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1.
Nanotechnology ; 35(17)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-37832530

RESUMO

In the face of increasing energy demand, the approach of transformation that combines energy restructuring and environmental governance has become a popular research direction. As an important part of electrocatalytic reactions for gas molecules, reduction reactions of oxygen (ORR) and carbon dioxide (CO2RR) are very indispensable in the field of energy conversion and storage. However, the non-interchangeability and irreversibility of electrode materials have always been a challenge in electrocatalysis. Hereon, nickel and nitrogen decorated biomass carbon-based materials (Ni/N-BC) has been prepared by high temperature pyrolysis using agricultural waste straw as raw material. Surprisingly, it possesses abundant active sites and specific surface area as a bifunctional electrocatalyst for ORR and CO2RR. The three-dimensional porous cavity structure for the framework of biomass could not only provide a strong anchoring foundation for the active site, but also facilitate the transport and enrichment of reactants around the site. In addition, temperature modulation during the preparation process also optimizes the composition and structure of biomass carbon and nitrogen. Benefit from above structure and morphology advantages, Ni/N-BC-800 exhibits the superior electrocatalytic activity for both ORR and CO2RR simultaneously. More specifically, Ni/N-BC-800 exhibits satisfactory ORR activity in terms of initial potential and half wave potential, while also enables the production of CO under high selective. The research results provide ideas for the development and design of electrode materials and green electrocatalysts, and also expand new applications of agricultural waste in fields such as energy conversion, environmental protection, and resource utilization.

2.
Acta Radiol ; 64(2): 821-828, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35291856

RESUMO

BACKGROUND: Ovarian tumors (OTs) are common gynecological tumors in women. It is very important to correctly distinguish benign and malignant OTs. PURPOSE: To assess the diagnostic performance of the American College of Radiology (ACR) Ovarian-Adnexal Reporting and Data System (O-RADS) and evaluate the clinical value of O-RADS combined with serum carbohydrate antigen 125 (CA125) and human epididymis protein 4 (HE4) in differentiating benign from malignant OTs. MATERIAL AND METHODS: A retrospective analysis was performed on 431 cases including pathology and clinical data. The receiver operating characteristic (ROC) curve was drawn, and sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated. RESULTS: In premenopausal women, O-RADS and O-RADS combined with serum CA125 and HE4 showed sensitivity at 92.2% and 94.8%, specificity at 91.8% and 93.4%, and accuracy at 91.9% and 93.8%, respectively. In postmenopausal women, the sensitivity of O-RADS, O-RADS combined with serum CA125 and HE4 was 94.8% and 95.8%, specificity was 83.9% and 93.6%, and accuracy was 90.5% and 95.6%, respectively. The sensitivity, specificity, and accuracy of O-RADS combined with CA125 and HE4 in premenopausal and postmenopausal women were higher than that of O-RADS (P<0.05). CONCLUSION: O-RADS has high diagnostic performance in OTs. When O-RADS is combined with CA125 and HE4 in the diagnosis of OTs, the sensitivity and specificity are improved, which is helpful to improve the diagnostic efficiency of OTs and has high clinical application value.


Assuntos
Neoplasias Ovarianas , Proteínas , Feminino , Humanos , Proteínas/análise , Proteínas/metabolismo , Estudos Retrospectivos , Neoplasias Ovarianas/diagnóstico por imagem , Sensibilidade e Especificidade , Curva ROC , Antígeno Ca-125 , Biomarcadores Tumorais
3.
J Ultrasound Med ; 40(11): 2441-2448, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33433027

