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1.
Nano Lett ; 24(20): 6051-6060, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38682868

RESUMEN

Photoelectrochemical (PEC) cells provide a promising solution for the synthesis of hydrogen peroxide (H2O2). Herein, an integrated photocathode of p-type BiVO4 (p-BVO) array with tetragonal zircon structure coupled with different metal oxide (MOx, M = Sn, Ti, Ni, and Zn) heterostructure and NiNC cocatalyst (p-BVO/MOx/NiNC) was synthesized for the PEC oxygen reduction reaction (ORR) in production of H2O2. The p-BVO/SnO2/NiNC array achieves the production rate 65.46 µmol L-1 h-1 of H2O2 with a Faraday efficiency (FE) of 76.12%. Combined with the H2O2 generation of water oxidation from the n-type Mo-doped BiVO4 (n-Mo:BVO) photoanode, the unbiased photoelectrochemical cell composed of a p-BVO/SnO2/NiNC photocathode and n-Mo:BVO photoanode achieves a total FE of 97.67% for H2O2 generation. The large area BiVO4-based tandem cell of 3 × 3 cm2 can reach a total H2O2 production yield of 338.84 µmol L-1. This work paves the way for the rational design and fabrication of artificial photosynthetic cells for the production of liquid solar fuel.

2.
Molecules ; 28(24)2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38138530

RESUMEN

Zwitterionic polymer coatings facilitate the formation of hydration layers via electrostatic interactions on their surfaces and have demonstrated efficacy in preventing biofouling. They have emerged as a promising class of marine antifouling materials. However, designing multifunctional, environmentally friendly, and natural products-derived zwitterionic polymer coatings that simultaneously resist biofouling, inhibit protein adhesion, exhibit strong antibacterial properties, and reduce algal adhesion is a significant challenge. This study employed two diisocyanates as crosslinkers and natural urushiol and ethanolamine as raw materials. The coupling reaction of diisocyanates with hydroxyl groups was employed to synthesize urushiol-based precursors. Subsequently, sulfobetaine moieties were introduced into the urushiol-based precursors, developing two environmentally friendly and high-performance zwitterionic-functionalized polyurushiol antifouling coatings, denoted as HUDM-SB and IPUDM-SB. The sulfobetaine-functionalized polyurushiol coating exhibited significantly enhanced hydrophilicity, with the static water contact angle reduced to less than 60°, and demonstrated excellent resistance to protein adhesion. IPUDM-SB exhibited antibacterial efficacy up to 99.9% against common Gram-negative bacteria (E. coli and V. alginolyticus) and Gram-positive bacteria (S. aureus and Bacillus. sp.). HUDM-SB achieved antibacterial efficacy exceeding 95.0% against four bacterial species. Furthermore, the sulfobetaine moieties on the surfaces of the IPUDM-SB and HUDM-SB coatings effectively inhibited the growth and reproduction of algal cells by preventing microalgae adhesion. This zwitterionic-functionalized polyurushiol coating does not contain antifouling agents, making it a green, environmentally friendly, and high-performance biomaterial-based solution for marine antifouling.


Asunto(s)
Incrustaciones Biológicas , Incrustaciones Biológicas/prevención & control , Escherichia coli , Staphylococcus aureus , Polímeros/farmacología , Antibacterianos/farmacología
3.
J Environ Sci (China) ; 127: 519-529, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36522082

