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1.
J Agric Food Chem ; 72(20): 11308-11320, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38720452

RESUMO

The dearomatization at the hydrophobic tail of the boscalid was carried out to construct a series of novel pyrazole-4-carboxamide derivatives containing an oxime ether fragment. By using fungicide-likeness analyses and virtual screening, 24 target compounds with theoretical strong inhibitory effects against fungal succinate dehydrogenase (SDH) were designed and synthesized. Antifungal bioassays showed that the target compound E1 could selectively inhibit the in vitro growth of R. solani, with the EC50 value of 1.1 µg/mL that was superior to that of the agricultural fungicide boscalid (2.2 µg/mL). The observations by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) demonstrated that E1 could reduce mycelial density and significantly increase the mitochondrial number in mycelia cytoplasm, which was similar to the phenomenon treated with boscalid. Enzyme activity assay showed that the E1 had the significant inhibitory effect against the SDH from R. solani, with the IC50 value of 3.3 µM that was superior to that of boscalid (7.9 µM). The mode of action of the target compound E1 with SDH was further analyzed by molecular docking and molecular dynamics simulation studies. Among them, the number of hydrogen bonds was significantly more in the SDH-E1 complex than that in the SDH-boscalid complex. This research on the dearomatization strategy of the benzene ring for constructing pyrazole-4-carboxamides containing an oxime ether fragment provides a unique thought to design new antifungal drugs targeting SDH.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos , Fungicidas Industriais , Oximas , Pirazóis , Succinato Desidrogenase , Succinato Desidrogenase/antagonistas & inibidores , Succinato Desidrogenase/química , Succinato Desidrogenase/metabolismo , Pirazóis/química , Pirazóis/farmacologia , Pirazóis/síntese química , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Fungicidas Industriais/síntese química , Relação Estrutura-Atividade , Oximas/química , Oximas/farmacologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Proteínas Fúngicas/química , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/metabolismo , Simulação de Acoplamento Molecular , Rhizoctonia/efeitos dos fármacos , Éteres/química , Éteres/farmacologia , Estrutura Molecular
2.
Artigo em Inglês | MEDLINE | ID: mdl-38686814

RESUMO

OBJECTIVE: To explore the relationship between two-year changes in muscle strength and cartilage according to knee pain in mild and moderate knee Osteoarthritis (OA). DESIGN: 279 participants were retrospectively obtained from the Osteoarthritis Initiative. Western Ontario McMaster University (WOMAC) and Knee Injury and Osteoarthritis Outcome Score were used to assess pain and function. Five muscles strength (maximum extensor and flexor, normalized maximum extensor and flexor, and extensor/flexor ratio) were measured from isometric strength test. Menisci and cartilage volumes were measured from MRI to assess two-year of OA progression. RESULTS: Mild and moderate knee OA progression was characterized by patellofemoral cartilage loss and meniscal degeneration. For WOMAC pain >2 participants, decrease in extensor strength and normalized extensor strength were positively correlated with medial meniscus volume loss (r = 0.261, P = 0.021; r = 0.232, P = 0.041, respectively). The extensor/flexor ratio changes were positively associated with WOMAC function changes (r = 0.291, P = 0.013) over two-year. CONCLUSION: The study observed a positive correlation between quadriceps strength decrease and medial meniscus degeneration in mild and moderate knee OA patients with WOMAC pain >2. These findings suggested quadriceps-hamstrings balance possibly plays a protective role in knee function for participants with weaker quadriceps and severe pain.

3.
Mol Divers ; 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38609691

RESUMO

4-Hydroxyphenylpyruvate dioxygenase (EC 1.13.11.27; HPPD) is one of the important target enzymes in the development of herbicides. To discover novel HPPD inhibitors with unique molecular, 39 cyclohexanedione derivations containing pyrazole and pyridine groups were designed and synthesized. The preliminary herbicidal activity test results showed that some compounds had obvious inhibitory effects on monocotyledon and dicotyledonous weeds. The herbicidal spectrums of the highly active compounds were further determined, and the compound G31 exhibited the best inhibitory rate over 90% against Plantago depressa Willd and Capsella bursa-pastoris at the dosages of 75.0 and 37.5 g ai/ha, which is comparable to the control herbicide mesotrione. Moreover, compound G31 showed excellent crop safety, with less than or equal to 10% injury rates to corn, sorghum, soybean and cotton at a dosage of 225 g ai/ha. Molecular docking and molecular dynamics simulation analysis revealed that the compound G31 could stably bind to Arabidopsis thaliana HPPD (AtHPPD). This study indicated that the compound G31 could be used as a lead molecular structure for the development of novel HPPD inhibitors, which provided an idea for the design of new herbicides with unique molecular scaffold.

