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1.
Mol Cell ; 84(2): 244-260.e7, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38101414

RESUMO

Eukaryotic DNA is packaged into chromatin in the nucleus, restricting the binding of transcription factors (TFs) to their target DNA sites. FOXA1 functions as a pioneer TF to bind condensed chromatin and initiate the opening of local chromatin for gene expression. However, the principles of FOXA1 recruitment and how it subsequently unpacks the condensed chromatin remain elusive. Here, we revealed that FOXA1 intrinsically forms submicron-sized condensates through its N- and C-terminal intrinsically disordered regions (IDRs). Notably, both IDRs enable FOXA1 to dissolve the condensed chromatin. In addition, the DNA-binding capacity of FOXA1 contributes to its ability to both form condensates and dissolve condensed chromatin. Further genome-wide investigation showed that IDRs enable FOXA1 to bind and unpack the condensed chromatin to regulate the proliferation and migration of breast cancer cells. This work provides a principle of how pioneer TFs function to initiate competent chromatin states using their IDRs.


Assuntos
Condensados Biomoleculares , Cromatina , Fator 3-alfa Nuclear de Hepatócito , Cromatina/genética , Montagem e Desmontagem da Cromatina , DNA , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Heterocromatina , Humanos
2.
Water Sci Technol ; 85(6): 1813-1823, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35358073

RESUMO

In this study, we investigated using the main composition of pipe deposits from water distribution networks as catalyst to activate dual-oxidant H2O2/Na2S2O8 system to produce radicals for perchloroethylene and chloramphenicol removal. According to the results, the degradation efficiency of perchloroethylene by H2O2/Na2S2O8 system was 92.05% within 8 h. Due to the slow conversion between ≡Fe3+ and ≡Fe2+, the hydroxylamine was introduced to reduce reaction time. As for the results, the degradation efficiency of chloramphenicol in the H2O2/Na2S2O8 system with hydroxylamine assistance was 73.31% within 100 min. Meanwhile, several key affecting factors and the kinetic models were investigated. The primary radicals were identified by electron paramagnetic resonance and radical scavenging tests. Eleven degradation products were confirmed by high-resolution liquid chromatography-mass spectrometry. The result of this study provided the theoretical basis for resource utilization of pipe deposits in water treatment in case of emerging contamination events.


Assuntos
Poluentes Ambientais , Compostos de Ferro , Peróxido de Hidrogênio/química , Ferro/química , Abastecimento de Água
3.
Nat Mater ; 18(9): 931-935, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31285619

RESUMO

Electric field control of spin-orbit torque in ferromagnets1 has been intensively pursued in spintronics to achieve efficient memory and computing devices with ultralow energy consumption. Compared with ferromagnets, antiferromagnets2,3 have huge potential in high-density information storage because of their ultrafast spin dynamics and vanishingly small stray field4-7. However, the manipulation of spin-orbit torque in antiferromagnets using electric fields remains elusive. Here we use ferroelastic strain from piezoelectric materials to switch the uniaxial magnetic anisotropy in antiferromagnetic Mn2Au films with an electric field of only a few kilovolts per centimetre at room temperature. Owing to the uniaxial magnetic anisotropy, we observe an asymmetric Néel spin-orbit torque8,9 in the Mn2Au, which is used to demonstrate an antiferromagnetic ratchet. The asymmetry of the Néel spin-orbit torque and the corresponding antiferromagnetic ratchet can be reversed by the electric field. Our finding sheds light on antiferromagnet-based memories with ultrahigh density and high energy efficiency.

4.
J Nanosci Nanotechnol ; 19(8): 5310-5316, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913849

RESUMO

Flexible humidity sensors play important roles in wearable devices and consuming electronics which provide a convenient way between digital and physical worlds. This work presents an easy fabricated method for flexible humidity sensors all based on carbon material including electrodes and functional layers. The interdigital electrodes are made by direct laser writing on commercial Kapton tapes and the transferring to flexible Polydimethylsiloxane (PDMS) substrates. The humidity sensing material is reduced graphene oxide (rGO) in nanometer thickness by electrospray. The rGO flakes covered the micro-size laser induced graphite (LIG), forming rGO-graphite balls, dramatically increase surface areas to interact with water molecules. The results show high precision sensitivity and fast response time for adsorption (0.9 s) and desorption (4.5 s). This method provides a novel method for fabricating cost-effective flexible humidity sensors.