RESUMEN

Metal smelting have brought severe metal(loid)s contamination to the soil. Spatial distribution and pollution source analysis for soil metal(loid)s in an abandoned lead/zinc smelter were studied. The results showed that soil was contaminated heavily with metal(loid)s. The mean of lead (Pb), arsenic (As), cadmium (Cd), mercury (Hg) and antimony (Sb) content in topsoil is 9.7, 8.2, 5.0, 2.3, and 1.2 times higher than the risk screening value for soil contamination of development land of China (GB36600-2018), respectively. Cd is mainly enriched in the 0-6 m depth of site soil while As and Pb mainly deposited in the 0-4 m layer. The spatial distribution of soil metal(loid)s is significantly correlated with the pollution source in the different functional areas of smelter. As, Hg, Sb, Pb and copper (Cu) were mainly distributed in pyrometallurgical area, while Cd, thallium (Tl) and zinc (Zn) was mainly existed in both hydrometallurgical area and raw material storage area. Soil metal(loid)s pollution sources in the abandoned smelter are mainly contributed to the anthropogenic sources, accounting for 84.5%. Specifically, Pb, Tl, As, Hg, Sb and Cu mainly from atmospheric deposition (55.9%), Cd and Zn mainly from surface runoff (28.6%), While nickel (Ni) mainly comes from parent material (15.5%). The results clarified the spatial distribution and their sources in different functional areas of the smelter, providing a new thought for the risk prevention and control of metal(loid)s in polluted site soil.


Asunto(s)
Arsénico , Mercurio , Metaloides , Metales Pesados , Contaminantes del Suelo , Suelo , Zinc/análisis , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Plomo , Cadmio , Monitoreo del Ambiente/métodos , Arsénico/análisis , China , Medición de Riesgo , Metaloides/análisis
4.
Angew Chem Int Ed Engl ; 62(32): e202306420, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37264717

RESUMEN

Sluggish oxygen evolution kinetics and serious charge recombination restrict the development of photoelectrochemical (PEC) water splitting. The advancement of novel metal-organic frameworks (MOFs) catalysts bears practical significance for improving PEC water splitting performance. Herein, a MOF glass catalyst through melting glass-forming cobalt-based zeolitic imidazolate framework (Co-ag ZIF-62) was introduced on various metal oxide (MO: Fe2 O3 , WO3 and BiVO4 ) semiconductor substrates coupled with NiO hole transport layer, constructing the integrated Co-ag ZIF-62/NiO/MO photoanodes. Owing to the excellent conductivity, stability and open active sites of MOF glass, Co-ag ZIF-62/NiO/MO photoanodes exhibit a significantly enhanced photoelectrochemical water oxidation activity and stability in comparison to pristine MO photoanodes. From experimental analyses and density functional theory calculations, Co-ag ZIF-62 can effectively promote charge transfer and separation, improve carrier mobility, accelerate the kinetics of oxygen evolution reaction (OER), and thus improve PEC performance. This MOF glass not only serves as an excellent OER cocatalyst on tunable photoelectrodes, but also enables promising opportunities for PEC devices for solar energy conversion.

5.
Eur Radiol ; 32(9): 6480-6492, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35362750

RESUMEN

OBJECTIVES: To investigate if removing DCE from the Vesical Imaging Reporting and Data System (VI-RADS) influences the diagnostic accuracy of muscle-invasive bladder cancer (MIBC). We also explored using different reference standards on the MRI diagnostic performance. METHODS: We searched the Cochrane Library, Embase, and PubMed databases to June 26, 2021. Pooled biparametric MRI (bpMRI, T2WI+DWI) and multiparametric MRI (mpMRI, T2WI+DWI+DCE) sensitivities and specificities and the diagnostic performances of these methods for MIBC were compared using different reference standards. RESULTS: Seventeen studies with 2344 patients were finally included, of which 7 studies, including 1041 patients, reported the diagnostic performance of bpMRI. VI-RADS showed sensitivities and specificities of 0.91 (95% CI 0.87-0.94) and 0.86 (95% CI 0.77-0.91) at cutoff scores of 3, and 0.85 (95% CI 0.77-0.90) and 0.93 (95% CI 0.89-0.96) at cutoff scores of 4. BpMRI showed sensitivities and specificities of 0.90 (95% CI 0.69-0.97) and 0.90 (95% CI 0.81-0.95), and 0.84 (95% CI 0.78-0.88) and 0.97 (95% CI 0.87-0.99), respectively, for cutoff scores of 3 and 4. The sensitivities of bpMRI vs mpMRI for MIBC were not significantly different, but bpMRI was more specific than mpMRI at cutoff scores of 3 (p = 0.02) and 4 (p = 0.02). The VI-RADS studies using primary transurethral resection of bladder tumors (TURBT) as the reference standard had significantly higher sensitivities (p < 0.001) than those using secondary TURBT or radical cystectomy as the reference. DATA CONCLUSION: BpMRI and conventional VI-RADS had similar diagnostic efficacies for MIBC. Since MRI overestimated MIBC diagnoses using primary TURBT as the reference standard, we recommend using secondary TURBT as the reference standard. KEY POINTS: • Biparametric MRI without DCE had similar diagnostic efficacies for MIBC compared with conventional VI-RADS. • The sensitivity of VI-RADS was overestimated when referring to the primary TURBT results. • Biparametric MRI comprised of T2WI and DWI could be used for detecting MIBC in clinical practice.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Vejiga Urinaria , Sistemas de Datos , Humanos , Imagen por Resonancia Magnética/métodos , Músculos , Estudios Retrospectivos , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen
6.
Nanotechnology ; 33(38)2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35696988