4.
Acad Radiol ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38472024

RESUMO

RATIONALE AND OBJECTIVES: To assess image quality, contrast volume and radiation dose reduction potential and diagnostic performance with the use of high-strength deep learning image reconstruction (DLIR-H) in transcatheter aortic valve implantation (TAVI) planning CT. METHODS: We prospectively enrolled 128 patients referred to TAVI-planning CT. Patients were randomly divided into two groups: DLIR-H group (n = 64) and conventional group (n = 64). The DLIR-H group was scanned with tube voltage of 80kVp and body weighted-dependent contrast injection rate of 28mgI/kg/s, images reconstructed using DLIR-H; the conventional group was scanned with 100kVp and contrast injection rate of 40mgI/kg/s, and images reconstructed using adaptive statistical iterative reconstruction-V at 50% (ASIR-V 50%). Radiation dose, contrast volume, contrast injection rate, and image quality were compared between the two groups. The diagnostic performance of TAVI planning CT for coronary stenosis in 115 patients were calculated using invasive coronary angiography as golden standard. RESULTS: DLIR-H group significantly reduced radiation dose (4.94 ± 0.39mSv vs. 7.93 ± 1.20mSv, p < 0.001), contrast dose (45.28 ± 5.38 mL vs. 63.26 ± 9.88 mL, p < 0.001), and contrast injection rate (3.1 ± 0.31 mL/s vs. 4.9 ± 0.2 mL/s, p < 0.001) compared to the conventional group. Images in DLIR-H group had significantly higher SNR and CNR (all p < 0.001). For the diagnostic performance on a per-patient basis, TAVI planning CT in the DLIR-H group provided 100% sensitivity, 92.1% specificity, 100% negative predictive value (NPV), and 84.2% positive predictive value for the detection of > 50% stenosis. In the conventional group, the corresponding results were 94.7%, 95.3%, 97.6%, and 90.0%, respectively. CONCLUSION: DLIR-H in TAVI-planning CT provides improved image quality with reduced radiation and contrast doses, and enables satisfactory diagnostic performance for coronary arteries stenosis.

5.
Quant Imaging Med Surg ; 14(2): 1860-1872, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38415146

RESUMO

Background: For patients with suspected simultaneous coronary and cerebrovascular atherosclerosis, conventional single-site computed tomography angiography (CTA) for both sites can result in nonnegligible radiation and contrast agent dose. The purpose of this study was to validate the feasibility of one-stop coronary and carotid-cerebrovascular CTA (C&CC-CTA) with a "double-low" (low radiation and contrast) dose protocol reconstructed with deep learning image reconstruction with high setting (DLIR-H) algorithm. Methods: From February 2018 to January 2019, 60 patients referred to C&CC-CTA simultaneously in West China Hospital were recruited in this prospective cohort study. By random assignment, patients were divided into two groups: double-low dose group (n=30) used 80 kVp and 24 mgI/kg/s contrast dose with images reconstructed using DLIR-H; and routine-dose group (n=30) used 100 kVp and 32 mgI/kg/s contrast dose with images reconstructed using 50% adaptive statistical iterative reconstruction-V (ASIR-V50%). Radiation and contrast doses, subjective image quality score, CT attenuation values, noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured and compared between the groups. Results: The DLIR-H group used 30% less contrast dose (35.80±4.85 vs. 51.13±6.91 mL) and 48% less overall radiation dose (1.00±0.09 vs. 1.91±0.42 mSv) than the ASIR-V50% group (both P<0.001). There was no statistically significant difference on subjective quality score between the two groups (C-CTA: 4.38±0.67 vs. 4.17±0.81, P=0.337 and CC-CTA: 4.18±0.87 vs. 4.08±0.79, P=0.604). For coronary CTA, lower background noise (18.93±1.43 vs. 22.86±3.75 HU) was reached in DLIR-H group, and SNR and CNR at all assessed branches were significantly increased compared to ASIR-V50% group (all P<0.05), except SNR of left anterior descending (P>0.05). For carotid-cerebrovascular CTA, DLIR-H group was comparable in background noise (19.25±1.42 vs. 20.23±2.40 HU), SNR and CNR at all assessed branches with ASIR-V50% group (all P>0.05). Conclusions: The "double-low" dose one-stop C&CC-CTA with DLIR-H obtained higher image quality compared with the routine-dose protocol with ASIR-V50% while achieving 48% and 30% reduction in radiation and contrast dose, respectively.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38206636

