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1.
Nature ; 595(7867): 370-372, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34262209

RESUMO

Isotope abundance ratios have an important role in astronomy and planetary sciences, providing insights into the origin and evolution of the Solar System, interstellar chemistry and stellar nucleosynthesis1,2. In contrast to deuterium/hydrogen ratios, carbon isotope ratios are found to be roughly constant (around 89) in the Solar System1,3, but do vary on galactic scales with a 12C/13C isotopologue ratio of around 68 in the current local interstellar medium4-6. In molecular clouds and protoplanetary disks, 12CO/13CO ratios can be altered by ice and gas partitioning7, low-temperature isotopic ion-exchange reactions8 and isotope-selective photodissociation9. Here we report observations of 13CO in the atmosphere of the young, accreting super-Jupiter TYC 8998-760-1 b, at a statistical significance of more than six sigma. Marginalizing over the planet's atmospheric temperature structure, chemical composition and spectral calibration uncertainties suggests a 12CO/13CO ratio of [Formula: see text](90% confidence), a substantial enrichment in 13C with respect to the terrestrial standard and the local interstellar value. As the current location of TYC 8998-760-1 b at greater than or equal to 160 astronomical units is far beyond the CO snowline, we postulate that it accreted a substantial fraction of its carbon from ices enriched in 13C through fractionation.

2.
J Exp Bot ; 75(7): 2064-2083, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38011680

RESUMO

Plant diseases tend to be more serious under conditions of high-temperature/high-humidity (HTHH) than under moderate conditions, and hence disease resistance under HTHH is an important determinant for plant survival. However, how plants cope with diseases under HTHH remains poorly understood. In this study, we used the pathosystem consisting of pepper (Capsicum annuum) and Ralstonia solanacearum (bacterial wilt) as a model to examine the functions of the protein mildew resistance locus O 1 (CaMLO1) and U-box domain-containing protein 21 (CaPUB21) under conditions of 80% humidity and either 28 °C or 37 °C. Expression profiling, loss- and gain-of-function assays involving virus-induced gene-silencing and overexpression in pepper plants, and protein-protein interaction assays were conducted, and the results showed that CaMLO1 acted negatively in pepper immunity against R. solanacearum at 28 °C but positively at 37 °C. In contrast, CaPUB21 acted positively in immunity at 28 °C but negatively at 37 °C. Importantly, CaPUB21 interacted with CaMLO1 under all of the tested conditions, but only the interaction in response to R. solanacearum at 37 °C or to exposure to 37 °C alone led to CaMLO1 degradation, thereby turning off defence responses against R. solanacearum at 37 °C and under high-temperature stress to conserve resources. Thus, we show that CaMLO1 and CaPUB21 interact with each other and function distinctly in pepper immunity against R. solanacearum in an environment-dependent manner.


Assuntos
Capsicum , Ralstonia solanacearum , Termotolerância , Imunidade Vegetal/fisiologia , Temperatura , Proteínas de Plantas/metabolismo , Resistência à Doença , Doenças das Plantas/microbiologia , Ralstonia solanacearum/fisiologia , Capsicum/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Eur Spine J ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509262

RESUMO

AIMS: This research aims to construct and verify an accurate nomogram for forecasting the 3-, 5-, and 7-year outcomes in pediatric patients afflicted with spinal cord injury (SCI). METHODS: Pediatric patients with SCI from multiple hospitals in China, diagnosed between Jan 2005 and Jan 2020, were incorporated into this research. Half of these patients were arbitrarily chosen for training sets, and the other half were designated for external validation sets. The Cox hazard model was employed to pinpoint potential prognosis determinants related to the American Spinal Injury Association (ASIA) and Functional Independence Assessment (FIM) index. These determinants were then employed to formulate the prognostic nomogram. Subsequently, the bootstrap technique was applied to validate the derived model internally. RESULTS: In total, 224 children with SCI were considered for the final evaluation, having a median monitoring duration of 68.0 months. The predictive nomogram showcased superior differentiation capabilities, yielding a refined C-index of 0.924 (95% CI: 0.883-0.965) for the training cohort and a C-index of 0.863 (95% CI: 0.735-0.933) for the external verification group. Additionally, when applying the aforementioned model to prognostic predictions as classified by the FIM, it demonstrated a high predictive value with a C-index of 0.908 (95% CI: 0.863-0.953). Moreover, the calibration diagrams indicated a consistent match between the projected and genuine ASIA outcomes across both sets. CONCLUSION: The crafted and verified prognostic nomogram emerges as a dependable instrument to foresee the 3-, 5-, and 7-year ASIA and FIM outcomes for children suffering from SCI.