RESUMEN

Geometric phase analysis (GPA) is a powerful tool to investigate the deformation in nanoscale measurement, especially in dealing with high-resolution transmission electron microscopy images. The traditional GPA method using the fast Fourier transform is built on the relationship between the displacement and the phase difference. In this paper, a nano-grid method based on real-space lattice image processing was firstly proposed to enable the measurement of nanoscale interface flatness, and the thickness of different components. Then, a hybrid method for lattice image reconstruction and deformation analysis was developed. The hybrid method enables simultaneous real-space and frequency-domain processing, thus, compensating for the shortcomings of the GPA method when measuring samples with large deformations or containing cracks while retaining its measurement accuracy.

7.
Arch Phys Med Rehabil ; 103(5): 988-997, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34461084

RESUMEN

OBJECTIVE: To evaluate the effectiveness of mirror therapy (MT) for phantom limb pain (PLP). DATA SOURCES: PubMed, EMBASE, Ovid MEDLINE, Scopus, Cochrane Library, Physiotherapy Evidence Database, CNKI, and WanFang Data were used to search for studies published up to March 31, 2021. STUDY SELECTION: Randomized controlled trials (RCTs) comparing the pain intensity of MT for PLP were performed. A total of 2094 articles were found. Among them, 10 were eligible for the final analysis. DATA EXTRACTION: The quality of the RCTs was assessed using the Physiotherapy Evidence Database (PEDro) scale by 2 independent reviewers. Outcome data were pooled according to follow-up intervals (1, 3, 6, and 12mo). Duration times were used as a basis for distinguishing subgroups. The primary evaluation was by visual analog scale. The PEDro scale was used to assess the methodological quality of studies. DATA SYNTHESIS: Meta-analysis revealed a statistically significant decrease in pain in the MT group vs the control group within 1 month (I2=0%; standardized mean difference [SMD]=-0.46, 95% confidence interval [CI], -0.79 to -0.13; P = .007). The patients with pain for longer than 1 year benefited more from MT (I2=0%; SMD=-0.46; 95% CI, -0.85 to -0.07; P = .02). CONCLUSIONS: MT has beneficial effects for patients with PLP in the short-term, as evidenced by their improved pain scores. There was no evidence that MT had a long-term effect, but that may be a product of limited data. For patients with long-term PLP, MT may be an effective treatment.


Asunto(s)
Miembro Fantasma , Humanos , Terapia del Movimiento Espejo , Dimensión del Dolor , Miembro Fantasma/terapia , Modalidades de Fisioterapia , Resultado del Tratamiento
8.
Appl Opt ; 61(2): 563-569, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35200898

RESUMEN

Interface plays an important role in determining several properties in multiphase systems. It is also essential for the accurate measurement of the interface structure in a single crystal Ni-based superalloy (SCNBS) under different conditions. In this work, a subpixel accuracy transform method is introduced in detail to measure SCNBS lattice spacing at high temperatures. An intensity ratio analysis based on a high-resolution transmission electron microscopy image is employed for SCNBS interface width analysis. In this particular sample, the interface width is about 2 nm. The evolution of the lattice spacing of an ordered γ' phase and a solid solution γ matrix is also obtained at high temperatures. The lattice misfit between the matrix γ phase and the γ' precipitation increases with the temperature, with values of -0.39% and -0.21% at 20°C and 600°C. In addition, the coefficient of the SCNBS thermal expansion at high temperatures is discussed.

