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1.
J Biomech Eng ; 146(8)2024 08 01.
Article in English | MEDLINE | ID: mdl-38491980

ABSTRACT

Radio frequency ablation has emerged as a widely accepted treatment for atherosclerotic plaques. However, monitoring the temperature field distribution in the blood vessel wall during this procedure presents challenges. This limitation increases the risk of endothelial cell damage and inflammatory responses, potentially leading to lumen restenosis. The aim of this study is to accurately reconstruct the transient temperature distribution by solving a stochastic heat transfer model with uncertain parameters using an inverse heat transfer algorithm and temperature measurement data. The nonlinear least squares optimization method, Levenberg-Marquardt (LM), was employed to solve the inverse heat transfer problem for parameter estimation. Then, to improve the convergence of the algorithm and reduce the computational resources, a method of parameter sensitivity analysis was proposed to select parameters mainly affecting the temperature field. Furthermore, the robustness and accuracy of the algorithm were verified by introducing random noise to the temperature measurements. Despite the high level of temperature measurement noise (ξ = 5%) and larger initial guess deviation, the parameter estimation results remained closely aligned with the actual values, with an overall ERMS consistently below 0.05. The absolute errors between the reconstruction temperature at the measurement points TC1, TC2, and TC3, and the actual temperature, remained within 0.33 °C, 2.4 °C, and 1.17 °C, respectively. The Levenberg-Marquardt algorithm employed in this study proficiently tackled the ill-posed issue of inversion process and obtained a strong consistency between the reconstructed temperature the actual temperature.


Subject(s)
Plaque, Atherosclerotic , Radiofrequency Ablation , Humans , Temperature , Hot Temperature , Body Temperature , Algorithms
2.
Langmuir ; 39(31): 11048-11062, 2023 08 08.
Article in English | MEDLINE | ID: mdl-37497679

ABSTRACT

Rapid and uniform rewarming is critical to cryopreservation. Current rapid rewarming methods require complex physical field application devices (such as lasers or radio frequencies) and the addition of nanoparticles as heating media. These complex devices and nanoparticles limit the promotion of the rapid rewarming method and pose potential biosafety concerns. In this work, a joule heating-based rapid electric heating chip (EHC) was designed for cryopreservation. Uniform and rapid rewarming of biological samples in different volumes can be achieved through simple operations. EHC loaded with 0.28 mL of CPA solution can achieve a rewarming rate of 3.2 × 105 °C/min (2.8 mL with 2.3 × 103 °C/min), approximately 2 orders of magnitude greater than the rewarming rates observed with an equal capacity straw when combined with laser nanowarming or magnetic induction heating. In addition, the degree of supercooling can be significantly reduced without manual nucleation during the cooling of the EHC. Subsequently, the results of cryopreservation validation of cells and spheroids showed that the cell viability and spheroid structural integrity were significantly improved after cryopreservation. The viability of human lung adenocarcinoma (A549) cells postcryopreservation was 97.2%, which was significantly higher than 93% in the cryogenic vials (CV) group. Similar results were seen in human mesenchymal stem cells (MSCs), with 93.18% cell survival in the EHC group, significantly higher than 86.83% in the CV group, and cells in the EHC group were also significantly better than those in the CV group for further apoptosis and necrosis assays. This work provides an efficient rewarming protocol for the cryopreservation of biological samples, significantly improving the quantity and quality of cells and spheroids postcryopreservation.