RESUMO

OBJECTIVES: To evaluate shear wave elastography (SWE) technology diagnosis value of endometrial cancer (EC) and atypical endometrial hyperplasia (AEH), and to establish predictive logistic regression models for the diagnosis of EC and AEH. METHODS: Clinical information collection, transvaginal conventional ultrasonography, and SWE check were performed on 122 patients, who were perimenopausal or postmenopausal vaginal bleeding with ≥4.5 mm thick endometrium. The maximal (Emax) and mean (Emean) of Young's modulus for the endometrium were obtained. Using pathology as the gold standard, ROC curves were plotted to evaluate Young's modulus on the diagnostic effectiveness of EC and AEH. Single-factor analysis and bivariate logistic regression methods were applied to assess the clinical variables, transuaginal conventional ultrasonography variables, and Young's modulus on the identification of EC and AEH. RESULTS: Out of 122 cases of endometrial lesions, 85 cases were benign lesions, and the remaining 37 cases were EC and AEH. The Emax and Emean for the benign group were 29.80 ± 11.40 and 17.96 ± 8.05 kPa, respectively. The Emax and Emean values for EC and AEH group were 59.49 ± 16.95 and 38.46 ± 17.10 kPa, respectively. Emax and Emean for both groups were statistically significant, with p <.001. In the logistical regression analysis, endometrial thickness, Color score, and Young's modulus were identified as independent risk factors for EC and AEH. CONCLUSIONS: SWE technology plays an important role in the diagnosis of EC and AEH, and the diagnostic effectiveness would be higher when combined with conventional ultrasonography.


Assuntos
Técnicas de Imagem por Elasticidade , Hiperplasia Endometrial , Neoplasias do Endométrio , Módulo de Elasticidade , Hiperplasia Endometrial/diagnóstico por imagem , Neoplasias do Endométrio/diagnóstico por imagem , Feminino , Humanos , Fatores de Risco
4.
Chaos ; 31(8): 083107, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34470251

RESUMO

The firing patterns of each bursting neuron are different because of the heterogeneity, which may be derived from the different parameters or external drives of the same kind of neurons, or even neurons with different functions. In this paper, the different electromagnetic effects produced by two fractional-order memristive (FOM) Hindmarsh-Rose (HR) neuron models are selected for characterizing different firing patterns of heterogeneous neurons. Meanwhile, a fractional-order memristor-coupled heterogeneous memristive HR neural network is constructed via coupling these two heterogeneous FOM HR neuron models, which has not been reported in the adjacent neuron models with memristor coupling. With the study of initial-depending bifurcation behaviors of the system, it is found that the system exhibits abundant hidden firing patterns, such as periods with different topologies, quasiperiodic firings, chaos with different topologies, and even hyperchaotic firings. Particularly, the hidden hyperchaotic firings are perfectly detected by two-dimensional Lyapunov stability graphs in the two-parameter space. Meanwhile, the hidden coexisting firing patterns of the system are excited from two scattered attraction domains, which can be confirmed from the local attraction basins. Furthermore, the color image encryption based on the system and the DNA approach owns great keyspace and a good encryption effect. Finally, the digital implementations based on Advanced RISC Machine are in good coincidence with numerical simulations.


Assuntos
Modelos Neurológicos , Redes Neurais de Computação , Análise por Conglomerados , Neurônios
5.
Gynecol Obstet Invest ; 77(1): 45-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24335000

RESUMO

BACKGROUND/AIMS: Adiponectin receptor 1 (ADIPOR1) is an identified receptor for adiponectin, an adipocytokine with anti-inflammatory and insulin-sensitizing properties. The ADIPOR1 gene is a potential candidate gene in polycystic ovary syndrome (PCOS). The aim of this study is to assess the association between single-nucleotide polymorphism (SNP) rs1539355 in the ADIPOR1 gene and PCOS in Chinese women. METHODS: 302 patients with PCOS and 312 healthy controls were included in this study. The ADIPOR1 genotype distribution was detected using the polymerase chain reaction melting temperature shift method. RESULTS: The genotypic distributions of SNP rs1539355 did not differ in patients with PCOS compared to controls. However, the frequency of the G allele in the PCOS group was significantly higher than that in the control group (p = 0.037). Patients with the AG or GG genotype had a higher homeostasis model assessment for insulin resistance (HOMA-IR) (p < 0.05) compared to patients with the AA genotype. The fasting insulin levels in subjects with the GG genotype were significantly higher than those in patients with the AA genotype (p < 0.05). CONCLUSION: SNP rs1539355 in the ADIPOR1 gene is associated with insulin resistance in Chinese PCOS patients.


