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1.
Small ; 20(11): e2309454, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38098368

RESUMEN

The optimal treatment for tracheal tumors necessitates sequential tumor elimination and tracheal cartilage reconstruction. This study introduces an innovative inorganic nanosheet, MnO2 /PDA@Cu, comprising manganese dioxide (MnO2 ) loaded with copper ions (Cu) through in situ polymerization using polydopamine (PDA) as an intermediary. Additionally, a specialized methacrylic anhydride modified decellularized cartilage matrix (MDC) hydrogel with chondrogenic effects is developed by modifying a decellularized cartilage matrix with methacrylic anhydride. The MnO2 /PDA@Cu nanosheet is encapsulated within MDC-derived microneedles, creating a photothermal-controllable MnO2 /PDA@Cu-MDC microneedle. Effectiveness evaluation involved deep insertion of the MnO2 /PDA@Cu-MDC microneedle into tracheal orthotopic tumor in a murine model. Under 808 nm near-infrared irradiation, facilitated by PDA, the microneedle exhibited rapid overheating, efficiently eliminating tumors. PDA's photothermal effects triggered controlled MnO2 and Cu release. The MnO2 nanosheet acted as a potent inorganic nanoenzyme, scavenging reactive oxygen species for an antioxidant effect, while Cu facilitated angiogenesis. This intervention enhanced blood supply at the tumor excision site, promoting stem cell enrichment and nutrient provision. The MDC hydrogel played a pivotal role in creating a chondrogenic niche, fostering stem cells to secrete cartilaginous matrix. In conclusion, the MnO2 /PDA@Cu-MDC microneedle is a versatile platform with photothermal control, sequentially combining antitumor, antioxidant, pro-angiogenic, and chondrogenic activities to orchestrate precise tracheal tumor eradication and cartilage regeneration.


Asunto(s)
Nanopartículas , Neoplasias , Neoplasias de la Tráquea , Humanos , Ratones , Animales , Antioxidantes , Compuestos de Manganeso , Óxidos , Neoplasias/patología , Cartílago , Hidrogeles , Anhídridos
2.
Clin Radiol ; 79(8): e994-e1002, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38789330

RESUMEN

AIM: To develop and validate a deep learning (DL) algorithm for the automated detection and classification of carotid artery plaques (CAPs) on computed tomography angiography (CTA) images. MATERIALS AND METHODS: This retrospective study enrolled 400 patients (300 in the Center Ⅰ and 100 in Ⅱ). Three radiologists co-labeled CAPs, and their revised calcification status (noncalcified, mixed, and calcified) was regarded as ground truth. Center Ⅰ patients were randomly divided into training and internal validation datasets, while Center Ⅱ patients served as the external validation dataset. Carotid artery regions were segmented using a modified 3D-UNet network, followed by CAPs detection and classification using a ResUNet-based architecture in a two-step DL system. The DL model's detection and classification performance were evaluated on the validation dataset using precision-recall curve, free-response receiver operating characteristic (fROC) curve, Cohen's kappa, and ROC curve analysis. RESULTS: The DL model had achieved 83.4% sensitivity at 3.0 false positives (FPs)/CTA scan in internal validation and 78.9% in external validation. F1-scores were 0.764 and 0.769 at the optimal threshold, and area under fROC curves were 0.756 and 0.738, respectively, indicating good overall accuracy for CAP detection. The DL model also showed good performance for the ternary classification of CAPs, with Cohen's kappa achieved 0.728 and 0.703 in both validation datasets. CONCLUSION: This study demonstrated the feasibility of using a fully automated DL-based algorithm for the detection and ternary classification of CAPs, which could be helpful for the workloads of radiologists.