RESUMO

OBJECTIVE: To assess the relationship between walking exercise and medial joint space narrowing (JSN) progression, symptoms, and knee extensor muscle strength (EMS) in early knee osteoarthritis (OA) patients. METHODS: This nested cohort study within the Osteoarthritis Initiative included participants aged 50 and above with knee OA (Kellgren-Lawrence grades 0-2). Walking exercisers were identified using a modified Historical Physical Activity Survey Instrument. Differences in medial JSN, Knee Injury and Osteoarthritis Outcome Score (KOOS), and knee EMS were evaluated through the three-way ANOVA. RESULTS: Among 896 participants, 83.4% reported walking exercise. Female walkers showed significant improvements in symptoms (KOOS-Pain: P < 0.001; KOOS-Symptom: P < 0.001; KOOS-Quality of Life (QOL): P < 0.001; KOOS-Function, Sports, and Recreational Activities (FSR): P = 0.007). Similar results were observed in male walkers (KOOS-Pain: P < 0.001; KOOS-Symptom: P < 0.001; KOOS- QOL: P = 0.001; KOOS- FSR: P = 0.009). Walkers showed significantly increased knee EMS at 24 months (Female: P < 0.001; Male: P = 0.003). Female non-walkers had significantly decreased knee EMS at 24 months (P < 0.001). Walkers showed significant improvement in medial JSN (OR = 1.1, 95% CI: 1.0 to 1.2) and KL grade (OR = 1.0, 95% CI: 1.0 to 1.1) compared to non-walkers. CONCLUSION: Walking exercise prevents structural progression and improves symptoms. Meanwhile, the increased knee EMS in all walkers further supports the validity of recommending walking exercises for early-stage knee OA patients.

7.
J Comput Assist Tomogr ; 47(6): 898-905, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37948364

RESUMO

OBJECTIVE: This study aimed to evaluate the clinical performance of a deep learning-based motion correction algorithm (MCA) in projection domain for coronary computed tomography angiography (CCTA). METHODS: A total of 192 patients who underwent CCTA examinations were included and divided into 2 groups based on the average heart rate (HR): group 1, 82 patients with HR of <75 beats per minute; group 2, 110 patients with HR of ≥75 beats per minute. The CCTA images were reconstructed with and without MCA. The subjective image quality was graded in terms of vessel visualization, sharpness, diagnostic confidence, and overall image quality using a 5-point scale, where cases with all scores of ≥3 were deemed interpretable. Objective image quality was measured through signal-to-noise ratio and contrast-to-noise ratio in regions relative to the vessels. The image quality scores for 2 reconstructions and effective dose between 2 groups were compared. RESULTS: The mean effective dose was similar between 2 groups. Neither group showed significant difference on objective image quality for 2 reconstructions. Images reconstructed with and without MCA were both found interpretable for group 1, whereas the subjective image quality was significantly improved by the MCA for all 4 metrics in group 2, with the interpretability increased from 80.91% to 99.09%. Compared with group 1, group 2 showed similar interpretability and diagnostic confidence, despite inferior overall image quality. CONCLUSIONS: In CCTA examinations, the deep learning-based MCA is capable of improving the image quality and diagnostic confidence for patients with increased HR to a similar level as for those with low HR.


Assuntos
Angiografia por Tomografia Computadorizada , Aprendizado Profundo , Humanos , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Frequência Cardíaca/fisiologia , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Doses de Radiação
8.
Sensors (Basel) ; 23(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38005588

RESUMO

A hydrogen maser is a high-precision time measurement instrument with high frequency stability and low frequency drift, which is widely used in satellite navigation, ground time keeping, frequency measurement, and other fields. An active hydrogen maser (AHM) is better than the current space passive hydrogen maser (PHM) in orbit in terms of its frequency stability and drift rate, but it has the disadvantages of large volume and weight. To further reduce the volume and weight of the circuit, this paper demonstrates a digital circuit control system based on a field-programmable gate array (FPGA). It uses digital temperature control, digital detectors, digital down-conversion, digital phase-locked loops, and other digital methods for temperature control, cavity auto-tuning, and crystal phase locking, which improve the integration and flexibility of the circuit system. Meanwhile, a tuning method based on hydrogen flow is proposed, which effectively solves the problem of fluctuations in hydrogen maser resonance frequency with changes in the external environment. Our experimental results show that the designed digital circuit control system meets the requirements of an oven-controlled crystal oscillator (OCXO) loop and a cavity loop. Its frequency stability can reach 2.6×10-13/1 s and 1.4×10-15/10,000 s, which is close to the stability index of ground active hydrogen maser. This scheme has certain practical engineering value, and can be used in the design of hydrogen masers for next-generation space navigation satellites, deep space exploration, and space stations.

