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1.
ACS Nano ; 18(20): 13141-13149, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38718265

RESUMO

Electrocatalytic reduction of NO2- to NH3 (NO2RR) offers an effective method for alleviating NO2- pollution and generating valuable NH3. Herein, a p-block single-atom alloy, namely, isolated Sb alloyed in a Cu substrate (Sb1Cu), is explored as a durable and high-current-density NO2RR catalyst. As revealed by the theoretical calculations and operando spectroscopic measurements, we demonstrate that Sb1 incorporation can not only hamper the competing hydrogen evolution reaction but also optimize the d-band center of Sb1Cu and intermediate adsorption energies to boost the protonation energetics of NO2--to-NH3 conversion. Consequently, Sb1Cu integrated in a flow cell achieves an outstanding NH3 yield rate of 2529.4 µmol h-1 cm-2 and FENH3 of 95.9% at a high current density of 424.2 mA cm-2, as well as a high durability for 100 h of electrolysis.

2.
Dalton Trans ; 53(8): 3470-3475, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38323778

RESUMO

Electrocatalytic NO2--to-NH3 reduction (NO2RR) has emerged as an intriguing route for simultaneous mitigation of harmful nitrites and production of valuable NH3. Herein, we design for the first time undercoordinated Cu nanowires (u-Cu) as an efficient and selective NO2RR electrocatalyst, delivering the maximum NO2--to-NH3 faradaic efficiency of 94.7% and an ammonia production rate of 494.5 µmol h-1 cm-2 at -0.7 V vs. RHE. Theoretical calculations reveal that the created undercoordinated Cu sites on u-Cu can enhance NO2- adsorption, boost NO2--to-NH3 energetics and restrict competitive hydrogen evolution, thereby enabling the active and selective NO2RR.

4.
Health Sci Rep ; 6(7): e1412, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37441130

RESUMO

Background and Aims: Shear wave elastography is a potential method for evaluating peripheral neuropathy, but lacking reference values. The aim of this study was to measure tibial nerve stiffness in healthy individuals using shear wave elastography and to investigate the influencing factors of tibial nerve stiffness. Methods: Shear wave elastography of bilateral tibial nerves was performed in 50 healthy individuals 4 cm proximal to the medial malleolus. Mean shear modulus data of tibial nerves were obtained and recorded. Intra- and interobserver agreement were assessed using intraclass correlation coefficients. Differences among groups (grouped by laterality, sex, age, and body mass index) were analyzed with independent-samples t-tests and paired t-tests. Effect size (Cohen's d) was also calculated. Results: The intra-and interobserver agreement were moderate (intraclass correlation coefficient, 0.700-0.747) for all participants, and was poor (intraclass correlation coefficient, 0.265-0.088) in very thin people (body mass index <18.5 kg/m2). The shear wave elastography measurements of the tibial nerve did not show a significant difference between legs, sexes, or different age groups. Higher values of tibial nerve stiffness were found in thinner participants. Conclusions: Shear wave elastography is a method to evaluate the stiffness of peripheral nerves. The measurement results were likely influenced by body mass index of the participants.

