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1.
IEEE Sens J ; 24(5): 6888-6897, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38476583

RESUMO

We developed an ankle-worn gait monitoring system for tracking gait parameters, including length, width, and height. The system utilizes ankle bracelets equipped with wide-angle infrared (IR) stereo cameras tasked with monitoring a marker on the opposing ankle. A computer vision algorithm we have also developed processes the imaged marker positions to estimate the length, width, and height of the person's gait. Through testing on multiple participants, the prototype of the proposed gait monitoring system exhibited notable performance, achieving an average accuracy of 96.52%, 94.46%, and 95.29% for gait length, width, and height measurements, respectively, despite distorted wide-angle images. The OptiGait system offers a cost-effective and user-friendly alternative compared to existing gait parameter sensing systems, delivering comparable accuracy in measuring gait length and width. Notably, the system demonstrates a novel capability in measuring gait height, a feature not previously reported in the literature.

2.
J Am Chem Soc ; 145(13): 7113-7122, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36951270

RESUMO

Cobalt-based catalysts have been widely used for Fischer-Tropsch synthesis (FTS) in industry; however, achieving rational catalyst design at the atomic level and thereby a higher activity and more long-chain-hydrocarbon products simultaneously remain an attractive and difficult challenge. The dual-atomic-site catalysts with unique electronic and geometric interface interactions offer a great opportunity for exploiting advanced FTS catalysts with improved performance. Herein, we designed a Ru1Zr1/Co catalyst with Ru and Zr dual atomic sites on the Co nanoparticle (NP) surface through a metal-organic-framework-mediated synthesis strategy which presents greatly enhanced FTS activity (high turnover frequency of 3.8 × 10-2 s-1 at 200 °C) and C5+ selectivity (80.7%). Control experiments presented a synergic effect between Ru and Zr single-atom site on Co NPs. Further density functional theory calculations of the chain growth process from C1 to C5 revealed that the designed Ru/Zr dual sites remarkably lower the rate-limiting barriers due to the significantly weakened C-O bond and promote the chain growth processes, resulting in the greatly boosted FTS performance. Therefore, our work demonstrates the effectiveness of dual-atomic-site design in promoting the FTS performance and provides new opportunities for developing efficient industrial catalysts.

3.
Prostate ; 83(14): 1387-1392, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37504798

RESUMO

BACKGROUND: Observational studies have shown an association between major depressive disorder (MDD), anxiety, and prostatitis. However, the causal relationship between MDD, anxiety, and prostatitis remains controversial. Therefore, we aimed to use two-sample Mendelian randomization (MR) to assess the causal effects of MDD and anxiety on prostatitis. METHODS: We conducted univariable and multivariable MR analyses using summary statistics from publicly available genome-wide association studies to estimate the causal relationships between MDD, anxiety, and prostatitis risk. In the main MR analysis, the inverse-variance weighted (IVW) method was used, while secondary methods included the weighted median, weighted mode, MR-Egger regression, and MR pleiotropy residual and outlier (MR-PRESSO) tests to detect and correct for the presence of pleiotropy. RESULTS: MDD had 97 independent instrumental variables (IVs) and anxiety had 15 IVs. Univariable MR analysis showed that genetically determined MDD had a detrimental causal effect on prostatitis (IVW: odds ratio [OR] = 1.47, 95% confidence interval [CI] = 1.12-1.92, p = 0.005), while no causal relationship was found between anxiety and prostatitis (IVW: OR = 0.25, 95% CI = 0.02-2.82, p = 0.26). More convincingly, after adjusting for confounding factors such as body mass index, alcohol consumption, and smoking, the genetic liability for MDD remained associated with prostatitis risk, with no strong evidence of anxiety affecting prostatitis incidence. CONCLUSION: This study supports the notion that MDD has a detrimental effect on prostatitis risk, and strategies focused on addressing MDD may be one of the cornerstones for treating prostatitis. The potential preventive value of treating MDD for prostatitis should be further investigated in future research.