9.
Eur J Radiol ; 168: 111141, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832197

RESUMO

OBJECTIVES: To investigate the ability of new generation snapshot freeze (NGSSF) algorithm in improving diagnostic image quality of both aortic valve and coronary arteries for transcatheter aortic valve implantation (TAVI) candidates in TAVI planning CT. METHODS: Sixty-four TAVI candidates underwent TAVI planning CT were enrolled. Scans from coronary CT angiography were reconstructed at 20%, 30%, 40%, and 75% R-R cardiac phases with NGSSF and standard (STD) algorithm. In each phase, following parameters were compared: aortic valve measurements and their reproducibility; image quality of aortic valve and coronary arteries. The diagnostic accuracies of TAVI planning CT for coronary artery stenosis in 30% R-R phase with NGSSF and STD algorithms were calculated in 47out of 64 patients with invasive coronary angiography as reference standard. RESULTS: For subjective image quality evaluation, the excellent rate for aortic valve improved from 25.0% to 93.8% and the interpretable rate for coronary arteries increased from 20.3% to 95.3% in the 30% phase images with NGSSF compared with images with STD. For the detection of > 50% coronary artery stenosis, the 30% phase images with NGSSF provided a sensitivity of 90%, specificity of 81.48%, negative predictive value of 91.7%, and positive predictive value of 78.3% on a per-patient basis; While images with STD, had a corresponding results of 95.0%, 33.33%, 90.0%, and 51.4%, respectively. CONCLUSIONS: NGSSF significantly improves image quality for both aortic valve and coronary arteries compared with STD for TAVI patients of all heart rates. NGSSF enables the accurate measurement for aortic valve and satisfactory diagnostic performance for coronary arteries stenosis in the same systolic phase for TAVI planning.


Assuntos
Estenose da Valva Aórtica , Estenose Coronária , Humanos , Algoritmos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Angiografia Coronária/métodos , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/cirurgia , Vasos Coronários , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos , Substituição da Valva Aórtica Transcateter/métodos
10.
Front Cardiovasc Med ; 10: 1160142, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547252

RESUMO

Objective: This article aims to investigate the incidence rate of retrograde type A aortic dissection (RTAD) and the risk factors of RTAD in relation to thoracic endovascular aortic repair (TEVAR). Methods: Patients with thoracic aortic disease who underwent TEVAR at Henan Provincial People's Hospital from January 2004 to December 2019 were enrolled in the present research. The risk factors associated with RTAD following TEVAR using univariate and multiple logistic regression analyses. Results: During the study period, A total of 1,688 TEVAR patients were included in this study, and of these, 1,592 cases were included in the type B aortic dissection (TBAD) group, and 96 cases were included in the non-TBAD group. There were 1,230 cases of aortic dissection and 362 cases of aortic intramural hematoma and/or penetrating ulcer in the TBAD group. The non-TBAD group included 68 cases of thoracic aortic aneurysm, 21 cases of thoracic aortic pseudoaneurysm, and seven cases of congenital aortic coarctation. The overall incidence rate of RTAD was 1.1% (18/1,688) in patients, all of which occurred in the TBAD group. The cohort comprised 18 RTAD patients with an average age of 56.78, consisting of 13 males and 5 females. Among them, 13 individuals exhibited hypertension. Ten instances happened within the TEVAR perioperative period, including two cases during the surgery, six cases occurred within three months, two cases occurred after one year, and the longest interval was 72 months following TEVAR. TEVAR was successfully implemented in 17 patients, while the operation technique was temporarily altered in one case. The new entry position for RTAD was identified as the proximal region of the stent graft (SG) in 13 patients, while in five cases, the entry site was more than 2 cm away from the proximal region of the SG. 17 cases were at the greater curvature of the aorta, and one case was at the lesser curvature. Multivariate logistic regression analysis revealed that the SG oversizing ratio is a relevant risk factor for RTAD. However, ascending aortic diameter, aortic arch type, SG type, and anchored region were not directly related to the occurrence of RTAD. Conclusion: RTAD is a rare yet catastrophic complication. It could occur both during the procedure, early and late postoperative periods. Maintaining an appropriate SG oversizing ratio is crucial to minimize the risk of RTAD.