5.
JCO Precis Oncol ; 7: e2200337, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36652665

RESUMO

PURPOSE: Pathologic complete response (pCR) rates of patients with triple-negative breast cancer who were administered docetaxel plus carboplatin were significantly higher than those of patients administered epirubicin/cyclophosphamide followed by docetaxel in the neoadjuvant NeoCART trial. Here, we performed a preplanned secondary analysis of the homologous recombination deficiency (HRD) score as a predictor of the pCR in patients with triple-negative breast cancer from the NeoCART cohort. METHODS: Pretherapeutic tumor tissues were assessed retrospectively by DNA extraction and sequencing. BRCA1/2 mutations were evaluated in both somatic and germline forms. HRD scores were calculated from genome-wide allele-specific copy number results and comprised telomeric allelic imbalance, loss of heterozygosity, and large-scale state transitions. High HRD scores were defined as ≥ 38, and HRD was defined as either a high HRD score or a deleterious BRCA1/2 mutation. RESULTS: HRD testing was completed for 43 (79.6%) of 54 NeoCART cohort patients. Thirty of 43 (69.8%) tumors had high HRD scores, and eight patients had BRCA-mutated tumors. No significant association between BRCA1/2 mutation status and pCR was observed either in the general population or in the two treatment arms. Docetaxel plus carboplatin group patients who achieved pCR had higher HRD scores than non-pCR patients, and this difference approached significance (61.69 ± 24.26 v 39.44 ± 22.83, P = .061). No significant correlations between HRD scores and pCR (61.29 ± 24.02 v 53.21 ± 24.31, P = .480) or residual cancer burden 0/1 (62.50 ± 22.50 v 51.85 ± 24.74, P = .324) were observed in the epirubicin/cyclophosphamide followed by docetaxel group. CONCLUSION: HRD is a potential predictive biomarker for clinical benefit from neoadjuvant carboplatin-based chemotherapy and provides a possibility for screening the optimum chemotherapy backbone to combine with immunotherapy.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Carboplatina/uso terapêutico , Mutação , Epirubicina/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Docetaxel/uso terapêutico , Terapia Neoadjuvante/métodos , Estudos Retrospectivos , Proteína BRCA1/genética , Recombinação Homóloga/genética , Ciclofosfamida/uso terapêutico
6.
Eur J Radiol ; 146: 110066, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34902668

RESUMO

PURPOSE: In this study we aimed to leverage deep learning to develop a computer aided diagnosis (CAD) system toward helping radiologists in the diagnosis of SARS-CoV-2 virus syndrome on Lung ultrasonography (LUS). METHOD: A CAD system is developed based on a transfer learning of a residual network (ResNet) to extract features on LUS and help radiologists to distinguish SARS-CoV-2 virus syndrome from healthy and non-SARS-CoV-2 pneumonia. A publicly available LUS dataset for SARS-CoV-2 virus syndrome consisting of 3909 images has been employed. Six radiologists with different experiences participated in the experiment. A comprehensive LUS data set was constructed and employed to train and verify the proposed method. Several metrics such as accuracy, recall, precision, and F1-score, are used to evaluate the performance of the proposed CAD approach. The performances of the radiologists with and without the help of CAD are also evaluated quantitively. The p-values of the t-test shows that with the help of the CAD system, both junior and senior radiologists significantly improve their diagnosis performance on both balanced and unbalanced datasets. RESULTS: Experimental results indicate the proposed CAD approach and the machine features from it can significantly improve the radiologists' performance in the SARS-CoV-2 virus syndrome diagnosis. With the help of the proposed CAD system, the junior and senior radiologists achieved F1-score values of 91.33% and 95.79% on balanced dataset and 94.20% and 96.43% on unbalanced dataset. The proposed approach is verified on an independent test dataset and reports promising performance. CONCLUSIONS: The proposed CAD system reports promising performance in facilitating radiologists' diagnosis SARS-CoV-2 virus syndrome and might assist the development of a fast, accessible screening method for pulmonary diseases.


Assuntos
COVID-19 , SARS-CoV-2 , Computadores , Diagnóstico por Computador , Humanos , Ultrassonografia
7.
Front Oncol ; 11: 724656, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926246

RESUMO

OBJECTIVES: Mucinous breast cancer (MBC), particularly pure MBC (pMBC), often tend to be confused with fibroadenoma (FA) due to their similar images and firm masses, so some MBC cases are misdiagnosed to be FA, which may cause poor prognosis. We analyzed the ultrasonic features and aimed to identify the ability of multilayer perceptron (MLP) to classify early MBC and its subtypes and FA. MATERIALS AND METHODS: The study consisted of 193 patients diagnosed with pMBC, mMBC, or FA. The area under curve (AUC) was calculated to assess the effectiveness of age and 10 ultrasound features in differentiating MBC from FA. We used the pairwise comparison to examine the differences among MBC subtypes (pure and mixed types) and FA. We utilized the MLP to differentiate MBC and its subtypes from FA. RESULTS: The nine features with AUCs over 0.5 were as follows: age, echo pattern, shape, orientation, margin, echo rim, vascularity distribution, vascularity grade, and tumor size. In subtype analysis, the significant differences were obtained in 10 variables (p-value range, 0.000-0.037) among pMBC, mMBC, and FA, except posterior feature. Through MLP, the AUCs of predicting MBC and FA were both 0.919; the AUCs of predicting pMBC, mMBC, and FA were 0.875, 0.767, and 0.927, respectively. CONCLUSION: Our study found that the MLP models based on ultrasonic characteristics and age can well distinguish MBC and its subtypes from FA. It may provide a critical insight into MBC preoperative clinical management.

