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1.
Chemistry ; 30(2): e202302843, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37768323

RESUMO

Ammonia is vital for fertilizer production, hydrogen storage, and alternative fuels. The conventional Haber-Bosch process for ammonia production is energy-intensive and environmentally harmful. Designing environmentally friendly and low-energy consumption strategies for electrocatalytic N2 reduction reaction (ENRR) in mild conditions is meaningful. Single-atom catalysts (SACs) have been studied extensively for NRR due to their high atomic utilization and unique electronic structure but are limited by their poor faradic efficiency and low ammonia formation yield. Dual single-atom catalysts (DSACs) have recently emerged as a promising solution for the effective activation of molecular N2 , providing diverse active sites and synergistic interactions between adjacent atoms. In this review, we summarize the latest advances in metal DSACs for electrochemical ENRR based on both theoretical calculations and experimental studies, including aspects such as their variety, coordination, support, N2 adsorption and activity mechanisms, the characterization of NRR and electrochemical cell Configuration. We also address challenges and prospects in this rapidly evolving field, providing a comprehensive overview of DSACs for ENRR.

2.
Inorg Chem ; 63(10): 4707-4715, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38410082

RESUMO

A robust, microporous, and photoactive aluminum-based metal-organic framework (Al-MOF, LCU-600) has been assembled by an in situ-formed [Al3O(CO2)6] trinuclear building unit and a tritopic carbazole ligand. LCU-600 shows a high water stability and permanent porosity for N2 and CO2 adsorption. Notably, the incorporation of photoresponsive carbazole moieties into LCU-600 makes it a highly efficient and recyclable photocatalyst for aerobic photo-oxidation of sulfides into sulfoxides under an air atmosphere at room temperature. Mechanism investigations unveil that photogenerated holes (h+), superoxide radical anion (O2•-), and singlet oxygen (1O2) are critical active spices for the photo-oxidation reaction performed in an air atmosphere.

3.
Rev Esp Enferm Dig ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38235674

RESUMO

A 55-year-old male swallowed fish bone accidentally and subsequently developed retrosternal pain. He underwent chest computed tomography at his local hospital on October 23, 2023, showing esophageal foreign body with suspected esophageal rupture. One day later, he underwent endoscopy at our department, showing a fish bone penetrated into the esophageal wall. After consultation with cardiothoracic surgeons, endoscopy-guided removal of this foreign body was performed under anesthesia. An esophageal ulcer with a length of 2cm was left with overflowing air bubbles, and was closed by three metal clips. Two days later, retrosternal pain disappeared. A tube was intubated to duodenal distal segment under endoscopy, via which enteral nutritional suspension was given. Then, he was discharged.

4.
Small ; : e2304560, 2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37544918

RESUMO

Atomic-scale electrocatalysts greatly improve the performance and efficiency of water splitting but require special adjustments of the supporting structures for anchoring and dispersing metal single atoms. Here, the structural evolution of atomic-scale electrocatalysts for water splitting is reviewed based on different synthetic methods and structural properties that create different environments for electrocatalytic activity. The rate-determining step or intermediate state for hydrogen or oxygen evolution reactions is energetically stabilized by the coordination environment to the single-atom active site from the supporting material. In large-scale practical use, maximizing the loading amount of metal single atoms increases the efficiency of the electrocatalyst and reduces the economic cost. Dual-atom electrocatalysts with two different single-atom active sites react with an increased number of water molecules and reduce the adsorption energy of water derived from the difference in electronegativity between the two metal atoms. In particular, single-atom dimers induce asymmetric active sites that promote the degradation of H2 O to H2 or O2 evolution. Consequently, the structural properties of atomic-scale electrocatalysts clarify the atomic interrelation between the catalytic active sites and the supporting material to achieve maximum efficiency.

5.
Opt Express ; 31(20): 32813-32823, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859075

RESUMO

Optical frequency combs with more than 10 W have paved the way for extreme ultraviolet combs generation by interaction with inert gases, leading to extreme nonlinear spectroscopy and the ultraviolet nuclear clock. Recently, the demand for an ultra-long-distance time and frequency space transfer via optical dual-comb proposes a new challenge for high power frequency comb in respect of power scaling and optical frequency stability. Here we present a frequency comb based on fiber chirped pulse amplification (CPA), which can offer more than 20 W output power. We further characterize the amplifier branch noise contribution by comparing two methods of locking to an optical reference and measure the out-of-loop frequency instability by heterodyning two identical high-power combs. Thanks to the low noise CPA, reasonable locking method, and optical path-controlled amplifiers, the out-of-loop beat note between two combs demonstrates the unprecedented frequency stability of 4.35 × 10-17 at 1s and 6.54 × 10-19 at 1000 s.