4.
Spinal Cord ; 62(4): 183-191, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38409493

RESUMO

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Hospital-acquired infections (HAIs) pose a significant risk for pediatric patients with spinal cord injuries (SCIs), potentially leading to extended hospital stays and increased morbidity. This study aims to identify patients at higher risk for HAIs. SETTING: Hospitals from multiple areas in China. METHODS: This retrospective study included 220 pediatric SCI patients from Jan 2005 to Dec 2023, divided into a training set (n = 154) and a validation set (n = 66). We conducted a multivariate logistic regression analysis to identify risk factors associated with HAIs and constructed a predictive nomogram. The model's performance was assessed using receiver operating characteristic (ROC) curves, area under the ROC curve (AUC) and calibration plots, while decision curve analysis was utilized to determine clinical utility. RESULTS: The nomogram incorporated age, time from injury to the hospital, history of urinary and pulmonary infections, urobilinogen positivity, damaged segments, and admission American Spinal Injury Association (ASIA) scores. The model demonstrated excellent discrimination in the training set (AUC = 0.957) and good discrimination in the validation set (AUC = 0.919). Calibration plots indicated an acceptable fit between predicted probabilities and observed outcomes. Decision curve analysis confirmed the model's net benefit over clinical decision thresholds in both sets. CONCLUSION: We developed and validated a predictive nomogram for HAIs in pediatric SCI patients that shows promise for clinical application. The model can assist healthcare providers in identifying patients at higher risk for HAIs, potentially facilitating early interventions and improved patient care strategies.


Assuntos
Traumatismos da Medula Espinal , Humanos , Criança , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/epidemiologia , Estudos Retrospectivos , Nomogramas , Hospitais , Fatores de Risco
5.
Sensors (Basel) ; 24(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38794056

RESUMO

Regional lung ventilation assessment is a critical tool for the early detection of lung diseases and postoperative evaluation. Biosensor-based impedance measurements, known for their non-invasive nature, among other benefits, have garnered significant attention compared to traditional detection methods that utilize pressure sensors. However, solely utilizing overall thoracic impedance fails to accurately capture changes in regional lung air volume. This study introduces an assessment method for lung ventilation that utilizes impedance data from the five lobes, develops a nonlinear model correlating regional impedance with lung air volume, and formulates an approach to identify regional ventilation obstructions based on impedance variations in affected areas. The electrode configuration for the five lung lobes was established through numerical simulations, revealing a power-function nonlinear relationship between regional impedance and air volume changes. An analysis of 389 pulmonary function tests refined the equations for calculating pulmonary function parameters, taking into account individual differences. Validation tests on 30 cases indicated maximum relative errors of 0.82% for FVC and 0.98% for FEV1, all within the 95% confidence intervals. The index for assessing regional ventilation impairment was corroborated by CT scans in 50 critical care cases, with 10 validation trials showing agreement with CT lesion localization results.


Assuntos
Impedância Elétrica , Pulmão , Ventilação Pulmonar , Testes de Função Respiratória , Humanos , Pulmão/diagnóstico por imagem , Pulmão/fisiologia , Pulmão/fisiopatologia , Testes de Função Respiratória/métodos , Ventilação Pulmonar/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Tomografia Computadorizada por Raios X/métodos , Técnicas Biossensoriais/métodos , Eletrodos
6.
Arch Orthop Trauma Surg ; 144(4): 1557-1563, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38386065