5.
Anal Biochem ; 475: 40-3, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25637304

RESUMO

A method of immobilizing clenbuterol (CLEN) on the sensor chip for spectral surface plasmon resonance imaging (SPRi) was experimentally investigated. The bioprobes on the sensor chip were prepared by immobilizing bovine serum albumin (BSA) protein and conjugating CLEN molecules to BSA, which provides more active points and free orientations for specific binding. The calibration curve showed that the wavelength resonance shift decreased as the concentration of CLEN analyte increased, consistent with the inhibition principle. The limit of detection (LOD) was estimated to be 6.32 µg/ml. This method proved to be highly specific, high throughput, label free, and operationally convenient.


Assuntos
Clembuterol/análise , Sondas Moleculares/química , Soroalbumina Bovina/química , Ressonância de Plasmônio de Superfície/métodos , Animais , Bovinos
6.
Endocrine ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758293

RESUMO

PURPOSE: The current study investigated the correlation between dietary iron intake and diabetic kidney disease among diabetic adults. METHODS: This cross-sectional study enrolled 8118 participants who suffered from diabetes from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Dietary iron intake was obtained from 24 h recall interviews, and diabetic kidney disease was defined as eGFR < 60 mL/min per 1.73 m2 or albumin creatinine ratio (ACR) ≥ 30 mg/g. Three weighted logistic regression models were utilized to investigate odd ratio (OR) and 95% CIs for diabetic kidney disease. Stratified analyses were performed by gender, age, BMI, HbA1c, hypertension status, and smoking status, and diabetes types. RESULTS: Among 8118 participants (51.6% male, mean age 61.3 years), 40.7% of participants suffered from diabetic kidney disease. With the adjustment of potential covariates, we found that ≥ 12.59 mg of dietary iron was related to a lower risk of diabetic kidney disease (OR = 0.78, 95% CI: 0.63 to 0.96; OR = 0.79, 95% CI: 0.63 to 0.98). In stratified analyses, higher iron intake was negatively related to diabetic kidney disease, especially among those who were male, < 60 years, those with hypertension, those with HbA1c < 7.0%, and those who were ex-smokers. The result remained robust in sensitivity analyses. CONCLUSION: We found that ≥ 12.59 mg of dietary iron is associated with a lower risk of diabetic kidney disease, especially in those who were male, younger, heavier weight, have better blood sugar control, and those who were ex-smokers.

7.
Front Pharmacol ; 13: 967317, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36188560

RESUMO

Diabetic kidney disease (DKD) is one of the major causes of end-stage renal disease (ESRD). To evaluate the efficacy and safety of different types of mineralocorticoid receptor antagonists (MRAs) in diabetic kidney disease patients, we conducted this network meta-analysis by performing a systematic search in PubMed, MEDLINE, EMBASE, Web of Science, the Cochrane Library, and Clinicaltrials.gov. A total of 12 randomized clinical trials with 15,492 patients applying various types of MRAs covering spironolactone, eplerenone, finerenone, esaxerenone, and apararenone were included. The efficacy outcomes were the ratio of urine albumin creatine ratio (UACR) at posttreatment vs. at baseline, change in posttreatment estimated glomerular filtration (eGFR) vs. at baseline, and change in posttreatment systolic blood pressure (SBP) vs. at baseline. The safety outcome was the number of patients suffering from hyperkalemia. High-dose finerenone (MD -0.31, 95% CI: -0.52, -0.11), esaxerenone (MD -0.54, 95% CI: -0.72, -0.30), and apararenone (MD -0.63, 95% CI: -0.90, -0.35) were associated with a superior reduction in proteinuria in patients with DKD. Regarding the change in eGFR, the results of all drugs were similar, and finerenone may have potential superiority in protecting the kidney. Compared with placebo, none of the treatments was associated with a higher probability of controlling systolic blood pressure during treatment. Moreover, spironolactone, esaxerenone, and 20 mg of finerenone presented a higher risk of hyperkalemia. This Bayesian network meta-analysis was the first to explore the optimal alternative among MRAs in the treatment of DKD and revealed the superiority of 20 mg of finerenone among MRAs in treating DKD. Systematic Review Registration: PROSPERO, identifier (CRD42022313826).

