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Preeclampsia (PE) is a life-threatening pregnancy-specific complication with controversial mechanisms and no effective treatment except delivery is available. Currently, increasing researchers suggested that PE shares pathophysiologic features with protein misfolding/aggregation disorders, such as Alzheimer disease (AD). Evidences have proposed defective autophagy as a potential source of protein aggregation in PE. Endoplasmic reticulum-selective autophagy (ER-phagy) plays a critical role in clearing misfolded proteins and maintaining ER homeostasis. However, its roles in the molecular pathology of PE remain unclear. We found that lncRNA DUXAP8 was upregulated in preeclamptic placentae and significantly correlated with clinical indicators. DUXAP8 specifically binds to PCBP2 and inhibits its ubiquitination-mediated degradation, and decreased levels of PCBP2 reversed the activation effect of DUXAP8 overexpression on AKT/mTOR signaling pathway. Function experiments showed that DUXAP8 overexpression inhibited trophoblastic proliferation, migration, and invasion of HTR-8/SVneo and JAR cells. Moreover, pathological accumulation of swollen and lytic ER (endoplasmic reticulum) was observed in DUXAP8-overexpressed HTR8/SVneo cells and PE placental villus trophoblast cells, which suggesting that ER clearance ability is impaired. Further studies found that DUXAP8 overexpression impaired ER-phagy and caused protein aggregation medicated by reduced FAM134B and LC3II expression (key proteins involved in ER-phagy) via activating AKT/mTOR signaling pathway. The increased level of FAM134B significantly reversed the inhibitory effect of DUXAP8 overexpression on the proliferation, migration, and invasion of trophoblasts. In vivo, DUXAP8 overexpression through tail vein injection of adenovirus induced PE-like phenotypes in pregnant rats accompanied with activated AKT/mTOR signaling, decreased expression of FAM134B and LC3-II proteins and increased protein aggregation in placental tissues. Our study reveals the important role of lncRNA DUXAP8 in regulating trophoblast biological behaviors through FAM134B-mediated ER-phagy, providing a new theoretical basis for understanding the pathogenesis of PE.
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Autofagia , Retículo Endoplasmático , Pré-Eclâmpsia , Proteínas Proto-Oncogênicas c-akt , RNA Longo não Codificante , Transdução de Sinais , Serina-Treonina Quinases TOR , Trofoblastos , Adulto , Animais , Feminino , Humanos , Gravidez , Ratos , Autofagia/genética , Linhagem Celular , Movimento Celular/genética , Proliferação de Células/genética , Retículo Endoplasmático/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Serina-Treonina Quinases TOR/metabolismo , Trofoblastos/metabolismo , Trofoblastos/patologia , MasculinoRESUMO
Purpose: Intradiscal biacuplasty (IDB) has been proven to be effective for treating lumbar degenerative disc disease (DDD). However, there has not been a reported prognostic factor for IDB. The present study meticulously evaluates the general and radiographic features that may serve as markers for predicting the therapeutic outcome of IDB. Methods: A prospective case series study was conducted, following time-series analysis moving averages models, with forty-one patients suffering from chronic discogenic lower back pain for more than six months. These patients subsequently received lumbar cool radiofrequency IDB and were enrolled in the study. Thirty-seven patients completed follow-up questionnaires at 1, 3, 6, and 12 months. The surgical outcomes were reported using visual analogue scale (VAS), Oswestry disability index (ODI), and the consumption of nonsteroidal anti-inflammatory drugs (NSAID). Furthermore, a univariate analysis was performed to identify prognostic factors associated with pain relief from age, gender, body mass index (BMI), and pre-operative lumbar magnetic resonance imaging reading. Results: Significant reductions were found in estimated VAS and ODI at the post-operative period at 1, 3, 6, and 12 months (P < 0.001). The NSAID dosage was significantly decreased at 3-month and 1-year follow-up (P < 0.05). No procedure-related complications were detected. The prognosis of IDB was not related to disc height, Pfirrmann grading or Modic endplate change. However, disc extrusions were associated with promising outcomes (VAS improvement ≥ 50%) on pain relief (P < 0.05). Conclusion: IDB is a good alternative choice for treating lumbar DDD. Patients with a painful extrusion lumbar disc may gain some benefits after receiving IDB following a period of failed conservative treatment. These findings may also add some references for physicians in the decision making when treating lumbar DDD.