RESUMO

INTRODUCTION: The current published evidence for the treatment of developmental dysplasia of the hip (DDH) with failed closed reduction (CR) following failed Pavlik harness (PH) treatment is still limited. This study aimed to determine whether an one-stage open reduction (OR) would lead to a similar outcome to a two-stage OR in these patients. Meanwhile, the occurrence of femoral head avascular necrosis (AVN) and further surgery (pelvic osteotomy, PO) within the follow-up period was investigated. MATERIALS AND METHODS: A consecutive series of DDH patients who failed CR following failed PH treatment and received OR finally between January 2008 and December 2020 were studied. The patients were divided into two groups. One group of which received OR immediately after failed CR (one-stage OR group, Group A), and the other received a delayed OR (two-stage OR group, Group B). The McKay's criteria, acetabular index (AI) and the degree of dislocation of the hips were evaluated for the final outcomes. RESULTS: At the last follow-up, 54 (84.4%) of the 64 hips in Group A and 26 (83.9%) of 31 hips in Group B were in excellent or good condition. Comparison between the two groups revealed that there were no differences in terms of McKay grading (P = 0.950), AI (P = 0.783), incidence of AVN (P = 0.745), and also incidence of PO (P = 1.000). However, a significant lower mean AI was found in Group A, when the OR was performed in Group B (31.06 ± 4.45° vs. 33.87 ± 4.12°, P = 0.004). CONCLUSION: Both of the one- and two-stage OR may acheive favorable outcomes. Moreover, one-stage OR is of without the general anesthesia risk associated with two-stage OR. We therefore advocate that an OR should be performed in appropriate DDH patients during the same session once a failed CR is detected.


Assuntos
Displasia do Desenvolvimento do Quadril , Luxação Congênita de Quadril , Humanos , Lactente , Luxação Congênita de Quadril/cirurgia , Resultado do Tratamento , Displasia do Desenvolvimento do Quadril/cirurgia , Estudos Retrospectivos , Acetábulo
7.
J Exp Bot ; 74(12): 3667-3683, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-36912616

RESUMO

Pepper (Capsicum annuum) employs distinct defence responses against Ralstonia solanacearum infection (RSI); however, the mechanisms by which pepper activates these defence responses in a context-dependent manner is unclear. Here we study pepper plants defence response to RSI under room temperature-high humidity (RSRT, 28 °C / 90%) and high temperature-high humidity (RSHT, 37 °C / 90%) conditions, and non-infected plants under high temperature-high humidity (HTHH, 42 °C / 90%) stress. Herein, we found that the MADS-box transcription factor CaAGL8 was up-regulated by HTHH stress and RSRT or RSHT, and its silencing significantly reduced pepper thermotolerance and susceptibility to infection under both room and high temperature-high humidity (RSRT and RSHT). This was coupled with down-regulation of CaSTH2 and CaDEF1 upon RSRT, down-regulation of CaMgst3 and CaPRP1 upon RSHT, and down-regulation of CaHSP24 upon HTHH. In contrast, the ectopic overexpression of CaAGL8 significantly increased the resistance of Nicotiana benthamiana plants to RSRT, RSHT, and HTHH. In addition, CaAGL8 was found to interact with CaSWC4, which acted as a positive regulator of the pepper response to RSRT, RSHT, and HTHH. Silencing of either CaAGL8 or CaSWC4 blocked the hypersensitive response (HR) cell death and context-dependent up-regulation of defence-related genes triggered by the other. Importantly, enrichment of H4K5Ac, H3K9Ac, H3K4me3, and H3K9me2 on the tested defence-related genes was context- and gene-specifically regulated through synergistic interaction between CaSWC4 and CaAGL8. Our results indicate that pepper employs CaAGL8 to modulate chromatin remodelling by interacting with CaSWC4, thereby activating defence responses to RSRT, RSHT, and HTHH.


Assuntos
Capsicum , Ralstonia solanacearum , Termotolerância , Reguladores de Crescimento de Plantas/genética , Resistência à Doença/genética , Imunidade Vegetal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Montagem e Desmontagem da Cromatina , Cromatina , Capsicum/metabolismo , Doenças das Plantas , Regulação da Expressão Gênica de Plantas , Ralstonia solanacearum/fisiologia
8.
Microb Pathog ; 182: 106263, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37481005