Subject(s)
Heating , Rewarming , Humans , Cryopreservation , Apoptosis , Cold Temperature , Cryoprotective Agents/chemistry
3.
J Clin Ultrasound ; 51(1): 74-81, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36082876

ABSTRACT

OBJECTIVES: This study aimed to evaluate the feasibility of monitoring fetal intracranial volume using three-dimensional ultrasound virtual organ computer-aided analysis (VOCAL) technology and to analyze normal fetal brain growth. METHODS: This multi-center prospective cross-sectional study included 821 pregnant women (18-40 gestational weeks) divided into 23 groups according to gestational week. We used transabdominal three-dimensional ultrasound VOCAL to monitor fetal intracranial volume; explore the correlation between intracranial volume and gestational age, biparietal diameter (BPD), and head circumference (HC); and analyze the proportion of brain weight to body weight. RESULTS: The intracranial volume of normal fetuses conformed to the normal distribution, gradually increased with gestational age, and was highly correlated with gestational age (r = 0.977), BPD (r = 0.975), and HC (r = 0.953; p < 0.001). The median percentage of brain weight (BW) to estimated fetal weight (EFW) was between 13% and 21%, and the BW/EFW ratio showed a significant downward trend in the third trimester. The VOCAL technology monitored the fetal intracranial volume with good repeatability. CONCLUSIONS: VOCAL technology is feasible for monitoring the fetal intracranial volume, and the intracranial volume increases more than 10-times in the second and third trimesters.


Subject(s)
East Asian People , Ultrasonography, Prenatal , Pregnancy , Female , Humans , Cross-Sectional Studies , Prospective Studies , Ultrasonography, Prenatal/methods , Fetal Development , Fetal Weight , Gestational Age , Computers
4.
Nanotechnology ; 31(39): 395702, 2020 Sep 25.
Article in English | MEDLINE | ID: mdl-32521516

ABSTRACT

A simple method was developed to prepare fluorescent nitrogen/boron-doped carbon dots (N,B-CDs) in the gram scale. The results showed that the CDs exhibited blue photoluminescence (PL) under 365 nm ultraviolet radiation and excitation-dependent emission. Heteroatoms entered the CDs to enhance the photochemical properties, and their positive properties can be attributed to the presence of guanidino group and functionalized with boronic acid for realizing their utilization in certain applications. These materials could be applied to monitor Fe3+ via static PL quenching, yielding a limit of detection (LOD) of 0.74 µM. Furthermore, the charged and boronic acid groups on the prepared N,B-CDs enabled their use as recognition elements to bind with the bacteria through electrostatic interaction and allowed covalent interactions to form the corresponding boronate ester with E. coli (E. coli) bacterial membrane. This method could satisfy a linear range of 102-107 with LOD of 165 cfu ml-1 for E. coli. This method was applied for the determination of E. coli in tap water and orange juice samples, and satisfactory results were obtained.


Subject(s)
Boron/chemistry , Carbon/chemistry , Escherichia coli/isolation & purification , Iron/analysis , Nitrogen/chemistry , Biosensing Techniques , Fluorescence , Limit of Detection , Quantum Dots/chemistry , Static Electricity
5.
Acta Pharmacol Sin ; 40(2): 160-169, 2019 Feb.
Article in English | MEDLINE | ID: mdl-29925921

ABSTRACT

There is an urgent need to develop effective therapies for ischemic stroke, but the complicated pathological processes after ischemia make doing so difficult. In the current study, we identified a novel diaryl acylhydrazone derivative, A11, which has multiple neuroprotective properties in ischemic stroke models. First, A11 was demonstrated to induce neuroprotection against ischemic injury in a dose-dependent manner (from 0.3 to 3 µM) in three in vitro experimental ischemic stroke models: oxygen glucose deprivation (OGD), hydrogen peroxide, and glutamate-stimulated neuronal cell injury models. Moreover, A11 was able to potently alleviate three critical pathological changes, apoptosis, oxidative stress, and mitochondrial dysfunction, following ischemic insult in neuronal cells. Further analysis revealed that A11 upregulated the phosphorylation levels of protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) in OGD-exposed neuronal cells, suggesting joint activation of the phosphoinositide 3-kinase (PI3K)/AKT and mitogen-activated protein kinase (MEK)/ERK pathways. In rats with middle cerebral artery occlusion, single-dose administration of A11 (3 mg/kg per day, i.v.) at the onset of reperfusion significantly reduced the infarct volumes and ameliorated neurological deficits. Our study, for the first time, reports the anti-ischemic effect of diaryl acylhydrazone chemical entities, especially A11, which acts on multiple ischemia-associated pathological processes. Our results may provide new clues for the development of an effective therapeutic agent for ischemic stroke.


