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1.
Compr Rev Food Sci Food Saf ; 23(3): e13343, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38629458

RESUMO

Innovations in food packaging systems could meet the evolving needs of the market; emerging concepts of non-migrating technologies reduce the negative migration of preservatives from packaging materials, extend shelf life, and improve food quality and safety. Non-migratory packaging activates the surface of inert materials through pretreatment to generate different active groups. The preservative is covalently grafted with the resin of the pretreated packaging substrate through the graft polymerization of the monomer and the coupling reaction of the polymer chain. The covalent link not only provides the required surface properties of the material for a long time but also retains the inherent properties of the polymer. This technique is applied to the processing for durable, stable, and easily controllable packaging widely. This article reviews the principles of various techniques for packaging materials, surface graft modification, and performance characterization of materials after grafting modification. Potential applications in the food industry and future research trends are also discussed.


Assuntos
Embalagem de Alimentos , Armazenamento de Alimentos , Embalagem de Alimentos/métodos , Polímeros/química , Qualidade dos Alimentos
2.
ACS Appl Mater Interfaces ; 16(15): 19318-19329, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38577894

RESUMO

Studies indicated that two-dimensional (2D) metal halide perovskites (MHPs) embodied with three-dimensional (3D) MHPs were a facile way to realize efficient and stable perovskite solar cells (PSCs) and perovskite photodetectors (PPDs). Here, high-performance PSCs and PPDs, which are based on 2D/3D MHPs bilayer thin films, where the 2D MHPs are created by binary conjugated organic cations, are reported. Systemically studies reveal that the above novel 2D/3D MHPs bilayer thin films possess an enlarged crystal size, balanced charge transport, reduced charge carrier recombination, smaller charge-transfer resistance, and accelerated charge-extraction process compared to the 2D/3D MHPs bilayer thin films, where the 2D MHPs are created by a single conjugated organic cation. As a result, the PSCs based on the above novel 2D/3D MHPs bilayer thin film exhibit a power conversion efficiency of 22.76%. Moreover, unencapsulated PSCs possess dramatically enhanced stability compared with those based on the 2D/3D MHPs bilayer thin films, where the 2D MHPs are created by a single conjugated organic cation. In addition, the PPDs based on the above novel 2D/3D MHPs bilayer thin film exhibit a projected detectivity of 1016 cm Hz1/2/W and a linear dynamic range of 108 dB at room temperature. Our studies indicate that the development of binary conjugated organic cation-based 2D MHPs incorporated with 3D MHPs is a simple method to realize high-performance PSCs and PPDs.

3.
Ann Vasc Surg ; 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38593922

RESUMO

OBJECTIVES: Premature peripheral artery disease (PAD), defined by lower extremity revascularization (LER) at age ≤ 50 years, is associated with poor major adverse limb events. The early onset of disease is thought to be influenced by genetic factors that regulate homeostasis of the vascular wall and coagulation. The aim of this study is to investigate the effect of anticoagulation as an adjunct to antiplatelet therapy on the outcomes of LER in patients with premature PAD. METHODS: There were 8,804 patients with premature PAD on pre- and post-operative antiplatelet therapy only and 1,236 patients on pre- and post-operative anticoagulation plus antiplatelet therapy in the Vascular Quality Initiative (VQI) peripheral vascular intervention, infra-, and suprainguinal files. Propensity score matching (2:1) was performed between patients with premature PAD who were on antiplatelet therapy and those on anticoagulation plus antiplatelet therapy. Perioperative and one-year outcomes were analyzed including reintervention, major amputation, and mortality. RESULTS: Patients on anticoagulation were more likely to have coronary artery disease (48.7% vs 41.2%, P<.001), congestive heart failure (20.2% vs 13.1%, P<.001), and have undergone prior LER (73.9% vs 49.2%, P<.001) compared to patients on antiplatelet therapy only. They were also less likely to be independently ambulatory (74.2% vs 81.8%, P<.001) and be on a statin medication (66.8% vs 74.3%, P<.001) compared to patients on antiplatelet therapy only. Patients on anticoagulation were also less likely to be treated for claudication (38.1% vs 48.6%, P<.001), and less likely to be treated with an endovascular procedure (64.8% vs 73.8%, P<.001). After matching for baseline characteristics, there were 1,256 patients on antiplatelet therapy only and 628 patients on anticoagulation. Patients on anticoagulation were more likely to require a return to the operating room (3.7% vs 1.6%, P<.001) and had higher perioperatively mortality (1.1% vs 0.3%, P=.032), but major amputation was not significantly different (1.8% vs 1.6%, P=.798) compared to patients on antiplatelet therapy alone. At one-year, amputation-free survival was higher in patients on antiplatelets only compared to patients on anticoagulation and antiplatelet medications (87.5% vs 80.9%, log-rank P=.001). CONCLUSION: Anticoagulation in addition to antiplatelet therapy in patients with premature PAD undergoing lower extremity revascularization is associated with increased reintervention and mortality at one year.