8.
ACS Appl Mater Interfaces ; 13(22): 26533-26541, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34033465

RESUMO

All-solid-state batteries (ASSBs) using an alkali metal anode and a solid-state electrolyte (SE) face several problems due to poor physical and electrical contact. Recent experiments have shown that applying a stack pressure can improve the interface contact and suppress void formation. The mechanical properties of Na metal are different from those of Li metal, leading to differences in the mechanisms of the pressure-dependent interface evolution. Herein, we report a three-dimensional time-dependent model for tracking the evolution of interfaces formed between Na metal and Na-ß″-alumina SE. Our results show that Na metal contacts more conformally with the SE, providing a lower interfacial resistance, compared with Li metal, assuming equal resistance due to contamination. The differences due to contact elastoplasticity are larger than the differences in metal creep effects. In fact, we show that increased stack pressure can lead to lower creep because the contact is more conformal at high pressures. Our excellent agreement with recent experiments determines an effective hardness of Na in the Na-SE batteries to be 15 MPa. The results further reveal that the pressure dependence of void suppression is dominated by contact elastoplasticity.

9.
Sci Robot ; 6(55)2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193563

RESUMO

Agility and trajectory control are two desirable features for robotics, but they become very challenging for soft robots without rigid structures to support rapid manipulations. Here, a curved piezoelectric thin film driven at its structural resonant frequency is used as the main body of an insect-scale soft robot for its fast translational movements, and two electrostatic footpads are used for its swift rotational motions. These two schemes are simultaneously executed during operations through a simple two-wire connection arrangement. A high relative centripetal acceleration of 28 body length per square second compared with existing robots is realized on a 65-milligram tethered prototype, which is better than those of common insects, including the cockroach. The trajectory manipulation demonstration is accomplished by navigating the robot to pass through a 120-centimeter-long track in a maze within 5.6 seconds. One potential application is presented by carrying a 180-milligram on-board sensor to record a gas concentration route map and to identify the location of the leakage source. The radically simplified analog motion adjustment technique enables the scale-up construction of a 240-milligram untethered robot. Equipped with a payload of 1660 milligrams to include the control circuit, a battery, and photoresistors, the untethered prototype can follow a designated, 27.9-centimeter-long "S"-shaped path in 36.9 seconds. These results validate key performance attributes in achieving both high mobility and agility to emulate living agile insects for the advancements of soft robots.

10.
Ann Surg Oncol ; 17(11): 2976-83, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20517681

RESUMO

BACKGROUND: The aim of this study was to evaluate the prognostic value of the Jagged-1/Notch-1 expression in patients with head and neck carcinoma and to examine the possible role of the Jagged-1/Notch-1 signaling in tumorigenesis. METHODS: Immunohistochemical staining was performed on 59 formalin-fixed, paraffin-embedded head and neck carcinoma surgical specimens for Jagged-1 and Notch-1 expression. The head and neck cancer cell line, Fadu, with or without ectopic expression of the intracellular domain of Notch-1 (NICD) was also used for examining the tumorigenic capacity in vitro and in vivo. RESULTS: The study included 59 patients with a median age of 54 years (range, 35-73 years). Patients harboring tumors with both high-level Jagged-1 (J1(Hi)) and high-level Notch-1 (N1(Hi)) had a worse overall survival than the patients only with J1(Hi) or N1(Hi) as well as the patients with low-level Jagged-1 and Notch-1 (J1(Lo)/N1(Lo)) (P < 0.001). The 5-year survival rate and the median survival time were 5% and 10.9 months for J1(Hi)/N1(Hi) patients, while they were 35.04% and 47.7 months for non-J1(Hi)/Ni(Hi) patients. Ectopic expression of the active Notch-1 (NICD) in Fadu cells greatly enhanced cell migration and invasiveness in vitro and tumorigenic capacity in vivo. CONCLUSIONS: High-level coexpression of Jagged-1 and Notch-1 is associated with poor overall survival in patients with head and neck cancer. Constitutive activation of the Notch signaling, which is possibly initiated by the direct interaction between Jagged-1 and Notch-1 in head and neck cancer, confers tumor cells with a more aggressive phenotype.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Carcinoma de Células Escamosas/genética , Neoplasias de Cabeça e Pescoço/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Membrana/genética , Receptor Notch1/genética , Adulto , Idoso , Carcinoma de Células Escamosas/terapia , Linhagem Celular Tumoral , Feminino , Expressão Gênica , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Proteína Jagged-1 , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteínas Serrate-Jagged , Transdução de Sinais , Análise de Sobrevida
11.
Biosens Bioelectron ; 163: 112288, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32568695

RESUMO

Monitoring the breath information from two nostrils can detect breath-related health problems. In this work, we introduce a wearable hot-film/calorimetric breath sensing system composed of a hot-film senor in the center and two calorimetric sensors on two sides. This design has the advantages of low power consumption of 60 mW and good sensitivity to simultaneously measure the mix breath velocity and individual breath airflow signals from the two nostrils. In prototype demonstrations, abnormal breath conditions (apnea, hypopnea, polypnea) and the asymmetric breath conditions between the right and left nostril have been recorded and analyzed for potential usages in the diagnosis of specific breath-related diseases.


