyridine (PAP), the molecule substituted with methylthiazole orange (PATO) showed better G4 recognition ability, including longer emission (â¼720 nm), more significant fluorescent enhancement (â¼67-fold), lower background, and excellent photostability. PATO exhibited a sensitive response to mtG4 variation in both somatic cells and human sperms. Most importantly, PATO helped us to discover that mtG4 was significantly increased in cells with mitochondrial respiratory chain damage caused by complex I inhibitors (6-OHDA and rotenone), as well as in human sperms that suffer from oxidative stress. Altogether, our study not only provides a novel ideal molecular platform for constructing high-performance probes but also develops an effective tool for studying the relationship between mtG4 and mitochondrial function in both somatic cells and human sperms.
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Corantes Fluorescentes , Purinas , Humanos , Purinas/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Doenças Mitocondriais/metabolismo , Regulação para Cima , Genoma Mitocondrial , Quadruplex G , Mitocôndrias/metabolismo , Raios Infravermelhos , Células HeLaRESUMO
BACKGROUND: Sleep disturbances in the peri-operative period have been associated with adverse outcomes, including postoperative delirium (POD). However, research on sleep quality during the immediate postoperative period is limited. OBJECTIVES: This study aimed to investigate the association between sleep quality on the night of the operative day assessed using the Sleep Quality Numeric Rating Scale (SQ-NRS), and the incidence of POD in a large cohort of surgical patients. DESIGN: A prospective cohort study. SETTING: A tertiary hospital in China. PATIENTS: This study enrolled patients aged 65âyears or older undergoing elective surgery under general anaesthesia. The participants were categorised into the sleep disturbance and no sleep disturbance groups according to their operative night SQ-NRS. MAIN OUTCOME MEASURES: The primary outcome was delirium incidence, whereas the secondary outcomes included acute kidney injury, stroke, pulmonary infection, cardiovascular complications and all-cause mortality within 1 year postoperatively. RESULTS: In total, 3072 patients were included in the analysis of this study. Among them, 791 (25.72%) experienced sleep disturbances on the night of operative day. Patients in the sleep disturbance group had a significantly higher risk of developing POD (adjusted OR 1.43, 95% CI 1.11 to 1.82, P â=â0.005). Subgroup analysis revealed that age 65-75âyears; male sex; ASA III and IV; haemoglobin more than 12âgâl -1 ; intra-operative hypotension; surgical duration more than 120âmin; and education 9âyears or less were significantly associated with POD. No interaction was observed between the subgroups. No significant differences were observed in the secondary outcomes, such as acute kidney injury, stroke, pulmonary infection, cardiovascular complications and all-cause mortality within 1 year postoperatively. CONCLUSIONS: The poor subjective sleep quality on the night of operative day was independently associated with increased POD risk, especially in certain subpopulations. Optimising peri-operative sleep may reduce POD. Further research should investigate potential mechanisms and causal relationships. TRIAL REGISTRY: chictr.org.cn: ChiCTR1900028545.