9.
Aging Clin Exp Res ; 34(3): 495-503, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34313963

RESUMEN

BACKGROUND: Telomere length (TL) as a biomarker of aging was associated with many age-related diseases. The relationship between TL and osteoarthritis (OA), the most common form of joint diseases, had been investigated in a number of studies, but with the result inconsistent. AIMS: The purpose of this study was to systematically evaluate the relationship between TL and OA. METHODS: Until January 1, 2021, PubMed, Web of Science and Cochrane Library were comprehensively retrieved for relevant literatures. Quality of included literature was assessed using the Newcastle-Ottawa Scale (NOS) assessment scale. The pooled standard mean difference (SMD) with 95% confidence interval (CI) of Leukocytes TL was calculated using random-effect model. Subgroup analysis and meta-regression were used to investigate the potential source of heterogeneity. RESULTS: Six original studies containing 678 OA patients and 1457 healthy controls were included in this meta-analysis. All six included studies were case-control designed. Pooled results showed that patients with OA had a shorter TL in peripheral blood leukocytes (PBLs) compared with healthy controls, (SMD = - 0.32, 95% CI - 0.57 to - 0.06, Z = - 2.45, P = 0.014). Subgroup and meta-regression analysis showed that sex ratio and body mass index (BMI) were possible sources of heterogeneity. Publication bias was not observed. CONCLUSION: The TL of PBLs in patients with OA was shorter than that of healthy controls, suggesting that PBLs TL may be closely associated with the pathogenesis and progression of OA.


Asunto(s)
Osteoartritis , Envejecimiento , Biomarcadores , Humanos , Osteoartritis/genética , Sesgo de Publicación , Telómero
10.
Dermatol Ther ; 34(2): e14876, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33583124

RESUMEN

When congenital melanocytic nevus (CMN) is in the maxillofacial region, a safer, more effective and fewer side-effects treatment is needed for patients with high requirement for appearance. The objective of this study was to investigate the effectiveness of radiofrequency thermal ablation (RFA) for CMN in the maxillofacial region. We reviewed 21 patients treated with RFA for CMN followed by a blinded retrospective analysis of serial photographs taken during the course of their therapy. Questionnaires were used to evaluate perceived therapeutic response and complications of this treatment. Most CMNs stopped growing, faded in color and became smaller. Reduction in size of 90% to 100% was obtained in two patients (10%), 75% to 90% in six patients (29%), 50% to 75% in two patients (10%), <50% in eight patients (38%), and three had no reduction (13%). Clear effect of clinical response score was obtained in two patients (10%), excellent in four patients (19%), good in 14 patients (67%), and fair in one patient (4%). No serious complication, severe hypertrophic scarring, and evidence of recurrence was observed in any case. Percutaneous RFA, as a minimally invasive and safe treatment, may provide an alternative treatment for maxillofacial CMN.


Asunto(s)
Hipertermia Inducida , Nevo Pigmentado , Neoplasias Cutáneas , Humanos , Nevo Pigmentado/cirugía , Estudios Retrospectivos , Neoplasias Cutáneas/cirugía , Encuestas y Cuestionarios
11.
Arch Phys Med Rehabil ; 102(9): 1775-1787, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33454279