6.
BMC Gastroenterol ; 23(1): 219, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365510

RESUMO

BACKGROUND: The optimal timing of endoscopy in liver cirrhosis with acute variceal bleeding (AVB) remains controversial in current guidelines and studies. METHODS: Consecutive patients with liver cirrhosis and AVB were screened. The timing of endoscopy was calculated from the last presentation of AVB or the admission to endoscopy. Early endoscopy was defined as the interval < 12 h, < 24 h, or < 48 h. A 1:1 propensity score matching (PSM) analysis was performed. Five-day failure to control bleeding and in-hospital mortality were evaluated. RESULTS: Overall, 534 patients were included. When the timing of endoscopy was calculated from the last presentation of AVB, PSM analysis demonstrated that the rate of 5-day failure to control bleeding was significantly higher in early endoscopy group defined as < 48 h (9.7% versus 2.4%, P = 0.009), but not < 12 h (8.7% versus 6.5%, P = 1.000) or < 24 h (13.4% versus 6.2%, P = 0.091), and that the in-hospital mortality was not significantly different between early and delayed endoscopy groups (< 12 h: 6.5% versus 4.3%, P = 1.000; <24 h: 4.1% versus 3.1%, P = 1.000; <48 h: 3.0% versus 2.4%, P = 1.000). When the timing of endoscopy was calculated from the admission, PSM analyses did not demonstrate any significant difference in the rate of 5-day failure to control bleeding (< 12 h: 4.8% versus 12.7%, P = 0.205; <24 h: 5.2% versus 7.7%, P = 0.355; <48 h: 4.5% versus 6.0%, P = 0.501) or in-hospital mortality (< 12 h: 4.8% versus 4.8%, P = 1.000; <24 h: 3.9% versus 2.6%, P = 0.750; <48 h: 2.0% versus 2.5%, P = 1.000) between early and delayed endoscopy groups. CONCLUSION: Our study could not support any significant association of timing of endoscopy with cirrhotic patients with AVB.


Assuntos
Varizes Esofágicas e Gástricas , Hemorragia Gastrointestinal , Humanos , Estudos Retrospectivos , Varizes Esofágicas e Gástricas/complicações , Cirrose Hepática/complicações , Endoscopia Gastrointestinal
7.
Tohoku J Exp Med ; 261(3): 187-194, 2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-37635063

RESUMO

Convection-enhanced delivery (CED) delivers agents directly into tumors and the surrounding parenchyma. Although a promising concept, clinical applications are often hampered by insufficient treatment efficacy. Toward developing an effective CED-based strategy for delivering drugs with proven clinical efficacy, we performed a basic characterization study to explore the locally delivered characteristics of the water soluble nitrosourea nimustine hydrochloride (ACNU). First, ACNU distribution after CED in rodent brain was studied using mass spectrometry imaging. Clearance of 14C-labeled ACNU after CED in striatum was also studied. ACNU was robustly distributed in rodent brain similar to the distribution of the hydrophilic dye Evans blue after CED, and locally delivered ACNU was observed for over 24 h at the delivery site. Subsequently, to investigate the potential of ACNU to induce an immunostimulative microenvironment, Fas and transforming growth factor-ß1 (TGF-ß1) was assessed in vitro. We found that ACNU significantly inhibited TGF-ß1 secretion and reduced Fas expression. Further, after CED of ACNU in 9L-derived intracranial tumors, the infiltration of CD4/CD8 lymphocytes in tumors was evaluated by immunofluorescence.CED of ACNU in xenografted intracranial tumors induced tumor infiltration of CD4/CD8 lymphocytes. ACNU has a robust distribution in rodent brain by CED, and delayed clearance of the drug was observed at the local infusion site. Further, local delivery of ACNU affects the tumor microenvironment and induces immune cell migration in tumor. These characteristics make ACNU a promising agent for CED.