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Injúria Renal Aguda , Infecções Cardiovasculares , Delírio , Delírio do Despertar , Acidente Vascular Cerebral , Idoso , Humanos , Masculino , Infecções Cardiovasculares/complicações , Delírio/diagnóstico , Delírio/epidemiologia , Delírio/etiologia , Delírio do Despertar/diagnóstico , Delírio do Despertar/epidemiologia , Delírio do Despertar/etiologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Fatores de Risco , Qualidade do Sono , FemininoRESUMO
Roots are fundamental for plants to adapt to variable environmental conditions. The development of a robust root system is orchestrated by numerous genetic determinants and, among them, the MADS-box gene ANR1 has garnered substantial attention. Prior research has demonstrated that, in chrysanthemum, CmANR1 positively regulates root system development. Nevertheless, the upstream regulators involved in the CmANR1-mediated regulation of root development remain unidentified. In this study, we successfully identified bric-a-brac, tramtrack and broad (BTB) and transcription adapter putative zinc finger (TAZ) domain protein CmBT1 as the interacting partner of CmANR1 through a yeast-two-hybrid (Y2H) screening library. Furthermore, we validated this physical interaction through bimolecular fluorescence complementation and pull-down assays. Functional assays revealed that CmBT1 exerted a negative influence on root development in chrysanthemum. In both in vitro and in vivo assays, it was evident that CmBT1 mediated the ubiquitination of CmANR1 through the ubiquitin/26S proteasome pathway. This ubiquitination subsequently led to the degradation of the CmANR1 protein and a reduction in the transcription of CmANR1-targeted gene CmPIN2, which was crucial for root development in chrysanthemum. Genetic analysis suggested that CmBT1 modulated root development, at least in part, by regulating the level of CmANR1 protein. Collectively, these findings shed new light on the regulatory role of CmBT1 in degrading CmANR1 through ubiquitination, thereby repressing the expression of its targeted gene and inhibiting root development in chrysanthemum.
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Chrysanthemum , Chrysanthemum/genética , Chrysanthemum/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitinação , Ligação Proteica , Dedos de Zinco , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Aberrant lysosomal alkalization is associated with various biological processes, such as oxidative stress, cell apoptosis, ferroptosis, etc. Herein, we developed a novel aminofluorene-based fluorescence probe named FAN to monitor the lysosomal alkalization-related biological processes by its migration from lysosome to nucleus. FAN possessed NIR emission, large Stokes shift, high pH stability, and high photostability, making it suitable for real-time and long-term bioimaging. As a lysosomotropic molecule, FAN can accumulate in lysosomes first and then migrate to the nucleus by right of its binding capability to DNA after lysosomal alkalization. In this manner, FAN was successfully used to monitor these physiological processes which triggered lysosomal alkalization in living cells, including oxidative stress, cell apoptosis, and ferroptosis. More importantly, at higher concentrations, FAN could also serve as a stable nucleus dye for the fluorescence imaging of the nucleus in living cells and tissues. This novel multifunctional fluorescence probe shows great promise for application in lysosomal alkalization-related visual research and nucleus imaging.
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Ferroptose , Corantes Fluorescentes , Corantes Fluorescentes/química , Imagem Óptica , Lisossomos/química , Apoptose/fisiologia , Concentração de Íons de HidrogênioRESUMO
Alzheimer's disease (AD) is a progressive neurodegenerative disease with insidious onset, and the deposition of amyloid-ß (Aß) is believed to be one of the main cause. Fluorescence imaging is a promising technique for this task, but the Aß gold standard probe ThT developed based on this still has shortcomings. The development of a new fluorescent probe to detect Aß plaques is thought to be essential. Herein, a series of red to near-infrared emitting fluorescent probes QNO-ADs with newly quinoxalinone skeleton are designed to detect Aß plaques. They all demonstrate excellent optical properties and high binding affinity (â¼Kd = 20 nM) to Aß aggregates. As the most outstanding candidate, QNO-AD-3 shows significant signal-to-noise (S/N) ratio at the level of in vitro binding studies, and the brilliant fluorescence staining results in favor of grasping the approximate distribution of Aß plaques in the brain slice. In vivo Aß plaques imaging suggests that QNO-AD-3 can cross the BBB and have a long retention time in the brain with low biological toxicity. In addition, the results of docking theoretical calculation also provide some references for the design of Aß probe. Overall, given the high affinity of QNO-AD-3 and the ability to monitor Aß plaques for a long time that is not common now, we believe QNO-AD-3 will be an effective tool for an Aß-related matrix and AD disease research in the future.
