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1.
Small ; : e2307482, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38412428

RESUMO

Manganese-based oxides (MnOx ) suffer from sluggish charge diffusion kinetics and poor cycling stability in sodium ion storage. Herein, an interfacial electric field (IEF) in CeO2 /MnOx is constructed to obtain high electronic/ionic conductivity and structural stability of MnOx . The as-designed CeO2 /MnOx exhibits a remarkable capacity of 397 F g-1 and favorable cyclic stability with 92.13% capacity retention after 10,000 cycles. Soft X-ray absorption spectroscopy and partial density of states results reveal that the electrons are substantially injected into the Mn t2g orbitals driven by the formed IEF. Correspondingly, the MnO6 units in MnOx are effectively activated, endowing the CeO2 /MnOx with fast charge transfer kinetics and high sodium ion storage capacity. Moreover, In situRaman verifies a remarkably increased structural stability of CeO2 /MnOx , which is attributed to the enhanced Mn─O bond strength and efficiently stabilized MnO6 units. Mechanism studies show that the downshift of Mn 3d-band center dramatically increases the Mn 3d-O 2p orbitals overlap, thus inhibiting the Jahn-Teller (J-T) distortion of MnOx during sodium ion insertion/extraction. This work develops an advanced strategy to achieve both fast and sustainable sodium ion storage in metal oxides-based energy materials.

2.
Bioorg Med Chem Lett ; 99: 129598, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38169246

RESUMO

The synthesis of compounds based on fragments derived from natural products (NPs) serves as a source of inspiration for the design of pseudo-natural products (PNPs), to identify bioactive molecules that exhibit similar characteristics to NPs. These novel molecular scaffolds exhibit previously unexplored biological activities as well. This study reports the development and synthesis of a novel pentacyclic ring system, the indole-pyrimidine-quinoline (IPQ) scaffold. The design of this scaffold was based on the structural characteristics of four natural products, namely tryptanthrin, luotonin A, rutaecarpine, and camptothecin. Several successive steps accomplished the effective synthesis of the IPQ scaffold. The constituent components of the pentacycle, containing the indole, quinazolinone, pyrimidone, and quinoline units, possess significant biological significance. Compound 1a demonstrated noteworthy anti-tumor activity efficacy against A549 cell lines among the tested compounds. The compound 1a was observed to elicit cell cycle arrest in both the G2/M and S phases, as well as trigger apoptosis in A549 cells. These effects were attributed to its ability to modulate the activation of mitochondrial-related mitogen-activated protein kinase (MAPK) signaling pathways.


Assuntos
Antineoplásicos , Produtos Biológicos , Quinolinas , Antineoplásicos/química , Apoptose , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Camptotecina/farmacologia , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Quinolinas/farmacologia , Indóis/química , Indóis/farmacologia , Pirimidinas
3.
Int J Mol Sci ; 25(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38892414

RESUMO

Berberine (BBR) is used to treat cancer, inflammatory conditions, and so on. But the side effects of BBR causing constipation should not be ignored. In clinical application, the combination of Amomum villosum Lour. (AVL) and BBR can relieve it. However, the effective ingredients and molecular mechanism of AVL in relieving constipation are not clear. A small intestine propulsion experiment was conducted in constipated mice to screen active ingredients of AVL. We further confirmed the molecular mechanism of action of the active ingredient on BBR-induced constipation. Quercetin (QR) was found to be the effective ingredient of AVL in terms of relieving constipation. QR can efficiently regulate the microbiota in mice suffering from constipation. Moreover, QR significantly raised the levels of substance P and motilin while lowering those of 5-hydroxytryptamine and vasoactive intestinal peptide; furthermore, it also increased the protein expression levels of calmodulin, myosin light-chain kinase, and myosin light chain. The use of QR in combination with BBR has an adverse effect-reducing efficacy. The study provides new ideas and possibilities for the treatment of constipation induced by BBR.