Assuntos
Antineoplásicos , Neoplasias Encefálicas , Ratos , Animais , Nimustina/uso terapêutico , Fator de Crescimento Transformador beta1 , Ratos Endogâmicos F344 , Sistemas de Liberação de Medicamentos/métodos , Neoplasias Encefálicas/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Microambiente Tumoral
8.
Mikrochim Acta ; 190(3): 82, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36746802

RESUMO

Novel and portable cotton swab-based fluorometry was constructed for the first time for 3-aminosalicylic acid (3-ASA) and 5-aminosalicylic acid (5-ASA) detection. It was carried out by fluorescence enhancement on silver (Ag)-doped black phosphorus quantum dots (Ag@BPQD). Ag@BPQD were prepared from AgNO3 and bulk black phosphorus in N, N-dimethylformamide (DMF) solution by solvothermal decomposition after mechanical exfoliation. Ag@BPQD show blue fluorescence with a quantum yield (QY) of 2.43%. In the presence of Ag@BPQD, 3-ASA exhibited bright blue fluorescence (λex = 328 nm, λem = 448 nm). The fluorescence of 5-ASA was also enhanced significantly and exhibited bright green emission (λex = 328 nm, λem = 484 nm). The linear range of 3-ASA is 0-90 µM with a detection limit (LOD) of 0.10 µM, relative standard deviation (RSD) ≤ 2.04%, and a recovery range of 98.0-104.3%. The linear range of 5-ASA is 0-120 µM with a LOD of 0.12 µM, RSD ≤ 1.34%, and a recovery range of 98.0-101.3%. When 3-ASA and 5-ASA were mixed in different ratios, the fluorescence showed different colors. The possible mechanism of the interaction between 3-ASA (or 5-ASA) and Ag@BPQD may be ascribed to the generation of excited-state intramolecular proton transfer. To realize convenient detection of 3-ASA and 5-ASA, a Ag@BPQD portable sensing method using cotton swabs were built. The proposed approach provides the detection of 3-ASA and 5-ASA in environmental and biological samples with high efficiency, accuracy and portability.

9.
Rev Esp Enferm Dig ; 115(10): 546-552, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37114392

RESUMO

BACKGROUND AND AIMS: difficulty of cecal intubation should be a main indicator for the need of sedated colonoscopy and skilled endoscopists. The present study aimed to explore the factors associated with easy and difficult cecal intubation in unsedated colonoscopy. METHODS: all consecutive patients who underwent unsedated colonoscopy at our department by the same endoscopist from December 3, 2020 to August 30, 2022 were retrospectively collected. Age, gender, body mass index (BMI), reasons for colonoscopy, position change, Boston Bowel Preparation Scale score, cecal intubation time (CIT) and major colonoscopic findings were analyzed. CIT < 5 min, CIT 5-10 min and CIT > 10 min or failed cecal intubation were defined as easy, moderate and difficult cecal intubation, respectively. Logistic regression analyses were performed to identify independent factors associated with easy and difficult cecal intubation. RESULTS: overall, 1,281 patients were included. The proportions of easy and difficult cecal intubation were 29.2 % (374/1,281) and 27.2 % (349/1,281), respectively. Multivariate logistic regression analysis found that age ≤ 50 years, male, BMI > 23.0 kg/m2 and the absence of position change were independently associated with easy cecal intubation, and that age > 50 years, female, BMI ≤ 23.0 kg/m2, position change, and insufficient bowel preparation were independently associated with difficult cecal intubation. CONCLUSIONS: some convenient factors independently associated with easy and difficult cecal intubation have been identified, which will be potentially helpful to determine whether a colonoscopy should be sedated and a skilled endoscopist should be selected. The current findings should be further validated in large-scale prospective studies.