Assuntos
Transtorno Depressivo Maior , Prostatite , Masculino , Humanos , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Prostatite/complicações , Prostatite/genética , Ansiedade/genética , Polimorfismo de Nucleotídeo Único
4.
BMC Public Health ; 23(1): 1797, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715140

RESUMO

BACKGROUND: In this study, by analyzing the correlation between various components of health-related physical fitness (HPF) and liver function indicators, the indicators of physical fitness that were highly correlated with liver function and could be monitored at home were screened to prevent more serious liver disease in the future, and to provide experimental basis for prescribing personalized exercise. METHODS: A total of 330 faculties (female = 198) of a university were recruited. The indicators of HPF and liver function were measured. Spearman correlation analysis, multivariate linear regression, and cross-lagged panel model was used to data statistics. RESULTS: In males, body fat (BF) was positively correlated with alanine aminotransferase (ALT); vital capacity and the vital capacity index were positively correlated with albumin; and vertical jump was positively correlated with globulin and negatively correlated with the albumin-globulin ratio (P < 0.05). However, there was no significant correlation among all indicators controlled confounding factors. In females, BF was negatively correlated with direct bilirubin; VO2max was positively correlated with indirect bilirubin; and vertical jump was positively correlated with the albumin-globulin ratio and significantly negatively correlated with globulin (P < 0.05). Controlled confounding factors, body fat percentage was positively correlated with globulin (ß = 0.174) and negatively correlated with direct bilirubin (ß = -0.431), and VO2max was positively correlated with indirect bilirubin (ß = 0.238, P < 0.05). Cross-lagged panel analysis showed that BF percentage can negatively predict direct bilirubin levels with great significance (ß = -0.055, P < 0.05). CONCLUSIONS: HPF may play a crucial role in liver function screening, particularly for female faculty members. For males, BF, vertical jump, vital capacity and vital capacity index could be associated with liver function but are susceptible to complex factors such as age, smoking, diabetes, and hypertension. In females, BF percentage is an important predictor of abnormal liver function in addition to VO2max and vertical jump, which are not affected by complex factors.


Assuntos
Bilirrubina , Aptidão Física , Masculino , Humanos , Feminino , Estudos Transversais , Albuminas , Fígado
5.
Luminescence ; 38(3): 260-268, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36648974

RESUMO

Interactions of human serum albumin (HSA) with two structurally similar quinazoline derivatives, S1 and S2 , which are potential anticancer drugs acting on PI3K/mTOR targets, were investigated in vitro utilizing multiple spectroscopy as well as molecular docking. The fluorescence quenching study demonstrated that HSA fluorescence could be statically quenched by S1 and S2 through the formation of an HSA-drug complex. Furthermore, the details of the binding site number, binding constant, as well as the thermodynamic parameters, were estimated at 298, 303, and 310 K. The results revealed that hydrogen bond interactions, as well as van der Waals forces, were the predominant factors responsible for binding HSA to S1 or S2 . Synchronous fluorescence and ultraviolet (UV) absorption spectra suggested that S1 and S2 had little effect on the polarity of the microenvironment and conformation of HSA. Energy transfer from HSA to S1 or S2 most probably occurred. The docking study revealed that S1 and S2 were able to bind to the hydrophobic cavity that was located in the HSA subdomain IIA and formed varying numbers of hydrogen bonds with amino acid residues nearby. Due to the subtle difference in the chemical structure, the binding of S1 and S2 to HSA was slightly different.


Assuntos
Antineoplásicos , Albumina Sérica Humana , Humanos , Albumina Sérica Humana/química , Fosfatidilinositol 3-Quinases/metabolismo , Simulação de Acoplamento Molecular , Inibidores de MTOR , Ligação Proteica , Espectrometria de Fluorescência , Antineoplásicos/farmacologia , Sítios de Ligação , Serina-Treonina Quinases TOR/metabolismo , Termodinâmica , Dicroísmo Circular
6.
J Appl Clin Med Phys ; 24(7): e14023, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37166416