Assuntos
Berberina , Constipação Intestinal , Microbioma Gastrointestinal , Quercetina , Animais , Berberina/farmacologia , Berberina/uso terapêutico , Quercetina/farmacologia , Constipação Intestinal/tratamento farmacológico , Constipação Intestinal/induzido quimicamente , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Masculino , Modelos Animais de Doenças , Motilina/metabolismo
4.
Angew Chem Int Ed Engl ; 63(23): e202404834, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38588076

RESUMO

Transition metal oxides (TMOs) are key in electrochemical energy storage, offering cost-effectiveness and a broad potential window. However, their full potential is limited by poor understanding of their slow reaction kinetics and stability issues. This study diverges from conventional complex nano-structuring, concentrating instead on spin-related charge transfer and orbital interactions to enhance the reaction dynamics and stability of TMOs during energy storage processes. We successfully reconfigured the orbital degeneracy and spin-dependent electronic occupancy by disrupting the symmetry of magnetic cobalt (Co) sites through straightforward strain stimuli. The key to this approach lies in the unfilled Co 3d shell, which serves as a spin-dependent regulator for carrier transfer and orbital interactions within the reaction. We observed that the opening of these 'spin gates' occurs during a transition from a symmetric low-spin state to an asymmetric high-spin state, resulting in enhanced reaction kinetics and maintained structural stability. Specifically, the spin-rearranged Al-Co3O4 exhibited a specific capacitance of 1371 F g-1, which is 38 % higher than that of unaltered Co3O4. These results not only shed light on the spin effects in magnetic TMOs but also establish a new paradigm for designing electrochemical energy storage materials with improved efficiency.

5.
J Am Chem Soc ; 145(49): 26699-26710, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38039528

RESUMO

Transition-metal oxides (TMOs) often struggle with challenges related to low electronic conductivity and unsatisfactory cyclic stability toward cationic intercalation. In this work, we tackle these issues by exploring an innovative strategy: leveraging heightened π-donation to activate the t2g orbital, thereby enhancing both electron/ion conductivity and structural stability of TMOs. We engineered Ni-doped layered manganese dioxide (Ni-MnO2), which is characterized by a distinctive Ni-O-Mn bridging configuration. Remarkably, Ni-MnO2 presents an impressive capacitance of 317 F g-1 and exhibits a robust cyclic stability, maintaining 81.58% of its original capacity even after 20,000 cycles. Mechanism investigations reveal that the incorporation of Ni-O-Mn configurations stimulates a heightened π-donation effect, which is beneficial to the π-type orbital hybridization involving the O 2p and the t2g orbital of Mn, thereby accelerating charge-transfer kinetics and activating the redox capacity of the t2g orbital. Additionally, the charge redistribution from Ni to the t2g orbital of Mn effectively elevates the low-energy orbital level of Mn, thus mitigating the undesirable Jahn-Teller distortion. This results in a subsequent decrease in the electron occupancy of the π*-antibonding orbital, which promotes an overall enhancement in structural stability. Our findings pave the way for an innovative paradigm in the development of fast and stable electrode materials for intercalation energy storage by activating the low orbitals of the TM center from a molecular orbital perspective.

6.
Small ; 19(15): e2205666, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36670092

RESUMO

Transition metal oxides suffer from slow salt removal rate (SRR) due to inferior ions diffusion ability in hybrid capacitive deionization (HCDI). Local electric field (LEF) can efficiently improve the ions diffusion kinetics in thin electrodes for electrochemical energy storage. Nevertheless, it is still a challenge to facilitate the ions diffusion in bulk electrodes with high loading mass for HCDI. Herein, this work delicately constructs a LEF via engineering atomic-level donor (O vacancies)-acceptor (Mn atoms) couples, which significantly facilitates the ions diffusion and then enables a high-performance HCDI. The LEF boosts an extended accelerated ions diffusion channel at the particle surface and interparticle space, resulting in both remarkably enhanced SRR and salt removal capacity. Convincingly, the theoretical calculations demonstrate that electron-enriched Mn atoms center coupled with an electron-depleted O vacancies center is formed due to the electron back-donation from O vacancies to adjacent Mn centers. The resulted LEF efficiently reduce the ions diffusion energy barrier. This work sheds light on the effect of atomic-level LEF on improving ions diffusion kinetics at high loading mass application and paves the way for the design of transition metal oxides toward high-performance HCDI applications.