Assuntos
Ceco , Colonoscopia , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos Prospectivos , Índice de Massa Corporal
10.
J Clin Gastroenterol ; 56(3): e250-e262, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33780217

RESUMO

BACKGROUND: Cervical inlet patch (CIP), also called gastric inlet patch, is a heterotopic columnar mucosal island located in the cervical esophagus, which has been under-recognized by clinicians. AIM: We conducted a systemic review and meta-analysis to explore the prevalence and clinical and endoscopic characteristics of CIP. MATERIALS AND METHODS: Studies were searched through the PubMed, EMBASE, and Cochrane Library databases. The prevalence of CIP with 95% confidence interval (CI) was pooled by using a random-effect model. The association of CIP with demographics, clinical presentations, and endoscopic features was evaluated by odds ratios (ORs). RESULTS: Fifty-three studies including 932,777 patients were eligible. The pooled prevalence of CIP was 3.32% (95% CI=2.86%-3.82%). According to the endoscopic mode, the pooled prevalence of CIP was higher in studies using narrow-band imaging than in those using white light and esophageal capsule endoscopy (9.34% vs. 2.88% and 0.65%). The pooled prevalence of CIP was higher in studies where the endoscopists paid specific attention to the detection of this lesion (5.30% vs. 0.75%). CIP was significantly associated with male (OR=1.24, 95% CI=1.09-1.42, P=0.001), gastroesophageal reflux disease (OR=1.32, 95% CI=1.04-1.68, P=0.03), reflux symptoms (OR=1.44, 95% CI=1.14-1.83, P=0.002), dysphagia (OR=1.88, 95% CI=1.28-2.77, P=0.001), throat discomfort (OR=4.58, 95% CI=1.00-21.02, P=0.05), globus (OR=2.95, 95% CI=1.52-5.73, P=0.001), hoarseness (OR=4.32, 95% CI=1.91-9.78, P=0.0004), cough (OR=3.48, 95% CI=1.13-10.72, P=0.03), Barrett's esophagus (OR=2.01, 95% CI=1.37-2.94, P=0.0003), and esophagitis (OR=1.62, 95% CI=1.27-2.07, P=0.0001). CONCLUSION: CIP appears to be common by using narrow-band imaging, especially if the endoscopists would like to pay attention to the detection of this lesion. CIP is clearly associated with acid-related symptoms and Barrett's esophagus.


Assuntos
Esôfago de Barrett , Coristoma , Doenças do Esôfago , Esôfago de Barrett/patologia , Baías , Coristoma/epidemiologia , Doenças do Esôfago/diagnóstico , Esofagoscopia , Mucosa Gástrica/patologia , Humanos , Masculino , Prevalência
11.
J Fluoresc ; 32(2): 759-770, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35089458

RESUMO

It was the first time to report the aggregation induced emission (AIE) of acetaldehyde (AA) on the surface of carbonized polymer dots (CPDs) with the auxiliary of Tb3+. Based on the AIE of AA, a turn-off-on fluorescence method was established for AA detection using the porous CPDs-Tb3+ system. The one-pot hydrothermal method was used to obtain CPDs, using milk and polyethyleneimine (PEI) as precursors. In the presence of Tb3+, CPDs aggregated immediately and even forming precipitate, and the fluorescence intensity decreased obviously. AA can effectively embed on the surface of CPDs-Tb3+ due to the porous structure. AA displayed obviously blue fluorescence with excitation wavelength at 370 nm (emission peak at 460 nm), while there was no fluorescence peak when excited at 460 nm. In the CPDs-Tb3+ solution, AA exhibits obvious fluorescence enhancement effect (λex 460 nm, λem 545 nm). And then, AA can be determined by the turn-off-on system based on the linear relationship between fluorescence enhancement and the concentration of AA ranging from 0.04 mM to 42.48 mM. The limit of detection (LOD) was 0.02 mM. The turn-off-on system was successfully applied to determine AA in wine samples. The strategy may be exploited to monitor AA in more drinking or foodstuff samples.

12.
J Fluoresc ; 32(6): 2343-2350, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36156168

RESUMO

Carbon dots (CDs) were used to develop a sensitive sensing technique for detecting Cr(VI). CDs were made using a hydrothermal technique from citric acid and glutamic acid. These prepared CDs emitted blue fluorescence under excitation of 350 nm (λem = 420 nm), and the fluorescence quantum yield was 48.41%. Transmission electron microscope was used to examine the morphology of the CDs, which had an average size of 2.21 ± 0.39 nm. The elementary composition and bonding structure of the CDs were conducted by XPS and FT-IR spectrum. Cr(VI) quenched the fluorescence of CDs through a static quenching effect and an inner filter effect, allowing Cr(VI) to be detected quantitatively. This approach was used to detect Cr(VI) in two samples of water, with the findings demonstrating that it is reliable and accurate. The fluorescence intensity change was linearly related to the concentration of Cr(VI) in the range from 0.5 to 400 µM, with the detection limit being 0.10 µM. This approach has the virtues of wide detection range, low cost and fast response. The strategy has a great application prospect for detecting Cr(VI) in practical samples.


