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1.
Blood ; 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32384137

RESUMO

Erythropoiesis is a complex multistage process that involves differentiation of early erythroid progenitors to enucleated mature red blood cells, in which lineage-specific transcription factors play essential roles. Erythroid Krüppel-like factor (EKLF/KLF1) is a pleiotropic erythroid transcription factor that is required for the proper maturation of the erythroid cells, whose expression and activation are tightly controlled in a temporal and differentiation stage-specific manner. Here, we uncover a novel role of G protein pathway suppressor 2 (GPS2), a subunit of the NCoR/SMRT nuclear receptor corepressor complex, in erythrocyte differentiation. Our study demonstrates that knockdown of GPS2 significantly suppresses erythroid differentiation of human CD34+ cells cultured in vitro and xenotransplanted in NOD/SCID/IL2RÎ³null (NSG) mice. Moreover, global deletion of GPS2 in mice causes impaired erythropoiesis in the fetal liver and leads to severe anemia. Flow cytometric analysis and Wright-Giemsa staining show a defective differentiation at late stages of erythropoiesis in Gps2-/- embryos. Mechanistically, GPS2 interacts with EKLF and prevents proteasome-mediated degradation of EKLF, thereby increases EKLF stability and transcriptional activity. Moreover, we identify the amino acids 191-230 region in EKLF protein, responsible for GPS2 binding, that is highly conserved in mammals and essential for EKLF protein stability. Collectively, our study uncovers a previously unknown role of GPS2 as a post-translational regulator which enhances the stability of EKLF protein and thereby promotes erythroid differentiation.

2.
Life Sci ; 253: 117675, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32360621

RESUMO

AIMS: Gliomas are responsible for the majority of deaths from primary brain tumours. Sevoflurane showed inhibition effects on the tumor progression in vitro. However, whether sevoflurane could affect the stemness of glioma stem cells (GSCs) and the potential molecular mechanism have not been well elucidated. MAIN METHODS: Effects of sevoflurane on cell viability, proliferation and invasion ability of glioma cells as well as tumor growth in vivo were assessed. Sphere formation assay was performed to evaluate the effect of sevoflurane on the stemness of GSCs. Effects of sevoflurane on mitochondrial function was evaluated by intracellular/mitochondrial reactive oxygen species (ROS) level and mitochondrial membrane potential. Expression levels of proliferation-related proteins, stemness markers and proteins in CaMKII/JNK cascade were measured by Western blot. KEY FINDINGS: Sevoflurane inhibited the viability, proliferation and invasion ability of glioma cells (U87MG and U373MG). Western blot showed that sevoflurane decreased the expression levels of proliferation and invasion-related proteins. Sphere formation ability of GSCs, expression levels of stemness markers and mitochondrial function were significantly suppressed by sevoflurane. Moreover, sevoflurane treatment significantly increased the Ca2+ concentration and stimulated phosphorylation of CaMKII, JNK and IRS1. Ca2+ chelator BAPTA-AM combined with sevoflurane synergistically inhibited colony forming ability and the expression levels of proliferation-related proteins and stemness markers. In addition, the in vivo study further confirmed that sevoflurane inhibited tumor growth via Ca2+-dependent CaMKII/JNK cascade. SIGNIFICANCE: The present study demonstrated that sevoflurane inhibited glioma tumorigenesis and modulated the cancer stem cell-like properties and mitochondrial membrane potential via activation of Ca2+-dependent CaMKII/JNK cascade.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32333194

RESUMO

Transaminase responsible for alienating prochiral ketone compound is applicable to asymmetric synthesis of herbicide L-phosphinothricin (L-PPT). In this work, the covalent immobilization of recombinant transaminase from Citrobacter koseri (CkTA) was investigated on different epoxy resins. Using optimum ES-105 support, a higher immobilized activity was obtained via optimizing immobilization process in terms of enzyme loading, coupling time and initial PLP concentration. Crucially, due to blocking unreacted epoxy groups on support surface with amino acids, the reaction temperature of blocked immobilized biocatalyst was enhanced from 37 to 57 °C. Its thermostability at 57 °C was also found to be superior to that of free CkTA. The Km value was shifted from 36.75 mM of free CkTA to 39.87 mM of blocked immobilized biocatalyst, demonstrating that the affinity of enzyme to the substrate has not been apparently altered. Accordingly, the biocatalyst performed the consecutive synthesis of L-PPT for 11 cycles (yields>91%) with retaining more than 91.13% of the initial activity. The seemingly the highest reusability demonstrates this biocatalyst has prospective for reducing the costs of consecutive synthesis of L-PPT with high conversion.

