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1.
Nano Lett ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38860507

RESUMEN

The majority of dislocations in nitride epilayers are edge threading dislocations (TDs), which diminish the performance of nitride devices. However, it is extremely difficult to reduce the edge TDs due to the lack of available slip systems. Here, we systematically investigate the formation mechanism of edge TDs and find that besides originating at the coalescence boundaries, these dislocations are also closely related to geometrical misfit dislocations at the interface. Based on this understanding, we propose a novel strategy to reduce the edge TD density of the GaN epilayer by nearly 1 order of magnitude via graphene-assisted remote heteroepitaxy. The first-principles calculations confirm that the insertion of graphene dramatically reduces the energy barrier required for interfacial sliding, which promotes a new strain release channel. This work provides a unique approach to directly suppress the formation of edge TDs at the source, thereby facilitating the enhanced performance of photoelectronic and electronic devices.

2.
Microb Pathog ; 187: 106515, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38160987

RESUMEN

In this study, a low molecular weight poly-d-mannose (LMWM) was separated from a mixed polysaccharide synthesized previously. Monosaccharide composition, Fourier-Transform infrared spectroscopy (FT-IR), periodate oxidation and smith degradation were determined. After safety evaluation, the inhibition of LMWM on the different biofilm formation stages of Salmonella enterica serovar Typhimurium (S. Typhimurium) was tested in vitro. Furthermore, the effect of LMWM on the adhesion of S. Typhimurium to Caco-2 cells and cell surface hydrophobicity (CSH) were observed. Results indicated that LMWM was a homopolysaccharide without cytotoxicity and hemolysis, containing both α-mannose and ß-mannose. It showed obvious anti-biofilm activity on S. Typhimurium and mainly activated on the initial adhesion and formation stage, even better than the commercial S. cerevisiae mannan (CM). LMWM inhibited the adhesion of S. Typhimurium on Caco-2 cells with the inhibition rate of 61.04 % at 2 mg/ml. Meanwhile, LMWM decreased the hydrophobicity of S. Typhimurium cell surface. In conclusion, the inhibitory effect on S. Typhimurium biofilm was not caused by bacteriostatic or bactericidal activity of LMWM. The specific anti-adhesion and the decrease of bacterial CSH by LMWM may closely relate to anti-biofilm mechanism. This study provides some supports for the application of LMWM as antibiotics alternative on S. Typhimurium in the future.


Asunto(s)
Manosa , Salmonella typhimurium , Humanos , Manosa/metabolismo , Manosa/farmacología , Células CACO-2 , Peso Molecular , Saccharomyces cerevisiae , Espectroscopía Infrarroja por Transformada de Fourier , Biopelículas
3.
Chemistry ; 30(45): e202401886, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-38857119

RESUMEN

Chalcogen bond (ChB) catalysis, as a new type in the field of non-covalent bond catalysis, has become a hot research topic in the field of organocatalysis in recent years. In the present work, we investigated the catalytic performance of a series of hypervalent ChB catalysis based on the intramolecular Aza-Michael reaction of aminochalcone. The reaction includes the carbon-nitrogen bond coupling step (key step) and the proton transfer step. The catalytic performance of mono-dentate pentafluorophenyl chalcogen bond donor ChB1 was comparable to that of bis-dentate chalcogen bond donor ChB4, and stronger than that of mono-dentate chalcogen bond donors ChB2 and ChB3. The formation of the chalcogen bond between the catalyst and the carbonyl oxygen atom of the reactant, causing the charge rearrangement of the reactant and C(1) charge of the -C-Ph group to become more positive, thereby the ChB catalysis promoted the nucleophile reaction. The electron density of the chalcogen bond of the pre-complex, the most positive electrostatic potentials of the catalyst, and the NPA charge of the key atom are proportional to the Gibbs energy barrier of the C-N bond coupling process, which provides an idea to predict the catalytic activity of the ChB catalysis.