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Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Dor Lombar , Humanos , Seguimentos , Prognóstico , Radiografia , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/terapia , Degeneração do Disco Intervertebral/complicações , Dor Lombar/diagnóstico por imagem , Dor Lombar/etiologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Resultado do Tratamento , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/terapiaRESUMO
Herein, we designed a dual 3D DNA nanomachine (DDNM)-mediated catalytic hairpin assembly (DDNM-CHA) to construct an electrochemical biosensor for ultrasensitive detection of miRNA, which possesses quite a faster reaction rate and much higher amplification efficiency than those of traditional catalytic hairpin assembly (CHA). Impressively, since the DDNM skillfully increases the local concentration of reactants and decreases the steric hindrance of substrates simultaneously, the DDNM-CHA could be endowed with higher collision efficiency and more effective reaction compared with traditional CHA, resulting in a hyper conversion efficiency up to 2.78 × 107 only in 25 min. This way, the developed DDNM-CHA could easily conquer the main predicaments: long reaction time and low efficiency. As a proof of the concept, we adopt the gold nanoparticles (AuNPs) and the magnetic nanoparticle (Fe3O4) as the kernel of DNM-A and DNM-B, respectively, and harness the magnetic electrode to directly adsorb the products H1-H2/Fe3O4 for constructing an immobilization-free biosensor for high-speed and ultrasensitive detection of miRNA with a detection limit of 0.14 fM. As a result, the DDNM-CHA we developed carves out a new insight to design a functional DNA nanomachine and evolve the analysis method for practical amplification in the sensing area and promotes the deeper exploration of the nucleic acid signal amplification strategy and DNA nanobiotechnology.
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Técnicas Biossensoriais , DNA Catalítico , Nanopartículas Metálicas , MicroRNAs , DNA , Técnicas Eletroquímicas , Ouro , Limite de DetecçãoRESUMO
In this work, an original rolling-circle strand displacement amplification (RC-SDA) was developed by introducing a circle DNA with two recognition domains as a template instead of the limited liner DNA template in traditional strand displacement amplification (SDA), which displayed much shorter reaction time down to 30 min and quite higher conversion efficiency of more than 1.77 × 108 compared with those of traditional strand displacement amplification (SDA) and could be applied to construct a label-free biosensor for ultrasensitive detection of an HIV DNA fragment. Once the target HIV DNA fragment interacts with the template circle DNA, the RC-SDA could be activated to dramatically output amounts of mimic target DNA with the assistance of the Phi29 DNA polymerase and Nb.BbvCI enzyme. In application, while the output products were captured by the DNA tetrahedral nanoprobe (DTNP) modified electrode, the electrochemical tag silver nanoclusters (AgNCs) on DTNP would be released from the electrode surface, accompanied with an obviously decreased electrochemical signal. This way, the developed signal-off biosensor was successfully applied to realize the rapid and ultrasensitive detection of target HIV DNA fragment with a detection limit down to 0.21 fM, which exploits the new generation of a universal strategy beyond the traditional ones for applications in biosensing assay, clinic diagnosis, and DNA nanobiotechnology.
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Técnicas Biossensoriais , Técnicas Eletroquímicas , DNA/genética , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico , PrataRESUMO
BACKGROUND: The recent COVID-19 outbreak in Wuhan, China, has quickly spread throughout the world. In this study, we systematically reviewed the clinical features and outcomes of pregnant women with COVID-19. METHODS: PubMed, Web of Science, EMBASE and MEDLINE were searched from January 1, 2020, to April 16, 2020. Case reports and case series of pregnant women infected with SARS-CoV-2 were included. Two reviewers screened 366 studies and 14 studies were included. Four reviewers independently extracted the features from the studies. We used a random-effects model to analyse the incidence (P) and 95% confidence interval (95% CI). Heterogeneity was assessed using the I2 statistic. RESULTS: The meta-analysis included 236 pregnant women with COVID-19. The results were as follows: positive CT findings (71%; 95% CI, 0.49-0.93), caesarean section (65%; 95% CI, 0.42-0.87), fever (51%; 95% CI, 0.35-0.67), lymphopenia (49%; 95% CI, 0.29-0.70), coexisting disorders (33%; 95% CI, 0.21-0.44), cough (31%; 95% CI, 0.23-0.39), fetal distress (29%; 95% CI, 0.08-0.49), preterm labor (23%; 95% CI, 0.14-0.32), and severe case or death (12%; 95% CI, 0.03-0.20). The subgroup analysis showed that compared with non-pregnant patients, pregnant women with COVID-19 had significantly lower incidences of fever (pregnant women, 51%; non-pregnant patients, 91%; P < 0.00001) and cough (pregnant women, 31%; non-pregnant patients, 67%; P < 0.0001). CONCLUSIONS: The incidences of fever, cough and positive CT findings in pregnant women with COVID-19 are less than those in the normal population with COVID-19, but the rate of preterm labor is higher among pregnant with COVID-19 than among normal pregnant women. There is currently no evidence that COVID-19 can spread through vertical transmission.