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Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/química , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Corantes Fluorescentes/química , Camundongos , Camundongos Transgênicos , Placa Amiloide/diagnóstico por imagemRESUMO
BACKGROUND: Separation of biotic and abiotic impacts on species diversity distribution patterns across a significant climatic gradient is a challenge in the study of diversity maintenance mechanisms. The basic task is to reconcile scale-dependent effects of abiotic and biotic processes on species distribution models. Here, we used a hierarchical modeling method to detect the host specificities of bark beetles (Scolytinae and Platypodinae) with their dependent tree communities across a steep climatic gradient, which was embedded within a relatively homogenous spatial niche. RESULTS: Species turnover of both trees and bark beetles have an opposite pattern along the climatic proxy (represented by the elevation gradients) at the regional scale, but not at local spatial scales. This pattern confirmed the hypothesis wherein emphasis was on influences of macro-climate on local biotic interactions between trees and hosted bark beetle communities, whereas local biotic relations, represented by host specificity dependence, were regionally conserved. CONCLUSIONS: At a confined spatial scale, cross-taxa comparisons of ß-diversity highlighted the importance of simultaneous impacts from both extrinsic factors related to geography and environment, and intrinsic factors related to organism characteristics. The effects of tree abundance and phylogeny diversity on bark beetle diversity were, to a large extent, indirect, operating via changes in bark beetle abundance through spatial and temporal dynamics of resources distribution. Tree host dependence, which was considered and represented by host specificities, plays a minor role on the hosted beetle community in this concealed wood decomposing interacting system.
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Non-invasive dynamic tracking of lysosomes and their interactions with other organelles is important for the study of lysosomal function and related diseases. However, many fluorescent dyes developed so far to target lysosomes cannot be used to monitor these processes due to the high concentrations required for imaging, long cell penetration times, and non-ideal photostability. In this regard, we synthesized three lysosomal targeting probes with large Stokes shifts, good stability, and high brightness. The Q-P-ARh dye, developed by us for the first time, can stain lysosomes at ultra-low concentrations (1.0â nM) without affecting the physiological functions of the lysosomes. More importantly, its excellent anti-interference ability and ultrafast lysosomal staining ability (within 1.0â min) clearly monitored the entire dynamic process of lipophagy. Ultimately, this method can greatly contribute to the study of autophagy pathways. This novel fluorescence platform shows great promise for the development of biological probes for application in pathological environments.
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Autofagia , Fluorescência , Corantes Fluorescentes/química , Imagem Óptica , Corantes Fluorescentes/síntese química , Células Hep G2 , Humanos , Lisossomos/químicaRESUMO
BACKGROUND: Our previous studies demonstrated that the administration of crude Polysaccharide from Panax notoginseng (CPPN) can effectively prolong the lifespan of tumor-bearing mice via boosting the host immune system as well as weak cytotoxicity against hepatocellular carcinoma (HCC). In the present study, Neutral Polysaccharide (NPPN) were further purified from crude polysaccharide isolated from panax notoginseng. The effects of NPPN on the immune function and hematopoietic function of mice with low immunity and myelosuppression induced by cyclophosphamide (CTX) were investigated. The effect of NPPN combined with CTX on the tumor inhibition rate of the H22 tumor-bearing mice and the impact of NPPN on the proliferation of H22 liver cancer cells in vitro were investigated. METHODS: CPPN was obtained by water extraction and alcohol precipitation method, and further purified by DEAE Sepharose Fast Flow ion exchange resin column. NPPN was added to the immunosuppressed with myelosuppression mice induced by CTX. Thymus index, spleen index, lymphocyte proliferation stimulation index by adding of concanavalin A, determination of serum hemolysin, NK cell activity assay, mice carbon clearance experiment, blood count tests were detected. The tumor inhibition rate of the H22 tumor-bearing mice treated with NPPN combined with CTX was recorded. RESULTS: NPPN and 4 kinds of acid polysaccharide from Panax notoginseng (APPN) were successfully isolated from the CPPN by DEAE Sepharose Fast Flow ion exchange resin column. NPPN inhibited the growth of H22 cells and significantly increase the tumor inhibition rate of the H22 tumor-bearing mice combined with CTX. The elevation of the cellular and humoral immunity levels as well as a variety of blood count tests indicators of immunosuppressive with myelosuppression mice may contribute to the antitumor activity of NPPN. CONCLUSION: NPPN has a potential antitumor activity for the treatment of liver cancer combined with cyclophosphamide.