11.
J Appl Clin Med Phys ; 24(9): e14104, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37485892

RESUMO

PURPOSE: To investigate the performance of a deep learning-based motion correction algorithm (MCA) at various cardiac phases of coronary computed tomography angiography (CCTA), and determine the extent to which it may allow for reliable morphological and functional evaluation. MATERIALS AND METHODS: The acquired image data of 53 CCTA cases, where the patient heart rate (HR) was ≥75 bpm, were reconstructed at 0, ±2, ±4, ±6, and ±8% deviations from each optimal systolic phase, with and without the MCA, yielding a total of 954 images (53 cases × 9 phases × 2 reconstructions). The overall image quality and diagnostic confidence were graded by two radiologists using a 5-point scale, with scores ≥3 being deemed clinically interpretable. Signal-to-noise ratio, contrast-to-noise ratio, vessel sharpness, and circularity were measured. The CCTA-derived fractional flow reserve (CT-FFR) was calculated in 38 vessels on 24 patients to identify functionally significant stenosis, using the invasive fractional flow reserve (FFR) as reference. All metrics were compared between two reconstructions at various phases. RESULTS: Inferior image quality was observed as the phase deviation was enlarged. However, MCA significantly improved the image quality at nonoptimal phases and the optimal phase. Coronary artery evaluation was feasible within 4% phase deviation using MCA, with interpretable overall image quality and high diagnostic confidence. With MCA, the performance of identifying functionally significant stenosis via CT-FFR was increased for images at various phase deviations. However, obvious decrease in accuracy, as compared to the image at the optimal phase, was found on those with deviations >4%. CONCLUSION: The deep learning-based MCA allows up to 4% phase deviation in acquiring CCTA for reliable morphological and functional evaluation on patients with high HRs.


Assuntos
Doença da Artéria Coronariana , Aprendizado Profundo , Reserva Fracionada de Fluxo Miocárdico , Humanos , Angiografia por Tomografia Computadorizada , Constrição Patológica , Estudos Retrospectivos , Angiografia Coronária/métodos , Tomografia Computadorizada por Raios X , Algoritmos
12.
Food Chem Toxicol ; 177: 113855, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37230459

RESUMO

Foxtail millet is a traditional excellent crop with high nutritional value in the world, belong to cereals. The bran of foxtail millet is rich in polyphenol that has antioxidant, anti-inflammatory, and anti-tumorigenic effects. Previously, we extracted bound polyphenols from the inner shell of foxtail millet bran (BPIS). Here, we report that BPIS specifically induced breast cancer cell death and elevated the autophagy level simultaneously. The addition of an autophagy inhibitor blocked BPIS-induced breast cancer cell death, indicating that excessive autophagy induced cell death. Furthermore, oil red O and BODIPY staining also confirmed that lipids, which are important inducers of autophagy, accumulated in breast cancer cells treated with BPIS. Lipidomics research revealed that glycerophospholipids were the main accumulated lipids induced by BPIS. Further study showed that elevated PCYT1A expression was responsible for glycerophospholipid accumulation, and BPIS contained ferulic acid and p-coumaric acid, which induced PCYT1A expression and breast cancer cell death. Collectively, our results revealed that BPIS resulted in autophagic death by enhancing lipid accumulation in breast cancer cells, and BPIS contains ferulic acid and p-coumaric acid, which provided new insights into developing nutraceuticals and drugs for breast cancer patients.


Assuntos
Neoplasias da Mama , Setaria (Planta) , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Setaria (Planta)/metabolismo , Polifenóis/farmacologia , Polifenóis/metabolismo , Lipídeos
13.
Eur J Radiol ; 161: 110736, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36804314

RESUMO

PURPOSE: To investigate the use of an 80-kVp tube voltage combined with a deep learning image reconstruction (DLIR) algorithm in coronary CT angiography (CCTA) for overweight patients to reduce radiation and contrast doses in comparison with the 120-kVp protocol and adaptive statistical iterative reconstruction (ASIR-V). METHODS: One hundred consecutive CCTA patients were prospectively enrolled and randomly divided into a low-dose group (n = 50) with 80-kVp, smart mA for noise index (NI) of 36 HU, contrast dose rate of 18 mgI/kg/s and DLIR and 60 % ASIR-V and a standard-dose group (n = 50) with 120-kVp, smart mA for NI of 25 HU, contrast dose rate of 32 mgI/kg/s and 60 % ASIR-V. The radiation and contrast dose, subjective image quality score, attenuation values, noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were compared. RESULTS: The low-dose group achieved a significant reduction in the effective radiation dose (1.01 ± 0.45 mSv vs 1.85 ± 0.40 mSv, P < 0.001) and contrast dose (33.69 ± 3.87 mL vs 59.11 ± 5.60 mL, P < 0.001) compared to the standard-dose group. The low-dose group with DLIR presented similar enhancement but lower noise, higher SNR and CNR and higher subjective quality scores than the standard-dose group. Moreover, the same patient comparison in the low-dose group between different reconstructions showed that DLIR images had slightly and consistently higher CT values in small vessels, indicating better defined vessels, much lower image noise, higher SNR and CNR and higher subjective quality scores than ASIR-V images (all P < 0.001). CONCLUSIONS: The application of 80-kVp and DLIR allows for significant radiation and dose reduction while further improving image quality in CCTA for overweight patients.