Asunto(s)
Angiografía por Tomografía Computarizada , Aprendizaje Profundo , Humanos , Angiografía por Tomografía Computarizada/métodos , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Estenosis Carotídea/diagnóstico por imagen , Arterias Carótidas/diagnóstico por imagen , Placa Aterosclerótica/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Sensibilidad y Especificidad
3.
Chaos ; 34(8)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39177957

RESUMEN

Dynamics and properties of breathers for the modified Korteweg-de Vries equations with negative cubic nonlinearities are studied. While breathers and rogue waves are absent in a single component waveguide for the negative nonlinearity case, coupling can induce regimes of modulation instabilities. Such instabilities are correlated with the existence of rogue waves and breathers. Similar scenarios have been demonstrated previously for coupled systems of nonlinear Schrödinger and Hirota equations. Both real- and complex-valued modified Korteweg-de Vries equations will be treated, which are applicable to stratified fluids and optical waveguides, respectively. One special family of breathers for coupled, complex-valued equations is derived analytically. Robustness and stability of breathers are studied computationally. Knowledge of the growth rates of modulation instability of plane waves provides an instructive prelude on the robustness of breathers to deterministic perturbations. A theoretical formulation of the linear instability of breathers will involve differential equations with periodic coefficient, i.e., a Floquet analysis. Breathers associated with larger eigenvalues of the monodromy matrix tend to suffer greater instability and increased tendency of distortion. Predictions based on modulation instability and Floquet analysis show excellent agreements. The same trend is obtained for simulations conducted with random noise disturbances. Linear approaches like modulation instabilities and Floquet analysis, thus, generate a very illuminating picture of the nonlinear dynamics.

4.
Chaos ; 34(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38231179

RESUMEN

The nonlinear Schrödinger equation possesses doubly periodic solutions expressible in terms of the Jacobi elliptic functions. Such solutions can be realized through doubly periodic patterns observed in experiments in fluid mechanics and optics. Stability and robustness of these doubly periodic wave profiles in the focusing regime are studied computationally by using two approaches. First, linear stability is considered by Floquet theory. Growth will occur if the eigenvalues of the monodromy matrix are of a modulus larger than unity. This is verified by numerical simulations with input patterns of different periods. Initial patterns associated with larger eigenvalues will disintegrate faster due to instability. Second, formation of these doubly periodic patterns from a tranquil background is scrutinized. Doubly periodic profiles are generated by perturbing a continuous wave with one Fourier mode, with or without the additional presence of random noise. Effects of varying phase difference, perturbation amplitude, and randomness are studied. Varying the phase angle has a dramatic influence. Periodic patterns will only emerge if the perturbation amplitude is not too weak. The growth of higher-order harmonics, as well as the formation of breathers and repeating patterns, serve as a manifestation of the classical problem of Fermi-Pasta-Ulam-Tsingou recurrence.

5.
Zhonghua Wai Ke Za Zhi ; 62(6): 598-605, 2024 Jun 01.
Artículo en Zh | MEDLINE | ID: mdl-38682632

RESUMEN

Objective: To investigate the effect of the ratio of the maximum diameter of aneurysm sac to age (R) on the long-term efficacy of endovascular aneurysm repair (EVAR) and open surgical repair (OSR) in patients with infrarenal abdominal aortic aneurysm (IAAA). Methods: This is a retrospective cohort study.The clinical data of 317 patients with IAAA who underwent surgical repair in the Department of Vascular Surgery,the Third Affiliated Hospital of Sun Yat-Sen University from January 2016 to October 2022 were retrospectively collected.There were 266 males and 51 females,aged (69.7±8.3) years (range:37 to 87 years).The R value of the patient was calculated and the receiver operating characteristic(ROC) curve was used to establish a model to calculate the optimal cut-off value.The propensity score matching method was used to match the baseline data of patients in the EVAR and OSR group by 3∶1 (the caliper value was 0.05),and the patients were stratified according to the cutoff value of R, and the postoperative efficacy and survival of the patients were analyzed.The primary endpoint was the total mortality rate,and the secondary endpoints included the occurrence of postoperative complications and reintervention.Pearson χ2 or Fisher 's exact test was used for categorical variables, and independent sample t test or Wilcoxon rank sum test was used for continuous variables to compare differences between groups.The survival curves of the two groups were described by Kaplan-Meier method. Results: After propensity score matching,198 cases were in the EVAR group and 66 cases were in the OSR group.The ROC model showed that the best cut-off value of R value was 0.90,and the two groups were divided into two layers:R<0.90 and R≥0.90.Among them,112 patients with R<0.90 (84 cases of EVAR,28 cases of OSR);there were 152 patients with R≥0.90 (114 cases of EVAR and 38 cases of OSR).The follow-up time was (23.6±1.6) months (range:1 to 70 months).In the R≥0.90 stratification,the total mortality (26.3% vs.5.3%,χ2=7.600,P=0.006),complication rate (44.7% vs.26.3%, χ2=4.025,P=0.045), and secondary intervention rate (31.6% vs.13.2%, χ2=4.910,P=0.027) in the EVAR group were higher than those in the OSR group.In the R<0.90 stratification,there was no significant difference in the total mortality rate (13.1% vs.10.7%, χ2=0.109,P=0.741), complication rate (28.6% vs.35.7%, χ2=0.507,P=0.477) and secondary intervention rate (14.3% vs.21.4%, χ2=0.353,P=0.552) between the two groups. Conclusions: When R≥0.90 in IAAA patients,OSR maybe more beneficial to patients in terms of survival rate,postoperative complication rate and secondary intervention rate than EVAR.When R<0.90,there are no significant differences in survival rate,complication rate and secondary intervention rate between the two surgical methods.