RESUMO

BACKGROUND: Endoscopic ultrasonography (EUS) is recommended as the best tool for evaluating gastric subepithelial lesions (SELs); nonetheless, it has difficulty distinguishing gastrointestinal stromal tumors (GISTs) from leiomyomas and schwannomas. GISTs have malignant potential, whereas leiomyomas and schwannomas are considered benign. PURPOSE: This study aimed to establish a combined radiomic model based on EUS images for distinguishing GISTs from leiomyomas and schwannomas in the stomach. METHODS: EUS images of pathologically confirmed GISTs, leiomyomas, and schwannomas were collected from five centers. Gastric SELs were divided into training and testing datasets based on random split-sample method (7:3). Radiomic features were extracted from the tumor and muscularis propria regions. Principal component analysis, least absolute shrinkage, and selection operator were used for feature selection. Support vector machine was used to construct radiomic models. Two radiomic models were built: the conventional radiomic model included tumor features alone, whereas the combined radiomic model incorporated features from the tumor and muscularis propria regions. RESULTS: A total of 3933 EUS images from 485 cases were included. For the differential diagnosis of GISTs from leiomyomas and schwannomas, the accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve were 74.5%, 72.2%, 78.7%, and 0.754, respectively, for the EUS experts; 76.8%, 74.4%, 81.0%, and 0.830, respectively, for the conventional radiomic model; and 90.9%, 91.0%, 90.6%, and 0.953, respectively, for the combined radiomic model. For gastric SELs <20 mm, the accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve of the combined radiomic model were 91.4%, 91.6%, 91.1%, and 0.960, respectively. CONCLUSIONS: We developed and validated a combined radiomic model to distinguish gastric GISTs from leiomyomas and schwannomas. The combined radiomic model showed better diagnostic performance than the conventional radiomic model and could assist EUS experts in non-invasively diagnosing gastric SELs, particularly gastric SELs <20 mm.


Assuntos
Tumores do Estroma Gastrointestinal , Leiomioma , Neurilemoma , Neoplasias Gástricas , Humanos , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/patologia , Endossonografia , Neoplasias Gástricas/diagnóstico por imagem , Leiomioma/diagnóstico por imagem , Leiomioma/patologia , Neurilemoma/diagnóstico por imagem , Estômago/patologia
7.
Sensors (Basel) ; 23(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37299826

RESUMO

The preoperative differentiation of breast phyllodes tumors (PTs) from fibroadenomas (FAs) plays a critical role in identifying an appropriate surgical treatment. Although several imaging modalities are available, reliable differentiation between PT and FA remains a great challenge for radiologists in clinical work. Artificial intelligence (AI)-assisted diagnosis has shown promise in distinguishing PT from FA. However, a very small sample size was adopted in previous studies. In this work, we retrospectively enrolled 656 breast tumors (372 FAs and 284 PTs) with 1945 ultrasound images in total. Two experienced ultrasound physicians independently evaluated the ultrasound images. Meanwhile, three deep-learning models (i.e., ResNet, VGG, and GoogLeNet) were applied to classify FAs and PTs. The robustness of the models was evaluated by fivefold cross validation. The performance of each model was assessed by using the receiver operating characteristic (ROC) curve. The area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were also calculated. Among the three models, the ResNet model yielded the highest AUC value, of 0.91, with an accuracy value of 95.3%, a sensitivity value of 96.2%, and a specificity value of 94.7% in the testing data set. In contrast, the two physicians yielded an average AUC value of 0.69, an accuracy value of 70.7%, a sensitivity value of 54.4%, and a specificity value of 53.2%. Our findings indicate that the diagnostic performance of deep learning is better than that of physicians in the distinction of PTs from FAs. This further suggests that AI is a valuable tool for aiding clinical diagnosis, thereby advancing precision therapy.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Fibroadenoma , Tumor Filoide , Médicos , Feminino , Humanos , Tumor Filoide/diagnóstico por imagem , Tumor Filoide/patologia , Estudos Retrospectivos , Fibroadenoma/diagnóstico por imagem , Fibroadenoma/patologia , Inteligência Artificial , Diagnóstico Diferencial , Neoplasias da Mama/diagnóstico por imagem
8.
J Environ Manage ; 345: 118810, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37595461

RESUMO

Vegetation concrete has been widely applied for the ecological restoration of bare steep slopes in short-term frozen and non-frozen soil regions in China. However, field experiments conducted in seasonally frozen soil regions have revealed decreases in the bulk density, nutrient content and vegetation coverage. This study aimed to clarify the evolution process and mechanism of the engineering properties of vegetation concrete under atmospheric freeze-thaw (F-T) test conditions. The physical, mechanical, and nutrient properties of vegetation concrete were investigated using six F-T cycles (0, 1, 2, 5, 10 and 20) and two initial soil water contents (18 and 22%). The results revealed decreases in the acoustic wave velocity and cohesive forces and an increase in the permeability coefficient of the vegetation concrete owing to F-T action. X-ray diffraction tests indicated that the decreased cohesive force was closely related to the overall decrease in the content of gelling hydration products in the vegetation concrete. Additionally, the contents of NH4+-N, PO43-P and K+ in the vegetation concrete increased, whereas that of NO3--N decreased. The loss rates of these soluble nutrients increased, indicating that the nutrient retention capacity of the vegetation concrete had decreased. Specifically, the decreased nutrient retention capacity was mainly related to the disintegration and fragmentation of larger aggregates due to F-T action. This study provides theoretical support for future research on improving the anti-freezing capability of ecological slope protection substrates in seasonally frozen soil regions.