Assuntos
Resistência à Insulina/genética , Síndrome do Ovário Policístico/genética , Receptores de Adiponectina/genética , Alelos , Povo Asiático/genética , Distribuição de Qui-Quadrado , DNA/química , DNA/genética , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
6.
Sci Rep ; 14(1): 21647, 2024 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289423

RESUMO

Limited data on the correlation between the perineal body (PB) and stress urinary incontinence (SUI) are available. The objectives of this study were to quantify the PB using shear wave elastography (SWE) technology with a high-frequency linear array probe to evaluate the relationship between the properties of PB and stress urinary incontinence (SUI). This study included 64 women with SUI and 70 female control participants. The length, height, perimeter, and area of PB in all participants were calculated using transperineal ultrasound, and the elasticity of PB was assessed by SWE at rest and during the maximal Valsalva maneuver, respectively. In addition, the comparison of PB parameters between the patients with SUI and the healthy participants was conducted. The transperineal ultrasound and SWE examination was performed in 134 participants, and the elastic modulus values were significantly increased from participants at rest to those during the maximal Valsalva maneuver in all participants (Emax: 35.59 versus 53.13 kPa, P < 0.001; and Emean: 26.97 versus 40.25 kPa, P < 0.001). Emax and Emean of PB exhibited significant differences during the maximal Valsalva maneuver between the SUI group and the control group (47.73 versus 58.06 kPa, P < 0.001; and 35.78 versus 44.33 kPa, P < 0.001) and had a negative correlation with SUI. The BMI and PB height during the maximal Valsalva maneuver in the SUI group were found to be significantly higher than that in healthy volunteers. Emax and Emean of PB negatively correlated with BMI during the maximal Valsalva maneuver (r = -0.277, P = 0.001 and r = -0.211, P = 0.014). ROC curve analysis demonstrated that PB perimeter of less than 12.68mm was strongly associated with SUI during the maximal Valsalva maneuver, and an Emax of less than 55.76 kPa had a 100% specificity in predicting SUI. SWE can quantify the elasticity of PB, identifying a significant difference between participants at rest and during Valsalva maneuver. In addition, the stiffness of the PB was significantly lower in women with SUI than in healthy women, which may provide a noninvasive clinical practice in SUI prediction.


Assuntos
Técnicas de Imagem por Elasticidade , Períneo , Incontinência Urinária por Estresse , Humanos , Feminino , Técnicas de Imagem por Elasticidade/métodos , Incontinência Urinária por Estresse/fisiopatologia , Incontinência Urinária por Estresse/diagnóstico por imagem , Pessoa de Meia-Idade , Períneo/diagnóstico por imagem , Períneo/fisiopatologia , Adulto , Manobra de Valsalva , Módulo de Elasticidade , Estudos de Casos e Controles , Idoso
7.
Ginekol Pol ; 94(10): 799-806, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36929789

RESUMO

OBJECTIVES: To evaluate the diagnostic value of Ovarian-adnexal Reporting and Data System (O-RADS), and to compare it with Assessment of Different NEoplasias in the adnexa (ADNEX) model, Subjective Assessment (SA), and Risk of Malignancy Index (RMI) in differentiating benign and malignant adnexal masses (AMs). MATERIAL AND METHODS: Ultrasound characteristics of 445 patients included in the study were retrospectively analyzed and evaluated using diagnostic models. The diagnostic performances of ultrasound diagnostic models were measured by assessing, receiver-operating characteristic curves, sensitivities, positive predictive values, positive likelihood ratios, specificities, negative predictive values, and negative likelihood ratios. Kappa values were used to evaluate inter-reviewer agreement (IRA). RESULTS: Of the 445 AMs, 265 were benign and 180 were malignant. The area under the curve (AUC) of O-RADS (0.941), ADNEX model (0.925), and SA (0.931) were higher than RMI (0.815) (all p < 0.05). The sensitivity of O-RADS (93.3%), ADNEX model (94.4%), and SA (96.1%) were higher than RMI (70.6%) (p > 0.05), and there was no statistical significance among them (p > 0.05). The specificity of O-RADS, ADNEX model, SA, and RMI was 90.2%, 90.6%, 90.2%, and 92.5%, respectively, with no statistical significance (p > 0.05). All four ultrasound diagnostic methods showed better IRA. CONCLUSIONS: O-RADS, ADNEX model and SA have better diagnostic value in differentiating benign and malignant AMs than RMI.