Assuntos
Angiografia por Tomografia Computadorizada , Aprendizado Profundo , Humanos , Angiografia por Tomografia Computadorizada/métodos , Sobrepeso/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Angiografia Coronária/métodos , Processamento de Imagem Assistida por Computador , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Algoritmos
14.
Sensors (Basel) ; 23(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36772743

RESUMO

The time maintenance accuracy of the navigation constellation determines the user positioning and timing performance. Especially in autonomous operation scenarios, the performance of navigation constellation maintenance time directly affects the duration of constellation autonomous navigation. Among them, the frequency stability of the atomic clock onboard the navigation satellite is a key factor. In order to further improve the stability of the navigation constellation time-frequency system, combined with the development of high-precision inter-satellite link measurement technology, the idea of constructing constellation-level synthetic atomic time has gradually become the development trend of major GNSS systems. This paper gives a navigation constellation time scale generation framework, and designs an improved Kalman plus weights (KPW) time scale algorithm and time-frequency steer algorithm that integrates genetic algorithms. Finally, a 30-day autonomous timekeeping simulation was carried out using the GPS precision clock data provided by CODE, when the sampling interval is 300 s, the Allan deviation of the output time scale is 5.73 × 10-14, a 71% improvement compared with the traditional KPW time scale algorithm; when the sampling interval is 1 day, the Allan deviation is 9.17 × 10-15; when the sampling interval is 1 × 106 s, the Allan deviation is 8.87 × 10-16, a 94% improvement compared with the traditional KPW time scale algorithm. The constellation-level high-precision time scale generation technology proposed in this paper can significantly improve the stability performance of navigation constellation autonomous timekeeping.

15.
Front Cardiovasc Med ; 9: 870378, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072859

RESUMO

Objectives: The aim of this study was to review our management experience of ruptured abdominal aortic aneurysms (RAAAs) using an endovascular aneurysm repair (EVAR)-only strategy, and discuss the feasibility of this strategy. Materials and methods: A retrospective analysis of clinical data was performed in patients with RAAAs from January 2009 to October 2020. Our strategy toward operative treatment for RAAAs evolved from an EVAR-selected (from January 2009 to April 2014) to an EVAR-only (from May 2014 to October 2020) strategy. Baseline characteristics, thirty-day mortality, perioperative complications, and long-term outcomes of patients were compared between the two periods. Results: A total of 93 patients undergoing emergent RAAA repair were eventually included. The overall operation rate in RAAAs at our centre was 70.5% (93/132). In the EVAR-only period, all 53 patients underwent ruptured endovascular aneurysm repair (rEVAR). However, only 47.5% (19/40) of patients in the EVAR-selected period underwent rEVAR, and the remaining 21 patients underwent emergent open surgery. Thirty-day mortality in the EVAR-only group was 22.6% (12/53) compared with 25.0% (10/40) for the EVAR-selected group (P = 0.79). Systolic blood pressure ≤70 mmHg [adjusted odds ratio (OR) 4.99, 95% confidence interval (CI), 1.13-22.08, P = 0.03] and abdominal compartment syndrome (adjusted OR 3.72, 95% CI, 1.12-12.32, P = 0.03) were identified as independent risk factors responsible for 30-day mortality. After 5 years, 47.5% (95% CI, 32.0-63.0%) of patients in the EVAR-selected group were still alive versus 49.1% (95% CI, 32.3-65.9%) of patients in the EVAR-only group (P = 0.29). Conclusion: The EVAR-only strategy has allowed rEVAR to be used in nearly all the RAAAs with similar mortality comparing with the EVAR-selected strategy. Due to the avoidance of operative modality selection, the EVAR-only strategy was associated with a more simplified algorithm, less influence on haemodynamics, and a shorter operation and recovery time.