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Betacoronavirus , Infecções por Coronavirus/epidemiologia , Trabalho de Parto Prematuro/epidemiologia , Pneumonia Viral/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , COVID-19 , Cesárea , China/epidemiologia , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/virologia , Tosse/epidemiologia , Tosse/virologia , Feminino , Febre/epidemiologia , Febre/virologia , Humanos , Incidência , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Trabalho de Parto Prematuro/virologia , Pandemias , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/virologia , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico por imagem , Complicações Infecciosas na Gravidez/virologia , Estudos Retrospectivos , SARS-CoV-2 , Tomografia Computadorizada por Raios XRESUMO
Rhizosphere CO2 is vital for crop growth, development, and productivity. However, the mechanisms of plants' responses to root-zone CO2 are unclear. Oriental melons are sensitive to root-zone gas, often encountering high root-zone CO2 during cultivation. We investigated root growth and nitrogen metabolism in oriental melons under T1 (0.5%) and T2 (1.0%) root-zone CO2 concentrations using physiology and comparative transcriptome analysis. T1 and T2 increased root vigor and the nitrogen content in the short term. With increased treatment time and CO2 concentration, root inhibition increased, characterized by decreased root absorption, incomplete root cell structure, accelerated starch accumulation and hydrolysis, and cell aging. We identified 1280 and 1042 differentially expressed genes from T1 and T2, respectively, compared with 0.037% CO2-grown plants. Among them, 683 co-expressed genes are involved in stress resistance and nitrogen metabolism (enhanced phenylpropanoid biosynthesis, hormone signal transduction, glutathione metabolism, and starch and sucrose metabolism). Nitrogen metabolism gene expression, enzyme activity, and nitrogen content analyses showed that short-term elevated root-zone CO2 mainly regulated plant nitrogen metabolism post-transcriptionally, and directly inhibited it transcriptionally in the long term. These findings provided a basis for further investigation of nitrogen regulation by candidate genes in oriental melons under elevated root-zone CO2.
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Dióxido de Carbono/metabolismo , Cucurbitaceae/fisiologia , Nitrogênio/metabolismo , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia , Plântula/fisiologia , Transcriptoma , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Redes e Vias Metabólicas , Fenótipo , Raízes de Plantas/ultraestrutura , Reprodutibilidade dos TestesRESUMO
Macroautophagy, a sole pathway for dysfunctional organelles or aggregated proteins turnover, has been implicated in the early development of Alzheimer's disease (AD). Previous studies have found that reversal of autophagy dysfunction in APP transgenic mice ameliorates amyloid pathologies. Icariin (ICA), the main component from traditional Chinese herb Epimedium brevicornu Maxim., can reduce accumulations of amyloid-ß (Aß) peptide in vivo and in vitro, but the mechanism remains unclear. Here, we explored the effects of ICA on autophagy-lysosomal pathway in intracerebroventricular (icv) injection of human Aß1-42 peptide rats. We demonstrated that feeding the rats with ICA (30 mg/kg, 60 mg/kg and 90 mg/kg rat, per os) for 4 weeks rescued the Aß1-42-induced spatial memory impairments, reduced endogenous rat Aß42 tested by ELISA and decreased Aß accumulation using 6E10 antibody. Furthermore, Aß1-42 induced strong autophagy response, however ICA decreased the levels of microtubule-associated protein 1 light chain 3 (LC3) II/LC3I, Beclin1, Cathepsin D (Cat D) and brain lysosomal Cathepsin D activity. We also observed that ICA enhanced the phosphorylation of protein kinase B (PKB/AKT) and p70 ribosomal protein S6 kinase (p70S6K). In addition, ICA arrested Aß1-42-induced cells loss, mitochondrias damage, nuclear membranes unclear and abundant nucleas chromatin agglutinates in hippocampus, lessened the expression of Cleaved-caspase-3, brain oxidative stress, astroglial activation. These findings suggest that ICA can ameliorate amyloid pathologies with improving autophagy-lysosome function and Chinese materia medica may be potential for AD treatment.