Asunto(s)
Aneurisma de la Aorta Abdominal , Procedimientos Endovasculares , Humanos , Aneurisma de la Aorta Abdominal/cirugía , Masculino , Femenino , Estudios Retrospectivos , Anciano , Procedimientos Endovasculares/métodos , Persona de Mediana Edad , Anciano de 80 o más Años , Resultado del Tratamiento , Adulto , Implantación de Prótesis Vascular/métodos , Factores de Edad , Puntaje de Propensión , Complicaciones Posoperatorias
6.
Clin Radiol ; 78(8): e552-e559, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37117048

RESUMEN

AIM: To develop a nomogram to predict lymphovascular invasion (LVI) in gastric cancer by integrating multiphase computed tomography (CT) radiomics and clinical risk factors. MATERIALS AND METHODS: One hundred and seventy-two gastric cancer patients (121 training and 51 validation) with preoperative contrast-enhanced CT images and clinicopathological data were collected retrospectively. The clinical risk factors were selected by univariate and multivariate regression analysis. Radiomic features were extracted and selected from the arterial phase (AP), venous phase (VP), and delayed phase (DP) CT images of each patient. Clinical risk factors, radiomic features, and integration of both were used to develop the clinical model, radiomic models, and nomogram, respectively. RESULTS: Radiomic features from AP (n=6), VP (n=6), DP (n=7) CT images and three selected clinical risk factors were used for model development. The nomogram showed better performance than the AP, VP, DP, and clinical models in the training and validation datasets, providing areas under the curves (AUCs) of 0.890 (95% CI: 0.820-0.940) and 0.885 (95% CI:0.765-0.957), respectively. All models indicated good calibration, and decision curve analysis proved that the net benefit of the nomogram was superior to that of the clinical and radiomic models throughout the vast majority of the threshold probabilities. CONCLUSIONS: The nomogram integrating multiphase CT radiomics and clinical risk factors showed favourable performance in predicting LVI of gastric cancer, which may benefit clinical practice.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/cirugía , Nomogramas , Estudios Retrospectivos , Área Bajo la Curva , Tomografía Computarizada por Rayos X
7.
J Dairy Sci ; 106(12): 8523-8537, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37641246