7.
Small ; 19(36): e2301717, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37118856

RESUMO

Internal electric field (IEF) construction is an innovative strategy to regulate the electronic structure of electrode materials to promote charge transfer processes. Despite the wide use of IEF in various applications, the underlying mechanism of its formation in an asymmetric TM-O-TM unit still remains poorly understood. Herein, the essential principles for the IEF construction at electron occupancy state level and explore its effect on hybrid capacitive deionization (HCDI) performance is systematically investigated. By triggering a charge separation in Ni-MnO2 via superexchange interactions in a coordination structure unit of Mn4+ -O2- -Ni2+ , the formation of an IEF that can enhance charge transfer during the HCDI process is demonstrated. Experimental and theoretical results confirm the electrons transfer from O 2p orbital to TM (Ni2+ and Mn4+ ) eg orbital via superexchange interactions in the basic Mn4+ -O2- -Ni2+ coordination unit. As a result of the charge redistribution, the IEF endows Ni-MnO2 with superior electron and ion transfer property. This work presents a unique material design strategy that activates the electrochemical performance, and provides insights into the formation mechanism of IEF in an asymmetric TM-O-TM unit, which has potential applications in the construction of other innovative materials.

8.
PLoS Biol ; 18(5): e3000746, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453802

RESUMO

Members of the Tre2-Bub2-Cdc16 (TBC) family often function to regulate membrane trafficking and to control signaling transductions pathways. As a member of the TBC family, TBC1D23 is critical for endosome-to-Golgi cargo trafficking by serving as a bridge between Golgi-bound golgin-97/245 and the WASH/FAM21 complex on endosomal vesicles. However, the exact mechanisms by which TBC1D23 regulates cargo transport are poorly understood. Here, we present the crystal structure of the N-terminus of TBC1D23 (D23N), which consists of both the TBC and rhodanese domains. We show that the rhodanese domain is unlikely to be an active sulfurtransferase or phosphatase, despite containing a putative catalytic site. Instead, it packs against the TBC domain and forms part of the platform to interact with golgin-97/245. Using the zebrafish model, we show that impacting golgin-97/245-binding, but not the putative catalytic site, impairs neuronal growth and brain development. Altogether, our studies provide structural and functional insights into an essential protein that is required for organelle-specific trafficking and brain development.


Assuntos
Autoantígenos/metabolismo , Encéfalo/embriologia , Proteínas Ativadoras de GTPase/metabolismo , Proteínas da Matriz do Complexo de Golgi/metabolismo , Tiossulfato Sulfurtransferase/metabolismo , Fatores de Ribosilação do ADP/metabolismo , Animais , Escherichia coli , Proteínas Ativadoras de GTPase/química , Proteínas Ativadoras de GTPase/isolamento & purificação , Células HEK293 , Células HeLa , Humanos , Proteínas de Membrana/metabolismo , Conformação Proteica , Domínios Proteicos , Peixe-Zebra
9.
Bioorg Med Chem Lett ; 80: 129127, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36634753

RESUMO

A series of pyrrolo[3,2-d]pyrimidineone compounds have been designed and synthesized as novel FXa inhibitors. Bioassay of the tested compounds showed moderate to excellent anticoagulant potency in vitro. Further FXa inhibitory and bioactivity evaluation in rats, the FeCl3-induced venous thrombosis model, showed that the compound 17a has good FXa inhibitory activity (IC50 = 1.57 nM) and in vivo antithrombotic potency. The anticoagulant effects of compound 17a were dose dependent whether in vitro or in vivo. The results further confirmed our hypothesis that the large conjugated structure is an ideal skeleton binding FXa.


Assuntos
Inibidores do Fator Xa , Trombose Venosa , Ratos , Animais , Fator Xa/metabolismo , Anticoagulantes
10.
Sensors (Basel) ; 24(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38203030

RESUMO

Due to the superior robustness of outlier signals and the unique advantage of not relying on a priori knowledge, Convolution Sparse Filtering (CSF) is drawing more and more attention. However, the excellent properties of CSF is limited by its inappropriate selection of the number and length of its filters. Therefore, the Adaptive Convolution Sparse Filtering (ACSF) method is proposed in this paper to implement an end-to-end health monitoring and fault diagnostic model. Firstly, a novel metric entropy-time function (He-T) is proposed to measure the accuracy and efficiency of signals filtered by the CSF. Then, the filtered signal with the minimum He-T is detected with particle swarm optimization. Finally, the failure mode is diagnosed according to the envelope spectrum of the signal with minimum He-T. The effectiveness and efficiency of the ACSF is demonstrated through the experiment. The results indicate the ACSF can extract the failure characteristic of the gearbox.