8.
Front Endocrinol (Lausanne) ; 12: 734900, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557165

RESUMO

Background: Many clinicians are facing the dilemma about whether they should apply the active surveillance (AS) strategy for managing Clinically Node-negative (cN0) PTMC patients in daily clinical practice. This research plans to construct a dynamic nomogram based on network, connected with ultrasound characteristics and clinical data, to predict the risk of central lymph node metastasis (CLNM) in cN0 PTMC patients before surgery. Methods: A retrospective analysis of 659 patients with cN0 PTMC who had underwent thyroid surgery and central compartment neck dissection. Patients were randomly (2:1) divided into the development cohort (439 patients) and validation cohort (220 patients). The group least absolute shrinkage and selection operator (Group Lasso) regression method was used to select the ultrasonic features for CLNM prediction in the development cohort. These features and clinical data were screened by the multivariable regression analysis, and the CLNM prediction model and web-based calculator were established. Receiver operating characteristic, calibration curve, Clinical impact curve and decision curve analysis (DCA) were used to weigh the performance of the prediction model in the validation set. Results: Multivariable regression analysis showed that age, tumor size, multifocality, the number of contact surface, and real-time elastography were risk factors that could predict CLNM. The area under the curve of the prediction model in the development and validation sets were 0.78 and 0.77, respectively, with good discrimination and calibration. A web-based dynamic calculator was built. DCA proved that the prediction model had excellent net benefits and clinical practicability. Conclusions: The web-based dynamic nomogram incorporating US and clinical features was able to forecast the risk of preoperative CLNM in cN0 PTMC patients, and has good predictive performance. As a new observational indicator, NCS can provide additional predictive information.


Assuntos
Carcinoma Papilar/diagnóstico , Carcinoma Papilar/cirurgia , Técnicas de Apoio para a Decisão , Nomogramas , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/cirurgia , Adolescente , Adulto , Idoso , Carcinoma Papilar/patologia , Estudos de Coortes , Feminino , Humanos , Internet , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Período Pré-Operatório , Prognóstico , Análise de Regressão , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia , Ultrassonografia , Conduta Expectante/métodos , Adulto Jovem
9.
Arch Gynecol Obstet ; 294(2): 285-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26861464

RESUMO

OBJECTIVE: To identify and characterize changes in the pelvic floor and pubic bone, using magnetic resonance imaging, in primiparous women with normal vaginal delivery, in comparison with nulliparous women. METHODS: Pelvic MR images from ten primiparous women, 6-7 weeks after normal vaginal delivery, and ten nulliparous women were obtained from January to April 2014. The selected women were scanned using a multiplanar T2FRFSE sequence and T2fsFRFSE sequence. Changes in the pelvic floor and pubic bone in primiparous women, including tears of the levator ani fibers, pubic bone edema, and fractures, were assessed on the MR images in comparison with images from normal nulliparous women. Injury to the levator ani was evaluated and scored. The incidence, location and the extent of injury to the levator ani and pubic bone were characterized further. RESULTS: Eight out of ten primiparous women had imaging abnormalities after normal vaginal delivery. Three women had unilateral tears of the pubococcygeus, in which the defect in the muscle was located at or near its origin at the pubic bone, and one had a pubococcygeus tear accompanied by bilateral spilling of the vagina. Four women had partial tears of the iliococcygeus: one was a bilateral tear, and three were unilateral. None had a tear of the coccygeus. Eight women had pubic bone marrow edema; one was accompanied by a pubic bone fracture line. None of the nulliparous women had any abnormality of the pelvic floor and pubic bone. CONCLUSION: Abnormalities of the pelvic floor and pubic bone were observed in primiparous women but not in nulliparous women. In primiparous women, most levator ani muscle tears are at or near the point of origin, and pubococcygeus injuries are usually accompanied by pubic bone marrow edema.