4.
Catheter Cardiovasc Interv ; 103(6): 897-908, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38654635

RESUMEN

BACKGROUND: Acute kidney injury (AKI) is a frequent and potentially life-threatening complication after percutaneous coronary intervention (PCI) in patients with ST-segment-elevation myocardial infarction (STEMI). However, the relationship between obesity and the risk of AKI in this specific patient population has not been previously examined. METHODS: We queried the National Inpatient Sample (2016-2019) using ICD-10 codes to obtain a sample of adults with STEMI undergoing PCI. All patients were further subcategorized into obese and nonobese cohorts. The primary outcome was the incidence of AKI. Multivariate regression analysis was performed to assess the impact of obesity on AKI. The consistency of this correlation between subgroups was investigated using subgroup analysis and interaction testing. RESULTS: A total of 62,599 (weighted national estimate of 529,016) patients were identified, of which 9.80% (n = 6137) had AKI. Obesity comprised 19.78% (n = 1214) of the AKI cohort. Obese patients were on average younger, male, white, and had more comorbidities. Additionally, there was a significant positive association between obesity and AKI incidence (adjusted odds ratio [aOR]: 1.24, 95% confidence interval [CI]: 1.15-1.34), which was more pronounced in female patients (aOR: 1.56, 95% CI: 1.33-1.82, p < 0.001, p-interaction = 0.008). The AKI incidence in these patients increased steadily during the 4-year study period, and it was consistently higher in obese patients than in nonobese patients (p-trend < 0.001 for all). CONCLUSIONS: Obesity was independently associated with a greater risk of AKI among adults with STEMI undergoing PCI, particularly in female patients.


Asunto(s)
Lesión Renal Aguda , Bases de Datos Factuales , Obesidad , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Intervención Coronaria Percutánea/efectos adversos , Femenino , Masculino , Infarto del Miocardio con Elevación del ST/terapia , Infarto del Miocardio con Elevación del ST/epidemiología , Infarto del Miocardio con Elevación del ST/complicaciones , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/etiología , Persona de Mediana Edad , Factores de Riesgo , Obesidad/epidemiología , Obesidad/complicaciones , Estados Unidos/epidemiología , Incidencia , Anciano , Medición de Riesgo , Resultado del Tratamiento , Factores de Tiempo , Estudios Retrospectivos
5.
World J Urol ; 42(1): 148, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38478056

RESUMEN

OBJECTIVE: To assess the clinical efficacy of laparoscopic Lich-Gregoir (LLG) and transvesicoscopic Cohen reimplantation (TCR) in the treatment of vesicoureteral junction obstruction (VUJO) and vesicoureteral reflux (VUR). METHODS: This study retrospectively analyzed the clinical data of 66 pediatric patients with VUJO and VUR. They were classified into two groups, undergoing either the laparoscopic Lich-Gregoir operation (LLGO) (n = 35) or transvesicoscopic Cohen reimplantation operation (TCRO) (n = 31). The surgeries were performed between April 2018 and September 2022 at the First Affiliated Hospital of Guangxi Medical University, China. General characteristics, preoperative attributes, postoperative complications, renal function recovery, and improvement of hydronephrosis were compared between the two groups. RESULTS: All surgical procedures were successful with no requirement for reoperation. Both groups were comparable with respect to gender, affected side, weight, and postoperative complications. Nonetheless, the LLGO group contained a greater number of children younger than 12 months. The LLGO group demonstrated superiority over the TCRO group regarding the duration of the operation, intraoperative blood loss, and length of postoperative hospital stay. In contrast, postoperative complications, recovery of renal function, and hydronephrosis improvement did not exhibit statistically significant differences between the two groups. CONCLUSION: Both LLGO and TCRO were demonstrated to be precise, safe, and reliable surgical methods for treating pediatric VUJO and VUR. LLGO ureteral reimplantation offers particular advantages in selecting cases and appears more suitable for children younger than 12 months who have a small bladder capacity.


Asunto(s)
Hidronefrosis , Laparoscopía , Uréter , Reflujo Vesicoureteral , Niño , Humanos , Estudios Retrospectivos , Procedimientos Quirúrgicos Urológicos/métodos , China , Uréter/cirugía , Reflujo Vesicoureteral/cirugía , Resultado del Tratamiento , Laparoscopía/métodos , Reimplantación/métodos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/cirugía , Hidronefrosis/cirugía
6.
Vet Res ; 55(1): 68, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807225