RESUMO

The identification and characterization of functional cis-acting elements is of fundamental importance for comprehending the regulatory mechanisms of gene transcription and bacterial pathogenesis. The transcription factor RegR has been demonstrated to control both competence and virulence in Streptococcus pneumoniae. Despite the clear contribution of RegR to these pathways, the mechanisms underlying its transcriptional regulation remain poorly understood. In this study, we conducted mutational analysis, gene dissection and luciferase activity assays to characterize the cis-elements situated upstream of the regR gene. Our findings revealed that a 311 bp 3'-terminal DNA sequence of the spd0300 gene represents a central region of the upstream cis-acting element of regR. Further investigations identified two structurally similar enhancer-like sequences within this region which feature prominently in the regulation of regR transcription. Furthermore, employing DNA pull-down assays allowed us to enrich the trans-acting factors with the potential to interact with these cis-acting elements. Notably, we found that the competence regulator ComE was implicated in the regulation of regR transcription, a finding which was corroborated by electrophoretic mobility shift assays (EMSA) and quantitative real-time PCR analyses (qRT-PCR). Taken together, our data thus provide fresh insight into the transcriptional regulation of regR.


Assuntos
Proteínas de Bactérias , Streptococcus pneumoniae , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Fatores de Transcrição/genética , Sequência de Bases , Regulação da Expressão Gênica , Transcrição Gênica
9.
Biotechnol Bioeng ; 120(4): 1147-1158, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36593696

RESUMO

As a plant-derived pentacyclic triterpenoid, ß-amyrin has been heterogeneously synthesized in Saccharomyces cerevisiae. However, ß-amyrin is intracellularly produced in a lower gram scale using recombinant S. cerevisiae, which limits the industrial applications. Although many strategies have been proven to be effective to improve the production of ß-amyrin, the intracellularly accumulation is still a challenge in reaching higher titer and simplifying the extraction process. To solve this problem, the amphiphilic ß-cyclodextrin (ß-CD) has been previously employed to aid the efflux of ß-amyrin out of the cells. Nevertheless, the supplemented ß-CD in the medium is not consistent with ß-amyrin synthesis and has the disadvantage of rather high cost. Therefore, an aided-efflux system based on in situ synthesis of ß-CD was developed in this study to enhance the biosynthesis of ß-amyrin and its efflux. The in situ synthesis of ß-CD was started from starch by the surface displayed cyclodextrin glycosyltransferase (CGTase) on yeast cells. As a result, the synthesized ß-CD could capture 16% of the intracellular ß-amyrin and improve the total production by 77%. Furthermore, more strategies including inducing system remodeling, precursor supply enhancement, two-phase fermentation and lipid synthesis regulation were employed. Finally, the production of ß-amyrin was increased to 73 mg/L in shake flask, 31 folds higher than the original strain, containing 31 mg/L of extracellular ß-amyrin. Overall, this work provides novel strategies for the aided-efflux of natural products with high hydrophobicity in engineered S. cerevisiae.


Assuntos
Ácido Oleanólico , Triterpenos , beta-Ciclodextrinas , Saccharomyces cerevisiae
10.
Appl Opt ; 62(33): 8945-8950, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38038042

RESUMO

In laser-plasma experiments, the beam-splitting Faraday rotation measurement is usually used for mapping the magnetic field. Due to the geometric characteristics of the beam-splitting configuration, the split beams are not always incident normally on the image plane, and their spots have different shapes and intensity distributions. Ignoring these issues will inevitably introduce errors in polarization calculation and then generate large false magnetic fields. We introduced the restoration method to recover the spots and suppress the false magnetic field. We applied this method to ZEMAX simulation data and Shenguang-II experimental data. Compared to the method of directly overlaying the spots, it can reduce the average false magnetic field by about 50%. And the false magnetic field at the edge of the spot is reduced by one order of magnitude. We can highly improve the accuracy of the magnetic field measurement with the Faraday rotation method.

