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1.
Small ; : e2401103, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709231

RESUMO

The unsaturated amides are traditionally synthesized by acylation of carboxylic acids or hydration of nitrile compounds but are rarely investigated by hydroaminocarbonylation of alkynes using heterogeneous single-metal-site catalysts (HSMSCs). Herein, single-Pd-site catalysts supported on N-doping carbon (NC) with different nitrogen dimensions inherited from corresponding metal-organic-framework precursors are successfully synthesized. 2D NC-supported single-Pd-site (Pd1/NC-2D) exhibited the best performance with near 100% selectivity and 76% yield of acrylamide for acetylene hydroaminocarbonylation with better stability, superior to those of Pd1/NC-3D, single-metal-site/nanoparticle coexisting catalyst, and nanoparticle catalyst. The coordination environment and molecular evolution of the single-Pd-site during the process of acetylene hydroaminocarbonylation on Pd1/NC-2D are detailly illuminated by various characterizations and density functional theoretical calculations (DFT). DFT also showed the energy barrier of rate-determining step on Pd1/NC-2D is lower than that of Pd1/NC-3D. Furthermore, Pd1/NC-2D catalyst illustrated the general applicability of the hydroaminocarbonylation for various alkynes.

2.
Nat Commun ; 15(1): 2555, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519506

RESUMO

The direct conversion of low alkane such as ethane into high-value-added chemicals has remained a great challenge since the development of natural gas utilization. Herein, we achieve an efficient one-step conversion of ethane to C2 oxygenates on a Rh1/AC-SNI catalyst under a mild condition, which delivers a turnover frequency as high as 158.5 h-1. 18O isotope-GC-MS shows that the formation of ethanol and acetaldehyde follows two distinct pathways, where oxygen and water directly participate in the formation of ethanol and acetaldehyde, respectively. In situ formed intermediate species of oxygen radicals, hydroxyl radicals, vinyl groups, and ethyl groups are captured by laser desorption ionization/time of flight mass spectrometer. Density functional theory calculation shows that the activation barrier of the rate-determining step for acetaldehyde formation is much lower than that of ethanol, leading to the higher selectivity of acetaldehyde in all the products.

3.
BMC Cancer ; 24(1): 23, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166768

RESUMO

AIM: Pathologists are currently supposed to be aware of both domestic and international guidelines for breast cancer diagnosis, but it is unclear how successfully these guidelines have been integrated into routine clinical practice in China. Thus, this national proficiency testing (PT) scheme for breast pathology was set up to conduct a baseline assessment of the diagnostic capability of pathologists in China. METHODS: This national PT plan is designed and implemented according to the "Conformity assessment-General requirements for proficiency testing" (GB/T27043-2012/ISO/IEC 17043:2010). Five cases of breast cancer with six key items, including histologic type, grade, ER, PR, HER2, and Ki67, were selected for testing among 96 participants. The final PT results were published on the website of the National Quality Control Center for Cancer ( http://117.133.40.88:3927/cn/col22/362 ). RESULTS: Our study demonstrated that the median PT score was 89.5 (54-100). Two institutions with scores < 67 were deemed unacceptable. The accuracy of histologic type, ER, PR, HER2, and Ki67 was satisfactory (all > 86%). However, the histologic grade showed low accuracy (74.0%). The unacceptable results mainly included incorrect evaluation of histologic grade (36.7%), inaccurate evaluation of ER/PR/HER2/Ki67 (28.2%), incorrect identification of C-AD as IBC-NST (15.7%), inappropriate use of 1+/2+/3+ rather than staining percentage for ER/PR (6.1%), misclassification of ER/PR < 1% weak expression as positive staining (1.4%), and no evaluation of histologic grade in ILC, MC, and IMC (5.8%). CONCLUSIONS: our nationwide PT program exhibited a satisfactory baseline assessment of the diagnostic capability of pathologists in China. More importantly, we identify some areas for further improvement.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Antígeno Ki-67/metabolismo , Receptor ErbB-2/metabolismo , Imuno-Histoquímica , Receptores de Estrogênio/metabolismo , Ensaio de Proficiência Laboratorial , Receptores de Progesterona/metabolismo , Biomarcadores Tumorais/metabolismo
4.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38044477