Assuntos
Doenças dos Anexos , Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/patologia , Estudos Retrospectivos , Doenças dos Anexos/diagnóstico , Anexos Uterinos/patologia , Ultrassonografia , Sensibilidade e Especificidade
8.
J Ultrasound Med ; 30(6): 765-71, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21632990

RESUMO

OBJECTIVES: The aims of this study were to investigate the correlation between osteopontin expression and microcalcification seen on sonograms of human papillary thyroid carcinoma and to explore the mechanism of microcalcification in these tumors. METHODS: Real-time reverse transcription-polymerase chain reaction and immunohistochemistry were used to determine expression levels and locations of osteopontin in 56 pathologically verified papillary thyroid carcinoma nodules. Osteopontin expression correlated with microcalcification and other sonographic signs recorded preoperatively. RESULTS: Osteopontin expression in the papillary thyroid carcinoma group was significantly enhanced compared with the control group for both messenger RNA and protein levels (P < .05). Osteopontin expression was significantly related to microcalcification and lymph node metastasis (P < .05), as shown on sonography. CONCLUSIONS: Our results suggest a possible role for osteopontin in the formation of microcalcification in papillary thyroid carcinoma; the sonographic signs can reflect the pathologic and biological behavior of these tumors.


Assuntos
Calcinose/diagnóstico por imagem , Calcinose/metabolismo , Carcinoma Papilar/diagnóstico por imagem , Carcinoma Papilar/metabolismo , Osteopontina/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/metabolismo , Adolescente , Adulto , Idoso , Calcinose/complicações , Carcinoma Papilar/complicações , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteopontina/genética , RNA/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto , Ultrassonografia/métodos , Adulto Jovem
9.
Ultrasound Med Biol ; 46(9): 2207-2214, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32565129

RESUMO

This study aimed to explore the feasibility of transperineal virtual touch tissue quantification (VTQ) for predicting the outcome of labor induction. A total of 80 nulliparous pregnant women were included. Before labor induction, cervical length was measured by B-mode sonography, cervical stiffness was measured by VTQ, and Bishop score was assessed by vaginal examination. Subsequently, labor was induced using standard oxytocin infusion in all patients. Delivery within 24 hours after labor induction was classified as spontaneous delivery; otherwise, cesarean delivery was performed. Out of 80 participants, 48 (60%) delivered vaginally and 32 (40%) underwent cesarean delivery. The cervical length was significantly longer and the shear wave velocity (SWV) was greater in the cesarean delivery group than in the vaginal delivery group (p = 0.004 and p < 0.000, respectively). Logistic regression analysis indicated that only the mean SWV had independent predictive value for the outcome of labor induction (p = 0.011). The best diagnostic cut-off point of the mean SWV was 1.23 m/s, with a sensitivity of 93.8% and a specificity of 89.6%. Transperineal VTQ technique could predict the outcome of labor induction using oxytocin.


Assuntos
Colo do Útero/diagnóstico por imagem , Trabalho de Parto Induzido , Ultrassonografia Pré-Natal/métodos , Adulto , Feminino , Humanos , Períneo , Valor Preditivo dos Testes , Gravidez , Resultado do Tratamento
10.
Clinics (Sao Paulo) ; 75: e1691, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33146349

RESUMO

OBJECTIVE: Imaging diagnosis of cervical lymphadenopathy has conventionally used ultrasonography. Shear wave elastography (SWE) is a recent ultrasound technological advancement that has shown promise in the important medical problem of differentiating between benign and malignant cervical lymph nodes based on quantitative measurements of elasticity modulus. However, widely varying elasticity modulus metrics and regions-of-interest (ROIs) were used in existing studies, leading to inconsistent findings and results that are hard to compare with each other. METHODS: Using a large dataset of 264 cervical lymph nodes from 200 patients, we designed a study comparing three elasticity modulus metrics (Emax, Emean, and standard deviation-SD) with three different ROIs to evaluate the effect of such selections. The metric values were compared between the benign and malignant node groups. The different ROI and metric selections were also compared through receiver operating characteristics curve analysis. RESULTS: For all ROIs, all metric values were significantly different between the two groups, indicting their diagnostic potential. This was confirmed by the ≥0.80 area under the curve (AUC) values achieved with these metrics. Different ROIs had no effect on Emax, whereas all ROIs achieved high performance at 0.88 AUC. For Emean, the smallest ROI focusing on the area of the highest elasticity achieved the best diagnostic performance. In contrast, the larger ROIs achieved higher performances for SD. CONCLUSIONS: This study illustrated the effect of elasticity modulus and ROI selection on the diagnostic performance of SWE on cervical lymphadenopathy. These new findings help guide relevant future studies and clinical applications of this important quantitative imaging modality.