11.
Arch Virol ; 167(8): 1619-1636, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35648293

RESUMO

Herpes simplex virus type 1 (HSV-1) is a common pathogen that infects 50-90% of the world's population and causes a variety of diseases, some of which can be life-threatening. Silver nanoparticles (AgNPs) have been shown to have broad-spectrum antiviral activity. In this study, we investigated the activity of AgNPs against HSV-1 and found that AgNPs effectively inhibited plaque formation and HSV-1 progeny production, reduced the genomic load, and interfered with HSV-1 mRNA expression and protein synthesis. Transmission electron microscopy showed that AgNPs interacted with HSV-1 and altered the shape of the viral particles. Furthermore, AgNPs affected the entry of HSV-1 into cells as well as their release and cell-to-cell spread. AgNPs were also found to downregulate the expression of pro-inflammatory cytokines upon HSV-1 infection. Combined treatment with AgNPs and acyclovir (ACV) confirmed that AgNPs significantly enhanced the inhibitory effect of ACV against HSV-1. Our findings may contribute to an understanding of the mechanism of the antiviral effect of AgNPs against HSV-1 and help to provide a theoretical basis for their clinical application.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Nanopartículas Metálicas , Aciclovir/farmacologia , Antivirais/farmacologia , Antivirais/uso terapêutico , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 2 , Humanos , Prata/farmacologia , Prata/uso terapêutico
12.
Biochem Biophys Res Commun ; 553: 126-133, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33770577

RESUMO

Circular RNA (circRNA) homeodomain-interacting protein kinase 3 (circ_HIPK3) has recently reported as regulator in spinal cord injury (SCI). The regulatory mechanism of circ_HIPK3 in SCI was further researched in this study. Circ_HIPK3 expression was inhibited by CoCl2 in AGE1.HN cells. The CoCl2-induced cell cycle arrest, cell proliferation inhibition and apoptosis promotion were mitigated by overexpression of circ_HIPK3. Circ_HIPK3 could target miR-222-3p and circ_HIPK3 repressed the CoCl2-induced neuronal cell injury by sponging miR-222-3p. DUSP19 was a target gene of miR-222-3p and circ_HIPK3 affected the expression of DUSP19 via binding to miR-222-3p. The regulation of circ_HIPK3 in CoCl2-induced injury of AGE1.HN cells was associated with the upregulation of DUSP19. Circ_HIPK3 acted as a pathogenic inhibitor in the progression of SCI via the miR-222-3p-mediated DUSP19 upregulation.


Assuntos
Apoptose/efeitos dos fármacos , Cobalto/farmacologia , Fosfatases de Especificidade Dupla/genética , MicroRNAs/genética , Neurônios/efeitos dos fármacos , Neurônios/patologia , RNA Circular/genética , Sequência de Bases , Linhagem Celular , Fosfatases de Especificidade Dupla/biossíntese , Fosfatases de Especificidade Dupla/deficiência , Fosfatases de Especificidade Dupla/metabolismo , Humanos , RNA Circular/deficiência
13.
Sensors (Basel) ; 21(7)2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807200

RESUMO

Magnetic nanoparticles (MNPs) can work as temperature sensors to realize temperature measurement due to the excellent temperature sensitivity of their magnetization. This paper mainly reports on a performance optimization method of MNPs DC thermometry model. Firstly, by exploring the influencing factors of MNPs magnetization temperature sensitivity, it is found that the optimal excitation of the magnetic field to make the temperature sensitivity of MNPs reach their optimal value is, approximately, inversely proportional to the particle size of MNPs. Then, the temperature sensitivity of MNP magnetization is modulated by adding appropriate DC bias magnetic field in the original triangular wave excitation field, to optimize the original DC thermometry model based on MNP magnetization. The simulation results show that the temperature measurement performance of small-size MNPs can be significantly improved. In short, this paper optimizes the temperature measurement performance of the original DC thermometry model based on MNP magnetization and provides a new application idea for temperature measurement of small-size MNPs.

14.
Sensors (Basel) ; 21(2)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435496

RESUMO

Joints between diaphragm wall panels are weak spots in wall construction. It is essential that potential leak sites are detected prior to excavation. In this study, a novel leak detection and monitoring system is presented that is based on fiber Bragg grating (FBG) sensing technology. A field study was performed in a deep excavation supported by diaphragm walls (in Hohhot, China) to validate the feasibility and effectiveness of the proposed method. Two schemes were trialed; one using pipes made of stainless steel, and one used a pipeless method. The results of the field study are presented and discussed. They show that potential leak sites in the wall joints could be determined prior to excavation using the proposed detection method. Stainless steel is a good material to use to make the detection tube because it can protect the FBG sensors and heating belts from damage and is more sensitive to water leakage. The field study provides good evidence for the feasibility of the new detection system. It also provides valuable experience for the field application of the system and has generated useful data to use in follow-up work.