Assuntos
Solo , Água , Solo/química , Clima , Engenharia , China
9.
Pak J Pharm Sci ; 36(5): 1527-1542, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37869929

RESUMO

S1 and S2, two structurally similar quinazoline derivatives, are novel anticancer drugs targeting the PI3K/AKT/mTOR signaling pathway channel. However, their pharmacokinetic and tissue distribution characteristics are unknown, which has hindered further development and in-depth studies. In this study, a simple, rapid and sensitive method using high performance liquid chromatography was established and validated to quantitatively study the pharmacokinetics and tissue distribution profiles of S1 and S2 in rats following intravenous injection. The results indicated that after intravenous injection, the elimination of S1 and S2 fit the two-compartment model and linear pharmacokinetics characteristics were observed. Furthermore, S1 and S2 were widely distributed and found in high concentrations in liver and kidney tissues and a small proportion of S1 and S2 could cross the blood-brain barrier and be distributed in the brain. The current findings will contribute to interpretation and understanding the relationship between dosage and pharmacodynamic effects of S1 and S2.


Assuntos
Antineoplásicos , Quinazolinas , Animais , Ratos , Antineoplásicos/farmacocinética , Inibidores de MTOR/farmacocinética , Quinazolinas/farmacocinética , Distribuição Tecidual , Serina-Treonina Quinases TOR/antagonistas & inibidores , Inibidores de Fosfoinositídeo-3 Quinase/farmacocinética
10.
Mol Cancer ; 21(1): 37, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35130920

RESUMO

PURPOSE: The overall response of cisplatin-based chemotherapy in bladder urothelial carcinoma (BUC) remains unsatisfactory due to the complex pathological subtypes, genomic difference, and drug resistance. The genes that associated with cisplatin resistance remain unclear. Herein, we aimed to identify the cisplatin resistance associated genes in BUC. EXPERIMENTAL DESIGN: The cytotoxicity of cisplatin was evaluated in six bladder cancer cell lines to compare their responses to cisplatin. The T24 cancer cells exhibited the lowest sensitivity to cisplatin and was therefore selected to explore the mechanisms of drug resistance. We performed genome-wide CRISPR screening in T24 cancer cells in vitro, and identified that the gene heterogeneous nuclear ribonucleoprotein U (HNRNPU) was the top candidate gene related to cisplatin resistance. Epigenetic and transcriptional profiles of HNRNPU-depleted cells after cisplatin treatment were analyzed to investigate the relationship between HNRNPU and cisplatin resistance. In vivo experiments were also performed to demonstrate the function of HNRNPU depletion in cisplatin sensitivity. RESULTS: Significant correlation was found between HNRNPU expression level and sensitivity to cisplatin in bladder cancer cell lines. In the high HNRNPU expressing T24 cancer cells, knockout of HNRNPU inhibited cell proliferation, invasion, and migration. In addition, loss of HNRNPU promoted apoptosis and S-phase arrest in the T24 cells treated with cisplatin. Data from The Cancer Genome Atlas (TCGA) demonstrated that HNRNPU expression was significantly higher in tumor tissues than in normal tissues. High HNRNPU level was negatively correlated with patient survival. Transcriptomic profiling analysis showed that knockout of HNRNPU enhanced cisplatin sensitivity by regulating DNA damage repair genes. Furthermore, it was found that HNRNPU regulates chemosensitivity by affecting the expression of neurofibromin 1 (NF1). CONCLUSIONS: Our study demonstrated that HNRNPU expression is associated with cisplatin sensitivity in bladder urothelial carcinoma cells. Inhibition of HNRNPU could be a potential therapy for cisplatin-resistant bladder cancer.