4.
J Phys Condens Matter ; 32(33): 335803, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32294629

RESUMO

Multiferroic materials endowed with both dielectric and magnetic orders, are ideal candidates for a wide range of applications. In this work, we reported two phase transitions of MnI2 at 3.45 K and 4 K by systemically measuring the magnetic-field and temperature-dependent magnetization of the MnI2 thin flakes. Furthermore, we observed similar temperature and field-dependent behaviours for the magnetic susceptibility of MnI2 and electronic capacitance of the Ag/MnI2/Ag devices below 3.5 K. Considering the related theory work, we discussed the relationship between the antiferromagnetic and ferroelectric orders in MnI2. Our work reveals the in-plane magnetic and electric properties of MnI2 materials, which might be helpful for the further investigation and application of MnI2 multiferroics in the future.

5.
Photodiagnosis Photodyn Ther ; : 101761, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32283311

RESUMO

Xeroderma pigmentosum (XP) is a rare autosomal recessive dermatosis that is often complicated by multiple skin tumours at exposed locations, which are difficult to treat. We report a case of a 12-year-old girl with XP treated with oral retinoic acid and photodynamic therapy (PDT) with good clinical results. She had an 8-year history of multiple skin lesions that first appeared on her nasal dorsum, but gradually increased in size and spread to her entire face, neck, and upper limbs. Notably, the lesions became evidently aggravated after sun exposure. When she was 6 years old, sesame-seed-sized papules and plaques appeared, which were fragile and irregular in shape and would self-rupture, accompanied with slight itchiness and bloody exudate. Examination revealed multiple basal cell carcinomas. The tumours were treated with local carbon dioxide laser therapy combined with PDT. On the follow-up visit 2 months after the surgery, most of the skin lesions on her face had subsided. In cases of multiple tumours, PDT can be the treatment method of choice because it is less invasive, has less side effects, and does not damage the surrounding normal tissues.

6.
Trends Cancer ; 2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32291236

RESUMO

Sperm-associated Antigen 5 (SPAG5) is a mitotic spindle protein. Recent studies have found that it is overexpressed in many human cancers and functions as an oncogene. Here, we summarize the current underlying mechanisms for its oncogenic roles in regulating cellular behaviors of cancer cells and discuss the possibility of targeting SPAG5 for cancer treatment.

7.
Zhongguo Zhen Jiu ; 40(3): 337-41, 2020 Mar 12.
Artigo em Chinês | MEDLINE | ID: mdl-32270653

RESUMO

There is no criteria of placebo acupuncture method and no suitable method for all kinds of acupuncture research currently. In this paper, the methods and theories of placebo acupuncture were collected in recent 10 years at home and abroad. The analysis was conducted in the aspects of the premise of placebo acupuncture design, the common methods and their advantages and disadvantages, the application of various placebo acupuncture methods and the controversy on placebo acupuncture. It is required to further improve the design of placebo acupuncture control, explore the key questions of it and specify the criteria of its method so as to lay the foundation for the establishment of scientific and rational placebo acupuncture control in acupuncture research.

8.
J Clin Nurs ; 2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32279372

RESUMO

9.
Am J Orthod Dentofacial Orthop ; 157(3): 329-339, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32115111

RESUMO

INTRODUCTION: The purpose of this study was to comparatively evaluate the effects of Twin-block (TB) appliance and sagittal-guidance Twin-block (SGTB) appliance on alveolar bone around mandibular incisors in growing patients with Class II Division 1 malocclusion, using cone-beam computed tomography. METHODS: The sample consisted of 25 growing patients with Class II Division 1 malocclusion (14 boys and 11 girls, mean age 11.92 ± 1.62 years) and was randomly distributed into the TB group (n = 13) and the SGTB group (n = 12). The treatment duration was 11.56 ± 1.73 months. Pretreatment (T1) and posttreatment (T2) cone-beam computed tomography scans were taken in both groups. Height, thickness at apex level, and volume of the alveolar bone around mandibular left central incisors were measured respectively on labial and lingual side, using Mimics software (version 19.0; Materialise, Leuven, Belgium). Based on the stable structures, 3-dimensional (3D) registrations of T1 and T2 models were taken to measure the sagittal displacement of incisors. Intragroup comparisons were evaluated by paired-samples t tests and Wilcoxon tests. Independent-samples t tests and Mann-Whitney U tests were used for intergroup comparisons. RESULTS: In both groups, alveolar bone height and volume on the labial side of the incisors significantly decreased after treatment (P <0.05). Lingual alveolar bone height, lingual and total alveolar bone volume, labial, lingual and total alveolar bone thickness showed no significant difference between T1 and T2 (P >0.05). In both groups the incisors tipped labially and drifted to the labial side. Compared with the TB group, less labial alveolar bone loss, less incisor proclination and crown edge drift were found in the SGTB group (P <0.05). CONCLUSIONS: Labial alveolar bone loss around mandibular incisors was observed after both types of appliances treatment in growing patients with Class II Division 1 malocclusion. Less labial alveolar bone loss, less incisor proclination, and crown edge drift were found in the SGTB group than in the TB group during treatment.