Subject(s)
Hydrazones/therapeutic use , Infarction, Middle Cerebral Artery/drug therapy , Neuroprotective Agents/therapeutic use , Reperfusion Injury/drug therapy , Animals , Apoptosis/drug effects , Cell Line, Tumor , Humans , Hydrazones/pharmacology , Male , Mitochondrial Diseases/drug therapy , Neurons/drug effects , Neuroprotective Agents/pharmacology , Oxidative Stress/drug effects , Rats, Sprague-Dawley
6.
Pharmazie ; 74(7): 390-396, 2019 07 01.
Article in English | MEDLINE | ID: mdl-31288894

ABSTRACT

Previous studies showed that DEFB1 gene polymorphisms may impact the development and progression of periodontitis; nevertheless, inconsistent conclusions were described. This study meta-analytically explored the association between periodontitis the DEFB1 gene polymorphisms and periodontitis. We searched PubMed, Embase, Springer and Cochrane Library for the relevant case-control studies of periodontitis up to February 13th, 2019. Two reviewers selected studies according to the predefined inclusion and exclusion criteria. Newcastle-Ottawa Scale (NOS) was used to assess the quality of studies, and the combined effect size was calculated using R 3.12 software. A total of 9 studies involving 4113 patients and 2373 controls were included. Meta-analysis of DEFB1-G1654A gene polymorphisms showed that there were significant differences in model A vs. G (OR = 3.7876, 95%CI = 2.9051-4.9382, P < 0.001), AA vs. GG (OR = 4.6743, 95%CI = 3.0900-7.0710, P < 0.001), AA vs.GG + AG (OR = 3.5131, 95%CI = 2.4496-5.0384, P < 0.001), AA + AG vs. GG (OR = 4.3087, 95%CI = 2.8827-6.4402, P < 0.001) and AG vs. GG (OR = 3.0639, 95%CI = 1.6804-5.5863, P = 0.003). However, no significant differences were found between DEFB1 rs11362, rs1799946 and rs1800972 and periodontitis. Sensitivity analysis implied that our results were robust and no publication bias was noticed. Our meta-analysis showed that the DEFB1-G1654A polymorphism may be a genetic susceptibility factor for periodontitis.


Subject(s)
Genetic Predisposition to Disease , Periodontitis/genetics , beta-Defensins/genetics , Humans , Periodontitis/epidemiology , Periodontitis/pathology , Polymorphism, Single Nucleotide
7.
J Matern Fetal Neonatal Med ; 36(1): 2157257, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36521849

ABSTRACT

OBJECTIVES: Congenital hemangiomas are rare benign vascular tumors but can lead to serious adverse pregnancy outcomes. Its prenatal diagnosis is a challenge. We explored the clinical applications of prenatal ultrasound for evaluating fetal cutaneous hemangioma and associated complications. METHODS: A retrospective observational study was conducted comprising a population of pregnant women with fetal cutaneous hemangioma, the latter diagnosed by prenatal ultrasound, between January 2016 and December 2020. The clinical characteristics, sonographic images, complications, and pregnancy outcomes were documented and analyzed. RESULTS: We identified 20 cases of fetal cutaneous hemangioma diagnosed by prenatal ultrasound and confirmed by postpartum examinations. Most hemangiomas were in the head and neck (55%), with either solid isoechoicity (25%) or solid mildly hyperechoic (25%), and well-circumscribed (80%) mass. Eight (40%) fetuses experienced complications, which often occurred in fetuses with large hemangiomas (67% with maximum diameter ≥5 cm; 100% with a volume ≥40 cm3). The most common complications were cardiac-related (88%), including elevated cardiothoracic area ratio, atrioventricular valve regurgitation, and fetal hydrops. A large hemangioma was usually associated with advanced gestational age and a fast hemangioma growth rate. In five (25%) cases, the pregnancy was terminated; these involved hemangioma of the head or neck. One newborn developed Kasabach-Merritt phenomenon, pulmonary hemorrhage and respiratory distress, and died 3 days after birth. Among the 14 (70%) fetuses that survived birth, all hemangiomas disappeared or regressed after treatments with propranolol, interventional surgery, or observed routinely. CONCLUSIONS: Prenatal ultrasound examination can accurately diagnose fetal cutaneous hemangioma and related complications to facilitate appropriate management during the pregnancy. RATIONALE: Prenatal diagnosis of cutaneous hemangiomas is a clinical challenge. Prenatal ultrasound examination could be a method to accurately diagnose and monitor these hemangiomas.