Assuntos
Parto Obstétrico , Imageamento por Ressonância Magnética/métodos , Diafragma da Pelve/diagnóstico por imagem , Osso Púbico/diagnóstico por imagem , Adulto , China , Edema/diagnóstico por imagem , Feminino , Fraturas Ósseas/diagnóstico por imagem , Humanos , Lacerações , Paridade , Parto , Diafragma da Pelve/lesões , Gravidez , Osso Púbico/lesões , Vagina/lesões
10.
Zhonghua Fu Chan Ke Za Zhi ; 50(9): 668-72, 2015 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-26675393

RESUMO

OBJECTIVE: To evaluate morphological structure of uterosacral ligament (USL) and cardinal ligament (CL) in patients with severe pelvic organ prolapse (POP) by MRI technology, and to analysis and discuss its clinical significance. METHODS: From November 2013 to February 2014 in Peking University People's Hospital, 26 elderly patients with III-IV degree of POP were selected as the POP group and 18 healthy elderly volunteers were selected as the control group during the same period. Pelvic MRI examination were performed in the two groups. The morphological characteristics of left and right side of the uterosacral-cardinal ligament on MRI and the attachment site of the starting and ending points between two group were described and compared. RESULTS: In POP group, 25 cases of left USL starting point were located in the sacrospinous ligament/coccygeal muscle complex [58% (15/26)] or coccygeal muscle [38% (10/26)], ending point were located in the cervix and vagina [58% (15/26)] or cervix [38% (10/26)]; 24 cases of right USL starting point were located in the sacrospinous ligament/coccygeal muscle complex [31% (8/26)] or coccygeal muscle [62% (16/26)], 26 cases of right USL ending point were located in the cervix and vagina [62% (16/26)] or cervix [38% (10/26)]; the left and right CL in the POP group and the control group were both from the sacroiliac joint at the top of the greater sciatic foramen from the ipsilateral pelvic side wall; 1 case (4%, 1/26) of left CL in the POP group completely connected to the bladder, 10 cases (38%, 10/26) partly connected to the bladder; 14 cases (54%, 14/26) of right CL partly connected to the bladder, the rest ending points of left and right CL were located in cervix and (or) vagina. In the control group, 17 cases of left USL starting point were located in the sacrospinous ligament/coccygeal muscle complex (10/18) or coccygeal muscle (7/18), ending point were located in the cervix and vagina (12/18) or cervix (6/18); 18 cases of right USL starting point were located in the sacrospinous ligament/coccygeal muscle complex (10/18) or coccygeal muscle (8/18), ending point were located in the cervix and vagina (13/18) or cervix (5/18); 8 cases (8/18) of left CL partly connected to the bladder; 15 cases (15/18) of right CL partly connected to the bladder, the rest ending points of left and right CL were located in cervix and (or) vagina. There was no significant difference between the two groups on the starting and ending points (P > 0.05). CONCLUSIONS: The observation of MRI could be consistent with the clinical anatomy on the starting and ending points, direction of travel in the uterosacral-cardinal ligament. The starting and ending points of the left and right side USL and the ending points of the left and right side CL are not completely symmetrical, the variation degree is large, some CL could be completely or partly inserted to the bladder.


Assuntos
Colo do Útero/anatomia & histologia , Ligamentos/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Prolapso de Órgão Pélvico/patologia , Vagina/anatomia & histologia , Adulto , Idoso , Colo do Útero/patologia , China , Feminino , Humanos , Ísquio/anatomia & histologia , Ligamentos/patologia , Diafragma da Pelve , Peritônio , Sacro/anatomia & histologia , Bexiga Urinária , Útero/anatomia & histologia , Vagina/patologia
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