RESUMEN

OBJECTIVE: To evaluate the effectiveness of botulinum toxin A (BTX-A) in the treatment of hemiplegic shoulder pain. DATA SOURCES: PubMed, EMBASE, Elsevier, Springer, Cochrane Library, Physiotherapy Evidence Database, CNKI, and VIP were researched from the earliest records to September 1, 2020. STUDY SELECTION: Randomized controlled trials that compared shoulder BTX-A injections vs a control intervention in patients with a history of hemiplegic shoulder pain after stroke were selected. Among the 620 records screened, 9 trials with 301 eligible patients were included. DATA EXTRACTION: Outcome data were pooled according to follow-up intervals (1, 2, 4, and 12 wk). The primary evaluation indices were pain reduction (visual analog scale [VAS] score) and range of motion (ROM) improvement. The second evaluation indices were upper limb functional improvement, spasticity improvement, and incidence of adverse events. Cochrane risk-of-bias was used to assess the methodological quality of studies independently by 2 evaluators. DATA SYNTHESIS: Meta-analysis revealed a statistically significant decrease in the VAS score in the BTX group vs the control group at 1, 4, and 12 weeks postinjection (wk 1: standardized mean difference [SMD], 0.91; 95% confidence interval [CI], 0.27 to 1.54; wk 4: SMD, 1.63; 95% CI, 0.76 to 2.51; wk 12: SMD, 1.96; 95% CI, 1.44 to 2.47). Furthermore, the meta-analysis demonstrated a statistically significant increase in abduction at 1, 4, and 12 weeks postinjection (wk 1: SMD, 3.71; 95% CI, 0 to 7.41; wk 4: SMD, 8.8; 95% CI, 2.22 to 15.37; wk 12: SMD, 19.59; 95% CI, 9.05 to 30.13) and external rotation at 1, 2, 4 weeks postinjection (wk 1: SMD, 5.67; 95% CI, 0.88 to 10.47; wk 2: SMD, 9.62; 95% CI, 5.57 to 13; wk 4: SMD, 6.89; 95% CI, 2.45 to 11.33) in the BTX group. CONCLUSIONS: BTX-A injection provided greater analgesic effects and increased shoulder abduction and external rotation ROM compared with steroid or placebo injection for the treatment of HSP.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Hemiplejía/tratamiento farmacológico , Espasticidad Muscular/tratamiento farmacológico , Dolor de Hombro/tratamiento farmacológico , Humanos , Inyecciones Intramusculares , Fármacos Neuromusculares/uso terapéutico , Dimensión del Dolor , Ensayos Clínicos Controlados Aleatorios como Asunto , Rango del Movimiento Articular
12.
Appl Opt ; 59(8): 2393-2399, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32225773

RESUMEN

The geometrical phase analysis (GPA) method, which is an efficient and powerful noncontact method to obtain the strain field, has already been widely applied in deformation measurement in micro- and nano-scale. It is easy to get the strain field accurately; however, the displacement field is unreliable in some cases. Therefore, a subpixel displacement match method hereby is applied in the GPA method for the first time, to the best of our knowledge, to overcome this defect. The presented algorithm's limit error of 0.01 pixel under ideal conditions can match two corresponding local areas in reference and deformation image, and, thus, the displacement with subpixel precision of this point can be established. Owing to the continuity of the displacement field, the displacements of other points can be obtained subsequently. The error that is associated with the existing method will be dealt with in detail and verified by simulation further. Combined with simulation, the performance of the presented method is demonstrated; furthermore, the noise introduced by the imaging system is taken into consideration. Finally, a typical bending test was performed, and the result agrees well with the theoretical analysis. Both the simulation and experiment results prove that the presented method is effective and robust.

13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(2): 185-192, 2020 Mar.
Artículo en Zh | MEDLINE | ID: mdl-32220186