15.
J Proteome Res ; 19(8): 3109-3122, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32567865

RESUMO

The decline of clinically effective antibiotics has made it necessary to develop more effective antimicrobial agents, especially for refractory biofilm-related infections. Silver nanoparticles (AgNPs) are a new type of antimicrobial agent that can eradicate biofilms and reduce bacterial resistance, but its anti-biofilm mechanism has not been elucidated. In this study, we investigated the molecular mechanism of AgNPs against multidrug-resistant Pseudomonas aeruginosa by means of anti-biofilm tests, scanning electron microscopy (SEM), and tandem mass tag (TMT)-labeled quantitative proteomics. The results of anti-biofilm tests demonstrated that AgNPs inhibited the formation of P. aeruginosa biofilm and disrupted its preformed biofilm. SEM showed that when exposed to AgNPs, the structure of the P. aeruginosa biofilm was destroyed, along with significant reduction of its biomass. TMT-labeled quantitative proteomic analysis revealed that AgNPs could defeat the P. aeruginosa biofilm in multiple ways by inhibiting its adhesion and motility, stimulating strong oxidative stress response, destroying iron homeostasis, blocking aerobic and anaerobic respiration, and affecting quorum sensing systems. Our findings offer a new insight into clarifying the mechanism of AgNPs against biofilms, thus providing a theoretical basis for its clinical application.


Assuntos
Nanopartículas Metálicas , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana , Proteômica , Prata/farmacologia
16.
Nanotechnology ; 31(34): 345101, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32408274

RESUMO

This paper reports on a highly accurate approach of magnetic resonance (MR) thermometry using iron oxide magnetic nanoparticles (MNPs) as temperature sensors. An empirical model for the description of the temperature dependent R 2 relaxation rate is proposed by taking into account the temperature sensitivity of the MNP magnetization. The temperature sensitivity of the MNP magnetization (η) and the temperature sensitivity of the R 2 relaxation rate (κ) are simulated with the proposed empirical models to investigate their dependence on the magnetic field and the particle size. Simulation results show the existence of optimal magnetic fields Hoη and Hoκ that maximize the temperature sensitivities η and κ. Furthermore, simulations and experiments demonstrate that the optimal magnetic field Hoη (Hoκ ) decreases with increasing the particle size. Experiments on temperature dependent R 2 relaxation rate are performed at different magnetic fields for MNP samples with different iron concentrations. Experimental results show that the proposed MR thermometry using MNPs as temperature sensors allows a temperature estimation accuracy of about 0.05 °C. We believe that the achieved approach of highly accurate MR thermometry is of great interest and significance to biomedicine and biology.

17.
Int J Med Sci ; 17(7): 892-902, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32308542

RESUMO

Owing to the rapid development and wide clinical application of direct acting antiviral (DAA) drugs in the treatment of hepatitis C virus (HCV) infection, the era of interferon-based therapy has almost come to an end. Cumulative studies show that DAA therapy renders high cure efficiency (>90%) and good safety profile, and may even bring some unexpected benefits to the patients. However, some issues of concern arise, one of which is the resistance mutation of HCV genome leading to failure of treatment. With the aim of providing some meaningful references for the treatment of chronic hepatitis C (CHC), this article summarizes the research progress on benefits of DAA accompanied by viral clearance in the treatment of chronic hepatitis and the drug resistance.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Farmacorresistência Viral/efeitos dos fármacos , Glucose/metabolismo , Hepacivirus/genética , Hepatite C Crônica/metabolismo , Hepatite C Crônica/fisiopatologia , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/fisiologia , Fígado/virologia , Testes de Função Hepática
18.
J Environ Manage ; 270: 110954, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721361

RESUMO

Food waste is considered a serious global societal problem. How to degrade of food waste in a green and effective way has been to a hot topic. In this work, a method with hot water extraction pretreatment of food waste was investigated and optimized. Under the optimal conditions, more than half of the solid food waste could be transferred to soluble sugars. Meanwhile, in order to improve the tolerance of Rhizopus arrhizus on the food waste hydrolysate, UV combined with chemical mutagenesis were carried out, and a mutant of Rhizopus RH-7-13-807 was obtained. With the mutant strain, the yield of fumaric acid fermented from food waste increased to 1.8 times compared with the original strain, and 23.94 g/L fumaric acid was obtained from the fermentation. Besides, the COD of food waste was evaluated for the degradation of food waste by the Rhizopus RH-7-13-807. The process would decrease the quantity of food waste to be disposed of, and benefit the environment.