RESUMEN

Pseudorabies virus (PRV) is recognized as the aetiological agent responsible for Aujeszky's disease, or pseudorabies, in swine populations. Rab6, a member of the small GTPase family, is implicated in various membrane trafficking processes, particularly exocytosis regulation. Its involvement in PRV infection, however, has not been documented previously. In our study, we observed a significant increase in the Rab6 mRNA and protein levels in both PK-15 porcine kidney epithelial cells and porcine alveolar macrophages, as well as in the lungs and spleens of mice infected with PRV. The overexpression of wild-type Rab6 and its GTP-bound mutant facilitated PRV proliferation, whereas the GDP-bound mutant form of Rab6 had no effect on viral propagation. These findings indicated that the GTPase activity of Rab6 was crucial for the successful spread of PRV. Further investigations revealed that the reduction in Rab6 levels through knockdown significantly hampered PRV proliferation and disrupted virus assembly and egress. At the molecular level, Rab6 was found to interact with the PRV glycoproteins gB and gE, both of which are essential for viral assembly and egress. Our results collectively suggest that PRV exploits Rab6 to expedite its assembly and egress and identify Rab6 as a promising novel target for therapeutic treatment for PRV infection.


Asunto(s)
Herpesvirus Suido 1 , Seudorrabia , Liberación del Virus , Proteínas de Unión al GTP rab , Animales , Herpesvirus Suido 1/fisiología , Herpesvirus Suido 1/genética , Porcinos , Proteínas de Unión al GTP rab/metabolismo , Proteínas de Unión al GTP rab/genética , Ratones , Seudorrabia/virología , Ensamble de Virus/fisiología , Enfermedades de los Porcinos/virología , Línea Celular
7.
Fish Shellfish Immunol ; 145: 109364, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38199264

RESUMEN

Micropterus salmoides rhabdovirus (MSRV) is one of the main pathogens of largemouth bass, leading to serious economic losses. The G protein, as the only envelope protein present on the surface of MSRV virion, contains immune-related antigenic determinants, thereby becoming the primary target for the design of MSRV vaccines. Here, we displayed the G protein on the surface of yeast cells (named EBY100/pYD1-G) and conducted a preliminary assessment of the protective efficacy of the recombinant yeast vaccine. Upon oral vaccination, a robust immune response was observed in systemic and mucosal tissue. Remarkably, following the MSRV challenge, the relative percent survival of EBY100/pYD1-G treated largemouth bass significantly increased to 66.7 %. In addition, oral administration inhibited viral replication and alleviated the pathological symptoms of MSRV-infected largemouth bass. These results suggest that EBY100/pYD1-G could be used as a potential oral vaccine against MSRV infection.


Asunto(s)
Lubina , Enfermedades de los Peces , Rhabdoviridae , Animales , Saccharomyces cerevisiae , Vacunación , Proteínas Fúngicas , Vacunas Sintéticas
8.
Nanotechnology ; 35(29)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38593759

RESUMEN

Herein, we employ molecular dynamics simulations to decode the friction properties and phonon energy dissipation between black phosphorus layers. The observations reveal the influence of three factors, temperature, velocity, and normal load, on the friction force of monolayer/bilayer black phosphorus. Specifically, friction is negatively correlated with layer thickness and temperature, and positively correlated with velocity and normal load. The change in friction force is further explained in terms of frictional energy dissipation, and supplemented by the height of potential barriers as well as the number of excited phonons. From the phonon spectrum analysis, the phonon number at the contact interface is found to be higher than that at the non-contact interface. This is due to the larger distance of the contact interface atoms deviate from their equilibrium positions, resulting in higher total energy generated by more intense oscillations, and therefore contributes greater to friction.

9.
Environ Sci Technol ; 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38344765

RESUMEN

Volatile sulfur compounds, such as dimethyl sulfide (DMS), carbonyl sulfide (OCS), and carbon disulfide (CS2), have significant implications for both atmospheric chemistry and climate change. Despite the crucial role of oceans in regulating their atmospheric budgets, our comprehension of their cycles in seawater remains insufficient. To address this gap, a field investigation was conducted in the western North Pacific to clarify the sources, sinks, and biogeochemical controls of these gases in two different marine environments, including relatively eutrophic Kuroshio-Oyashio extension (KOE) and oligotrophic North Pacific subtropical gyre. Our findings revealed higher concentrations of these gases in both seawater and the atmosphere in the KOE compared to the subtropical gyre. In the KOE, nutrient-rich upwelling stimulated rapid DMS biological production, while reduced seawater temperatures hindered the removal of OCS and CS2, leading to their accumulation. Furthermore, we have quantitatively evaluated the relative contribution of each pathway to the source and sink of DMS, OCS, and CS2 within the mixed layer and identified vertical exchange as a potential sink in most cases, transporting substantial amounts of these gases from the mixed layer to deeper waters. This research advances our understanding of sulfur gas source-sink dynamics in seawater, contributing to the assessment of their marine emissions and atmospheric budgets.