RESUMO

Volitional eyes closing would shift brain's information processing modes from the "exteroceptive" to "interoceptive" state. This transition induced by the eyes closing is underpinned by a large-scale reconfiguration of brain network, which is still not fully comprehended. Here, we investigated the eyes-closing-relevant network reconfiguration by examining the functional integration among intrinsic modules. Our investigation utilized a publicly available dataset with 48 subjects being scanned in both eyes closed and eyes open conditions. It was found that the modular integration was significantly enhanced during the eyes closing, including lower modularity index, higher participation coefficient, less provincial hubs, and more connector hubs. Moreover, the eyes-closing-enhanced integration was particularly noticeable in the hubs of network, mainly located in the default-mode network. Finally, the hub-dominant modular enhancement was positively correlated to the eyes-closing-reduced entropy of BOLD signal, suggesting a close connection to the diminished consciousness of individuals. Collectively, our findings strongly suggested that the enhanced modular integration with substantially reorganized hubs characterized the large-scale cortical underpinning of the volitional eyes closing.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Encéfalo/diagnóstico por imagem , Olho , Mapeamento Encefálico , Cognição , Rede Nervosa/diagnóstico por imagem
5.
Small ; 19(52): e2305666, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37635104

RESUMO

Tuning the coordination environment of the metal center in metal-nitrogen-carbon (M-N-C) single-atom catalysts via heteroatom-doping (oxygen, phosphorus, sulfur, etc.) is effective for promoting electrocatalytic CO2 reduction reaction (CO2 RR). However, few studies are investigated establishing efficient CO2 reduction by introducing boron (B) atoms to regulate the M-N-C structure. Herein, a B-C3 N4 self-sacrifice strategy is developed to synthesize B, N co-coordinated Ni single atom catalyst (Ni-BNC). X-ray absorption spectroscopy and high-angle annular dark field scanning transmission electron microscopy confirm the structure (Ni-N3 B/C). The Ni-BNC catalyst presents a maximum CO Faradaic efficiency (FECO ) of 98.8% and a large CO current density (jCO ) of -62.9 mA cm-2 at -0.75 and -1.05 V versus reversible hydrogen electrode, respectively. Furthermore, FECO could be maintained above 95% in a wide range of potential windows from -0.65 to -1.05 V. In situ experiments and density functional theory calculations demonstrate the Ni-BNC catalyst with B atoms coordinated to the central Ni atoms could significantly reduce the energy barrier for the conversion of *CO2 to *COOH, leading to excellent CO2 RR performance.

6.
Small ; 19(52): e2304423, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37649188

RESUMO

Heteroatom-doping is an effective method for modifying the geometric symmetry of metal-nitrogen-carbon (M-N-C) single-atom catalysts and thereby tuning the electronic structure. Up to now, most of the current reports have concentrated on introducing heteroatoms into the highly symmetrical M-N4 structure. The coordination-unsaturated M-N2 structure is more sterically favorable for the insertion of alien atoms to optimize the electronic structure. Herein, a Ni-N2 catalyst with out-of-plane coordinated chlorine (Cl) atoms (Ni-N2 Cl/C) is successfully constructed on chlorine-functionalized carbon supports (C-Cl) for an efficient carbon dioxide reduction reaction (CO2 RR). Density functional theory calculations demonstrate that the prepared Ni-N2 Cl/C catalyst exhibits a higher capability in balancing COOH* formation and CO* desorption. In addition, in situ Raman spectra confirm that the lower CO binding energy on the Ni-N2 Cl/C facilitates CO escape, leading to excellent CO2 RR performance. A high CO Faradaic efficiency (FECO ) of more than 80% is achieved from -0.6 to -1.2 V versus reversible hydrogen electrode on the Ni-N2 Cl/C and it exhibits negligible FECO and current declination over a 40-h stability test. Furthermore, a high turnover frequency (TOF) value of 15 808 h-1 is obtained, which is more than ten times that of Ni-N2 /C (1476 h-1 ) without coordinated Cl atoms.