Assuntos
Antineoplásicos , Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Carcinoma de Células de Transição/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo U , Humanos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
11.
Eur Radiol ; 32(3): 1590-1600, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34519862

RESUMO

OBJECTIVE: Sonographic features are associated with pathological and immunohistochemical characteristics of triple-negative breast cancer (TNBC). To predict the biological property of TNBC, the performance using quantitative high-throughput sonographic feature analysis was compared with that using qualitative feature assessment. METHODS: We retrospectively reviewed ultrasound images, clinical, pathological, and immunohistochemical (IHC) data of 252 female TNBC patients. All patients were subgrouped according to the histological grade, Ki67 expression level, and human epidermal growth factor receptor 2 (HER2) score. Qualitative sonographic feature assessment included shape, margin, posterior acoustic pattern, and calcification referring to the Breast Imaging Reporting and Data System (BI-RADS). Quantitative sonographic features were acquired based on the computer-aided radiomics analysis. Breast cancer masses were manually segmented from the surrounding breast tissues. For each ultrasound image, 1688 radiomics features of 7 feature classes were extracted. The principal component analysis (PCA), least absolute shrinkage and selection operator (LASSO), and support vector machine (SVM) were used to determine the high-throughput radiomics features that were highly correlated to biological properties. The performance using both quantitative and qualitative sonographic features to predict biological properties of TNBC was represented by the area under the receiver operating characteristic curve (AUC). RESULTS: In the qualitative assessment, regular tumor shape, no angular or spiculated margin, posterior acoustic enhancement, and no calcification were used as the independent sonographic features for TNBC. Using the combination of these four features to predict the histological grade, Ki67, HER2, axillary lymph node metastasis (ALNM), and lymphovascular invasion (LVI), the AUC was 0.673, 0.680, 0.651, 0.587, and 0.566, respectively. The number of high-throughput features that closely correlated with biological properties was 34 for histological grade (AUC 0.942), 27 for Ki67 (AUC 0.732), 25 for HER2 (AUC 0.730), 34 for ALNM (AUC 0.804), and 34 for LVI (AUC 0.795). CONCLUSION: High-throughput quantitative sonographic features are superior to traditional qualitative ultrasound features in predicting the biological behavior of TNBC. KEY POINTS: • Sonographic appearances of TNBCs showed a great variety in accordance with its biological and clinical characteristics. • Both qualitative and quantitative sonographic features of TNBCs are associated with tumor biological characteristics. • The quantitative high-throughput feature analysis is superior to two-dimensional sonographic feature assessment in predicting tumor biological property.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Metástase Linfática , Curva ROC , Estudos Retrospectivos , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Ultrassonografia
12.
J Exerc Sci Fit ; 20(4): 355-365, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36186829

RESUMO

Objectives: The present study aimed to examine the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on visceral fat and hemodynamic parameters in obese adults. Methods: Fifty-two males were included in this study and divided into three groups: HIIT group (n = 21, age = 20.86 ± 1.62 years, BF (%) = 30.10 ± 5.02), MICT group (n = 22, age = 20.76 ± 1.14 years, BF (%) = 30.19 ± 5.76), and control group (CON) (n = 9, age = 21.38 ± 1.77 years, BF (%) = 30.40 ± 5.10). The HIIT and MICT groups received the exercise intervention three to four times per week for eight weeks (HIIT: exercise intensity 80-95% HRmax, circuit; MICT: exercise intensity 60-70% HRmax, running), and the control (CON) group received health education and guidance without exercise intervention. The body compositions and serum lipid indexes were tested to calculated LAP and VAI. The color doppler ultrasound diagnostic technology was used to test the artery diameter and blood velocity before and after the intervention. Based on the test data, MATLAB software and Womersley theory were used to calculate the hemodynamic parameters of the common carotid artery, including wall shear stress, flow rate, blood pressure, oscillatory shear index, elasticity modulus, dynamic resistance, artery diameter, arterial stiffness, circumferential strain and pulsatility index. Results: We found that lipid accumulation product (LAP) was significantly decreased in both the HIIT group (p < 0.01) and MICT (p < 0.05) group but not in the CON group (p > 0.05). In contrast, visceral adiposity index (VAI) decreased in both the HIIT and MICT groups and increased in the CON group, although the difference among groups was not significant (p > 0.05). After 8 weeks of intervention, the blood velocity and wall shear stress were greater after HIIT and MICT intervention (p < 0.01). Artery diameter, oscillatory shear index, arterial stiffness, and pulsatility index decreased significantly, and circumferential strain increased significantly in the HIIT group (all, p < 0.01, p < 0.05) but not in the MICT group (p > 0.05). Dynamic resistance was significantly decreased in the MICT group. There was no difference in the CON group after the period of intervention (all, p > 0.05). LAP was positively related to artery diameter (r = 0.48, p = 0.011), blood pressure (r = 0.46, p = 0.002), flow rate (r = 0.31, p = 0.04), oscillatory shear index (r = 0.44, p = 0.03), and elasticity modulus (r = 0.33, p = 0.029) but inversely related to circumferential strain (r = -0.36, p = 0.028). The VAI was also positively associated with artery diameter (r = 0.33, p = 0.03), elasticity modulus (r = 0.38, p = 0.009), and arterial stiffness (r = 0.39, p = 0.012). In addition, the VAI was negatively correlated with the circumferential strain (r = -0.33, p = 0.04). Conclusion: The present study demonstrated that both HIIT and MICT exercises for 8 weeks could effectively enhance visceral fat indices and partial hemodynamic parameters. Therefore, HIIT and MICT exert important effects on reducing fat content and improving hemodynamic environment. But HIIT on oscillatory shear index, arterial stiffness, circumferential strain, and pulsatility index was superior to MICT. In addition, there are close correlations between visceral fat and partial hemodynamic parameters of the common carotid artery.