Assuntos
Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Diagnóstico Diferencial , Módulo de Elasticidade , Humanos , Linfonodos/diagnóstico por imagem , Pescoço/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia
11.
Gynecol Obstet Invest ; 68(3): 171-3, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19648752

RESUMO

OBJECTIVE: The aim of the study was to determine the association between three single nucleotide polymorphism (SNP) variants (rs35368790, rs35069869 and rs684846) of the MCF2 cell line-derived transforming sequence-like 2 (MCF2L2) gene and polycystic ovary syndrome (PCOS) in PCOS family trios. METHODS: Genotyping was done by TaqMan assay that incorporates minor groove-binding probe technology for allelic discrimination. One hundred and fifty-two unrelated PCOS probands and their biological parents were recruited. All subjects were of Han Chinese origin and from Shandong Province. RESULTS: The transmission disequilibrium test (TDT) for allelic association demonstrated that a weak association was detected in SNP rs35368790 with p = 0.008. However, we found no significant transmission distortion of the other two SNPs (rs35069869, chi(2) = 3.645, p = 0.056; rs684846, chi(2) = 1.429, p = 0.232, respectively). CONCLUSIONS: These results suggest that the genetic polymorphisms within MCF2L2 are likely to confer an increased susceptibility to PCOS in the Chinese population. Our present data may provide a basis for further studies of the role of the MCF2L2 gene in the etiology of PCOS.


Assuntos
Síndrome do Ovário Policístico/genética , Proteínas de Transporte Vesicular/genética , Povo Asiático/genética , DNA/química , DNA/genética , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
12.
Clinics ; Clinics;75: e1691, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1133437

RESUMO

OBJECTIVE: Imaging diagnosis of cervical lymphadenopathy has conventionally used ultrasonography. Shear wave elastography (SWE) is a recent ultrasound technological advancement that has shown promise in the important medical problem of differentiating between benign and malignant cervical lymph nodes based on quantitative measurements of elasticity modulus. However, widely varying elasticity modulus metrics and regions-of-interest (ROIs) were used in existing studies, leading to inconsistent findings and results that are hard to compare with each other. METHODS: Using a large dataset of 264 cervical lymph nodes from 200 patients, we designed a study comparing three elasticity modulus metrics (Emax, Emean, and standard deviation-SD) with three different ROIs to evaluate the effect of such selections. The metric values were compared between the benign and malignant node groups. The different ROI and metric selections were also compared through receiver operating characteristics curve analysis. RESULTS: For all ROIs, all metric values were significantly different between the two groups, indicting their diagnostic potential. This was confirmed by the ≥0.80 area under the curve (AUC) values achieved with these metrics. Different ROIs had no effect on Emax, whereas all ROIs achieved high performance at 0.88 AUC. For Emean, the smallest ROI focusing on the area of the highest elasticity achieved the best diagnostic performance. In contrast, the larger ROIs achieved higher performances for SD. CONCLUSIONS: This study illustrated the effect of elasticity modulus and ROI selection on the diagnostic performance of SWE on cervical lymphadenopathy. These new findings help guide relevant future studies and clinical applications of this important quantitative imaging modality.


Assuntos
Humanos , Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Reprodutibilidade dos Testes , Ultrassonografia , Sensibilidade e Especificidade , Diagnóstico Diferencial , Módulo de Elasticidade , Linfonodos/diagnóstico por imagem , Pescoço/diagnóstico por imagem
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