7.
Angew Chem Int Ed Engl ; 62(33): e202307570, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37310795

RESUMO

Heterogeneous single-metal-site catalysts usually suffer from poor stability, thereby limiting industrial applications. Dual Pd1 -Ru1 single-atom-sites supported on porous ionic polymers (Pd1 -Ru1 /PIPs) were constructed using a wetness impregnation method. The two isolated metal species in the form of a binuclear complex were immobilized on the cationic framework of PIPs through ionic bonds. Compared to the single Pd- or Ru-site catalyst, the dual single-atom system exhibits higher activity with 98 % acetylene conversion and near 100 % selectivity to dialkoxycarbonylation products, as well as better cycling stability for ten cycles without obvious decay. Based on DFT calculations, it was found that the single-Ru site exhibited a strong CO adsorption energy of -1.6 eV, leading to an increase in the local CO concentration of the catalyst. Notably, the Pd1 -Ru1 /PIPs catalyst had a much lower energy barrier of 2.49 eV compared to 3.87 eV of Pd1 /PIPs for the rate-determining step. The synergetic effect between neighboring single sites Pd1 and Ru1 not only enhanced the overall activity, but also stabilized PdII active sites. The discovery of synergetic effects between single sites can deepen our understanding of single-site catalysts at the molecular level.

8.
Pathol Oncol Res ; 29: 1611204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37378074

RESUMO

Tumor-to-tumor metastasis is a rare phenomenon. Although renal cell carcinoma is the most common recipient tumor, metastatic lobular breast carcinoma to clear cell renal cell carcinoma is even rarer, with only one case reported to date. We present a 66-year-old female patient with an invasive lobular carcinoma history who was admitted to the hospital with a right renal mass. The patient received partial nephrectomy. The final established diagnosis is lobular breast carcinoma metastasizing to clear cell renal cell carcinoma (ccRCC). Thus, although rare, the simultaneous or consecutive find of a renal mass in follow-up should be carefully evaluated, especially in high-risk patients, including women with an advanced breast cancer history, as in this scenario.


Assuntos
Neoplasias da Mama , Carcinoma Lobular , Carcinoma de Células Renais , Neoplasias Renais , Segunda Neoplasia Primária , Humanos , Feminino , Idoso , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Renais/patologia , Carcinoma Lobular/patologia , Neoplasias da Mama/patologia , Neoplasias Renais/patologia
9.
Chronic Dis Transl Med ; 9(1): 29-38, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36926257

RESUMO

Background: The differential diagnosis of mucoepidermoid carcinoma (MEC) from neoplasm undergoing mucinous features brings more pitfalls to pathologists. Combining specific MAML2 gene rearrangement and histological characteristics may be the solution. Methods: Twenty-five tumors with mucinous components were selected for differential diagnosis of MEC. All the cases were detected for MAML2 gene rearrangement. The cases diagnosed as MEC were classified into four variants: classic, oncocytic, Warthin-like, and nonclassified, and they were graded using the Brandwein system. The histological characteristics of non-MECs were summarized for differential diagnosis. Univariate survival analysis was performed on MECs. Results: There were 16 MECs; 62.5% were MAML2 rearranged. For the low-, intermediate-, and high-grade MECs, the rate of rearrangement was 83.3%, 100%, and 28.6%, respectively. Both the oncocytic and Warthin-like MECs were MAML2 rearranged. For the classic and nonclassified MECs without MAML2 rearrangement, non-keratinized squamoid cells and distinctive mucinous cells were essential diagnostic criteria. On survival analysis, all the disease progression occurred in high-grade MECs (p = 0.038). Nine cases were diagnosed as non-MECs: pleomorphic adenoma with mucinous metaplasia showed no ex-capsular involvement; metaplastic Warthin tumor appeared with overt keratinization and residual oncocytic bilayered epithelium; mix squamous cell and glandular papilloma showed an endobronchial papillary growing pattern; adenosquamous carcinoma was accompanied by squamous carcinoma in situ of the overlying mucosa. All the non-MECs were negative for MAML2 rearrangement. Conclusion: The application of combining MAML2 rearrangement and histological characteristics is helpful in the differential diagnosis between MEC and other tumors with mucinous components.