Subject(s)
Hemangioma , Infant, Newborn , Pregnancy , Humans , Female , Hemangioma/diagnostic imaging , Hemangioma/pathology , Prenatal Care , Prenatal Diagnosis/methods , Fetus/pathology , Ultrasonography, Prenatal/methods
8.
J Colloid Interface Sci ; 583: 89-99, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-32980683

ABSTRACT

Fingerprints are widely studied due to their unique shape and lifelong properties. The latent fingerprint (LFP) visualization is critical in identifying crime scenes and personal information. At present, the powder dusting method for LFP detection is favored due to its environmental friendliness and nontoxicity. However, this method has low resolution, low sensitivity, and large background interference. To address these shortcomings, the red-emitting Sr2MgMoO6:xEu3+ (x = 0-0.50) phosphors were synthesized using the solid-state reaction process. The products were systematically studied through the structural phase, luminescent property, decay curve, and color purity. Sr2MgMoO6:xEu3+ phosphors were monitored at 596 nm and exhibited a commendable broad excitation band between 250 and 475 nm. This result indicated that the disadvantage of the poor absorption of commercial red phosphors (Y2O2S:Eu3+) in the near-ultraviolet region was overcome. Under excitation at 393 nm, the synthesized Sr2MgMoO6:Eu3+ phosphor exhibited intense red light at 596 and 616 nm, due to the 5D0 â†’ 7F1 and 5D0 â†’ 7F2 transitions of Eu3+ ions. The optimal concentration for the Sr2MgMoO6:xEu3+ phosphor was x = 20 mol%, and the concentration quenching effect was ascribed to the dipole-dipole interaction. The Commission International del'Eclairage (CIE) chromaticity coordinates of Sr2MgMoO6:Eu3+ were (0.643, 0.356), and the color purity was 99.8%. Furthermore, the fluorescent LFP images developed by Sr2MgMoO6:0.20Eu3+ phosphors were well visualized, and level 1-3 details were well identified with high resolution, contrast, sensitivity, and selectivity. The obtained results suggested that the Sr2MgMoO6:Eu3+ phosphor can be applied for LFP detection.


Subject(s)
Luminescence , Luminescent Agents , Europium , Light
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117454, 2020 Jan 05.
Article in English | MEDLINE | ID: mdl-31425860

ABSTRACT

Eu3+-doped bismuth lanthanum tungstate BiLaWO6 phosphors were synthesized for the first time by a conventional solid-state reaction at 1273K. By powder X-ray diffraction (XRD), the crystal structure of the phosphor was verified, which revealed its single-phase structure. Under the 467nm wavelength excitation, the Eu3+-doped BiLaWO6 phosphor powders showed red emission (617nm) that was ascribed to the 5D0→7F2 transitions of Eu3+. The effects of concentration on luminescence properties indicated that the optimal doping concentration was x=0.50mol. The thermal stability by the emission intensities at various temperatures was verified, and the activation energy (Ea) was approximately 0.29eV. The luminescence lifetime was analyzed by the decay curve. The chromaticity coordinates of BiLaWO6:0.50Eu3+ were x=0.650, y=0.347, which had a high color purity at 99.2%. The phosphors had potential application for white light-emitting diodes.