4.
Angew Chem Int Ed Engl ; : e202401635, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597773

RESUMO

The introduction of an abiological catalytic group into the binding pocket of a protein host allows for the expansion of enzyme chemistries. Here, we report the generation of an artificial enzyme by genetic encoding of a non-canonical amino acid that contains a secondary amine side chain. The non-canonical amino acid and the binding pocket function synergistically to catalyze the asymmetric nitrocyclopropanation of α,ß-unsaturated aldehydes by the iminium activation mechanism. The designer enzyme was evolved to an optimal variant that catalyzes the reaction in high yield with high diastereo- and enantioselectivity. This work demonstrates the application of genetic code expansion in enzyme design and expands the scope of enzyme-catalyzed abiological reactions.

5.
J Toxicol Environ Health A ; 87(10): 448-456, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38557302

RESUMO

Cerebral ischemia-reperfusion injury (CIRI) occurs frequently clinically as a complication following cardiovascular resuscitation resulting in neuronal damage specifically to the hippocampal CA1 region with consequent cognitive impairment. Apoptosis and oxidative stress were proposed as major risk factors associated with CIRI development. Previously, glycosides obtained from Cistanche deserticola (CGs) were shown to play a key role in counteracting CIRI; however, the underlying mechanisms remain to be determined. This study aimed to investigate the neuroprotective effect of CGs on subsequent CIRI in rats. The model of CIRI was established for 2 hr and reperfusion for 24 hr by middle cerebral artery occlusion (MCAO) model. The MCAO rats were used to measure the antioxidant and anti-apoptotic effects of CGs on CIRI. Neurological function was evaluated by the Longa neurological function score test. 2,3,5-Triphenyltetrazolium chloride (TTC) staining was used to detect the area of cerebral infarction. Nissl staining was employed to observe neuronal morphology. TUNEL staining was used to detect neuronal apoptosis, while Western blot determined protein expression levels of factors for apoptosis-related and PI3K/AKT/Nrf2 signaling pathway. Data demonstrated that CGs treatment improved behavioral performance, brain injury, and enhanced antioxidant and anti-apoptosis in CIRI rats. In addition, CGs induced activation of PI3K/AKT/Nrf2 signaling pathway accompanied by inhibition of the expression of apoptosis-related factors. Evidence indicates that CGs amelioration of CIRI involves activation of the PI3K/AKT/Nrf2 signaling pathway associated with increased cellular viability suggesting these glycosides may be considered as an alternative compound for CIRI treatment.


Assuntos
Isquemia Encefálica , Cistanche , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Animais , Ratos Sprague-Dawley , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antioxidantes/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fosfatidilinositol 3-Quinases/farmacologia , Glicosídeos/farmacologia , Glicosídeos/uso terapêutico , Fator 2 Relacionado a NF-E2/farmacologia , Apoptose , Isquemia Encefálica/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Fármacos Neuroprotetores/farmacologia
6.
Nano Lett ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619219

RESUMO

Current density imaging is helpful for discovering interesting electronic phenomena and understanding carrier dynamics, and by combining pressure distributions, several pressure-induced novel physics may be comprehended. In this work, noninvasive, high-resolution two-dimensional images of the current density and pressure gradient for graphene ribbon and hBN-graphene-hBN devices are explored using nitrogen-vacancy (NV) centers in diamond under high pressure. The two-dimensional vector current density is reconstructed by the vector magnetic field mapped by the near-surface NV center layer in the diamond. The current density images accurately and clearly reproduce the complicated structure and current flow of graphene under high pressure. Additionally, the spatial distribution of the pressure is simultaneously mapped, rationalizing the nonuniformity of the current density under high pressure. The current method opens a significant new avenue to investigate electronic transport and conductance variations in two-dimensional materials and electrical devices under high pressure as well as for nondestructive evaluation of semiconductor circuits.