RESUMEN

Understanding consumers' purchase behaviors is fundamental to the success of the dairy industry. With its economic importance, the Chinese market is critical to dairy producers in most countries around the world. However, understanding consumers in this market is particularly challenging, as these consumers often have a different relationship with dairy products than consumers elsewhere in the world, given the country's historical dairy-related scandals. This special relationship can be characterized by what consumer behavior researchers call "high involvement," indicating that Chinese dairy consumers often attempt to reduce the level of risk associated with buying dairy products. Surprisingly, although this relationship affects several important aspects of purchase behavior, examination of the concept of involvement in the dairy sector has not been widely considered. Of note, there is no understanding of how Chinese consumers vary in their involvement levels and their implications on their dairy purchase behaviors. Nor have there been involvement-based insights provided on how dairy companies can position their marketing strategy to suit the needs of these consumers better. Thus, this study proposes a new approach to understanding Chinese consumer dairy decisions by introducing "consumer involvement" as a segmentation tool through which individuals' behaviors can be predicated according to their involvement profile. Based on an online survey administered in Shanghai using 1,073 dairy consumers, principal component analysis confirmed involvement with dairy is a multidimensional construct with the following 4 factors: pleasure value, symbolic value, risk importance, and risk probability. A 2-step cluster analysis identified 4 consumer clusters based on their involvement profile: face-concerned dairy lover, carefree dairy consumer, cautious dairy lover, and confused dairy consumer. According to a one-way ANOVA test and cross-tabulation with χ2 test, these consumer segments behave differently in relation to the extensiveness of decision making, cue utilization, trust of information sources, and consumption behavior. The outcomes in this paper further explain why efforts to restore consumer trust for dairy products do not work among some consumers, as individuals may exhibit diverse attitudes toward such information due to their heterogeneous involvement levels. The study also provides suggestions for market practitioners and organizations to develop effective target market strategies and policies according to different consumer clusters.


Asunto(s)
Comportamiento del Consumidor , Productos Lácteos , Humanos , China , Actitud , Encuestas y Cuestionarios
8.
Br Poult Sci ; 64(1): 90-99, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36093974

RESUMEN

1. In a previous high-throughput sequencing study, a novel circular RNA (circRNA) generated from a SUN domain containing ossification factor (SUCO) gene transcript (circSUCO) was differentially expressed during the embryonic muscle development. This study aimed to further explore the effect of circSUCO on chicken skeletal muscle development.2. The experiment analysed the expression patterns of circSUCO in Tianfu broilers and clarified its function in the chicken skeletal muscle satellite cells (SMSC) after circSUCO knockdown. The qPCR results showed circSUCO was highly expressed in skeletal muscle and has different expression levels during various development periods.3. Mechanistically, a series of in vitro experiments showed that circSUCO interference suppressed proliferation and differentiation of SMSC. In addition, it was observed that circSUCO competitively binds with microRNAs such as miR-15a, miR-15b-5p, and miR-15c-5p according to the dual-luciferase assay and qPCR.4. Correlation was positive between the circSUCO expression level and the ratio of the breast muscle. The results revealed that circSUCO could play a positive role in proliferation and differentiation of SMSC via sponging miR-15a, miR-15b-5p, and miR-15c-5p, hence, may contribute to skeletal muscle development in chicken.


Asunto(s)
MicroARNs , Células Satélite del Músculo Esquelético , Animales , Pollos/genética , Pollos/metabolismo , Células Satélite del Músculo Esquelético/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Diferenciación Celular/genética , Músculo Esquelético/metabolismo , Proliferación Celular/genética
9.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(2): 151-157, 2023 Feb 12.
Artículo en Zh | MEDLINE | ID: mdl-36740375

RESUMEN

Objective: To analyze the bronchoscopic manifestations and interventional treatment of pulmonary mucormycosis. Methods: Clinical data of patients with pulmonary mucormycosis undergoing bronchoscopy and interventional therapy in 4 tertiary general hospitals in China from May 2006 to May 2022 were retrospectively analyzed and the literature on the subject were reviewed. Results: The data of 10 patients with pathologically diagnosed pulmonary mucormycosis undergoing bronchoscopy and interventional therapy were collected, including 8 males and 2 females. The patients' age ranged from 21 to 72 (44±15) years. The underlying diseases included 6 cases of diabetes ketoacidosis, 3 cases of leukemia, 1 case after operation of lung cancer. Bronchoscopy showed that white viscous necrotic matters grew along the airway and blocked the airway in 9 cases, accompanied by airway bleeding in 3 cases, bloody secretion blocked the airway in 1 case, and bronchopulmonary cavity fistula in 2 cases. The biopsy histopathology of white necrotic matters showed that many mucor filaments were tangled together which were named mucormycelium. Among the 10 patients, 9 were treated with systemic drugs, including intravenous application of amphotericin B deoxycholate in 5 cases, intravenous application of amphotericin B liposome in 4 cases, oral posaconazole in 6 cases and intravenous injection in 1 case. Local drug therapy included aerosol inhalation of amphotericin B deoxycholate in 8 cases and local perfusion under bronchoscope in 5 cases. Bronchoscopic interventional therapy was used to remove mucormycelium in the bronchus, including cryotherapy in 8 cases, biopsy forceps in 7 cases, snare treatment in 2 cases and foreign body forceps in 2 cases. All 10 patients were clinical cured and with no death. Conclusions: Pulmonary mucormycosis is more common in immunocompromised hosts. Bronchoscopy often showed mucormycelium blocking the airway. Systemic and local drug therapy combined with bronchoscopic interventional therapy can achieve good clinical efficacy.