Assuntos
Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis
12.
ACS Appl Mater Interfaces ; 11(1): 1699-1705, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30563323

RESUMO

Laser-induced graphene (LIG) has both good electrical conductivity and three-dimensional porous structures. Here, porous graphene interdigital electrodes (IDE) were constructed as a capacitive sensor from commercial polymer films by the laser ablation process and transferred to the polydimethylsiloxane (PDMS) substrate. The graphene oxide (GO) adsorption layer was electrosprayed as a humidity sensing structure, and a Peltier device was used to control the temperature to produce the condensation of water vapors. The dew point was identified by the equilibrium state of the capacitor when the adsorption layer and the surface air reached the saturation equilibrium. The performances of the hydrophilic dew point sensing system under different environmental conditions were investigated. The results show that the precision of the carbon-based dew point sensor of ≤±0.8 °C DP with good stability and repeatability is better than those of other dew point instrument based on electrical sensing parameters at ±1.0 °C DP.

13.
Sci Robot ; 4(32)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33137774

RESUMO

Mobility and robustness are two important features for practical applications of robots. Soft robots made of polymeric materials have the potential to achieve both attributes simultaneously. Inspired by nature, this research presents soft robots based on a curved unimorph piezoelectric structure whose relative speed of 20 body lengths per second is the fastest measured among published artificial insect-scale robots. The soft robot uses several principles of animal locomotion, can carry loads, climb slopes, and has the sturdiness of cockroaches. After withstanding the weight of an adult footstep, which is about 1 million times heavier than that of the robot, the system survived and continued to move afterward. The relatively fast locomotion and robustness are attributed to the curved unimorph piezoelectric structure with large amplitude vibration, which advances beyond other methods. The design principle, driving mechanism, and operating characteristics can be further optimized and extended for improved performances, as well as used for other flexible devices.

14.
ACS Appl Mater Interfaces ; 10(31): 26357-26364, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30004667

RESUMO

High-voltage energy-storage devices are quite commonly needed for robots and dielectric elastomers. This paper presents a flexible high-voltage microsupercapacitor (MSC) with a planar in-series architecture for the first time based on laser-induced graphene. The high-voltage devices are capable of supplying output voltages ranging from a few to thousands of volts. The measured capacitances for the 1, 3, and 6 V MSCs were 60.5, 20.7, and 10.0 µF, respectively, under an applied current of 1.0 µA. After the 5000-cycle charge-discharge test, the 6 V MSC retained about 97.8% of the initial capacitance. It also was recorded that the all-solid-state 209 V MSC could achieve a high capacitance of 0.43 µF at a low applied current of 0.2 µA and a capacitance of 0.18 µF even at a high applied current of 5.0 µA. We further demonstrate the robust function of our flexible high-voltage MSCs by using them to power a piezoresistive microsensor (6 V) and a walking robot (>2000 V). Considering the simple, direct, and cost-effective fabrication method of our laser-fabricated flexible high-voltage MSCs, this work paves the way and lays the foundation for high-voltage energy-storage devices.

15.
Appl Biochem Biotechnol ; 177(6): 1327-37, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26319570

RESUMO

To prevent illegal use of clenbuterol and for quality control in the food industry, more efficient and reliable methods for clenbuterol detection are needed. In this study, clenbuterol was detected using a spectral imaging surface plasmon resonance sensor system via two inhibition methods: (1) the target site compensation method, in which anti-clenbuterol antibody was immobilized on the sensor chip as a bioprobe and (2) the solution competition method in which a clenbuterol-BSA conjugate was immobilized on the sensor chip as the bioprobe. The detectable clenbuterol concentration ranged between 6.25 and 100 µg/mL for both methods. The clenbuterol limit of detection for the target site compensation method and solution competition method are estimated to be 6.7 and 4.5 µg/mL, respectively. The proposed methods were successfully applied to the detection of clenbuterol molecules and were found to have high specificity and high-throughput and were label free and operationally convenient.


Assuntos
Anticorpos/química , Clembuterol/análise , Ressonância de Plasmônio de Superfície/métodos , Animais , Bovinos , Camundongos , Sensibilidade e Especificidade , Soroalbumina Bovina/química
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