Assuntos
Carbono , Pontos Quânticos , Carbono/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Ácido Glutâmico , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Ácido Cítrico
13.
Graefes Arch Clin Exp Ophthalmol ; 260(1): 335-343, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34436647

RESUMO

PURPOSE: To assess the longitudinal change in components of astigmatism from age 4 to 7 years and its association with axial length-corneal radius ratio (AL/CR). METHODS: Children born between September 2011 and August 2012 in Yuhuatai District of Nanjing were invited to participate in the Nanjing Eye Study for a comprehensive eye examination annually since 2015. The data presented in this paper were obtained in 2016, 2017, and 2019. At each study encounter, noncycloplegic autorefraction and ocular biometric parameters were measured. Changes of total astigmatism (TA), corneal astigmatism (CA), anterior corneal astigmatism (ACA), residual astigmatism (RA), and internal astigmatism (IA) were analyzed in clinical notation (Cyl) and vector notation (J0, J45). RESULTS: Nine hundred fifty-four children (mean ± standard deviation of baseline age: 4.63 ± 0.29 years, 53.7% boys) had complete data and were included in this study. Mean slopes of longitudinal changes in Cyl notation were significantly negative for TA, CA, and ACA, but positive for IA. TA, CA, ACA, and RA of J0 notation had a shift toward increasing with-the-rule (WTR) astigmatism and/or decreasing against-the-rule (ATR) astigmatism. TA of J45 notation showed an increase in astigmatism at axis 135° and/or a decrease in astigmatism at axis 45°, while CA and ACA of J45 notation showed an opposite change. Longitudinal changes in ACA and IA were negatively correlated in J0 notation, but not in J45 notation. Based on compensation factor (CF, defined as the minus ratio of IA and ACA), the compensation proportions for J0 in varying degrees (CF: 0.1-2) in 2016, 2017, and 2019 were 91.3%, 93.5%, and 90.0%, respectively, while these for J45 were 74.9%, 76.5%, and 34.6%, respectively. Higher AL/CR increase was associated with less decrease or more increase in CA and ACA of Cyl notation, and a shift toward increasing WTR and/or decreasing ATR in these of J0 notation. CONCLUSIONS: The compensatory role of IA was persistent and prominent from 4 to 7 years old for J0 notation in Chinese young children. The progression of AL/CR was correlated with astigmatism originated from the cornea.


Assuntos
Astigmatismo , Astigmatismo/diagnóstico , Biometria , Criança , Pré-Escolar , China/epidemiologia , Córnea , Feminino , Humanos , Masculino , Rádio (Anatomia) , Refração Ocular
14.
J Fluoresc ; 30(6): 1447-1456, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32780262

RESUMO

Carbon dots (CDs) with different doping elements were successfully synthesized via a simple hydrothermal strategy. 3-amino-4-chlorophenylboronic acid, 3-aminobenzeneboronic acid, aniline, and benzene were used as precursors, respectively. The B/N co-doping CDs (BNCDs) derived from 3-aminobenzeneboronic acid show brightest fluorescence among the CDs products with quantum yield at 0.15. The fluorescence of BNCDs exhibits good photostability and excitation-independent emission behavior. The bright blue emission of BNCDs can be quenched by serine, which is a kind of neutral aliphatic amino acid containing hyroxyl groups with polarity. It is possibly due to the molecular collision between excited state of BNCDs and the ground state of serine. BNCDs can be served as fluorophore probe for the assay of serine based on the efficient quenching effect. The approach for the determination of serine shows a high sensitivity with a detection limit at 0.14 nM, which is lower than those of previous works. Furthermore, the present BNCDs system can be employed to monitor serine in real food and biological samples. The strategy may be a potential way for the application in food safety and biomedicine fields.