11.
Int J Mol Sci ; 24(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446006

RESUMO

The pathogenesis of ulcerative colitis (UC) is associated with inflammation, oxidative stress, and gut microbiota imbalance. Although most researchers have demonstrated the antioxidant bioactivity of the phenolic compounds in plants, their UC-curing ability and underlying mechanisms still need to be further and adequately explored. Herein, we studied the antioxidation-structure relationship of several common polyphenols in plants including gallic acid, proanthocyanidin, ellagic acid, and tannic acid. Furthermore, the in vivo effects of the plant polyphenols on C57BL/6 mice with dextran-sulfate-sodium-induced UC were evaluated and the action mechanisms were explored. Moreover, the interplay of several mechanisms was determined. The higher the number of phenolic hydroxyl groups, the stronger the antioxidant activity. All polyphenols markedly ameliorated the symptoms and pathological progression of UC in mice. Furthermore, inflammatory cytokine levels were decreased and the intestinal barrier was repaired. The process was regulated by the antioxidant-signaling pathway of nuclear-erythroid 2-related factor 2. Moreover, the diversity of the intestinal microbiota, Firmicutes-to-Bacteroides ratio, and relative abundance of beneficial bacteria were increased. An interplay was observed between microbiota regulation and oxidative stress, immunity, and inflammatory response. Furthermore, intestinal barrier repair was found to be correlated with inflammatory responses. Our study results can form a basis for comprehensively developing plant-polyphenol-related medicinal products.


Assuntos
Colite Ulcerativa , Microbiota , Animais , Camundongos , Camundongos Endogâmicos C57BL , Antioxidantes/farmacologia , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Fenóis
12.
Molecules ; 27(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36144733

RESUMO

BACKGROUND: Various potential effect of drugs on alleviating diseases by regulating intestinal microbiome as well as the pharmaceutical excipients on gut microbiota has been revealed. However, the interaction between them is rarely investigated. METHODS: Histological analysis, immunohistochemistry analysis, enzyme-linked immunosorbent assay (ELISA) analysis, RT-qPCR, and 16S rRNA analysis were utilized to explore the effect mechanism of the five excipients including hydroxypropyl methylcellulose (HPMC) F4M, Eudragit (EU) S100, chitosan (CT), pectin (PT), and rheum officinale polysaccharide (DHP) on berberine (BBR) to cure UC. RESULTS: The combined BBR with PT and DHP group exhibited better therapeutic efficacy of UC with significantly increased colon length, and decreased hematoxylin-eosin (H&E) scores than other groups. Furthermore, the expression of tight junction ZO-1 and occludin in colon tissue were upregulated, and claudin-2 was downregulated. Ultimately, the serum content of tumor necrosis (TNF)-α, interleukin (IL)-1ß, and IL-6 was decreased. Moreover, the combined BBR with PT significantly promoted the restoration of gut microbiota. The relative abundance of Firmicutes and Lactobacillus was significantly increased by the supplement of PT and DHP, and the relative abundance of Proteobacteria was downregulated. CONCLUSIONS: Our study may provide a new perspective that the selection of pharmaceutical excipients could be a crucial factor affecting the drugs' therapeutic efficiency outcome.


Assuntos
Berberina , Quitosana , Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Animais , Berberina/metabolismo , Quitosana/farmacologia , Claudina-2/metabolismo , Colite/patologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colo/metabolismo , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Amarelo de Eosina-(YS) , Excipientes/farmacologia , Hematoxilina/metabolismo , Hematoxilina/farmacologia , Hematoxilina/uso terapêutico , Humanos , Derivados da Hipromelose/metabolismo , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ocludina/metabolismo , Pectinas/farmacologia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
13.
Entropy (Basel) ; 23(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33916268

RESUMO

Domain adaptation-based models for fault classification under variable working conditions have become a research focus in recent years. Previous domain adaptation approaches generally assume identical label spaces in the source and target domains, however, such an assumption may be no longer legitimate in a more realistic situation that requires adaptation from a larger and more diverse source domain to a smaller target domain with less number of fault classes. To address the above deficiencies, we propose a partial transfer fault diagnosis model based on a weighted subdomain adaptation network (WSAN) in this paper. Our method pays more attention to the local data distribution while aligning the global distribution. An auxiliary classifier is introduced to obtain the class-level weights of the source samples, so the network can avoid negative transfer caused by unique fault classes in the source domain. Furthermore, a weighted local maximum mean discrepancy (WLMMD) is proposed to capture the fine-grained transferable information and obtain sample-level weights. Finally, relevant distributions of domain-specific layer activations across different domains are aligned. Experimental results show that our method could assign appropriate weights to each source sample and realize efficient partial transfer fault diagnosis.