13.
Rare Metals ; 41(7): 2129-2152, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35291268

RESUMO

CO2-assisted oxidative dehydrogenation of propane (CO2-ODHP) is an attractive strategy to offset the demand gap of propylene due to its potentiality of reducing CO2 emissions, especially under the demands of peaking CO2 emissions and carbon neutrality. The introduction of CO2 as a soft oxidant into the reaction not only averts the over-oxidation of products, but also maintains the high oxidation state of the redox-active sites. Furthermore, the presence of CO2 increases the conversion of propane by coupling the dehydrogenation of propane (DHP) with the reverse water gas reaction (RWGS) and inhibits the coking formation to prolong the lifetime of catalysts via the reverse Boudouard reaction. An effective catalyst should selectively activate the C-H bond but suppress the C-C cleavage. However, to prepare such a catalyst remains challenging. Chromium-based catalysts are always applied in industrial application of DHP; however, their toxic properties are harmful to the environment. In this aspect, exploring environment-friendly and sustainable catalytic systems with Cr-free is an important issue. In this review, we outline the development of the CO2-ODHP especially in the last ten years, including the structural information, catalytic performances, and mechanisms of chromium-free metal-based catalyst systems, and the role of CO2 in the reaction. We also present perspectives for future progress in the CO2-ODHP.

14.
Anal Chem ; 93(33): 11379-11387, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34378378

RESUMO

This work presents a sensitive and specific single-step RNA sensor for Zika virus (ZIKV) in serum. Using AC electrokinetics (ACEK)-enhanced capacitive sensing technology, ZIKV genomic RNA (gRNA) can be directly detected from serum. The sensors are interdigitated electrodes modified with oligonucleotide probes complementary to the conserved regions of ZIKV gRNA. The ACEK capacitive sensing applies an optimized AC excitation signal over the sensor, which induces ACEK microfluidic enrichment of analytes and also simultaneously performs real-time monitoring of hybridization of ZIKV gRNA on the sensor surface. Hence, the sensing procedures are simple with rapid turn-around time and good specificity and sensitivity. A series of experiments are conducted to optimize the sensor performance. The performance of the sensor is investigated for three different probes, two functionalization buffers, and different hybridization buffers. With the optimized sensing protocol, this method can detect spiked ZIKV gRNA from human serum within 30 s and reach a limit of detection of 78.8 copies/µL in analytical samples and as low as 287.5 copies/µL in neat serum. The sensors can successfully differentiate between the RNAs of the ZIKV and dengue virus, two viruses with similar transmission paths and symptoms. The sensor is simple to use and requires no labeling or sophisticated process typically involved in a polymerase chain reaction, hybridization chain reaction, or nucleic acid sequence-based amplification.


Assuntos
Infecção por Zika virus , Zika virus , Genômica , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , RNA Viral/genética , Sensibilidade e Especificidade , Zika virus/genética , Infecção por Zika virus/diagnóstico
15.
Ultrason Imaging ; 43(1): 19-28, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33355516

RESUMO

It is of vital importance to identify the pleural line when performing lung ultrasound, as the pleural line not only indicates the interface between the chest wall and lung, but offers additional diagnostic information. In the current clinical practice, the pleural line is visually detected and evaluated by clinicians, which requires experiences and skills with challenges for the novice. In this study, we developed a computer-aided technique for automated pleural line detection using ultrasound. The method first utilized the Radon transform to detect line objects in the ultrasound images. The relation of the body mass index and chest wall thickness was then applied to estimate the range of the pleural thickness, based on which the pleural line was detected together with the consideration of the ultrasonic properties of the pleural line. The proposed method was validated by testing 83 ultrasound data sets collected from 21 pneumothorax patients. The pleural lines were successfully identified in 76 data sets by the automated method (successful detection rate 91.6%). In those successful cases, the depths of the pleural lines measured by the automated method agreed with those manually measured as confirmed with the Bland-Altman test. The measurement errors were below 5% in terms of the pleural line depth. As a conclusion, the proposed method could detect the pleural line in an automated manner in the defined data set. In addition, the method may potentially act as an alternative to visual inspection after further tests on more diverse data sets are performed in future studies.