15.
Sensors (Basel) ; 20(16)2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32784950

RESUMO

The process parameters of selective laser melting (SLM) significantly influence molten pool formation. A comprehensive understanding and analysis, from a macroscopic viewpoint, of the mechanisms underlying these technological parameters and how they affect the evolution of molten pools are presently lacking. In this study, we established a dynamic finite element simulation method for the process of molten pool formation by SLM using a dynamic moving heat source. The molten pool was generated, and the dynamic growth process of the molten pool belt and the evolution process of the thermal field of the SLM molten pool were simulated. Then, a deposition experiment that implemented a new measurement method for online monitoring involving laser supplementary light was conducted using the same process parameters as the simulation, in which high-speed images of the molten pool were acquired, including images of the pool surface and cross-section images of the deposited samples. The obtained experimental results show a good agreement with the simulation results, demonstrating the effectiveness of the proposed algorithm.

16.
Opt Lett ; 44(22): 5489-5492, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730090

RESUMO

We demonstrate ultra-low-noise carrier-envelope phase stabilization of a Kerr-lens mode-locked Yb:CYA laser frequency comb, which is the first time, to the best of our knowledge, that the feed-forward method has been applied to 1 µm all-solid-state lasers. We obtain a signal-to-noise ratio of more than 38 dB at a 100 kHz resolution bandwidth for carrier-envelope phase offset beat signals in two standard in-loop and out-of-loop f-2f interferometers. The residual integrated phase noise amounts to 79.3 mrad from 1 Hz to 1 MHz, corresponding to a timing jitter of 44 as. We also investigate long-term performances of the CEP stabilization in the feed-forward scheme, phase-locked feedback systems and the combining locking techniques in terms of sub-hertz frequency-resolved phase noise and Allan deviation in 1000 s. The results indicate that, although the feed-forward CEP stabilization method dominates in the range of 1 Hz to 1 MHz Fourier frequency, feedback methods with a time integration effect are superior in sub-hertz Fourier frequency phase noise suppression.

17.
Entropy (Basel) ; 20(12)2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33266702

RESUMO

A new type of multi-baffle-type heat sink is proposed in this paper. The heat-transfer coefficient and pressure drop penalty of the employed six heat sink models are numerically investigated under five different inlet velocities. It is shown that Model 6 (M6) has excellent heat transfer performance as its heat-transfer coefficient reaches a value of 1758.59 W/m2K with a pressure drop of 2.96 × 104 Pa, and the temperature difference between the maximum and the minimum temperature of the heating surface is 51.7 K. The results showed that the coolant for M6 is distributed evenly to each channel at the maximal degree. The phenomena of the maldistribution of temperature is effectively improved. Moreover, the thermal resistance and thermal enhancement factor for the six models is also examined. M6 possesses the lowest total thermal resistance and largest thermal enhancement factor compared to the other five models. Furthermore, an experimental platform is set up to verify the simulation results obtained for M6. The simulated heat-transfer coefficient and pressure drop values agree well with the experimental results.

18.
Cell Physiol Biochem ; 43(2): 636-643, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28942448

RESUMO

BACKGROUND: MiR-134 is enriched in dendrites of hippocampal neurons and plays crucial roles in the progress of epilepsy. The present study aims to investigate the effects of antagomirs targeting miroRNA-134 (Ant-134) on limk1 expression and the binding of miR-134 and limk1 in experimental seizure. METHODS: Status epilepticus (SE) rat model was established by lithium chloride-pilocarpine injection and was treated with Ant-134 by intracerebroventricular injection. Low Mg2+-exposed primary neurons were used as an in vitro model of SE. The expression of miR-134 was determined using real-time PCR. Protein expressions of limk1 and cofilin were determined by Western blotting. Luciferase reporter assay was used to examine the binding between miR-134 and limk1 3'-untranslated region. RESULTS: The expression of miR-134 was markedly enhanced in hippocampus of the SE rats and low Mg2+-exposed neurons. Ant-134 increased the expression of limk1 and reduced the expression of cofilin in the SE hippocampus and Low Mg2+-exposed neurons. In addition, luciferase reporter assay confirmed that miR-134 bound limk1 3'-UTR. MiR-134 overexpression inhibited limk1 mRNA and protein expressions in neurons. CONCLUSION: Blockage of miR-134 upregulates limk1 expression and downregulated cofilin expression in hippocampus of the SE rats. This mechanism may contribute to the neuroprotective effects of Ant-134.