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Carcinoma Hepatocelular/tratamento farmacológico , Ciclofosfamida/farmacologia , Sinergismo Farmacológico , Panax notoginseng/química , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Animais , Antineoplásicos Alquilantes/farmacologia , Apoptose , Carcinoma Hepatocelular/patologia , Proliferação de Células , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: The interactions between nanoparticles (NPs) and plasma proteins form a protein corona around NPs after entering the biological environment, which provides new biological properties to NPs and mediates their interactions with cells and biological barriers. Given the inevitable interactions, we regard nanoparticleâprotein interactions as a tool for designing protein corona-mediated drug delivery systems. Herein, we demonstrate the successful application of protein corona-mediated brain-targeted nanomicelles in the treatment of glioma, loading them with paclitaxel (PTX), and decorating them with amyloid ß-protein (Aß)-CN peptide (PTX/Aß-CN-PMs). Aß-CN peptide, like the Aß1-42 peptide, specifically binds to the lipid-binding domain of apolipoprotein E (ApoE) in vivo to form the ApoE-enriched protein corona surrounding Aß-CN-PMs (ApoE/PTX/Aß-CN-PMs). The receptor-binding domain of the ApoE then combines with low-density lipoprotein receptor (LDLr) and LDLr-related protein 1 receptor (LRP1r) expressed in the blood-brain barrier and glioma, effectively mediating brain-targeted delivery. METHODS: PTX/Aß-CN-PMs were prepared using a film hydration method with sonication, which was simple and feasible. The specific formation of the ApoE-enriched protein corona around nanoparticles was characterized by Western blotting analysis and LC-MS/MS. The in vitro physicochemical properties and in vivo anti-glioma effects of PTX/Aß-CN-PMs were also well studied. RESULTS: The average size and zeta potential of PTX/Aß-CN-PMs and ApoE/PTX/Aß-CN-PMs were 103.1 nm, 172.3 nm, 7.23 mV, and 0.715 mV, respectively. PTX was efficiently loaded into PTX/Aß-CN-PMs, and the PTX release from rhApoE/PTX/Aß-CN-PMs exhibited a sustained-release pattern in vitro. The formation of the ApoE-enriched protein corona significantly improved the cellular uptake of Aß-CN-PMs on C6 cells and human umbilical vein endothelial cells (HUVECs) and enhanced permeability to the blood-brain tumor barrier in vitro. Meanwhile, PTX/Aß-CN-PMs with ApoE-enriched protein corona had a greater ability to inhibit cell proliferation and induce cell apoptosis than taxol. Importantly, PTX/Aß-CN-PMs exhibited better anti-glioma effects and tissue distribution profile with rapid accumulation in glioma tissues in vivo and prolonged median survival of glioma-bearing mice compared to those associated with PMs without the ApoE protein corona. CONCLUSIONS: The designed PTX/Aß-CN-PMs exhibited significantly enhanced anti-glioma efficacy. Importantly, this study provided a strategy for the rational design of a protein corona-based brain-targeted drug delivery system. More crucially, we utilized the unfavorable side of the protein corona and converted it into an advantage to achieve brain-targeted drug delivery.