7.
Int J Biol Macromol ; 266(Pt 2): 131440, 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38593898

RESUMO

Polygonatum kingianum Coll & Hemsl is an important Chinese medicine used for enhancing physical function and anti-fatigue, and polysaccharides (PKPs) are considered as the main bioactive components. However, the mechanisms through which PKPs exert their anti-fatigue effects are not fully understood. This study aimed more comprehensively to explore the anti-fatigue mechanisms of PKPs, focusing on metabolism, protein expression, and gut flora, by using exhaustive swimming experiments in mice. Results showed a significant increase in the exhaustive swimming time of the mice treated with PKPs, especially in the high-dose group (200 mg/kg/day). Further studies showed that PKPs remarkably improves several fatigue-related physiological indices. Additionally, 16S rRNA sequence analysis showed that PKPs increased antioxidant bacteria (e.g., g_norank_f_Muribaculaceae) and the production of short-chain fatty acids (SCFAs), while reducing the abundance of harmful bacteria (e.g., g_Escherichia-Shigella and g_Helicobacter). PKPs also mitigated oxidative stress through activating the NRF2/HO-1 signaling pathway, and promoted energy metabolism by upregulating the expression of AMPK/PGC-1α/TFAM signaling pathway proteins. This research may offer theoretical support for incorporating PKPs as a novel dietary supplement in functional foods targeting anti-fatigue properties.

8.
J Toxicol Environ Health A ; 87(11): 471-479, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38590254

RESUMO

Cannabidiol (CBD), a natural component extracted from Cannabis sativa L. exerts neuroprotective, antioxidant, and anti-inflammatory effects in Alzheimer's disease (AD), a disease characterized by impaired cognition and accumulation of amyloid-B peptides (Aß). Interactions between the gut and central nervous system (microbiota-gut-brain axis) play a critical role in the pathogenesis of neurodegenerative disorder AD. At present investigations into the mechanisms underlying the neuroprotective action of CBD in AD are not conclusive. The aim of this study was thus to examine the influence of CBD on cognition and involvement of the microbiota-gut-brain axis using a senescence-accelerated mouse prone 8 (SAMP8) model. Data demonstrated that administration of CBD to SAMP8 mice improved cognitive function as evidenced from the Morris water maze test and increased hippocampal activated microglia shift from M1 to M2. In addition, CBD elevated levels of Bacteriodetes associated with a fall in Firmicutes providing morphologically a protective intestinal barrier which subsequently reduced leakage of intestinal toxic metabolites. Further, CBD was found to reduce the levels of hippocampal and colon epithelial cells lipopolysaccharide (LPS), known to be increased in AD leading to impaired gastrointestinal motility, thereby promoting neuroinflammation and subsequent neuronal death. Our findings demonstrated that CBD may be considered a beneficial therapeutic drug to counteract AD-mediated cognitive impairment and restore gut microbial functions associated with the observed neuroprotective mechanisms.


Assuntos
Doença de Alzheimer , Canabidiol , Disfunção Cognitiva , Camundongos , Animais , Doença de Alzheimer/tratamento farmacológico , Canabidiol/farmacologia , Canabidiol/uso terapêutico , Eixo Encéfalo-Intestino , Cognição , Disfunção Cognitiva/tratamento farmacológico , Modelos Animais de Doenças
9.
Arch Pathol Lab Med ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38569599

RESUMO

CONTEXT.­: High-grade transformation, previously known as dedifferentiation, in salivary gland carcinoma and carcinosarcoma ex pleomorphic adenoma is a rare phenomenon. It is, however, clinically relevant and affects treatment and prognosis. OBJECTIVE.­: To review the existing literature, describe the histologic and immunophenotypic features, and highlight the diagnostic criteria of high-grade transformation in various salivary gland carcinomas and carcinosarcoma; to review its effect on clinical presentation and prognosis; and to review relevant molecular characteristics and recent concepts and advances. DATA SOURCES.­: Literature search in PubMed using key words such as "high-grade transformation," "dedifferentiation," and "carcinosarcoma" in salivary gland. Relevant articles were reviewed, and additional articles were curated from the references of these articles. CONCLUSIONS.­: High-grade transformation occurs rarely but has a significant impact on prognosis and management. By microscopy, the high-grade area is usually a distinct nodule and shows solid and nested architecture, cellular atypia, high mitotic count, and necrosis. The molecular features are not well established. Carcinosarcoma almost always arises in a pleomorphic adenoma and likely follows an adenoma-carcinoma-sarcoma pathway.