Assuntos
Antagomirs/uso terapêutico , Quinases Lim/genética , MicroRNAs/genética , Convulsões/terapia , Estado Epiléptico/terapia , Regulação para Cima , Animais , Células Cultivadas , Terapia Genética , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Neurônios/metabolismo , Neurônios/patologia , Ratos Sprague-Dawley , Convulsões/genética , Convulsões/patologia , Estado Epiléptico/genética , Estado Epiléptico/patologia
19.
Med Sci Monit ; 23: 2527-2534, 2017 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-28542116

RESUMO

BACKGROUND This is a retrospective observational study evaluating the prevalence and clinical characteristics of spontaneous splenorenal shunt in liver cirrhosis. MATERIAL AND METHODS We included a total of 105 cirrhotic patients who were admitted to our hospital between June 2012 and December 2013 and underwent contrast-enhanced CT and/or MRI scans at admissions. Spontaneous splenorenal shunt was identified. Clinical and laboratory data were compared between cirrhotic patients with and without spontaneous splenorenal shunt. RESULTS The prevalence of spontaneous splenorenal shunt was 10.5% (11/105). The prevalence of hepatic encephalopathy was higher in patients with spontaneous splenorenal shunt than in those without spontaneous splenorenal shunt (18.2% vs. 4.3%, p=0.062), but the difference between them was not statistically significant. The prevalence of acute upper-gastrointestinal bleeding was lower in patients with spontaneous splenorenal shunt than in those without spontaneous splenorenal shunt (0% vs. 18.1%, p=0.205), but the difference between them was not statistically significant. Patients with spontaneous splenorenal shunt had significantly higher Child-Pugh scores (9.50±1.65 vs. 7.43±2.02, p=0.002) and MELD scores (11.26±7.29 vs. 5.67±6.83, p=0.017) than those without spontaneous splenorenal shunt. In-hospital mortality was similar between them (0% vs. 4.3%, p=1.000). CONCLUSIONS Spontaneous splenorenal shunt might be associated with worse liver function in liver cirrhosis, but not with in-hospital mortality.


Assuntos
Meios de Contraste/química , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/epidemiologia , Imageamento por Ressonância Magnética , Derivação Esplenorrenal Cirúrgica/estatística & dados numéricos , Tomografia Computadorizada por Raios X , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos
20.
Med Sci Monit ; 22: 2720-30, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27480906

RESUMO

BACKGROUND The prognostic role of serum liver fibrosis markers in cirrhotic patients remains unclear. We performed a prospective observational study to evaluate the effect of amino-terminal pro-peptide of type III pro-collagen (PIIINP), collagen IV (CIV), laminin (LN), and hyaluronic acid (HA) on the prognosis of liver cirrhosis. MATERIAL AND METHODS All patients who were diagnosed with liver cirrhosis and admitted to our department were prospectively enrolled. PIIINP, CIV, LN, and HA levels were tested. RESULTS Overall, 108 cirrhotic patients were included. Correlation analysis demonstrated that CIV (coefficient r: 0.658, p<0.001; coefficient r: 0.368, p<0.001), LN (coefficient r: 0.450, p<0.001; coefficient r: 0.343, p<0.001), and HA (coefficient r: 0.325, p=0.001; coefficient r: 0.282, p=0.004) levels, but not PIIINP level (coefficient r: 0.081, p=0.414; coefficient r: 0.090, p=0.363), significantly correlated with Child-Pugh and MELD scores. Logistic regression analysis demonstrated that HA (odds ratio=1.00003, 95% confidence interval [CI]=1.000004-1.000056, p=0.022) was significantly associated with the 6-month mortality. Receiver operating characteristics analysis demonstrated that the area under the curve (AUC) of HA for predicting the 6-month mortality was 0.612 (95%CI=0.508-0.709, p=0.1531). CONCLUSIONS CIV, LN, and HA levels were significantly associated with the severity of liver dysfunction, but might be inappropriate for the prognostic assessment of liver cirrhosis.


Assuntos
Cirrose Hepática/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Colágeno Tipo IV/sangue , Feminino , Hepatite B Crônica/sangue , Hepatite B Crônica/patologia , Humanos , Ácido Hialurônico/sangue , Laminina/sangue , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Prognóstico , Estudos Prospectivos , Curva ROC
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