Assuntos
Perda do Osso Alveolar , Má Oclusão de Angle Classe II , Aparelhos Ortodônticos , Adolescente , Cefalometria , Criança , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Incisivo , Masculino , Má Oclusão de Angle Classe II/diagnóstico por imagem , Má Oclusão de Angle Classe II/terapia , Mandíbula , Coroa do Dente
10.
Iran J Kidney Dis ; 14(2): 107-118, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32165595

RESUMO

INTRODUCTION: Previous studies have shown that TGF-ß1/Smad3 signaling promotes renal fibrosis by inhibiting miR-29. To date, only few studies have reportedon circulating microRNAs in IgA nephropathy (IgAN). However, the plasma expression of miR-29a and its role in patients with IgAN remains unclear. In this study, we attempted to elucidate whether plasma miR-29a expression can be used as a biomarker for monitoring disease states. METHODS: For this study, 15 healthy subjects, 36 patients with untreated renal biopsy-proven IgAN, and 79 patients with IgAN, who were under treatment for a period of 1 year on an average, all of whom had similar age and gender distributions, were included. The plasma expression of miR-29a in each group was explored by real-time PCR, and the relationship between miR-29a expression and clinical, pathological, and prognostic indicators of IgAN was further evaluated. RESULTS: Relative plasma expression of miR-29a in patients with IgAN was significantly lower than that in healthy controls (P < .001), and these changes in plasma miR-29a could be suppressed by treatment (P < .05). Plasma miR-29a was positively correlated with eGFR and negatively correlated with proteinuria and serum creatinine, irrespective of whether or not the patients with IgAN accepted treatment (P < .05). Plasma miR-29a level was negatively correlated with primary pathological parameters such as crescent formation, Lee's and Oxford classification (P < .05). Kaplan-Meier analysis revealed that patients with high plasma expression of miR-29a had better renal function and better response to treatment compared to those with low expression (P < .05). CONCLUSION: Plasma miR-29a could be considered as a biological marker that reflects renal damage and function, to predict the progression of IgAN.

11.
ACS Sens ; 5(4): 994-1001, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32174111

RESUMO

Although volatile organic compound samples can be detected by gas nanosensors in adsorption principles, extreme concentrations of target gases imply the excessive adsorption, which would lead to a long recovery time and even a shortened lifetime. Herein, we report the observations of the ionization current sensing behavior on the volatile organic compounds in an ionization gas sensor with silicon-based nanostructures. The micro ionization gas sensor consists of a pair of silicon microneedle array electrodes covered by nanolayer structures and a microdischarge gas gap. The dynamic response behaviors of the sensors to the exposure of ethanol, acetone, and 2-chloroethyl ethyl sulfide have been carefully scrutinized. The sensor exhibits sound performances to the high-concentration volatile organic compounds with a fast-recovery property and could generate effective responses well at 36 V, namely, the safety operation voltages. It could be well understood by the Jesse effect where small proportion of impurities in gases could lead to an intensive increase in the overall ionization probability. Besides, the reproducibility, recovery time, sensitivity, and selectivity properties have been systematically characterized.

12.
Int J Biol Macromol ; 154: 878-887, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32173428

RESUMO

A series of agar/κ-carrageenan mixed hydrogels with different mass ratios were prepared, and their physicochemical properties, gelling behavior and drug release performance were determined and analyzed. The results showed that the gel strength, the gelling temperature and the gel melting temperature decreased with the increase of κ-carrageenan, while the apparent viscosities increased. Optical rotation and differential scanning calorimetry (DSC) indicated that there did exist intermolecular interactions between agar and κ-carrageenan, and the detailed gelling mechanism of the mixed hydrogels was proposed, which was different from that of the previous research. Besides, agar/κ-carrageenan mixed hydrogels were used as carriers for the delivery of metformin hydrochloride (MET). The results showed that the drug loading efficiency and the sustained release capacity of agar hydrogels could be enhanced by the addition of κ-carrageenan, and the release profile was mainly dominated by the electrostatic interaction between the MET and the polysaccharides. These results indicated that κ-carrageenan had the potential to improve the physicochemical properties and drug release performance of agar hydrogel.