10.
Artículo en Inglés | MEDLINE | ID: mdl-38780349

RESUMEN

In recent years, gut microbiota has become a hot topic in the fields of medicine and life sciences. Short-chain fatty acids (SCFAs), the main metabolites of gut microbiota produced by microbial fermentation of dietary fiber, play a vital role in healthy and ill hosts. SCFAs regulate the process of metabolism, immune, and inflammation and have therapeutic effects on gastrointestinal and neurological disorders, as well as antitumor properties. This review summarized the production, distribution, and molecular mechanism of SCFAs, as well as their mechanisms of action in healthy and ill hosts. In addition, we also emphasized the negative effects of SCFAs, aiming to provide the public with a more comprehensive understanding of SCFAs.

11.
J Phys Chem A ; 128(28): 5473-5480, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38968435

RESUMEN

Liquid-phase synthesis of atomically precise nanoclusters has experienced rapid development recently, where polar solvents are indispensable in such a process. However, the regulation effect of solvents on the structural and electronic properties of different metal clusters and cluster assembly materials is still not well understood. Herein, a comprehensive density functional theory calculation has been performed to explore the solvation effect on heteroatom-doped endohedral gold clusters that always have remarkable stabilities and tunable electronic structures. The solvation free energy of the M@Au12 clusters (M = Cr, Mo, W, Co, Rh, Ir, Cu, Ag, and Au) was found to be related to the charge distribution of the central doped-atom M and the outer Au12 cage. Moreover, the aqueous solvent was observed to be able to increase the adsorption capacity of M@Au12 to O2 following the activation of O2 through the charge transfer from M@Au12 to O2, in which the transferred electrons occupy the π antibonding orbital of O2. In addition, the water solvent can also improve the hydrogenation reaction of O2 to form OOH over M@Au12, where the activation energy barrier for this process is very low with the participation of the solvent. Considering the importance of solvents in the liquid-phase synthesis of atomically precise clusters, these findings highlighted here could provide valuable theoretical guidance in potential applications of functional gold nanoclusters, especially in the liquid-phase cluster catalysis.

12.
J Phys Chem A ; 128(27): 5298-5306, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38917472

RESUMEN

The identification of the non-noble metal constituted TaO cluster as a potential analogue to the noble metal Au is significant for the development of tailored materials. It leverages the superatom concept to engineer properties with precision. However, the impact of incrementally integrating TaO units on the electronic configurations and properties within larger TaO-based clusters remains to be elucidated. By employing the density functional theory calculations, the global minima and low-lying isomers of the TanOn (n = 2-5) clusters were determined, and their structural evolution was disclosed. In the cluster series, Ta5O5 was found to possess the highest electron affinity (EA) with a value of 2.14 eV, based on which a dual external field (DEF) strategy was applied to regulate the electronic property of the cluster. Initially, the electron-withdrawing CO ligand was affixed to Ta5O5, followed by the application of an oriented external electric field (OEEF). The CO ligation was found to be able to enhance the Ta5O5 cluster's electron capture capability by adjusting its electron energy levels, with the EA of Ta5O5(CO)4 peaking at 2.58 eV. Subsequently, the introduction of OEEF further elevated the EA of the CO-ligated cluster. Notably, OEEF, when applied along the +x axis, was observed to sharply increase the EA to 3.26 eV, meeting the criteria for superhalogens. The enhancement of EA in response to OEEF intensity can be quantified as a functional relationship. This finding highlights the advantage of OEEF over conventional methods, demonstrating its capacity for precise and continuous modulation of cluster EAs. Consequently, this research has adeptly transformed tantalum oxide clusters into superhalogen structures, underscoring the effectiveness of the DEF strategy in augmenting cluster EAs and its promise as a viable tool for the creation of superhalogens.