Assuntos
Eliminação de Resíduos , Rhizopus , Fermentação , Alimentos , Fumaratos , Hidrólise
19.
Sensors (Basel) ; 19(15)2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31382433

RESUMO

Magnetic iron oxide nanoparticles are relatively advanced nanomaterials, and are widely used in biology, physics and medicine, especially as contrast agents for magnetic resonance imaging. Characterization of the properties of magnetic nanoparticles plays an important role in the application of magnetic particles. As a contrast agent, the relaxation rate directly affects image enhancement. We characterized a series of monodispersed magnetic nanoparticles using different methods and measured their relaxation rates using a 0.47 T low-field Nuclear Magnetic Resonance instrument. Generally speaking, the properties of magnetic nanoparticles are closely related to their particle sizes; however, neither longitudinal relaxation rate r 1 nor transverse relaxation rate r 2 changes monotonously with the particle size d . Therefore, size can affect the magnetism of magnetic nanoparticles, but it is not the only factor. Then, we defined the relaxation rates r i ' (i = 1 or 2) using the induced magnetization of magnetic nanoparticles, and found that the correlation relationship between r 1 ' relaxation rate and r 1 relaxation rate is slightly worse, with a correlation coefficient of R 2 = 0.8939, while the correlation relationship between r 2 ' relaxation rate and r 2 relaxation rate is very obvious, with a correlation coefficient of R 2 = 0.9983. The main reason is that r 2 relaxation rate is related to the magnetic field inhomogeneity, produced by magnetic nanoparticles; however r 1 relaxation rate is mainly a result of the direct interaction of hydrogen nucleus in water molecules and the metal ions in magnetic nanoparticles to shorten the T 1 relaxation time, so it is not directly related to magnetic field inhomogeneity.


Assuntos
Nanopartículas de Magnetita/química , Meios de Contraste/química , Difusão Dinâmica da Luz , Compostos Férricos/química , Modelos Lineares , Campos Magnéticos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Tamanho da Partícula
20.
J Cell Biochem ; 118(10): 3341-3348, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28295550

RESUMO

Long non-coding RNAs (lncRNAs) can participate in the pathological process of multiple myeloma (MM) via regulation of specific gene expression and function. This research aimed to study the role of MALAT-1 and the underlying mechanism in MM. In this study, the expression of MALAT-1 and HMGB1 protein in the bone marrow mononuclear cells from MM patients at different stages and in MM cell lines was determined by qRT-PCR and western blot, respectively. The endogenous expression of MALAT-1 and HMGB1 was modulated using lentivirus vectors transfection. CHX chase assay and RIP analyses were performed to explore the interaction between MALAT-1 and HMGB1 in MM. Nude mouse xenograft was made and used for in vivo experiment study. The expression of MALAT-1 and HMGB1 in the bone marrow mononuclear cells from patients with untreated multiple myeloma was dramatically increased, as well as in MM cell lines, KM3 and U266; while MALAT-1 expression and HMGB1 protein level both decreased significantly in complete remission patients. Furthermore, MALAT-1 knockdown facilitated the degradation of HMGB1 at the post-translational level via increase of the ubiquitination of HMGB1 in MM cells. MALAT-1 was shown to promote autophagy in MM through upregulation of HMGB1. In vivo, MALAT-1 knockdown could inhibit tumor growth significantly in tumor-bearing mice and reduced the protein expressions of HMGB1, Beclin-1, and LC3B in tumor tissues. LncRNA MALAT-1 increases the expression level of HMGB1 in MM thereby promotes autophagy resulting in the inhibition of apoptosis. J. Cell. Biochem. 118: 3341-3348, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Apoptose , Autofagia , Proteína HMGB1/biossíntese , Mieloma Múltiplo/metabolismo , Proteínas de Neoplasias/biossíntese , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Proteína HMGB1/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Proteínas de Neoplasias/genética , RNA Longo não Codificante/genética , RNA Neoplásico/genética
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