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Antineoplásicos/administração & dosagem , Apolipoproteínas E/administração & dosagem , Encéfalo/efeitos dos fármacos , Glioma/tratamento farmacológico , Nanopartículas/administração & dosagem , Coroa de Proteína , Peptídeos beta-Amiloides/administração & dosagem , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/farmacocinética , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Apolipoproteínas E/química , Apolipoproteínas E/farmacocinética , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Glioma/metabolismo , Humanos , Camundongos , Micelas , Nanopartículas/química , Paclitaxel/administração & dosagem , Paclitaxel/química , Paclitaxel/farmacocinética , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacocinética , Poliésteres/administração & dosagem , Poliésteres/química , Poliésteres/farmacocinética , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Coroa de Proteína/químicaRESUMO
The SiO2 @SiO2 :Tb(1,2-BDC)3 phen microspheres with monodispersed core-shell structure, are kind of fluorescent particles, which are prepared by a seeded growth method under the catalysis of glacial acetic acid (1,2-BDC, 1,2-benzenedicarboxylic acid; phen, 1,10-phenanthroline). Firstly, silica seed was fabricated by the hydrolysis of ethyl orthosilicate, and the Tb(1,2-BDC)3 phen was prepared by using 1,2-BDC and phen. Then, a thin mesoporous silica shell doped with Tb(1,2-BDC)3 phen was grown on the prepared monodisperse silica colloids. The prepared phosphor was analyzed by Fourier-transform infrared spectroscopy, X-ray diffraction analysis, scanning electron microscopy, transmission electron microscopy, thermogravimetric and fluorescence spectroscopy. The experimental results showed that the diameter of the SiO2 @SiO2 :Tb((1,2-BDC)3 phen microsphere was about 200 nm with a typical core-shell structure, among which the diameter of the silica core was 180 nm, and that of the mesoporous silicon shell doped with terbium complex was about 10 nm. The fluorescence intensity of SiO2 @SiO2 :Tb((1,2-BDC)3 phen microsphere is nearly three times higher than that of Tb((1,2-BDC)3 phen complexes. The prepared microspheres could be widely used in bio-imaging, optoelectronic appliances and medical diagnosis.
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Dióxido de Silício , Térbio , Microscopia Eletrônica de Transmissão , Microesferas , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
A mitochondria targeting and immobilized fluorescent probe (Rd1) using triphenylphosphonium as the targeting group and methoxymaleimide as the fixed site is designed for the detection of ClO-. The methoxymaleimide fixed group can react with nucleophiles, such as the reactive thiol groups present in mitochondrial polypeptides and proteins, and form covalent bonds to immobilize the probe within mitochondria. The immobilization of Rd1 enhances its ability to withstand the risk of leakage from mitochondria. Methoxymaleimide shows better reactivity toward Cys than glutathione (GSH), which decreases the ineffective labeling of GSH when it covalently bonds with the reactive thiol residues of mitochondrial proteins; furthermore, it can resist hydrolysis during a long-term storage in water, compared with the classic benzyl chloride fixed unit. The imaging results indicate that Rd1 displays enhanced retention within the mitochondria of cells and tissues upon the decrease of mitochondrial membrane potential (MMP) caused by different stimulations. Furthermore, it possesses the ability to visualize exogenous and endogenous ClO- in living cells, tissues, and zebrafishes.
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Corantes Fluorescentes/química , Ácido Hipocloroso/química , Ácido Hipocloroso/metabolismo , Mitocôndrias/metabolismo , Células A549 , Animais , Sobrevivência Celular , Humanos , Camundongos , Imagem Óptica , Células RAW 264.7 , Peixe-ZebraRESUMO
The present study was conducted to evaluate the effects of glucose, soya oil or glutamine on jejunal morphology, protein metabolism and protein expression of the mammalian target of rapamycin complex 1 (mTORC1) signalling pathway in jejunal villus or crypt compartment of piglets. Forty-two 21 d-weaned piglets were randomly allotted to one of the three isoenergetic diets formulated with glucose, soya oil or glutamine for 28 d. On day 14 or 28, the proteins in crypt enterocytes were analysed with isobaric tags for relative and absolute quantification and proteins involved in mTORC1 signalling pathway in villus or crypt compartment cells were determined by Western blotting. Our results showed no significant differences (P > 0·05) in jejunal morphology among the three treatments on day 14 or 28. The differentially expressed proteins mainly took part in a few network pathways, including antimicrobial or inflammatory response, cell death and survival, digestive system development and function and carbohydrate metabolism. On day 14 or 28, there were higher protein expression of eukaryotic initiation factor-4E binding protein-1 in jejunal crypt compartment of piglets supplemented with glucose or glutamine compared with soya oil. On day 28, higher protein expression of phosphor-mTOR in crypt compartment was observed in piglets supplemented with glucose compared with the soya oil. In conclusion, the isoenergetic glucose, soya oil or glutamine did not affect the jejunal morphology of piglets; however, they had different effects on the protein metabolism in crypt compartment. Compared with soya oil, glucose or glutamine may be better energy supplies for enterocytes in jejunal crypt compartment.