RESUMEN

OBJECTIVE: To investigate the effect and mechanism of static progressive stretching (SPS) in different durations on traumatic knee contracture in rats. METHODS: Seventy male Wistar rats were randomly divided into three groups, including surgical modeling group ( n=50), control group (CON, no surgery, no treatment, n=10) and trauma without immobilization group (TRA, no treatment, n=10). The knee contracture model was established, and 50 surgical modeling rats were randomly divided into five groups including static progressive stretching treatment for 20 minutes group (S20 min, n=10), treatment for 30 minutes group (S30 min, n=10), treatment for 40 minutes group (S40 min, n=10), untreatment group (UNT, no SPS, n=10) and modeling group (MOD, n=10, euthanized after immobilization for histological staining and Western blot). Individuals in the S20 min, S30 min, and S40 min groups were anesthetized and submitted to SPS. One treatment session took place every other day. A total of 8 sessions were given till the final treatment session on the day 16. On the day 0, 8, and 16 of intervention, the range of joint motion (ROM) and gait analysis were measured and compared. After the ROM measurements and gait analysis, the rats were euthanized on the day 16 and the samples were stained with HE and Masson methods. The changes of pathological organization were observed. Western blot was used to detect the expressions of transforming growth factor-ß1 (TGF-ß1) and interleukin-6 (IL-6). RESULTS: ① ROM:the ROM of S30 min group recovered similar to that of the S20 min and S40 min groups after 8 days of treatment ( P>0.05), and was the best among all the surgical modeling groups after 16 d of treatment ( P<0.05). The ROM of S20 min, S30 min and S40 min groups significantly improved on the day 8 and day 16 comparing with that on day 0 ( P<0.01). ② Gait analysis: the stands in the S30min group improved best on the day 8 and day 16 ( P<0.05) , and better than that on day 0 ( P<0.05). The stride length of the S30 min group progressed similar to that of the S40 min group on the day 8 ( P>0.05), and there was no difference among three groups on the day 16 ( P>0.05). The stride length of the S30 min group appeared to recover more quickly on the day 8 ( P<0.05), and those of S20 min and UNT groups recovered significantly on the day 16 ( P<0.05). In addition, the swings in the S30 min group improved best ( P<0.05), and it appeared to recover better on the day 16 ( P<0.05). There was no statistical difference in terms of the swing speed among the four surgical modeling groups on the day 8 ( P>0.05). The swing speed of the S30min group increased most than those of the other three groups ( P<0.05), and it was much better on the day 8 and day 16 comparing with that on the day 0 ( P<0.05 ). ③ HE and Masson staining: the fibrosis and inflammation of the S30min group were significantly suppressed comparing to the other groups on the day 16. ④ Western blot: The protein expression levels of TGF-ß1 and IL-6 were significantly lower than those in the other intervention groups including the S20 min, S40 min and UNT groups on the day 16 ( P<0.05). CONCLUSION: Static progressive stretching treatment for 30 min could significantly improve the traumatic knee contracture in rats. The mechanism may be that the SPS decreased the expressions of TGF-ß1 and IL-6, reduced the adhesion and inflammation of joint capsule. Therefore it relieved the pain and increased the joint mobility by reconstructing the structure of the capsule and suppressing the fibrotic changes.


Asunto(s)
Contractura , Articulación de la Rodilla/fisiopatología , Ejercicios de Estiramiento Muscular , Animales , Fenómenos Biomecánicos , Contractura/terapia , Interleucina-6/metabolismo , Cápsula Articular , Masculino , Rango del Movimiento Articular , Ratas , Ratas Wistar , Factor de Crecimiento Transformador beta1/metabolismo
14.
BMC Genomics ; 20(1): 573, 2019 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-31296162

RESUMEN

BACKGROUND: The genome of Banana bunchy top virus (BBTV) consists of at least six circular, single-stranded DNA components of ~ 1 kb in length. Some BBTV isolates may also carry satellite DNA molecules that are not essential for BBTV infection. The relation between multipartite DNA virus replication and their transcriptional levels and the underlying mechanism remain unclear. RESULTS: To understand the coordinated replication and transcription of the multiple genomic components, the absolute amounts of each BBTV DNA component were measured by real-time PCR (qPCR), and their transcriptional levels were determined by RNAseq and reverse transcription-qPCR (qRT-PCR). Significant differences were found in the absolute amounts of individual BBTV genomic components. Transcriptional levels of each BBTV genomic component obtained from the RNAseq data matched closely to those obtained from qRT-PCR, but did not correspond to the absolute amount of each DNA component. The ratio of transcript over DNA copies ranged from 46.21 to 1059.44%, which was possibly regulated by the promoter region in the intergenic region of each component. To further determine this speculation, the promoter region of the DNA-S, -M or -N was constructed to the upstream of green fluorescent protein (GFP) gene for transient expression by agrobacterium-mediated transformation method. The qRT-PCR showed the highest transcriptional activity was promoted by DNA-N promoter, about 386.58% activity comparing with CaMV 35S promoter. Confocal microscopy observation showed that the intensity of green fluorescence was corresponding to that of qRT-PCR. CONCLUSIONS: Our data clearly showed that BBTV was able to control the transcriptional level of each DNA component independently by through the promoter sequences in the intergenic region. Moreover, a cis-acting element from DNA-N component had a high transcriptional activity.