14.
Entropy (Basel) ; 23(8)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34441215

RESUMO

Fault diagnosis of mechanical equipment is mainly based on the contact measurement and analysis of vibration signals. In some special working conditions, the non-contact fault diagnosis method represented by the measurement of acoustic signals can make up for the lack of contact testing. However, its engineering application value is greatly restricted due to the low signal-to-noise ratio (SNR) of the acoustic signal. To solve this deficiency, a novel fault diagnosis method based on the generalized matrix norm sparse filtering (GMNSF) is proposed in this paper. Specially, the generalized matrix norm is introduced into the sparse filtering to seek the optimal sparse feature distribution to overcome the defect of low SNR of acoustic signals. Firstly, the collected acoustic signals are randomly overlapped to form the sample fragment data set. Then, three constraints are imposed on the multi-period data set by the GMNSF model to extract the sparse features in the sample. Finally, softmax is used to as a classifier to categorize different fault types. The diagnostic performance of the proposed method is verified by the bearing and planetary gear datasets. Results show that the GMNSF model has good feature extraction ability performance and anti-noise ability than other traditional methods.

15.
Entropy (Basel) ; 23(8)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34441193

RESUMO

The domain adaptation problem in transfer learning has received extensive attention in recent years. The existing transfer model for solving domain alignment always assumes that the label space is completely shared between domains. However, this assumption is untrue in the actual industry and limits the application scope of the transfer model. Therefore, a universal domain method is proposed, which not only effectively reduces the problem of network failure caused by unknown fault types in the target domain but also breaks the premise of sharing the label space. The proposed framework takes into account the discrepancy of the fault features shown by different fault types and forms the feature center for fault diagnosis by extracting the features of samples of each fault type. Three optimization functions are added to solve the negative transfer problem when the model solves samples of unknown fault types. This study verifies the performance advantages of the framework for variable speed through experiments of multiple datasets. It can be seen from the experimental results that the proposed method has better fault diagnosis performance than related transfer methods for solving unknown mechanical faults.

16.
J Ultrasound Med ; 38(6): 1491-1499, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30380169

RESUMO

OBJECTIVES: To explore the best individualized systematic prostate biopsy method. METHODS: We retrospectively analyzed the clinical data of 1211 patients who underwent 12-core systematic prostate biopsy guided by transrectal ultrasound from January 2011 to March 2018. Other biopsy core methods (6-, 8-, and 10-core) were estimated from the 12-core biopsy that was performed. Differences in the detection rates of prostate cancer (PCa) and clinically significant prostate cancer (csPCa) were compared. RESULTS: A total of 498 cases of PCa (41.1%) were detected, and 423 cases (34.9%) were csPCa. There was no significant difference between the 12- and 10-core prostate biopsy strategies in the total detection rates of PCa and csPCa (P > .05). In the subgroup of patients with a maximal prostate cross-sectional area of less than 15 cm2 , there was a significant difference between the 12-core method and the standard 6-core method (P = .03) but no significant differences between the other methods in the detection rate of PCa (P > .05), but in the detection rate of csPCa, the 12-core method differed significantly from the other methods (P = .02-.04) except for the 10-core method (P > .05). In patients with a prostate-specific antigen concentration of 20 ng/mL or higher, there were no significant differences between the 12-core method and all of the other methods (P > 0.05). In patients younger than 70 years and 70 years or older, the 12-core method differed significantly from the other methods (P < .01-.03) except for the 10-core method (P > .05). CONCLUSIONS: Ten- or 12-core biopsy showed a higher detection rate than the other schemes. However, for patients with a prostate-specific antigen concentration of 20 ng/mL or higher, the 6-core systematic biopsy is preferred.