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Suplementos Nutricionais , Glucose/farmacologia , Glutamina/farmacologia , Óleo de Soja/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Enterócitos/metabolismo , Jejuno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Suínos , DesmameRESUMO
Accurate analysis using a simple and rapid procedure is always the most important pursuit of analytical chemists. In this study, a new sample preparation procedure, namely the shaker cup (SH) method, was designed and compared with two sample preparation procedures, commonly used in the laboratory, from three aspects: homogeneity of the sample-flux mixture, potential for sample contamination, and sample preparation time. For the three methods, a set of 54 certified reference materials (CRMs) was used to establish the calibration curves, while another set of 19 CRMs was measured to validate the results. In the calibration procedures, the matrix effects were corrected using the theoretical alpha coefficient method combined with the experimental coefficient method. The data of the major oxides (SiO2, TiO2, Al2O3, TFe2O3, MnO, MgO, CaO, Na2O, K2O, and P2O5) and minor elements (Cr, Cu, Ba, Ni, Sr, V, Zr, and Zn) obtained by wavelength dispersive X-ray fluorescence spectroscopy (WD-XRF) were compared using two derivative equations based on the findings by Laurence Whitty-Léveillé. The results revealed that the WD-XRF measured values using the SH method best agreed with the values recommended in the literature.
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The construction of efficient and low toxic non-viral gene delivery vectors is of great significance for gene therapy. Herein, two novel polycations were constructed via Michael addition from low molecular weight polyethylenimine (PEI) 600 Da and amino acid-containing linkages. Lysine and histidine were introduced for the purpose of improved DNA binding and pH buffering capacity, respectively. The ester bonds afforded the polymer biodegradability, which was confirmed by the gel permeation chromatography (GPC) measurement. The polymers could well condense DNA into nanoparticles and protect DNA from degradation by nuclease. Compared with PEI 25 kDa, these polymers showed higher transfection efficiency, lower toxicity, and better serum tolerance. Study of this mechanism revealed that the polyplexes enter the cells mainly through caveolae-mediated endocytosis pathway; this, together with their biodegradability, facilitates the internalization of polyplexes and the release of DNA. The results reveal that the amino acid-linked low molecular weight PEI polymers could serve as promising candidates for non-viral gene delivery.
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Aminoácidos/química , DNA/química , Nanopartículas/química , Polietilenoimina/química , Aminoácidos/genética , Aminoácidos/uso terapêutico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , DNA/genética , DNA/uso terapêutico , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Endocitose/efeitos dos fármacos , Técnicas de Transferência de Genes/tendências , Terapia Genética/métodos , Humanos , Peso Molecular , Nanopartículas/uso terapêutico , Plasmídeos/genética , Polietilenoimina/uso terapêutico , Polímeros/químicaRESUMO
The abnormality of the plasma membrane (PM) is an important biomarker for cell status and many diseases. Hence, visualizing the PM, especially in complex systems, is an emerging field in the life sciences, especially in low-resource settings. Herein, we developed a water-soluble PM-specific probe utilizing electrostatic and hydrophobic interaction strategies with aggregation-induced emission as the signal output. The probe could image the PM with many advanced features (wash-free, ultrafast staining process, excellent PM specificity, and good biocompatibility), which were demonstrated by the PM imaging of neurons. The probe allowed for the first time the imaging of erythrocytes in the complex brain environment through a fluorescence-based method. Moreover, the PM of the epidermal and partial view of the eyeball structure of live zebrafish are also revealed.