13.
J Int Med Res ; 48(3): 300060519889458, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32216522
14.
Sci Adv ; 6(12): eaaz3367, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32206724

RESUMO

Mammalian transient receptor potential (TRP) channels are major components of Ca2+ signaling pathways and control a diversity of physiological functions. Here, we report a specific role for TRPC1 in the entry of herpes simplex virus type 1 (HSV-1) into cells. HSV-1-induced Ca2+ release and entry were dependent on Orai1, STIM1, and TRPC1. Inhibition of Ca2+ entry or knockdown of these proteins attenuated viral entry and infection. HSV-1 glycoprotein D interacted with the third ectodomain of TRPC1, and this interaction facilitated viral entry. Knockout of TRPC1 attenuated HSV-1-induced ocular abnormality and morbidity in vivo in TRPC1-/- mice. There was a strong correlation between HSV-1 infection and plasma membrane localization of TRPC1 in epithelial cells within oral lesions in buccal biopsies from HSV-1-infected patients. Together, our findings demonstrate a critical role for TRPC1 in HSV-1 infection and suggest the channel as a potential target for anti-HSV therapy.

15.
Opt Lett ; 45(4): 1009-1012, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32058528

RESUMO

We experimentally and numerically demonstrated the generation of a (3, 1) vector signal by a single Mach-Zehnder modulator (MZM) without pre-coding. The MZM is driven by the (3, 1) modulated signal after photoelectric conversion by the "square law" of a photodetector. Although the phase changes, the corresponding constellation distribution is consistent with that of the regular signal. Our proposed scheme effectively avoids the pre-coding process with a simple architecture. The bit-error-ratio (BER) results indicate that the (3, 1) signal has a better BER performance than the pre-coded quadrature phase shift keying vector signal, and both are below ${3.8}\times {{10}^{ - 3}}$3.8×10-3 after 25 km optical fiber transmission.

16.
Food Funct ; 11(2): 1754-1763, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32043502

RESUMO

Carvacryl acetate (CA) is a semisynthetic monoterpenic ester obtained from essential oils, and it exerts an antioxidation effect. The purpose of our study was to investigate whether CA could provide neuroprotection against oxidative stress caused by cerebral ischemia-reperfusion injury (CIRI) and elucidate the underlying mechanism. Middle cerebral artery occlusion (MCAO)-induced damage was established in Sprague Dawley (SD) rats and PC12 cells were exposed to hydrogen peroxide (H2O2) to imitate oxidative stress damage. TTC, HE and Nissl staining were used to observe the pathological morphology of lesions. The contents of ROS and MDA, and the activity of SOD were measured to reflect the level of oxidative stress. In addition, the TUNEL method was used to assess injuries in vitro, and the expression of Nrf2 was determined by immunohistochemical staining and western blot analysis. Importantly, we constructed and validated Nrf2 knockdown PC12 cells to confirm the key role of Nrf2 in the neuroprotective effect of CA against oxidative stress injuries. CA alleviated CIRI in rats with MCAO, as shown by brain tissue pathophysiology. The contents of ROS and MDA were reduced, and the SOD activity was augmented by the simultaneous promotion of Nrf2 expression. In addition, the H2O2-induced injury in Nrf2-knockdown PC12 cells was more serious than it was in control cells, and CA-mediated neuroprotection was exclusively inhibited by the knock down of Nrf2 in PC12 cells. In conclusion, it is shown here that CA has the effect of relieving cerebral ischemia reperfusion-induced oxidative stress injury via the Nrf2 signalling pathway.

17.
Medicine (Baltimore) ; 99(3): e18800, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32011484

RESUMO

RATIONALE: Low-grade malignant fibrous myxoid sarcoma (LGFMS) is a malignant tumor that originates from soft tissues and has specific clinical and histopathological characteristics. Paravertebral LGFMS is rarely reported. PATIENT CONCERNS: A 60-year-old woman had pain in the lower back and right anterior thigh for more than 3 years. DIAGNOSIS: Paravertebral LGFMS. INTERVENTIONS: Tumor resection, vertebral canal decompression and pedicle screw fixation. OUTCOMES: The tumor was excised, and the vertebral arch was fixed with pedicle screws at the root. Chemoradiotherapy was not performed. Her postoperative visual analogue scale (VAS) score decreased from 7 points at admission to 2 points at follow-up. The patient was discharged at postoperative day 13, and no recurrence was observed at the 6-month follow-up. LESSONS: Although LGFMS is rare, it should be considered in differential diagnosis of other soft tissue tumors to avoid misdiagnosis and inappropriate treatment.