10.
Nan Fang Yi Ke Da Xue Xue Bao ; 38(5): 541-546, 2018 May 20.
Article in Zh | MEDLINE | ID: mdl-29891449

ABSTRACT

OBJECTIVE: To investigate the effect of lithium chloride (LiCl) on cell cycle of HK-2 cells and explore the possible pathways involved. METHODS: HK-2 cells were treated with LiCl at different concentrations (5, 12.5, 20, and 25 mmol/L) for 12, 24, 48, or 72 h, and the changes in cell cycle and viability were detected using flow cytometry and CCK-8 assay, respectively. Western blotting was used to analyze the changes in the expressions of cyclin B1 and CDK1 (the two G2 phase-related proteins) and those of AKT/GSK-3ß signaling pathway-related proteins in the treated cells. RESULTS: LiCl treatment time- and concentration-dependently increased HK-2 cell percentage in G2 phase and decreased the cell vitality. The expressions of cyclin B1, CDK1, p-GSK-3ß, and ß-catenin increased and the expression of p-AKT decreased significantly in the cells as LiCl treatment time and concentration increased. CONCLUSION: LiCl may cause HK-2 cell cycle arrest in G2 phase through activation of the AKT/GSK-3ß signaling pathway.


Subject(s)
G2 Phase/drug effects , Glycogen Synthase Kinase 3 beta/metabolism , Lithium Chloride/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , CDC2 Protein Kinase/metabolism , Cell Cycle/drug effects , Cyclin B1/metabolism , Humans , Lithium Chloride/administration & dosage , Signal Transduction , Time Factors , beta Catenin/metabolism
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(6): 833-7, 2016 Jun.
Article in Zh | MEDLINE | ID: mdl-27320888

ABSTRACT

OBJECTIVE: To investigate the effect of arctiin on advanced oxidation protein product (AOPP)-induced epithelial-to-mesenchymal transition (EMT) in tubular cells and explore the mechanisms underlying this effect. METHODS: Human proximal tubular cells (HK-2 cells) were treated with bovine serum albumin (BSA) or AOPPs in the presence or absence of arctiin. The expressions of E-cadherin, vimentin, and GRP78 at the protein and mRNA levels in the cells were examined using Western blotting and quantitative real-time PCR. The level of reactive oxygen species (ROS) was measured by flow cytometry with DCFH-DA as the fluorescent probe. RESULTS: Compared with BSA-treated cells, the cells treated with AOPPs showed decreased expression of epithelial cell marker E-cadherin and overexpression of mesenchymal marker vimentin and endoplasmic reticulum stress marker GRP78 with an increased ROS level. These changes induced by AOPPs were partly inhibited by arctiin. CONCLUSION: Arctiin can ameliorate AOPP-induced EMT in tubular cells by inhibiting endoplasmic reticulum stress, and oxidative stress response may participate in this process.


Subject(s)
Advanced Oxidation Protein Products/adverse effects , Endoplasmic Reticulum Stress , Epithelial-Mesenchymal Transition , Furans/pharmacology , Glucosides/pharmacology , Kidney Tubules/cytology , Antigens, CD , Cadherins/metabolism , Cell Line , Endoplasmic Reticulum Chaperone BiP , Epithelial Cells/cytology , Epithelial Cells/drug effects , Heat-Shock Proteins/metabolism , Humans , Kidney Tubules/drug effects , Oxidative Stress , Reactive Oxygen Species/metabolism , Vimentin/metabolism
12.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(9): 1209-1214, 2016 Aug 20.
Article in Zh | MEDLINE | ID: mdl-27687652