Assuntos
Radônio , Humanos , Ultrassonografia
16.
Ultrason Imaging ; 43(6): 308-319, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34470531

RESUMO

Large scale early scanning of fetuses via ultrasound imaging is widely used to alleviate the morbidity or mortality caused by congenital anomalies in fetal hearts and lungs. To reduce the intensive cost during manual recognition of organ regions, many automatic segmentation methods have been proposed. However, the existing methods still encounter multi-scale problem at a larger range of receptive fields of organs in images, resolution problem of segmentation mask, and interference problem of task-irrelevant features, obscuring the attainment of accurate segmentations. To achieve semantic segmentation with functions of (1) extracting multi-scale features from images, (2) compensating information of high resolution, and (3) eliminating the task-irrelevant features, we propose a multi-scale model with skip connection framework and attention mechanism integrated. The multi-scale feature extraction modules are incorporated with additive attention gate units for irrelevant feature elimination, through a U-Net framework with skip connections for information compensation. The performance of fetal heart and lung segmentation indicates the superiority of our method over the existing deep learning based approaches. Our method also shows competitive performance stability during the task of semantic segmentations, showing a promising contribution on ultrasound based prognosis of congenital anomaly in the early intervention, and alleviating the negative effects caused by congenital anomaly.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Coração Fetal/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Ultrassonografia
17.
Int J Mol Sci ; 22(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361032

RESUMO

17,18-Epoxyeicosatetraenoic acid (17,18-EEQ) and 19,20-epoxydocosapentaenoic acid (19,20-EDP) are bioactive epoxides produced from n-3 polyunsaturated fatty acid eicosapentaenoic acid and docosahexaenoic acid, respectively. However, these epoxides are quickly metabolized into less active diols by soluble epoxide hydrolase (sEH). We have previously demonstrated that an sEH inhibitor, t-TUCB, decreased serum triglycerides (TG) and increased lipid metabolic protein expression in the brown adipose tissue (BAT) of diet-induced obese mice. This study investigates the preventive effects of t-TUCB (T) alone or combined with 19,20-EDP (T + EDP) or 17,18-EEQ (T + EEQ) on BAT activation in the development of diet-induced obesity and metabolic disorders via osmotic minipump delivery in mice. Both T + EDP and T + EEQ groups showed significant improvement in fasting glucose, serum triglycerides, and higher core body temperature, whereas heat production was only significantly increased in the T + EEQ group. Moreover, both the T + EDP and T + EEQ groups showed less lipid accumulation in the BAT. Although UCP1 expression was not changed, PGC1α expression was increased in all three treated groups. In contrast, the expression of CPT1A and CPT1B, which are responsible for the rate-limiting step for fatty acid oxidation, was only increased in the T + EDP and T + EEQ groups. Interestingly, as a fatty acid transporter, CD36 expression was only increased in the T + EEQ group. Furthermore, both the T + EDP and T + EEQ groups showed decreased inflammatory NFκB signaling in the BAT. Our results suggest that 17,18-EEQ or 19,20-EDP combined with t-TUCB may prevent high-fat diet-induced metabolic disorders, in part through increased thermogenesis, upregulating lipid metabolic protein expression, and decreasing inflammation in the BAT.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Ácidos Araquidônicos/uso terapêutico , Benzoatos/uso terapêutico , Obesidade/tratamento farmacológico , Compostos de Fenilureia/uso terapêutico , Adipogenia , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Animais , Fármacos Antiobesidade/administração & dosagem , Fármacos Antiobesidade/farmacologia , Ácidos Araquidônicos/administração & dosagem , Ácidos Araquidônicos/farmacologia , Benzoatos/administração & dosagem , Benzoatos/farmacologia , Glicemia/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , Dieta Hiperlipídica , Epóxido Hidrolases/antagonistas & inibidores , Ácidos Graxos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Obesidade/etiologia , Obesidade/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/farmacologia
18.
Ultrason Imaging ; 42(3): 148-158, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32238107