16.
Sheng Li Xue Bao ; 74(2): 188-200, 2022 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-35503066

RESUMO

Atrial Ca2+ handling abnormalities, mainly involving the dysfunction of ryanodine receptor (RyR) and sarcoplasmic reticulum Ca2+-ATPase (SERCA), play a role in the pathogenesis of atrial fibrillation (AF). Previously, we found that the expression and function of transient receptor potential vanilloid subtype 4 (TRPV4) are upregulated in a sterile pericarditis (SP) rat model of AF, and oral administration of TRPV4 inhibitor GSK2193874 alleviates AF in this animal model. The aim of this study was to investigate whether oral administration of GSK2193874 could alleviate atrial Ca2+ handling abnormalities in SP rats. A SP rat model of AF was established by daubing sterile talcum powder on both atria of Sprague-Dawley (SD) rats after a pericardiotomy, to simulate the pathogenesis of postoperative atrial fibrillation (POAF). On the 3rd postoperative day, Ca2+ signals of atria were collected in isolated perfused hearts by optical mapping. Ca2+ transient duration (CaD), alternan, and the recovery properties of Ca2+ transient (CaT) were quantified and analyzed. GSK2193874 treatment reversed the abnormal prolongation of time to peak (determined mainly by RyR activity) and CaD (determined mainly by SERCA activity), as well as the regional heterogeneity of CaD in SP rats. Furthermore, GSK2193874 treatment relieved alternan in SP rats, and reduced its incidence of discordant alternan (DIS-ALT). More importantly, GSK2193874 treatment prevented the reduction of the S2/S1 CaT ratio (determined mainly by RyR refractoriness) in SP rats, and decreased its regional heterogeneity. Taken together, oral administration of TRPV4 inhibitor alleviates Ca2+ handling abnormalities in SP rats primarily by blocking the TRPV4-Ca2+-RyR pathway, and thus exerts therapeutic effect on POAF.


Assuntos
Fibrilação Atrial , Pericardite , Administração Oral , Animais , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/etiologia , Cálcio/metabolismo , Miócitos Cardíacos/metabolismo , Pericardite/complicações , Pericardite/metabolismo , Pericardite/patologia , Ratos , Ratos Sprague-Dawley , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/farmacologia , Retículo Sarcoplasmático/metabolismo , Retículo Sarcoplasmático/patologia , Canais de Cátion TRPV
18.
Eur J Radiol ; 149: 110221, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35196615

RESUMO

PURPOSE: To investigate the image quality and feasibility of a novel artificial intelligence iterative reconstruction (AIIR) algorithm for aortic computer tomography angiography (CTA) with a low radiation dose and contrast material (CM) dosage protocol in comparison with hybrid iterative reconstruction (HIR) algorithm for standard-of-care aortic CTA. METHODS: Fifty consecutive patients (mean age 58 ± 14 years, mean BMI 24.5 ± 4.7 kg/m2) with aortic diseases were prospectively enrolled. All patients underwent at least twice follow-up aortic CTA examinations. Standard dose CT (SDCT) was applied in the initial follow-up examination (100 kVp, auto mAs, contrast dose 0.8 mgL/kg), images were reconstructed with HIR (SDCT-HIR). In the second follow-up examination, patients underwent scanning with low dose CT (LDCT) (70 kVp, auto mAs, contrast dose 0.5 mgL/kg), images were reconstructed with HIR (LDCT-HIR) as well as AIIR (LDCT-AIIR). Attenuation values, noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured for objective analysis. Subjective image quality was rated by two blinded radiologists using a 5-point scale. The effective radiation dose and CM dosage were also recorded. RESULTS: The effective radiation dose (1.58 ± 0.17 mSv vs. 9.96 ± 1.05 mSv, P < 0.001) and CM dosage (34.38 ± 5.43 ml vs. 54.64 ± 8.63 ml, P < 0.001) achieved a remarkable reduction of 84.14% and 37.08% in the LDCT compared to the SDCT. The attenuation was similar among the three reconstructed images (P > 0.05). Compared to LDCT-HIR images, LDCT-AIIR showed a lower noise and higher SNR and CNR. For qualitative analysis, there were no significant differences between the LDCT-AIIR and the SDCT-HIR images among four metrics (P > 0.05). CONCLUSIONS: Compared to standard-of-care aortic CTA with HIR, the application of the AIIR algorithm allows for radiation dose and CM dosage reduction while preserving image quality on low dose aortic CTA.


Assuntos
Inteligência Artificial , Interpretação de Imagem Radiográfica Assistida por Computador , Adulto , Idoso , Algoritmos , Computadores , Meios de Contraste , Estudos de Viabilidade , Humanos , Pessoa de Meia-Idade , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos
19.
Eur Radiol ; 32(5): 2912-2920, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35059803