10.
Stroke Vasc Neurol ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38569895

RESUMO

BACKGROUND AND OBJECTIVE: The injury of the cholinergic white matter pathway underlies cognition decline in patients with silent cerebrovascular disease (SCD) with white matter hyperintensities (WMH) of vascular origin. However, the evaluation of the cholinergic white matter pathway is complex with poor consistency. We established an intelligent algorithm to evaluate WMH in the cholinergic pathway. METHODS: Patients with SCD with WMH of vascular origin were enrolled. The Cholinergic Pathways Hyperintensities Scale (CHIPS) was used to measure cholinergic white matter pathway impairment. The intelligent algorithm used a deep learning model based on convolutional neural networks to achieve WMH segmentation and CHIPS scoring. The diagnostic value of the intelligent algorithm for moderate-to-severe cholinergic pathway injury was calculated. The correlation between the WMH in the cholinergic pathway and cognitive function was analysed. RESULTS: A number of 464 patients with SCD were enrolled in internal training and test set. The algorithm was validated using data from an external cohort comprising 100 patients with SCD. The sensitivity, specificity and area under the curve of the intelligent algorithm to assess moderate and severe cholinergic white matter pathway injury were 91.7%, 87.3%, 0.903 (95% CI 0.861 to 0.952) and 86.5%, 81.3%, 0.868 (95% CI 0.819 to 0.921) for the internal test set and external validation set. for the. The general cognitive function, execution function and attention showed significant differences among the three groups of different CHIPS score (all p<0.05). DISCUSSION: We have established the first intelligent algorithm to evaluate the cholinergic white matter pathway with good accuracy compared with the gold standard. It helps more easily assess the cognitive function in patients with SCD.

11.
Cereb Cortex ; 34(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38566514

RESUMO

Cooperation and competition are the most common forms of social interaction in various social relationships. Intergroup relationships have been posited to influence individuals' interpersonal interactions significantly. Using electroencephalography hyperscanning, this study aimed to establish whether intergroup relationships influence interpersonal cooperation and competition and the underlying neural mechanisms. According to the results, the in-group Coop-index is better than the out-group, whereas the out-group Comp-index is stronger than the in-group. The in-group functional connectivity between the frontal-central region and the right temporoparietal junction in the ß band was stronger in competition than cooperation. The out-group functional connectivity between the frontal-central region and the left temporoparietal junction in the α band was stronger in cooperation than competition. In both cooperation and competition, the in-group exhibited higher interbrain synchronization between the prefrontal cortex and parietal region in the θ band, as well as between the frontal-central region and frontal-central region in the α band, compared to the out-group. The intrabrain phase-locking value in both the α and ß bands can effectively predict performance in competition tasks. Interbrain phase-locking value in both the α and θ bands can be effectively predicted in a performance cooperation task. This study offers neuroscientific evidence for in-group favoritism and out-group bias at an interpersonal level.


Assuntos
Comportamento Cooperativo , Eletroencefalografia , Humanos , Eletroencefalografia/métodos , Córtex Pré-Frontal , Relações Interpessoais , Lobo Parietal , Encéfalo , Mapeamento Encefálico
12.
ACS Sens ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565844

RESUMO

As a carcinogenic and highly neurotoxic hazardous gas, benzene vapor is particularly difficult to be distinguished in BTEX (benzene, toluene, ethylbenzene, xylene) atmosphere and be detected in low concentrations due to its chemical inertness. Herein, we develop a depth-related pore structure in Cu-TCPP-Cu to thermodynamically and kinetically enhance the adsorption of benzene vapor and realize the detection of ultralow-temperature benzene gas. We find that the in-plane π electronic nature and proper pore sizes in Cu-TCPP-Cu can selectively induce the adsorption and diffusion of BTEX. Interestingly, the theoretical calculations (including density functional theory (DFT) and grand canonical Monte Carlo (GCMC) simulations) exhibit that benzene molecules are preferred to adsorb and array as a consecutive arrangement mode in the Cu-TCPP-Cu pore, while the TEX (toluene, ethylbenzene, xylene) dominate the jumping arrangement model. The differences in distribution behaviors can allow adsorption and diffusion of more benzene molecules within limited room. Furthermore, the optimal pore-depth range (60-65 nm) of Cu-TCPP-Cu allows more exposure of active sites and hinders the gas-blocking process. The optimized sensor exhibits ultrahigh sensitivity to benzene vapor (155 Hz/µg@1 ppm), fast response time (less than 10 s), extremely low limit of detection (65 ppb), and excellent selectivity (83%). Our research thus provides a fundamental understanding to design and optimize two-dimensional metal-organic framework (MOF)-based gas sensors.