Asunto(s)
Babuvirus/genética , Genómica , Elementos Reguladores de la Transcripción/genética , Transcripción Genética , Genoma Viral/genética , ARN Mensajero/genética , Análisis de Secuencia de ARN
15.
Opt Express ; 27(24): 34626-34638, 2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-31878650

RESUMEN

Camera calibration is an important part of high-precision optical measurement, which is especially difficult in the micro-nano field. Based on the integrated correlation calculation and CCD moiré method, this paper describes the development of a lens calibration technique called the Integrated Colour CCD Moiré Method (ICCM). The CCD moiré fringes, formed by superimposing a periodic optical signal of a specimen grating with a CCD target array or a Bayer filter array, significantly enlarges the deformation modulated by lens distortion and the calibration plate attitude (i.e. the rotation angle relative to the camera coordinate system). To measure lens distortion using CCD moiré, the deformation pattern that is governed by the lens distortion, specimen grating attitude and carrier was used to construct a CCD fringe image. If the constructed CCD fringe image based on the trial lens distortion and rotation angles have a maximum similarity to the captured CCD moiré image, the lens distortion and rotation angles are correctly inversed. Particle swarm optimisation algorithm was selected to search for the true value so that the accuracy and robustness could be improved. Numerical experiments verified that the ICCM method developed in this work can simultaneously inverse the lens distortion, rotation angle and the grating pitch with high precision. The lens distortion of the metallographic microscope has been successfully characterised by the developed method with an 833 nm pitch grating. Simulations and experiments showed that ICCM is an intuitive, accurate, anti-noise and robust distortion calibration method.

16.
Opt Express ; 25(25): 31789-31800, 2017 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-29245848

RESUMEN

Interface disbond in thermal barrier coatings (TBCs) is one of the key issues that cause their premature failure. In general, blind hole defects are often used as substitutes in transient thermography. The linear laser fast scanning thermography (LLFST) method was developed in this study and combined with several post-processing algorithms to accurately detect blind hole defects in TBCs. Through numerical simulation and experimental verification, a unique thermal response characteristic of blind holes in the cooling phase, namely a distinct "tailing" phenomenon, was summarized and utilized to recognize small defects. Validation tests indicated that blind holes with diameters of 1, 2, and 3 mm and artificial disbonds with diameters of 2 and 3 mm in TBCs are detected with high efficiency.

17.
Reprod Biol Endocrinol ; 15(1): 86, 2017 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-29065928

RESUMEN

BACKGROUND: Proper expression of key reproductive hormones from gonadotrope cells of the pituitary is required for pubertal onset and reproduction. To further our understanding of the molecular events taking place during embryonic development, leading to expression of the glycoproteins luteinizing hormone (LH) and follicle-stimulating hormone (FSH), we characterized chromatin structure changes, imparted mainly by histone modifications, in model gonadotrope cell lines. METHODS: We evaluated chromatin status and gene expression profiles by chromatin immunoprecipitation assays, DNase sensitivity assay, and RNA sequencing in three developmentally staged gonadotrope cell lines, αT1-1 (progenitor, expressing Cga), αT3-1 (immature, expressing Cga and Gnrhr), and LßT2 (mature, expressing Cga, Gnrhr, Lhb, and Fshb), to assess changes in chromatin status and transcription factor access of gonadotrope-specific genes. RESULTS: We found the common mRNA α-subunit of LH and FSH, called Cga, to have an open chromatin conformation in all three cell lines. In contrast, chromatin status of Gnrhr is open only in αT3-1 and LßT2 cells. Lhb begins to open in LßT2 cells and was further opened by activin treatment. Histone H3 modifications associated with active chromatin were high on Gnrhr in αT3-1 and LßT2, and Lhb in LßT2 cells, while H3 modifications associated with repressed chromatin were low on Gnrhr, Lhb, and Fshb in LßT2 cells. Finally, chromatin status correlates with the progressive access of LHX3 to Cga and Gnrhr, followed by PITX1 binding to the Lhb promoter. CONCLUSION: Our data show the gonadotrope-specific genes Cga, Gnrhr, Lhb, and Fshb are not only controlled by developmental transcription factors, but also by epigenetic mechanisms that include the modulation of chromatin structure, and histone modifications.