13.
Artículo en Inglés | MEDLINE | ID: mdl-38581328

RESUMEN

Objective: The measurement of the right and left axillary arteries and aortic arch and their vessels by multi-row spiral CT angiography provides the basis for clinical catheter selection and depth for axillary artery placement. This study reported the clinical experience of 7 patients who successfully underwent ultrasound-guided percutaneous axillary artery cannulation for veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Methods: Patients who had CT angiography of the thoracic aorta at our institution between January 2020 and March 2022 were assessed for eligibility and included. The diameters of the cephalic trunk (D1), right common carotid artery (D2), right axillary artery (D3), left common carotid artery (D4), left axillary artery opening (D5), right axillary artery cannulation length (L1), and left axillary artery cannulation length (L2) were measured. The tangential angles α, ß, and γ of the cephalic trunk, left common carotid artery and left subclavian and aorta was measured using an automatic angle-forming tool. The decision to use a 15F cannula for ultrasound-guided percutaneous axillary artery cannulation in veno-arterial extracorporeal membrane oxygenation (VA-ECMO) aims to achieve optimal vascular access. This cannula size strikes a balance, providing sufficient blood flow rates for ECMO support while minimizing the risk of complications associated with larger cannulas. Precise measurements of arterial dimensions, including the cephalic trunk, common carotid arteries, and axillary arteries, play a crucial role in guiding catheter selection and determining the depth of axillary artery placement. These measurements allow for tailored approaches based on individual patient characteristics, enhancing the safety and efficacy of the intervention. Additionally, measuring tangential angles (α, ß, and γ) provides insights into arterial alignment, optimizing the cannula trajectory for efficient blood flow. The use of an automatic angle-forming tool enhances measurement precision, contributing to procedural accuracy, minimizing complications, and ensuring the success of ultrasound-guided percutaneous axillary artery cannulation. In summary, the choice of a 15F cannula and precise measurements are essential components of the methodology, emphasizing safety, efficacy, and personalized approaches in VA-ECMO. From March to June 2022, 7 patients (6 males and 1 female) in our intensive care medicine department underwent successful ultrasound-guided percutaneous axillary artery cannulation for VA-ECMO with 15F cannula, including 3 cases with extracorporeal cardiopulmonary resuscitation (ECPR) and 4 cases with circulatory collapse. Results: 292 patients met the study criteria, 215 males and 77 females, with a mean age of 67.2±14.2 years. The measurements showed that D1 was (13.1±2.0) mm, D2 was (8.8±2.5) mm, D3 was (6.1±1.2) mm, D4 was (8.3±3.5) mm, D5 was (6.1±1.1) mm, L1 was (114.1±17.8) mm, and L2 was (128.4±20.2) mm. The tangential angles α of the cephalic trunk left common carotid artery and left subclavian artery to the aorta were (43.8°±17.1°), ß was (50.7°±14.8°), and γ was (62.4°±19.1°). Males had significantly wider D3 and D5, longer L1 and L2, and smaller gamma angles than females (P < .05). Three ECPR cases showed no recovery of the spontaneous heartbeat with femoral artery cannulation for VA-ECMO but recovered spontaneous heartbeat after axillary artery cannulation for VA-ECMO was adopted. The measurements in this study have important implications for veno-arterial extracorporeal membrane oxygenation (VA-ECMO) procedures. They provide crucial information about arterial dimensions, including the cephalic trunk, common carotid arteries, and axillary arteries. This information guides clinicians in selecting catheters and determining the ideal depth for percutaneous axillary artery cannulation during ECMO interventions. Notable gender differences in arterial dimensions highlight the need for personalized approaches in ECMO procedures. Customizing catheter choices and cannulation depth based on individual patient characteristics, informed by these measurements, improves the safety and effectiveness of the intervention. The measured tangential angles (α, ß, and γ) offer insights into arterial alignment, crucial for optimizing cannula trajectory and ensuring proper alignment for efficient blood flow. The use of an automatic angle-forming tool enhances measurement precision, contributing to procedural accuracy and minimizing the risk of complications during ECMO procedures. In summary, these measurements directly enhance the precision and safety of VA-ECMO procedures, underscoring the importance of personalized approaches based on individual anatomical variations and improving overall intervention success and outcomes. Conclusion: Ultrasound-guided percutaneous axillary artery cannulation for VA-ECMO with a 15F cannula is clinically feasible. Axillary artery cannulation for VA-ECMO contributes to the restoration of spontaneous heartbeat in ECPR patients more than femoral artery cannulation, and the possible mechanism is a better improvement of coronary blood flow. However, the study has limitations, including a modest sample size and a single-center, retrospective design, impacting its generalizability. To validate and extend these findings, further research with larger and diverse cohorts, including prospective investigations, is necessary to ensure their applicability across various clinical settings and patient demographics in VA-ECMO.