13.
Front Endocrinol (Lausanne) ; 15: 1344277, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601206

RESUMO

Background: Diabetic ketoacidosis (DKA) is a frequent acute complication of diabetes mellitus (DM). It develops quickly, produces severe symptoms, and greatly affects the lives and health of individuals with DM.This article utilizes machine learning methods to examine the baseline characteristics that significantly contribute to the development of DKA. Its goal is to identify and prevent DKA in a targeted and early manner. Methods: This study selected 2382 eligible diabetic patients from the MIMIC-IV dataset, including 1193 DM patients with ketoacidosis and 1186 DM patients without ketoacidosis. A total of 42 baseline characteristics were included in this research. The research process was as follows: Firstly, important features were selected through Pearson correlation analysis and random forest to identify the relevant physiological indicators associated with DKA. Next, logistic regression was used to individually predict DKA based on the 42 baseline characteristics, analyzing the impact of different physiological indicators on the experimental results. Finally, the prediction of ketoacidosis was performed by combining feature selection with machine learning models include logistic regression, XGBoost, decision tree, random forest, support vector machine, and k-nearest neighbors classifier. Results: Based on the importance analysis conducted using different feature selection methods, the top five features in terms of importance were identified as mean hematocrit (haematocrit_mean), mean hemoglobin (haemoglobin_mean), mean anion gap (aniongap_mean), age, and Charlson comorbidity index (charlson_comorbidity_index). These features were found to have significant relevance in predicting DKA. In the individual prediction using logistic regression, these five features have been proven to be effective, with F1 scores of 1.000 for hematocrit mean, 0.978 for haemoglobin_mean, 0.747 for age, 0.692 for aniongap_mean and 0.666 for charlson_comorbidity_index. These F1 scores indicate the effectiveness of each feature in predicting DKA, with the highest score achieved by mean hematocrit. In the prediction of DKA using machine learning models, including logistic regression, XGBoost, decision tree, and random forest demonstrated excellent results, achieving an F1 score of 1.000. Additionally, by applying feature selection techniques, noticeable improvements were observed in the experimental performance of the support vector machine and k-nearest neighbors classifier. Conclusion: The study found that hematocrit, hemoglobin, anion gap, age, and Charlson comorbidity index are closely associated with ketoacidosis. In clinical practice, these five baseline characteristics should be given with the special attention to achieve early detection and treatment, thus reducing the incidence of the disease.


Assuntos
Diabetes Mellitus , Cetoacidose Diabética , Humanos , Lactente , Cetoacidose Diabética/diagnóstico , Cetoacidose Diabética/epidemiologia , Cetoacidose Diabética/etiologia , Hemoglobinas
14.
Artigo em Inglês | MEDLINE | ID: mdl-38626418

RESUMO

The recent discovery of ferroelectricity in pure ZrO2 has drawn much attention, but the information storage and processing performances of ferroelectric ZrO2-based nonvolatile devices remain open for further exploration. Here, a ZrO2 (∼8 nm)-based ferroelectric capacitor using RuO2 oxide electrodes is fabricated, and the ferroelectric orthorhombic phase evolution under electric field cycling is studied. A ferroelectric remnant polarization (2Pr) of >30 µC/cm2, leakage current density of ∼2.79 × 10-8 A/cm2 at 1 MV/cm, and estimated polarization retention of >10 years are achieved. When the ferroelectric capacitor is connected with a transistor, a memory window of ∼0.8 V and eight distinct states can be obtained in such a ferroelectric field-effect transistor (FeFET). Through the conductance manipulation of the FeFET, a high object image recognition accuracy of ∼93.32% is achieved on the basis of the CIFAR-10 dataset in the convolutional neural network (CNN) simulation, which is close to the result of ∼94.20% obtained by floating-point-based CNN software. These results demonstrate the potential of ferroelectric ZrO2 devices for nonvolatile memory and artificial neural network computing.