RESUMO

Because of continuous movement and variation in diameter of the inferior vena cava (IVC) with respiration, the measurements on IVC are labor-intensive and with considerable inter-operator variations. Some computer-assisted techniques have been developed to track the movement of the IVC semi-automatically. However, existing methods predominantly rely on reference marker selection and require many manual inputs. In this study, we developed a cross-correlation (CC)-based method for automated IVC movement tracking and measurement, which requires minimal manual input and avoids manual selection of reference markers. Based on the CC method, two approaches, named direct and relative approaches, were used to calculate the maximum, minimum, and variation of the IVC diameter, and compared with the manual measurement. Fifty-four ultrasound cine-loops collected from nine pigs were tested. The results reveal that both the proposed approaches were well agreed with the manual measurement. The errors of the direct approach were less than 9%, while those of relative approach were as high as 26.7%. It is concluded that the proposed direct approach is superior for IVC diameter measurements, which can be comparable with manual counterpart, serving as an alternative to traditional IVC measurement.


Assuntos
Ultrassonografia/métodos , Veia Cava Inferior/anatomia & histologia , Animais , Feminino , Processamento de Imagem Assistida por Computador , Modelos Animais , Suínos
19.
Electrophoresis ; 40(6): 890-896, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30132934

RESUMO

A rapid, low-cost, highly sensitive, and specific capacitive aptasensor is presented for detection of lipopolysaccharides (LPS). Exposure to LPS could cause fever, gram-negative sepsis, septic shock, and eventual death. Hence, rapid, low cost, and sensitive detection of LPS is pivotal for the safety of food, pharmaceutical, and medical devices and products. In this work, a capacitive sensing method based on alternating current electrokinetics is developed to achieve rapid and specific detection of LPS. This method uses an alternating current signal for two purposes. One is to induce positive dielectrophoresis, which attracts LPS toward the sensor electrodes' surface and accelerates its binding with the immobilized aptamer probe. The other purpose is to simultaneously sense the binding reaction by measuring the interfacial capacitance change on the electrodes' surface. The testing procedures and instrumentation setup of this sensing platform are significantly simplified while finding quantitative concentrations of both analytical and complex samples within 30 s. When testing analytical samples of LPS from Escherichia coli O55:B5, a LOD of 4.93 fg/mL is achieved. The recovery analysis is also performed with LPS spiked in a complex matrix and good recovery rates are demonstrated. This work provides an affordable and field-deployable platform for highly sensitive and real-time LPS detection.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Análise de Alimentos/métodos , Lipopolissacarídeos/análise , Sondas Moleculares/química , Escherichia coli/química , Escherichia coli/isolamento & purificação , Limite de Detecção
20.
Langmuir ; 35(21): 7018-7025, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31066285

RESUMO

There is a growing interest in the use of hybrid liposomes for various biochemical and biomedical applications. In this study, we report the first preparation and characterization of a class of TiO2-reinforced liposomes by a one-step assembly approach. The amphiphilic natural structure of lipids is exploited to localize a hydrophobic molecule, namely, precursor tetrabutyl titanate (TBOT), in the mid-plane of the liposomal bilayer assemblies in the aqueous phase. In situ TiO2 nanoshell formation is driven by subsequent interfacial hydrolysis of TBOT and the ensuing condensation within the hydrophobic interstices of the lipid bilayer. The core-shell structure, like cell and wall, is demonstrated by means of scanning electron microscopy and transmission electron microscopy images, and the formation of the TiO2 shell is confirmed using energy-dispersive X-ray spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. To study the structural evolution of the hybrid liposomes during titania formation, fluorescence probe technique and surface pressure versus molecular area (π- A) isotherms are designed. The results demonstrate that the incorporation of TBOT into the mid-membrane of the lipid and titania in the core of the membrane strengthened the assembly of the lipid bilayer. We further demonstrate that titania shell improved the stability and release property of liposomes. We expect that the reported new TiO2-coated liposomes by co-assembly will be valuable in designing hybrid liposomes, exhibiting integrative capacity for drug encapsulation, compartment reaction, and photocatalysis.


Assuntos
Bicamadas Lipídicas/química , Nanoestruturas , Titânio/química , Interações Hidrofóbicas e Hidrofílicas , Lipossomos , Microscopia Eletrônica de Varredura , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Espectrometria por Raios X
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