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Membrana Celular/ultraestrutura , Corantes Fluorescentes/química , Animais , Materiais Biocompatíveis , Epiderme/ultraestrutura , Eritrócitos/ultraestrutura , Olho/ultraestrutura , Humanos , Neurônios/ultraestrutura , Imagem Óptica , Espectrometria de Fluorescência , Peixe-ZebraRESUMO
The gold abundance in basic rocks, which normally varies between 0.5 and 5 ppb, has served as a very important indicator in many geoscience studies, including those focused on the planetary differentiation, redistribution of elements during the crustal process, and ore genesis. However, because gold is a monoisotopic element that exhibits a nugget effect, it is very difficult to quantify its ultra-low levels in rocks, which significantly limits our understanding of the origin of gold and its circulation between the Earth crust, mantle, and core. In this work, we summarize various sample digestion and combined preconcentration methods for the determination of gold amounts in rocks. They include fire assay, fire assay combined with Te coprecipitation and instrumental neutron activation analysis (INAA) or laser ablation inductively coupled plasma mass spectrometry, fusion combined with Te coprecipitation and anion exchange resins, dry chlorination, wet acid digestion combined with precipitation, ion exchange resins, solvent extraction, polyurethane foam, extraction chromatography, novel solid adsorbents, and direct determination by INAA. In addition, the faced challenges and future perspectives in this field are discussed.
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Química Inorgânica/métodos , Sedimentos Geológicos/química , Ouro/análise , Ácidos/química , Precipitação Química , Microextração em Fase LíquidaRESUMO
The viscosity of lysosome is reported to be a key indicator of lysosomal functionality. However, the existing mechanical methods of viscosity measurement can hardly be applied at the cellular or subcellular level. Herein, a BODIPY-based two-photon fluorescent probe was presented for monitoring lysosomal viscosity with high spatial and temporal resolution. By installing two morpholine moieties to the fluorophore as target and rotational groups, the TICT effect between the two morpholine rings and the main fluorophore scaffold endowed the probe with excellent viscosity sensitivity. Moreover, Lyso-B succeeded in showing the impact of dexamethasone on lysosomal viscosity in real time.
Assuntos
Compostos de Boro/química , Fluorescência , Corantes Fluorescentes/química , Imagem Óptica , Fótons , Células HeLa , Humanos , Lisossomos/química , Microscopia Confocal , Estrutura Molecular , Fatores de Tempo , ViscosidadeRESUMO
PURPOSE: Endothelial damages are one of the most important causes of persistent hypertensive complications. The aim of our study was to discuss the relationship between the molecular markers of endothelial damage, thrombomodulin, and complications in hypertension. METHODS: A total 132 cases of hypertensive patients, including 13 patients with damage of target organs, were selected as research subjects. And grouping was based on different levels of blood pressure. The blood pressure and thrombomodulin levels were detected among all cases, and their drinking, smoking, and other medical records were tracked. RESULTS: Higher plasma concentration of thrombomodulin was demonstrated in subjects with hypertensive complications compared with without complications [24.5 (18.1,37.55) vs 12.1 (9.1,22.3) TU/mL, P = .001, respectively]. The optimum thrombomodulin cutoff value was determined to be more than 15.5 TU/mL, with a sensitivity of 92.3% and a specificity of 63%. With the increase in blood pressure level, thrombomodulin levels in three groups gradually raised [6.15(5.475,12.75) vs 9.75(7.725,13.35) vs 16.45 (10.125,23.725) TU/mL, P = .007, respectively]. CONCLUSION: With the increase in blood pressure and the occurrence of complications, thrombomodulin showed an increasing trend, which was caused by an increase in the degree of endothelial injury. So, thrombomodulin may serve as a clinically meaningful marker of the progression of hypertension.