15.
R Soc Open Sci ; 11(4): 231550, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38577210

RESUMO

Human sensorimotor decision making has a tendency to get 'stuck in a rut', being biased towards selecting a previously implemented action structure (hysteresis). Existing explanations propose this is the consequence of an agent efficiently modifying an existing plan, rather than creating a new plan from scratch. Instead, we propose that hysteresis is an emergent property of a system learning from the consequences of its actions. To examine this, 152 participants moved a cursor to a target on a tablet device while avoiding an obstacle. Hysteresis was observed when the obstacle moved sequentially across the screen between trials, whereby the participant continued moving around the same side of the obstacle despite it now requiring a larger movement than the alternative. Two further experiments (n = 20) showed an attenuation when time and resource constraints were eased. We created a simple computational model capturing probabilistic estimate updating that showed the same patterns of results. This provides, to our knowledge, the first computational demonstration of how sensorimotor decision making can get 'stuck in a rut' through the updating of the probability estimates associated with actions.

17.
J Thorac Dis ; 16(2): 1171-1179, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38505028

RESUMO

Background: The diagnosis, treatment, and prognosis of early postoperative constrictive pericarditis (EPCP) have not been discussed in depth. The objective of this study was to devise and propose a management strategy for EPCP. Methods: In this study, constrictive pericarditis (CP) within 6 months after cardiac surgery was defined as EPCP, and patients were divided into two groups based on intraoperative findings: a parietal thickening group and a visceral thickening group. Results: A total of 20 patients were included in this study, and the incidence rate of recurrent pericardiectomy was 0.32% among all patients undergoing cardiovascular surgery. EPCP after valve surgery occurred in 85.0% of patients. Pleural effusion was the most common preoperative symptom, occurring in 90% of patients. Pericardial thickening occurred in the visceral layer in seven cases and in the parietal layer in 13 cases. There were no differences in comorbidities, C-reactive protein (CRP) level, or erythrocyte sedimentation rate (ESR) between the two groups. Most patients with visceral thickening (83.3%) needed cardiopulmonary bypass (CPB) assistance during surgery and had a longer hospital stay than those with parietal thickening (52.8±21.8 vs. 34.9±13.8 days, P=0.049). Central venous pressure (CVP) was decreased in all patients after pericardiectomy (24.9±6.96 vs. 8.9±2.92 cmH2O, P<0.001), and the cardiac function improved significantly in patients with parietal thickening [New York Heart Association (NYHA) grade ≥ III accounted for 28.6% of patients]. The long-term survival rate of patients with parietal thickening was 92.3% and that of patients with visceral thickening was 57.1%, and there was no significant difference between them (P=0.056). Conclusions: Recurrent episodes of chest tightness, pleural effusion, and elevated CVP within 6 months after cardiac surgery should be considered highly suggestive of EPCP. There are few points of difference between pericarditis with thickening of the parietal and visceral layers. After failure of conservative medical treatment, pericardiectomy results in significant improvements in cardiac function and quality of life, especially in patients with thickening of the parietal layer.