Asunto(s)
Neoplasias Pulmonares , Mucormicosis , Masculino , Femenino , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Mucormicosis/tratamiento farmacológico , Estudios Retrospectivos , Broncoscopía , Broncoscopios
10.
Zhonghua Wai Ke Za Zhi ; 61(6): 511-518, 2023 Jun 01.
Artículo en Zh | MEDLINE | ID: mdl-37088485

RESUMEN

Objective: To explore the development of the pancreatic surgeon technique in a high-volume center. Methods: A total of 284 cases receiving pancreatic surgery by a single surgeon from June 2015 to December 2020 were retrospectively included in this study. The clinical characteristics and perioperative medical history were extracted from the medical record system of Zhongshan Hospital,Fudan University. Among these patients,there were 140 males and 144 females with an age (M (IQR)) of 61.0 (16.8) years(range: 15 to 85 years). The "back-to-back" pancreatic- jejunal anastomosis procedure was used to anastomose the end of the pancreas stump and the jejunal wall. Thirty days after discharge,the patients were followed by outpatient follow-up or telephone interviews. The difference between categorical variables was analyzed by the Chi-square test or the CMH chi-square test. The statistical differences for the quantitative data were analyzed using one-way analysis of variance or Kruskal-Wallis H test and further analyzed using the LSD test or the Nemenyi test,respectively. Results: Intraoperative blood loss in pancreaticoduodenectomy between 2015 and 2020 were 300,100(100),100(100),100(0),100(200) and 150 (200) ml,respectively. Intraoperative blood loss in distal pancreatectomy was 250 (375),100 (50),50 (65), 50 (80),50 (50),and 50 (100) ml,respectively. Intraoperative blood loss did not show statistical differences in the same operative procedure between each year. The operative time for pancreaticoduodenectomy was respectively 4.5,5.0(2.0),5.5(0.8),5.0(1.3),5.0(3.3) and 5.0(1.0) hours in each year from 2015 to 2020,no statistical differences were found between each group. The operating time of the distal pancreatectomy was 3.8 (0.9),3.0 (1.5),3.0 (1.8),2.0 (1.1),2.0 (1.5) and 3.0(2.0) hours in each year,the operating time was obviously shorter in 2018 compared to 2015 (P=0.026) and 2020 (P=0.041). The median hospital stay in 2020 for distal pancreatectomy was 3 days shorter than that in 2019. The overall incidence of postoperative pancreatic fistula gradually decreased,with a incident rate of 50.0%,36.8%,31.0%,25.9%,21.1% and 14.8% in each year. During this period,in a total of 3,6,4,2,0 and 20 cases received laparoscopic operations in each year. The incidence of clinically relevant pancreatic fistula (grade B and C) gradually decreased,the incident rates were 0,4.8%,7.1%,3.4%,4.3% and 1.4%,respectively. Two cases had postoperative abdominal bleeding and received unscheduled reoperation. The overall rate of unscheduled reoperation was 0.7%. A patient died within 30 days after the operation and the overall perioperative mortality was 0.4%. Conclusion: The surgical training of a high-volume center can ensure a high starting point in the initial stage and steady progress of pancreatic surgeons,to ensure the safety of pancreatic surgery.


Asunto(s)
Neoplasias Pancreáticas , Cirujanos , Masculino , Femenino , Humanos , Fístula Pancreática/cirugía , Estudios Retrospectivos , Pérdida de Sangre Quirúrgica , Pancreatectomía/métodos , Pancreaticoduodenectomía , Complicaciones Posoperatorias , Hemorragia Posoperatoria , Neoplasias Pancreáticas/cirugía
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