Assuntos
Sarcoma/diagnóstico , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/diagnóstico , Neoplasias de Tecidos Moles/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Sarcoma/complicações , Neoplasias de Tecidos Moles/complicações , Compressão da Medula Espinal/diagnóstico , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/cirurgia , Coluna Vertebral
18.
Int J Biol Macromol ; 148: 777-784, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31978475

RESUMO

The wounds of diabetic patients are difficult to heal, which could lead to a limb amputation or even death. The experiment aims to develop a new type of nanoparticles that could accelerate wound healing. Epigallocatechin gallate, ascorbic acid, gelatin and chitosan nanoparticles (EV NPS) were prepared by ion cross-linking method, and their properties were studied. The optimal formula ratio of EV NPS is Vc:EGCG:Gel:CS = 0.2:3:1:1. Transmission electron microscope (TEM) images show that it is a roughly uniform spherical nanoparticle with a diameter of 200 nm. ICR mice were intraperitoneally injected with streptozocin (STZ) to establish diabetic mice. Full-thickness excisional wounds were established on the back of mice. The results showed that EV NPS can promote wound healing in diabetic mice, and the mechanism may be through increasing collagen accumulation, promoting angiogenesis and reducing the infiltration of inflammatory cells. EV NPS may have potential application values for wound healing in diabetic mice.

19.
J Nurs Manag ; 28(3): 559-566, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31954085

RESUMO

AIM: To analyse the structural associations among job characteristics, organizational justice, work engagement and nursing care quality in Chinese nurses. BACKGROUND: Nursing care quality helps ensure patient safety, which are core concerns. The explicit relationships among the study's variables from a management perspective can help hospital managers to implement effective strategies to improve nursing care quality. METHODS: This cross-sectional study was conducted to investigate the relationships among the variables in 1,615 nurses in eight Chinese tertiary hospitals. Structural equation modelling was used to test a proposed model of these relationships. RESULTS: The scores of job characteristics, organizational justice, work engagement and nursing care quality were 3.55 ± 0.41, 3.84 ± 0.77, 4.67 ± 1.30 and 3.42 ± 0.70. Job characteristics and organizational justice had direct effects on nursing care quality. Work engagement mediated the relationship of nursing care quality with job characteristics and organizational justice. The final model explained 24% of nursing care quality. CONCLUSION: The results provide a better understanding of the associations between the study's variables. Perceived job characteristics and organizational justice can improve nursing care quality through work engagement. IMPLICATIONS FOR NURSING MANAGEMENT: Reconfiguring work design to strengthen nurses' positive perceptions of job characteristics and organizational justice can enhance nursing care quality.

20.
ACS Appl Mater Interfaces ; 12(5): 6460-6470, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31942793

RESUMO

Light-driven actuators that directly convert light into mechanical work have attracted significant attention due to their wireless advantage and ability to be easily controlled. However, a fundamental impediment to their application is that the continuous motion of light-driven flexible actuators usually requires a periodically switching light source or the coordination of other additional hardware. Here, for the first time, continuous flapping-wing motion under sunlight is realized through the utilization of a simple nanocrystalline metal polymer bilayer structure without the coordination of additional hardware. The light-driven performance can be controlled by adjusting the grain size of the upper nanocrystalline metallic layer or selecting metals with different thermodynamic parameters. The achieved highest frequency of flapping-wing motion is 4.49 Hz, which exceeds the frequency of real butterfly wings, thus informing the further development of sunlight-driven bionic flying animal robotics without external energy consumption. The flapping-wing motion has been used to realize a light-driven whirligig, a light-driven sailboat, and photoelectric energy harvesting. Furthermore, the flexible bilayer actuator features the ability to be driven by light and electricity, low-power actuation, a large deflection, fast actuation speed, long-time stability, strong design ability, and large-area facile fabrication. The bilayer film considered herein represents a simple, general, and effective strategy for preparing photoelectric-driven flexible actuators with target performances and informs the standardization and industrial application of flexible actuators in the future.