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Doença de Alzheimer/tratamento farmacológico , Flavonoides/uso terapêutico , Homeostase/efeitos dos fármacos , Macroautofagia/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Doença de Alzheimer/induzido quimicamente , Peptídeos beta-Amiloides/administração & dosagem , Animais , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Injeções , Lisossomos/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Fragmentos de Peptídeos/administração & dosagem , Ratos Sprague-Dawley , Memória Espacial/efeitos dos fármacosRESUMO
BACKGROUND The aim of this study was to evaluate the effects of carotid artery angioplasty and carotid artery stenting (CAS) on cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) in patients with preoperative cerebrovascular hemodynamic impairment. MATERIAL AND METHODS Seventeen patients with unilateral severe internal carotid artery (ICA) stenosis and ipsilateral CVR impairment underwent CAS. CBF and CVR were measured by single photon emission computed tomography (SPECT) with inhalation of carbon dioxide (CO2) one week before and three months after CAS. Sixty-eight ROIs in the middle cerebral artery (MCA) territory were analyzed in 17 patients. RESULTS Before CAS, CVR was impaired in all ROIs. CBF was impaired in 16 ROIs (23.5%). The percentage of ROIs with impaired CBF was significantly increased in patients with ≥90% carotid artery stenosis (p=0.047) without collateral flow through the circle of Willis (p=0.005). CAS significantly increased CVR in ROIs with a normal preoperative CBF and impaired CVR, indicating mild hemodynamic impairment (0.9±6.7% vs. 4.9±8.6%) (p=0.014). CAS significantly increased CBF in ROIs with preoperative impaired CBF and impaired CVR, indicating severe hemodynamic impairment (79.1±7.5% vs. 86.7±10.0%) (p<0.001). Following CAS, ROIs with normal CBF and impaired CVR had a significantly increased percentage of improved CVR (p=0.047); ROIs with impaired CBF and impaired CVR had a significantly increased percentage of improved CBF (p=0.027). CONCLUSIONS The severity of preoperative hemodynamic impairment, which is related to the degree of carotid artery stenosis and cerebral collateral flow, may influence hemodynamic benefits by CAS.
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Dióxido de Carbono/farmacologia , Estenose das Carótidas/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Angioplastia/métodos , Encéfalo/irrigação sanguínea , Dióxido de Carbono/metabolismo , Artérias Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Circulação Cerebrovascular/fisiologia , China , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , StentsRESUMO
Available microwave notch-type damage detection sensors are typically based on monitoring frequency shift or magnitude changes. However, frequency shift testing needs sweep-frequency data that make scanning detection becomes difficult and time-consuming. This work presents a microwave near-field nondestructive testing sensor for detecting sub-millimeter notch-type damage detection in metallic surfaces. The sensor is loaded with an interdigital electrode element in an open-ended coaxial. It is simple to fabricate and inexpensive, as it is etched on the RC4003 patch by using printed circuit board technology. The detection is achieved by monitoring changes in reflection amplitude, which is caused by perturbing the electromagnetic field around the interdigital structure. The proposed sensor was tested on a metallic plate with different defects, and the experimental results indicated that the interdigital electrode probe can determine the orientation, localization and dimension of surface notch-type damage.