10.
Cancer Biol Med ; 16(3): 587-594, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31565487

RESUMO

OBJECTIVE: To study the sonographic features of the primary site of papillary thyroid microcarcinoma (PTMC) for the prediction of cervical lymph node metastasis during preoperative diagnosis. METHODS: A total of 710 PTMC patients between 2013 and 2016 with a diagnosis of cervical lymph node metastases were reviewed. We analyzed the sonographic features of the PTMC primary site to predict ipsilateral or central lymph node metastases in univariate and multivariate models. The ratio of abutment/perimeter of the PTMC primary site was utilized to evaluate cervical lymph node status. RESULTS: Regarding clinical characteristics, multifocality and extrathyroidal extension were associated with cervical lymph node involvement. In the multivariate regression model, calcification and the abutment/perimeter ratio of lesions were evaluated as independent factors in level VI, ipsilateral or skip cervical lymph node metastases. The cut-off value of the ratio of abutment/perimeter of the PTMC primary site (25%) was significantly correlated with cervical lymph node metastases (P = 0.000). CONCLUSIONS: Independent sonographic features, including lesion size, lesion location, calcification, and the ratio of abutment/perimeter of the primary site, were associated with cervical lymph node metastases in PTMC patients.

11.
Cancer Biol Med ; 15(2): 171-177, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29951341

RESUMO

OBJECTIVE: Extranodal extension in cervical lymph nodes is an important risk factor for the progression and prognosis of papillary thyroid cancer. The purpose of this study was to identify the common and characteristic preoperative ultrasonography features that are associated with the pathologic extranodal extension of metastatic papillary thyroid carcinoma. METHODS: We retrospectively assessed and compared clinicopathologic and ultrasound features between 60 papillary thyroid cancer patients with extranodal extension and 120 control patients with papillary thyroid cancer without extranodal extension. RESULTS: With respect to the pathological N stage and clinicopathologic features, N1b stage papillary thyroid carcinomas were more frequently found in patients who were extranodal extension-positive, in comparison with those who were extranodal extension-negative (78.3% vs. 63.3%, P=0.043). Extranodal extension was detected most frequently in level VI cervical lymph nodes (48.7%). In our univariate analysis of patients with papillary thyroid carcinoma, cervical lymph nodes with extranodal extension showed higher incidences of node matting, microcalcification, cystic area, aspect ratio <2, and larger diameter than those without extranodal extension (all P<0.05). Our multivariate analysis demonstrated that node matting and cystic area were independent risk factors for the presence of extranodal extension [odds ratio (OR): 4.751, 95% confidence interval (CI): 1.212~18.626, P=0.025; OR: 2.707, 95% CI: 1.127~6.502, P=0.026]. CONCLUSIONS: Common ultrasound features may indicate the presence of extranodal extension in patients with metastatic cervical lymph nodes of papillary thyroid carcinoma.