14.
BMC Surg ; 24(1): 74, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38424546

RESUMEN

BACKGROUND: Nowadays, both lateral mass screw (LMS) and pedicle screw were effective instrumentation for posterior stabilization of cervical spine. This study aims to evaluate the feasibility of a new free-hand technique of C7 pedicle screw insertion without fluoroscopic guidance for cervical spondylotic myelopathy (CSM) patients with C3 to C6 instrumented by lateral mass screws. METHODS: A total of 53 CSM patients underwent lateral mass screws instrumentation at C3 to C6 levels and pedicle screw instrumentation at C7 level were included. The preoperative 3-dimenional computed tomography (CT) reconstruction images of cervical spine were used to determine 2 different C7 pedicle screw trajectories. Trajectory A passed through the axis of the C7 pedicle while trajectory B selected the midpoint of the base of C7 superior facet as the entry point. All these 53 patients had the C7 pedicle screw inserted through trajectory B by free-hand without fluoroscopic guidance and the postoperative CT images were obtained to evaluate the accuracy of C7 pedicle screw insertion. RESULTS: Trajectory B had smaller transverse angle, smaller screw length, and smaller screw width but both similar sagittal angle and similar pedicle height when compared with trajectory A. A total of 106 pedicle screws were inserted at C7 through trajectory B and only 8 screws were displaced with the accuracy of screw placement as high as 92.5%. CONCLUSION: In CSM patients with C3 to C6 instrumented by LMS, using trajectory B for C7 pedicle screw insertion is easy to both identify the entry point and facilitate the rod insertion.


Asunto(s)
Tornillos Pediculares , Enfermedades de la Médula Espinal , Fusión Vertebral , Humanos , Estudios Retrospectivos , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/cirugía , Fusión Vertebral/métodos , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía
15.
J Xray Sci Technol ; 32(2): 271-283, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38217629

RESUMEN

Accurate segmentation of industrial CT images is of great significance in industrial fields such as quality inspection and defect analysis. However, reconstruction of industrial CT images often suffers from typical metal artifacts caused by factors like beam hardening, scattering, statistical noise, and partial volume effects. Traditional segmentation methods are difficult to achieve precise segmentation of CT images mainly due to the presence of these metal artifacts. Furthermore, acquiring paired CT image data required by fully supervised networks proves to be extremely challenging. To address these issues, this paper introduces an improved CycleGAN approach for achieving semi-supervised segmentation of industrial CT images. This method not only eliminates the need for removing metal artifacts and noise, but also enables the direct conversion of metal artifact-contaminated images into segmented images without the requirement of paired data. The average values of quantitative assessment of image segmentation performance can reach 0.96645 for Dice Similarity Coefficient(Dice) and 0.93718 for Intersection over Union(IoU). In comparison to traditional segmentation methods, it presents significant improvements in both quantitative metrics and visual quality, provides valuable insights for further research.


Asunto(s)
Artefactos , Tomografía Computarizada por Rayos X , Tomografía Computarizada por Rayos X/métodos , Procesamiento de Imagen Asistido por Computador/métodos
16.
Eur J Orthop Surg Traumatol ; 34(5): 2421-2427, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38627286