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Most of the existing calibration methods for binocular stereo vision sensor (BSVS) depend on a high-accuracy target with feature points that are difficult and costly to manufacture and. In complex light conditions, optical filters are used for BSVS, but they affect imaging quality. Hence, the use of a high-accuracy target with certain-sized feature points for calibration is not feasible under such complex conditions. To solve these problems, a calibration method based on unknown-sized elliptical stripe images is proposed. With known intrinsic parameters, the proposed method adopts the elliptical stripes located on the parallel planes as a medium to calibrate BSVS online. In comparison with the common calibration methods, the proposed method avoids utilizing high-accuracy target with certain-sized feature points. Therefore, the proposed method is not only easy to implement but is a realistic method for the calibration of BSVS with optical filter. Changing the size of elliptical curves projected on the target solves the difficulty of applying the proposed method in different fields of view and distances. Simulative and physical experiments are conducted to validate the efficiency of the proposed method. When the field of view is approximately 400 mm × 300 mm, the proposed method can reach a calibration accuracy of 0.03 mm, which is comparable with that of Zhang's method.
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Nonindustrial low-cost cameras have the advantages of cheap and simple structure, but have the disadvantages of low resolution and large image noise. When the existing camera calibration methods are used to calibrate nonindustrial low-cost cameras, high-accuracy calibration cannot be obtained. A high-accuracy calibration method using a high-accuracy planar target is introduced in this study to solve this problem. First, the initial values and the uncertainties of all image feature points are determined by the multiscale image analysis method. Then, the image disturbance factor is added to each target image feature point. In addition, the image projection error is established as the minimum objective function according to the homography matrix between the target plane and the image plane. Thus, the optimal coordinates of all image feature points are obtained by the nonlinear optimization method. Finally, the calibration of the intrinsic and extrinsic parameters of the camera will be achieved by using Zhang's method according to the image feature points obtained from the previous step. Simulative and real experiments have been conducted to evaluate the performance of the proposed method, and results show that the calibration accuracy of the proposed method is at least three times that of Zhang's method.
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BACKGROUND: Endothelial progenitor cells (EPCs) play important roles in the regeneration of the vascular endothelial cells (ECs). Platelet-derived growth factor receptor (PDGFR)-ß is known to contribute to proliferation, migration, and angiogenesis of EPCs, this study aims to investigate effects of transplantation of EPCs overexpressing PDGFR-ß on vascular regeneration. METHODS: We transplanted genetically modified EPCs overexpressing PDGFR-ß into a mouse model with carotid artery injury. After 3 days of EPCs transplantation, the enhanced green fluorescent protein (EGFP)-expressing cells were found at the injury site and the lining of the lumen by laser scanning confocal microscope (LSCM). At 4, 7, and 14 days of the carotid artery injury, reendothelialization was evaluated by Evans Blue staining. Neointima formation was evaluated at day 14 with hematoxylin and eosin (HE) staining by calculating the neointimal area, medial area, and neointimal/media (NI/M) ratio. Intimal cell apoptosis was evaluated using TUNEL assay. Then we tested whether PDGF-BB-induced VSMC migration and PDGF-BB's function in reducing VSMC apoptosis can be attenuated by EPCs overexpressing PDGFR-ß in a transwell co-culture system. RESULTS: Our results showed that EPCs overexpressing PDGFR-ß accelerates reendothelialization and mitigates neointimal formation at 14 days after injury. Moreover, we found that there is great possibility that EPCs overexpressing PDGFR-ß enhanc VSMC apoptosis and suppress VSMC migration by competitive consumption of PDGF-BB in the early phase after carotid artery injury in mice. CONCLUSIONS: We report the first in vivo and in vitro evidence that transplantation of genetically modified EPC can have a combined effect of both amplifying the reendothelialization capacity of EPCs and inhibiting neointima formation so as to facilitate better inhibition of adverse remodeling after vascular injury.
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Lesões das Artérias Carótidas/cirurgia , Células Progenitoras Endoteliais/transplante , Endotélio Vascular/patologia , Regulação da Expressão Gênica , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Regeneração/genética , Transplante de Células-Tronco/métodos , Animais , Lesões das Artérias Carótidas/metabolismo , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neointima/patologia , RNA/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The on-site calibration of stereo vision sensors plays an important role in the measurement field. Image coordinate extraction of feature points of existing targets is difficult under complex light conditions in outdoor environments, such as strong light and backlight. This paper proposes an on-site calibration method for stereo vision sensors based on a spot laser projector for solving the above-mentioned problem. The proposed method is used to mediate the laser spots on the parallel planes for the purpose of calibrating the coordinate transformation matrix between two cameras. The optimal solution of a coordinate transformation matrix is then solved by nonlinear optimization. Simulation experiments and physical experiments are conducted to validate the performance of the proposed method. Under the condition that the field of view is approximately 400 mm×300 mm, the proposed method can reach a calibration accuracy of 0.02 mm. This accuracy value is comparable to that of the method using a planar target.