Asunto(s)
Cromatina/metabolismo , Gonadotrofos/metabolismo , Gonadotropinas/genética , Regiones Promotoras Genéticas , Factores de Transcripción/metabolismo , Animales , Línea Celular , Epigénesis Genética , Regulación del Desarrollo de la Expresión Génica , Gonadotropinas/metabolismo , Ratones , Células 3T3 NIH , Unión Proteica , Transcripción Genética
18.
Biotechnol Lett ; 38(6): 919-29, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26892225

RESUMEN

OBJECTIVES: To identify the best lipid nanoparticles for delivery of purified Cas9 protein and gRNA complexes (Cas9 RNPs) into mammalian cells and to establish the optimal conditions for transfection. RESULTS: Using a systematic approach, we screened 60 transfection reagents using six commonly-used mammalian cell lines and identified a novel transfection reagent (named Lipofectamine CRISPRMAX). Based on statistical analysis, the genome modification efficiencies in Lipofectamine CRISPRMAX-transfected cell lines were 40 or 15 % higher than those in Lipofectamine 3000 or RNAiMAX-transfected cell lines, respectively. Upon optimization of transfection conditions, we observed 85, 75 or 55 % genome editing efficiencies in HEK293FT cells, mouse ES cells, or human iPSCs, respectively. Furthermore, we were able to co-deliver donor DNA with Cas9 RNPs into a disrupted EmGFP stable cell line, resulting in the generation of up to 17 % EmGFP-positive cells. CONCLUSION: Lipofectamine CRISPRMAX was characterized as the best lipid nanoparticles for the delivery of Cas9 RNPs into a variety of mammalian cell lines, including mouse ES cells and iPSCs.


Asunto(s)
Lípidos , Transfección/métodos , Animales , Sistemas CRISPR-Cas , Línea Celular , Electroporación , Edición Génica/métodos , Marcación de Gen/métodos , Proteínas Fluorescentes Verdes/genética , Humanos , Células Madre Pluripotentes Inducidas , Lípidos/toxicidad , Ratones
19.
Appl Opt ; 54(26): 7842-50, 2015 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-26368953

RESUMEN

By using the principle of stereovision, 3D digital image correlation (3D-DIC) can determine the 3D morphology and deformation of a target and has been widely used in experimental mechanics as a noncontact 3D measurement technique. To eliminate the limitations of the conventional 3D-DIC system, this study proposes a calibration-free single-lens 3D-DIC system based on a bilateral telecentric lens and a bi-prism. The performance of the proposed system is verified by tests of rigid-body translation along the out-of-plane direction. As a comparison, the same rigid-body translations are measured using a single-entocentric-lens 3D-DIC system. The results show that the measurement accuracy of the proposed system is higher than that of the entocentric-lens-based one. As an application, the proposed system is used to measure the thermal linear expansion of a ceramic plate at elevated temperatures. The reasonable measurement results verify its applicability in deformation measurements, even in high-temperature environments.

20.
Appl Opt ; 54(6): 1290-301, 2015 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-25968190

RESUMEN

Digital image correlation (DIC) is an effective and popular tool for displacement and strain measurements. In the standard subset-based algorithms, the center point of a subset is considered by default as the control point for calculation, and it is difficult to obtain the deformation information at the boundary. Proper selection of the subset shape and the location of control points are vital to the displacement calculation at the boundary. In this paper, registration accuracies of several typical types of subset shapes and different locations of control points are investigated. The results illustrate that different choices of subset shapes can greatly affect the registration accuracy, while different choices for the locations of control points have little impact on it. Based on these results, the noncentral algorithm is developed for the whole-field deformation measurement.

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