RESUMEN

PURPOSE: To compare clinical outcomes of high tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) for anterior medial osteoarthritis (AMOA) as well as offer surgical recommendations through age stratification. METHODS: Between May 2019 and May 2021, 68 cross-indicated AMOA patients were analyzed. The patients were divided into HTO and UKA groups and further into two age groups of 55-60 and 60-65 years. Additionally, general data, visual analog scale (VAS) score, and Hospital for Special Surgery knee score (HSS) were analyzed. RESULTS: All the patients were followed up for 18 months. Knee joint HSS significantly improved, and VAS score decreased in both groups (P < 0.05). In the 55-60 age group, HTO showed superior knee HSS at 1 and 3 months (P < 0.05), with no significant difference at 6, 12, and 18 months. HTO had a significantly lower VAS score at one month, and the VAS scores of the two groups decreased gradually with no significant difference. In the 60-65 age group, the UKA group showed superior knee joint HSS at one month, with no significant difference at 3, 6, 12, and 18 months. The UKA group had a significantly lower VAS score at one month, and both groups' VAS scores decreased gradually with no significant difference. CONCLUSION: Both methods yield satisfactory results for AMOA cross-indications, improving knee joint function. The observed recovery trends have implications for personalized surgical recommendations, guiding interventions based on age-specific considerations for optimal outcomes in anterior medial osteoarthritis cases.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla , Osteotomía , Humanos , Osteoartritis de la Rodilla/cirugía , Persona de Mediana Edad , Femenino , Masculino , Anciano , Factores de Edad , Artroplastia de Reemplazo de Rodilla/métodos , Osteotomía/métodos , Tibia/cirugía , Resultado del Tratamiento , Dimensión del Dolor , Escala Visual Analógica
17.
BMC Psychol ; 12(1): 327, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38835103

RESUMEN

BACKGROUND AND RESEARCH OBJECTIVES: Given the enduring popularity of higher education, there has been considerable attention on the correlation between college students' engagement in sports and their academic stress levels. This study seeks to delve deeply into how university physical education fosters academic performance by influencing students' sports interests, particularly in enhancing their psychological resilience to mitigate academic pressure. Through this investigation, the aim is to offer both theoretical underpinnings and empirical evidence to support the holistic enhancement of higher education. RESEARCH METHODS: Initially, this study undertakes an analysis of the fundamental relationship between college students' physical activities and their experience of academic stress. Subsequently, utilizing a structural equation model, specific research models and hypotheses are formulated. These are then examined in detail through the questionnaire method to elucidate the mechanism by which college sports interests alleviate academic stress. RESEARCH FINDINGS: The study reveals a significant positive correlation between psychological resilience and academic stress, indicating that a robust psychological resilience can effectively diminish academic pressure. Furthermore, both the sports atmosphere and sports interest are found to exert a notable positive impact on academic stress, mediated by the variable of psychological toughness. This underscores the pivotal role of physical education in fostering positive psychological traits and enhancing academic achievement. CONCLUSION: This study underscores the central importance of cultivating and nurturing college students' sports interests, as well as fostering a conducive sports atmosphere, in fortifying psychological resilience and mitigating academic pressure. By offering novel perspectives and strategies for alleviating the academic stress faced by college students, this study contributes valuable theoretical insights and practical experiences to the broader development of higher education.


Asunto(s)
Resiliencia Psicológica , Deportes , Estrés Psicológico , Estudiantes , Humanos , Estrés Psicológico/psicología , Estudiantes/psicología , Estudiantes/estadística & datos numéricos , Masculino , Universidades , Deportes/psicología , Femenino , Adulto Joven , Adulto , Rendimiento Académico/psicología , Encuestas y Cuestionarios , Adolescente
18.
Sci Rep ; 14(1): 4565, 2024 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-38403645

RESUMEN

The benign and malignant status of solitary pulmonary nodules (SPNs) is a key determinant of treatment decisions. The main objective of this study was to validate the efficacy of machine learning (ML) models featured with dual-layer detector spectral computed tomography (DLCT) parameters in identifying the benign and malignant status of SPNs. 250 patients with pathologically confirmed SPN were included in this study. 8 quantitative and 16 derived parameters were obtained based on the regions of interest of the lesions on the patients' DLCT chest enhancement images. 6 ML models were constructed from 10 parameters selected after combining the patients' clinical parameters, including gender, age, and smoking history. The logistic regression model showed the best diagnostic performance with an area under the receiver operating characteristic curve (AUC) of 0.812, accuracy of 0.813, sensitivity of 0.750 and specificity of 0.791 on the test set. The results suggest that the ML models based on DLCT parameters are superior to the traditional CT parameter models in identifying the benign and malignant nature of SPNs, and have greater potential for application.