18.
Front Pharmacol ; 15: 1348700, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38434699

RESUMO

Background: Previous studies have explored the median effective concentration (EC50) of ropivacaine for labor epidural analgesia in parturients with obesity. However, the clinical relevance of the 90% effective concentration (EC90) remains unclear. This study aimed to determine and compare the dose-response curve of epidural ropivacaine for labor analgesia between parturients with and without obesity. Methods: Parturients were divided into two groups based on body mass index (BMI): group N, consisting of parturients with BMI <30 kg/m2, and group O, consisting of parturients with BMI >30 kg/m2. Within each group, the patients were randomized to receive one of five concentrations (0.0375%, 0.075%, 0.1125%, 0.15%, or 0.1875%) of epidural ropivacaine for labor analgesia. Analgesia was induced with a loading dose of 15 mL of the assigned concentration. Visual analogue scale (VAS) scores were recorded at baseline and 30 min post-dose to calculate the response (%) using the formula [(baseline VAS pain score-VAS pain score at 30 min)/baseline VAS pain score] ×100%. The EC50 and EC90 values were determined via nonlinear regression analysis. Results: The EC50 and EC90 values of ropivacaine were 0.061% (95% confidence interval [CI], 0.056%-0.066%) and 0.177% (95% CI, 0.152%-0.206%) in group N and 0.056% (95% CI, 0.051%-0.061%) and 0.161% (95% CI, 0.138%-0.187%) in group O, respectively. No significant differences were observed in the EC50 and EC90 values between the two groups (p-values = 0.121 and 0.351, respectively. Conclusion: In conclusion, within the parameters of this study, our findings suggest that obesity, characterized by a mean BMI value of 30.9, does not significantly influence the EC50 and EC90 values of epidural ropivacaine for labor analgesia. Further investigations are warranted to elucidate the dose-response relationship between ropivacaine and obesity with higher BMI values. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=190747, Identifier ChiCTR2300073273.

19.
Opt Express ; 32(5): 7090-7104, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439399

RESUMO

We report a theoretical and experimental study on stimulated Brillouin scattering (SBS) suppression in a monolithic fiber amplifier with filtered and amplified pseudo-random binary sequence (PRBS) phase modulation. Theoretically, we use a time-dependent three-wave coupled nonlinear system considering both active fiber and passive fiber to describe the acoustic phonon, laser, and Stokes characteristics in a fiber amplifier. The SBS threshold power after filtered PRBS phase modulation is numerically evaluated to obtain the optimal parameters, and the time-averaged distributions of the counter-pump power, laser power, and Stokes power at different positions along the fiber length of the fiber system are simulated. Also, we established a four-stage fiber amplifier system to verify our theory. The configuration of the fiber amplifier system includes a filtered and amplified PRBS phase-modulated single-frequency fiber laser, a three-stage pre-amplifier, and a counter-pumping main stage, subsequently. 2.5 kW output power with an FWHM linewidth of 9.63 GHz is accomplished by a domestic ytterbium-doped double-clad fiber with core/cladding diameters of 20.2/400  µm. The reflectivity of the main stage is 0.049‰ at the maximum output power, which indicates the proposed architecture is under the SBS threshold. The experiments verify the accuracy of the theoretical model, which provides a reliable reference for evaluating the SBS suppression capability of the high-power narrow-linewidth fiber amplifier phase modulated by the filtered and amplified PRBS signal.

20.
Clin Transl Radiat Oncol ; 46: 100760, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38510980

RESUMO

Purpose: MR-guided radiotherapy (MRgRT) has the advantage of utilizing high soft tissue contrast imaging to track daily changes in target and critical organs throughout the entire radiation treatment course. Head and neck (HN) stereotactic body radiation therapy (SBRT) has been increasingly used to treat localized lesions within a shorter timeframe. The purpose of this study is to examine the dosimetric difference between the step-and-shot intensity modulated radiation therapy (IMRT) plans on Elekta Unity and our clinical volumetric modulated arc therapy (VMAT) plans on Varian TrueBeam for HN SBRT. Method: Fourteen patients treated on TrueBeam sTx with VMAT treatment plans were re-planned in the Monaco treatment planning system for Elekta Unity MR-Linac (MRL). The plan qualities, including target coverage, conformity, homogeneity, nearby critical organ doses, gradient index and low dose bath volume, were compared between VMAT and Monaco IMRT plans. Additionally, we evaluated the Unity adaptive plans of adapt-to-position (ATP) and adapt-to-shape (ATS) workflows using simulated setup errors for five patients and assessed the outcomes of our treated patients. Results: Monaco IMRT plans achieved comparable results to VMAT plans in terms of target coverage, uniformity and homogeneity, with slightly higher target maximum and mean doses. The critical organ doses in Monaco IMRT plans all met clinical goals; however, the mean doses and low dose bath volumes were higher than in VMAT plans. The adaptive plans demonstrated that the ATP workflow may result in degraded target coverage and OAR doses for HN SBRT, while the ATS workflow can maintain the plan quality. Conclusion: The use of Monaco treatment planning and online adaptation can achieve dosimetric results comparable to VMAT plans, with the additional benefits of real-time tracking of target volume and nearby critical structures. This offers the potential to treat aggressive and variable tumors in HN SBRT and improve local control and treatment toxicity.

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