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A novel calibration method for the line-structured light vision sensor that only requires the image of the light stripe on the target using a movable parallel cylinder target is proposed in this paper. The corresponding equations between two ellipses obtained from the intersection of the light stripe and the target and their projected images are established according to the perspective projection transformation, and the light plane equation is solved based on the constraint conditions that the minor axis of the ellipse is equal to the diameter of the cylinder. In the physical experiment, the field of view of the line-structured light vision sensor is about 500 mm × 400 mm, and the measurement distance is about 700 mm. A calibration accuracy of 0.07 mm is achieved using the proposed method, which is comparable to that when planar targets are used.
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Relaxation of the inter- and intra-molecular interactions for the hydrogen bond (O:H-O) between undercoordinated molecules determines the unusual behavior of water nanodroplets and nanobubbles. However, probing such potentials remains unreality. Here we show that the Lagrangian solution [Huang et al., J. Phys. Chem. B, 2013. 117: 13639] transforms the observed H-O bond (x = H) and O:H nonbond (x = L) lengths and phonon frequencies (dx, ï·x) [Sun et al., J. Phys. Chem. Lett., 2013. 4: 2565] into the respective force constants and bond energies (kx, Ex) and hence enables the mapping of the potential paths for the O:H-O bond relaxing with water cluster size. Results show that molecular undercoordination not only reduces the molecular size (dH) with enhanced H-O energy from the bulk value of 3.97 to 5.10 eV for a H2O monomer, but also enlarges the molecular separation (dL) with reduced O:H energy from 95 to 35 meV for a dimer. The H-O energy gain raises the melting point from bulk value 273 to 310 K for the skin and the O:H energy loss lowers the freezing temperature from bulk value 258 to 202 K for 1.4 nm sized droplet, by dispersing the quasisolid phase boundaries.
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We developed a simple coordinate transformation method for quickly locating features of interest (FOIs) of samples in transmission electron microscope (TEM). The method is well suited for conducting sample searches in aberration-corrected scanning/transmission electron microscopes (S/TEM), where the survey can be very time-consuming because of the limited field of view imposed by the highly excited objective lens after fine-tuning the aberration correctors. For implementation, a digital image of the sample and the TEM holder was captured using a simple stereo-optical microscope. Naturally presented geometric patterns on the holder were referenced to construct a projective transformation between the electron and optical coordinate systems. The test results demonstrated that the method was accurate and required no electron microscope or specimen holder modifications. Additionally, it eliminated the need to mount the sample onto specific patterned TEM grids or deposit markers, resulting in universal applications for most TEM samples, holders and electron microscopes for fast FOI identification. Furthermore, we implemented the method into a Gatan script for graphical-user-interface-based step-by-step instructions. Through online communication, the script enabled real-time navigation and tracking of the motion of samples in TEM on enlarged optical images with a panoramic view.
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Small molecules with enzyme-like properties have recently attracted considerable attention. Herein, we discovered that nitrite possesses intrinsic oxidase-mimicking activity upon visible light, catalyzing the oxidation of the typical chromogenic substrate in the absence of H2O2. Notably, nitrite exhibited a markedly high value of Kcat, approximately 4, 7, and 4000-fold greater than that of Acr+-Mes, Eosin Y, and Diacetyl, respectively. Comprehensive investigation elucidated that O2â¢â» and â¢OH are the primary reactive oxygen species (ROS) responsible for the oxidation of 3,3',5,5'-tetramethylbenzidine dihydrochloride hydrate (TMB). Leveraging the linear correlation between the absorbance of oxidized TMB (oxTMB) at 652 nm and nitrite concentration, a simple colorimetric approach for nitrite detection was successfully established in the range of 1-75 µM with a detection limit of 0.14 µM. Moreover, the proposed strategy could be applied to determine the nitrite concentration in saliva, exhibiting a great prospect for clinical diagnosis. This work contributes novel insights into the exploration of small-molecule enzyme mimics.