Asunto(s)
Neoplasias Pulmonares , Nódulo Pulmonar Solitario , Humanos , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/patología , Diagnóstico Diferencial , Tomografía Computarizada por Rayos X/métodos , Curva ROC , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología
19.
Front Oncol ; 14: 1337219, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38380369

RESUMEN

Background: Laparoscopic total mesorectal excision (LaTME) is standard surgical methods for rectal cancer, and LaTME operation is a challenging procedure. This study is intended to use machine learning to develop and validate prediction models for surgical difficulty of LaTME in patients with rectal cancer and compare these models' performance. Methods: We retrospectively collected the preoperative clinical and MRI pelvimetry parameter of rectal cancer patients who underwent laparoscopic total mesorectal resection from 2017 to 2022. The difficulty of LaTME was defined according to the scoring criteria reported by Escal. Patients were randomly divided into training group (80%) and test group (20%). We selected independent influencing features using the least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression method. Adopt synthetic minority oversampling technique (SMOTE) to alleviate the class imbalance problem. Six machine learning model were developed: light gradient boosting machine (LGBM); categorical boosting (CatBoost); extreme gradient boost (XGBoost), logistic regression (LR); random forests (RF); multilayer perceptron (MLP). The area under receiver operating characteristic curve (AUROC), accuracy, sensitivity, specificity and F1 score were used to evaluate the performance of the model. The Shapley Additive Explanations (SHAP) analysis provided interpretation for the best machine learning model. Further decision curve analysis (DCA) was used to evaluate the clinical manifestations of the model. Results: A total of 626 patients were included. LASSO regression analysis shows that tumor height, prognostic nutrition index (PNI), pelvic inlet, pelvic outlet, sacrococcygeal distance, mesorectal fat area and angle 5 (the angle between the apex of the sacral angle and the lower edge of the pubic bone) are the predictor variables of the machine learning model. In addition, the correlation heatmap shows that there is no significant correlation between these seven variables. When predicting the difficulty of LaTME surgery, the XGBoost model performed best among the six machine learning models (AUROC=0.855). Based on the decision curve analysis (DCA) results, the XGBoost model is also superior, and feature importance analysis shows that tumor height is the most important variable among the seven factors. Conclusions: This study developed an XGBoost model to predict the difficulty of LaTME surgery. This model can help clinicians quickly and accurately predict the difficulty of surgery and adopt individualized surgical methods.

20.
J Inflamm Res ; 17: 3079-3092, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774444

RESUMEN

Background: Hypertrophic cardiomyopathy (HCM) is a dominantly inherited disease associated with sudden immune cell associations that remain unclear. The aim of this study was to comprehensively screen candidate markers associated with HCM and immune cells and explore potential pathogenic pathways. Methods: First, download the GSE32453 dataset to identify differentially expressed genes (DEGs) and perform Gene Ontology and pathway enrichment analysis using DAVID and GSEA. Next, construct protein-protein interaction (PPI) networks using String and Cytoscape to identify hub genes. Afterward, use CIBERSORT to determine the proportion of immune cells attributed to key genes in HCM and conduct ROC analysis based on the external dataset GSE36961 to evaluate their diagnostic value. Finally, validate the expression of key genes in the hypertrophic cardiomyocyte model through qRT-PCR using data from the HPA database. Results: Comprehensive analysis revealed that there were 254 upregulated genes and 181 downregulated genes in HCM. The enrichment study underscored pathways of inflammatory signaling, including MAPK and PI3K-Akt pathways. Pathways abundant in genes associated with HCM encompassed myocardial contraction and NADH dehydrogenase activity. Additionally, the analysis of immune infiltration revealed a notable increase in macrophages, NK cells, and monocytes in the HCM group, showing statistically significant variances in CD4 memory resting T cell infiltration when compared to the healthy control group. Within the validation dataset GSE36961, the Area Under the Curve (AUC) scores for eight crucial genes (FOS, CD86, CD68, BDNF, PIK3R1, PLEK, RAC2, CCL2) each exceeded 0.8. The HPA database revealed the positioning traits and paths of these eight crucial genes in smooth muscle cells, myocardial cells, and fibroblasts. The outcomes of the qRT-PCR were aligned with the sequencing findings. Conclusion: Bioinformatics analysis unveiled pivotal genes, pathways, and immune involvement, illuminating the molecular underpinnings of HCM. These findings suggest promising therapeutic targets for clinical applications.

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