ABSTRACT

OBJECTIVE: To investigate whether the p38 mitogen-activated protein kinase (MAPK) signaling pathway mediates advanced oxidation protein products (AOPPs)-induced epithelial-to-mesenchymal transition (EMT) in tubular cells. METHODS: Human proximal tubular cells (HK-2 cells) exposed to AOPP-bovine serum albumin (BSA) were examined for expressions of p38 MAPK and phosphorylated p38 MAPK using Western blotting. Western blotting and quantitative RT-PCR were used to examine the protein and mRNA expressions of EMT markers E-cadherin and vimentin and endoplasmic reticulum stress marker glucose-regulated protein (GRP) 78 in cells treated with SB203580 (an inhibitor of the p38 MAPK signaling pathway) prior to AOPP exposure. The cells treated with AOPPs following pretreatment with salubrinal (an inhibitor of endoplasmic reticulum stress) were also examined for expressions of p38 MAPK and phosphorylated p38 MAPK. RESULTS: AOPP treatment induced the phosphorylation of p38 MAPK in HK-2 cells. AOPP-induced decrease in E-cadherin expression and overexpression of vimentin and GRP78 were partly inhibited by pretreatment of the cells with SB203580. Salubrina partly suppressed AOPP-induced phosphorylation of p38 MAPK in the cells. CONCLUSION: p38 MAPK signaling pathway, which is regulated by endoplasmic reticulum stress, might mediate AOPP-induced EMT in HK-2 cells.


Subject(s)
Advanced Oxidation Protein Products/metabolism , Epithelial-Mesenchymal Transition , MAP Kinase Signaling System , p38 Mitogen-Activated Protein Kinases/metabolism , Antigens, CD , Cadherins/metabolism , Cell Line , Cinnamates/pharmacology , Endoplasmic Reticulum Chaperone BiP , Endoplasmic Reticulum Stress , Heat-Shock Proteins/metabolism , Humans , Imidazoles/pharmacology , Phosphorylation , Pyridines/pharmacology , Thiourea/analogs & derivatives , Thiourea/pharmacology , Vimentin/metabolism
13.
Chem Commun (Camb) ; 51(56): 11217-20, 2015 Jun 30.
Article in English | MEDLINE | ID: mdl-26077398

ABSTRACT

A facile and efficient catalytic system based on a mesostructured ceria-supported gold (Au/meso-CeO2) catalyst was developed for the synthesis of various aromatic azo compounds by the reductive coupling of the corresponding nitroaromatics, using CO as the sole deoxygenative reagent, under additive-free and mild reaction conditions.


Subject(s)
Azo Compounds/chemical synthesis , Carbon Monoxide/chemistry , Gold/chemistry , Nitro Compounds/chemistry , Oxygen/chemistry , Azo Compounds/chemistry , Catalysis , Molecular Structure
14.
ChemSusChem ; 8(18): 3029-35, 2015 Sep 21.
Article in English | MEDLINE | ID: mdl-26224033

ABSTRACT

Developing new efficient catalytic systems to convert abundant and renewable feedstocks into valuable products in a compact, flexible, and target-specific manner is of high importance in modern synthetic chemistry. Here, we describe a versatile set of mild catalytic conditions utilizing a single gold-based solid catalyst that enables the direct and additive-free preparation of four distinct and important amine derivatives (amines, formamides, benzimidazoles, and dimethlyated amines) from readily available formic acid (FA) and nitro starting materials with high level of chemoselectivity. By controlling the stoichiometry of the employed FA, which has attracted considerable interest in the area of sustainable chemistry because of its potential as an entirely renewable hydrogen carrier and as a versatile C1 source, a facile atom- and step-efficient transformation of nitro compounds can be realized in a modular fashion.

15.
Chem Commun (Camb) ; 50(42): 5626-8, 2014 May 30.
Article in English | MEDLINE | ID: mdl-24728540

ABSTRACT

A new efficient method for chemo- and regio-selective semireduction of alkynes using CO/H2O as the hydrogen source catalyzed by gold supported on high surface area TiO2 was developed. A facile and practical synthesis of 1,2-dideuterioalkenes was also realized by using CO/D2O as the reducing agent.

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