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Colorimetria , Luz , Nitritos , Saliva , Saliva/química , Saliva/enzimologia , Nitritos/análise , Nitritos/química , Colorimetria/métodos , Humanos , Oxirredutases/química , Oxirredutases/metabolismo , Benzidinas/química , Oxirredução , Limite de DetecçãoRESUMO
Hydrogen-bonded organic frameworks (HOFs) are versatile materials with potential applications in proton conduction. Traditional approaches involve incorporating humidity control to address grain boundary challenges for proton conduction. This study finds vitrification as an alternative strategy to eliminate grain boundary effect in HOFs by rapidly melt quenching the kinetically stable HOF-SXU-8 to glassy state HOF-g. Notably, a remarkable enhancement in proton conductivity without humidity was achieved after vitrification, from 1.31 × 10-7 S cm-1 to 5.62× 10-2 S cm-1 at 100 °C. Long term stability test showed negligible performance degradation, and even at 30 °C, the proton conductivity remained at high level of 1.2 × 10-2 S cm-1. Molecule dynamics (MD) simulations and X-ray total scattering experiments reveal the HOF-g system is consisted of three kinds of clusters, i.e., 1,5-Naphthalenedisulfonic acid (1,5-NSA) anion clusters, N,N-dimethylformamide (DMF) molecule clusters, and H+-H2O clusters. In which, the H+ plays an important role to bridge these clusters and the high conductivity is mainly related to the H+ on H3O+. These findings provide valuable insights for optimizing HOFs, enabling efficient proton conduction, and advancing energy conversion and storage devices.
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BACKGROUND: Changes to the wound dressing frequently cause pain. Some adverse side effects of pharmacologic pain management may cause problems or even impede wound healing. There is no systematic study of non-pharmacologic therapies for pain during wound dressing changes, despite the gradual promotion of non-pharmacologic pain reduction methods. OBJECTIVES: To give clinical wound pain management a new direction, locating and assessing non-pharmacological interventions regarding pain brought on by wound dressing changes are necessary. METHOD: The researchers conducted a comprehensive literature review on non-pharmacological interventions for pain during wound dressing changes across five databases: PubMed, Web of Science, Medline, Embase, and the Cochrane Library spanning the period from January 2010 to September 2022. The evaluation of literature and data extraction was carried out independently by two researchers, and in cases of disagreement, a third researcher participated in the deliberation. To assess the risk of bias in the literature, the researchers utilised the Cochrane Handbook for Reviews of Interventions, version 5.1.0. RESULTS: In total, 951 people were involved in 11 investigations covering seven non-pharmacological therapies. For pain triggered by dressing changes, virtual reality (VR) distraction, auditory and visual distractions, foot reflexology, religious and spiritual care, and guided imaging demonstrated partially positive effects, with hypnosis therapy and jaw relaxation perhaps having a weak effect. CONCLUSION: The key to managing wounds is pain management. According to our review, there is some indication that non-pharmacologic interventions can help patients feel less discomfort when having their wound dressings changed. However, the evidence supporting this view is weak. It needs to be corroborated by future research studies with multicentre and large samples. To promote and use various non-pharmacologic interventions in the future, it is also necessary to build standardised and homogenised paths for their implementation.
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Bandagens , Dor , Ferimentos e Lesões , Humanos , Bandagens/efeitos adversos , Dor/etiologiaRESUMO
OBJECTIVE: To compare the clinical effects of coronary artery bypass grafting (CABG) between the left anterior small thoracotomy (LAST) and lower-end sternal splitting (LESS) approaches for coronary artery disease. METHODS: In total, 110 patients who underwent LAST from October 2015 to December 2020 in Tianjin Chest Hospital were selected as the observation group. Patients who underwent the LESS approach during the same period were analyzed. The propensity score was calculated by a logistic regression model, and nearest-neighbor matching was used for 1:1 matching. RESULTS: The length of hospital stay and ventilator support time were significantly shorter in the LAST than LESS group. The target vessels in the obtuse marginal branch and posterior left ventricular artery branch grafts were significantly more numerous in the LAST than LESS group, but those in the right coronary artery graft were significantly less numerous in the LAST group. CONCLUSIONS: CABG using either the LAST or LESS approach is safe and effective, especially in low-risk patients. The LAST approach can achieve complete revascularization for multivessel lesions and has the advantages of less trauma and an aesthetic outcome. However, it requires a certain learning curve to master the surgical techniques and has specific surgical indications.