RESUMO

OBJECTIVES: To explore the use of 70-kVp tube voltage combined with high-strength deep learning image reconstruction (DLIR-H) in reducing radiation and contrast doses in coronary CT angiography (CCTA) in patients with body mass index (BMI) < 26 kg/m2, in comparison with the conventional scan protocol using 120 kVp and adaptive statistical iterative reconstruction (ASIR-V). METHODS: A total of 100 patients referred to CCTA were prospectively enrolled and randomly divided into two groups: low-dose group (n = 50) with 70 kVp, Smart mA for noise index (NI) of 36HU, contrast dose rate of 16mgI/kg/s, and DLIR-H, and conventional group (n = 50) with 120 kV, Smart mA for NI of 25HU, contrast dose rate of 32mgI/kg/s, and 60%ASIR-V. Radiation and contrast dose, subjective image quality score, and objective image quality measurement (image noise, contrast-noise-ratio (CNR), and signal-noise-ratio (SNR) for vessel) were compared between the two groups. RESULTS: Low-dose group used significantly reduced contrast dose (23.82 ± 3.69 mL, 50.6% reduction) and radiation dose (0.75 ± 0.14 mSv, 54.5% reduction) compared to the conventional group (48.23 ± 6.38 mL and 1.65 ± 0.66 mSv, respectively) (all p < 0.001). Both groups had similar enhancement in vessels. However, the low-dose group had lower background noise (23.57 ± 4.74 HU vs. 35.04 ± 8.41 HU), higher CNR in RCA (48.63 ± 10.76 vs. 29.32 ± 5.52), LAD (47.33 ± 10.20 vs. 29.27 ± 5.12), and LCX (46.74 ± 9.76 vs. 28.58 ± 5.12) (all p < 0.001) compared to the conventional group. CONCLUSIONS: The use of 70-kVp tube voltage combined with DLIR-H for CCTA in normal size patients significantly reduces radiation dose and contrast dose while further improving image quality compared with the conventional 120-kVp tube voltage with 60%ASIR-V. KEY POINTS: • The combination of 70-kVp tube voltage and high-strength deep learning image reconstruction (DLIR-H) algorithm protocol reduces approximately 50% of radiation and contrast doses in coronary computed tomography angiography (CCTA) compared with the conventional scan protocol. • CCTA of normal size (BMI < 26 kg/m2) patients acquired at sub-mSv radiation dose and 24 mL contrast dose through the combination of 70-kVp tube voltage and DLIR-H algorithm achieves excellent diagnostic image quality with a good inter-rater agreement. • DLIR-H algorithm shows a higher capacity of significantly reducing image noise than adaptive statistical iterative reconstruction algorithm in CCTA examination.


Assuntos
Angiografia por Tomografia Computadorizada , Aprendizado Profundo , Algoritmos , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste , Angiografia Coronária/métodos , Humanos , Processamento de Imagem Assistida por Computador , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos
20.
Eur Radiol ; 32(2): 1034-1043, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34338842

RESUMO

OBJECTIVE: To evaluate the image quality and diagnostic performance for obstructive coronary artery disease of transcatheter aortic valve implantation (TAVI) patients with atrial fibrillation (AF) during TAVI planning CT using a whole-heart coverage CT scanner. METHODS: Eighty-eight consecutive TAVI candidates with AF (50 men, 74 ± 6 years) who underwent both TAVI planning CT and invasive coronary catheter angiography (ICA) were retrospectively analyzed. With ICA results as the reference standard, the accuracy of TAVI planning CT for lesion detection on a per-vessel and per-patient level was calculated. Meanwhile, image quality, contrast volume, and effective dose (ED) were evaluated. A 5-point visual scale (1-5) was used to assess the subjective image quality. The CT value and signal-to-noise ratio were measured for the left main coronary artery (LM), left anterior descending (LAD), left circumflex (LCX), and right coronary arteries (RCA). RESULTS: The ED for CCTA was 3.25 ± 1.39 mSv and contrast volume was 58.14 ± 12.34 mL. A total of 1371 (1371/1408 = 97.4%) segments with diameter > 1.5 mm were analyzed. For the subjective evaluation, the mean score was 3.99 ± 0.96 for overall image quality. The mean CT values in LM, RCA, LCX, and LAD were all above 400 HU. For the detection of > 50% stenosis, TAVI planning CT provided on the per-vessel and per-patient basis 97.06% and 100% in sensitivity, 96.23% and 89.06% in specificity, 99.7% and 100% in negative predictive value, and 73.3% and 77.4% in positive predictive value, respectively. CONCLUSION: TAVI planning CT with whole-heart coverage demonstrates good CCTA image quality and a high sensitivity and NPV in excluding obstructive CAD in TAVI candidates with AF. KEY POINTS: • Transcatheter aortic valve implantation planning (TAVI) CT with whole-heart coverage enables good image quality of CCTA in TAVI candidates with atrial fibrillation. • Obstructive coronary artery disease may be excluded with high accuracy in transcatheter aortic valve implantation (TAVI) candidates with atrial fibrillation with the usage of whole-heart coverage TAVI planning CT.


Assuntos
Estenose da Valva Aórtica , Fibrilação Atrial , Substituição da Valva Aórtica Transcateter , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Humanos , Masculino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
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