12.
ACS Appl Mater Interfaces ; 10(27): 23112-23121, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29923708

RESUMO

Direct dehydrogenation of isobutane to isobutene has drawn extensive attention for synthesizing various chemicals. The Mo-based catalysts hold promise as an alternative to the toxic CrO x- and scarce Pt-based catalysts. However, the low activity and rapid deactivation of the Mo-based catalysts greatly hinder their practical applications. Herein, we demonstrate a feasible approach toward the development of efficient and non-noble metal dehydrogenation catalysts based on Mo-C T hybrid nanowires calcined at different temperatures. In particular, the optimal Mo-C700 catalyst exhibits isobutane consumption rate of 3.9 mmol g-1 h-1 and isobutene selectivity of 73% with production rate of 2.8 mmol g-1 h-1. The catalyst maintained 90% of its initial activity after 50 h of reaction. Extensive characterizations reveal that such prominent performance is well correlated with the adsorption abilities of isobutane and isobutene and the formation of η-MoC species. In contrast, the generation of ß-Mo2C crystalline phase during long-term reaction causes minor decline in activity. Compared to MoO2 and ß-Mo2C, η-MoC plays a role more likely in suppressing the cracking reaction. This work demonstrates a feasible approach toward the development of efficient and non-noble metal dehydrogenation catalysts.

13.
Int J Clin Oncol ; 22(3): 448-454, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28220335

RESUMO

OBJECTIVE: To explore the significance of ultrasonic features in differential diagnosis of thyroid nodules via combining the thyroid imaging reporting and data system (TI-RADS) and multivariate statistical analysis. METHODS: Patients who received surgical treatment and was diagnosed with single thyroid nodule by postoperative pathology and preoperative ultrasound were enrolled in this study. Multivariate analysis was applied to assess the significant ultrasonic features which correlated with identifying benign or malignance and grading the TI-RADS classification of thyroid nodule. RESULTS: There were significant differences in the nodule size, aspect ratio, internal, echogenicity, boundary, presence or absence of calcifications, calcification type and CDFI between benign and malignant thyroid nodules. Multivariate analysis showed clear-cut distinction both between benign and malignance and among different TI-RADS categories of malignancy nodules. The shape and calcification of the nodule were important factors for distinguish the benign and malignance. Height of the nodule, aspect and calcification was important factors for grading TI-RADS categories of malignancy thyroid nodules. CONCLUSIONS: Ill-defined boundary, irregular shape and presence of calcification related with highly malignant risk for thyroid nodule. The larger height and aspect and presence of calcification related with higher TI-RADS classification of malignancy thyroid nodule.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Adulto , Idoso , Calcinose/diagnóstico por imagem , Diagnóstico por Computador , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Período Pós-Operatório , Período Pré-Operatório , Projetos de Pesquisa , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/cirurgia , Ultrassonografia
14.
Cancer Biol Med ; 9(2): 124-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23691467

RESUMO

OBJECTIVE: Real-time ultrasound elastography (US-E) is a helpful tool in diagnosing thyroid nodules. This study aims to evaluate thyroid solid nodules, to establish the accuracy of US-E in providing information on the nature of these nodules, and to assess the clinical value of elasticity scores (ES) and strain ratio (SR) in differentiating thyroid solid nodules and to explore its distribution characteristics using pathological analysis as reference. METHODS: Traditional ultrasonography and US-E were performed on 131 thyroid solid nodules (99 benign ones and 32 malignant ones) in 120 patients (78 females and 41 males). Three radiologists evaluated the nodules based on a four-degree elasticity scoring system. The nodules were classified according to the ES as soft (ES 1-2) or hard (ES 3-4). The SR was calculated online. RESULTS: The sensitivity and specificity of the ES for thyroid cancer diagnosis were 78% and 80%, respectively. SR values ≥ 2.9 used as a standard to distinguish benign from malignant nodules had a sensitivity of 87% and a specificity of 92%. The SR of the benign lesions was 1.64±1.37, which was significantly different from that of malignant lesions, which was 4.96±2.13 (P<0.01). CONCLUSIONS: Both the ES and SR were higher in malignant nodules than those in benign ones. Real-time US-E was a useful index in the differential diagnosis of thyroid solid nodules. It can provide quantitative information on thyroid nodule characterization and improve diagnostic confidence.

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