Assuntos
Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Ultrassonografia de Intervenção/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia com Agulha de Grande Calibre/métodos , Humanos , Biópsia Guiada por Imagem/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Próstata/diagnóstico por imagem , Próstata/patologia , Reprodutibilidade dos Testes , Estudos Retrospectivos
17.
J Ultrasound Med ; 38(1): 91-96, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29708283

RESUMO

OBJECTIVES: In this study, we retrospectively reviewed the clinical and sonographic features of patients with trichilemmal cysts. METHODS: Sonographic findings of 54 cases of trichilemmal cysts were retrospectively analyzed from 50 patients, including 4 cases of proliferating trichilemmal cysts. Associated factors of internal calcification-positive cases were also evaluated. RESULTS: The mean age of the 50 patients was 43.4 years (range, 15-80 years) and the female-to-male ratio was 1.3. Overall, 68% of the trichilemmal cysts in the 54 lesions were located in the scalp, and 15% were located in the extremities. All 54 lesions were preoperatively examined by sonography and showed well-defined, oval-shaped structures located in subcutaneous soft tissues close to the dermis. Of the 54 lesions, 72% were hypoechoic masses, 89% were heterogeneous, and 65% had internal calcification. Among the internal calcification-positive cases, the mean age of the patients was 43.4 years, and the female-to-male ratio was 0.6. Of these lesions, 83% were located in the scalp. We did not find any significant association between calcification, age, or sex (P = .993 and P = .99); however, lesions present in the scalp were significantly associated with internal calcification (P = .005). 81% of the 54 lesions displayed posterior enhancement. but the color Doppler sonography of all lesions revealed no vascularization. CONCLUSIONS: Trichilemmal cysts should be considered to diagnose of well-defined, hypoechoic lesions with internal calcification and posterior sound enhancement in the subcutaneous soft tissues of the scalp or extremities upon sonography.


Assuntos
Cisto Epidérmico/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Extremidades/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Couro Cabeludo/diagnóstico por imagem , Ultrassonografia/métodos , Adulto Jovem
18.
J Ultrasound Med ; 37(1): 93-98, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28708274

RESUMO

OBJECTIVES: To assess the diagnostic accuracy and performance of 360° endoanal sonography for preoperative evaluation of perianal fistulas using surgical results as a reference standard. METHODS: Between January 2012 and May 2016, 122 patients with suspicious anal fistulas and perianal abnormalities had real-time endoanal sonographic examinations using a 360° cross-sectional endoanal transducer (5-13 MHz) for preoperative evaluation of the disease. All patients underwent surgical interventions. The sonographic findings, including the fistulas and other inflammatory lesions, were correlated with surgical results. The types of fistulas on endoanal sonography were compared with the surgical classification of Parks et al (Br J Surg 1976; 63:1-2), and the internal opening of the fistula on endoanal sonography was confirmed by surgical results as a reference standard. RESULTS: The 122 patients studied included 111 male and 11 female patients. Endoanal sonography was able to show and track hypoechoic lesions, their locations, and internal openings of the fistulas. Compared with surgical results, endoanal sonography had sensitivity of 92.2%, specificity of 100%, and accuracy of 93.4% for the diagnosis of perianal fistulas. Also, endoanal sonography had accuracy of 87.4% for determining fistula types based on the Parks classification and 94.6% for identifying internal openings of the fistulas. CONCLUSIONS: Endoanal sonography is an accurate and noninvasive imaging modality for evaluation of fistulas. It is a very useful tool for preoperative management and surgical planning by providing precise and detailed information on fistulas.


Assuntos
Canal Anal/diagnóstico por imagem , Endossonografia/instrumentação , Endossonografia/métodos , Fístula Retal/diagnóstico por imagem , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Transdutores , Adulto Jovem
19.
J Nanosci Nanotechnol ; 16(3): 2201-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27455619

RESUMO

This paper successfully fabricated a novel multifunctional theranostic agent (PFOB@PLA/GO/Gd-DTPA NCs) by loading perfluorooctylbromide (PFOB) into poly(lactic acid) (PLA) nanocapsules (NCs) followed by surface functionalization with graphene oxide (GO) and gadolinium-chelate (Gd-DTPA). It was found that the resulting nanoagent could serve as a contrast agent simultaneously to enhance ultrasound (US) and magnetic resonance imaging (MRI). Benefiting from the strong absorption in the near infrared (NIR) region, the nanocapsules could efficiently kill cancer cells under NIR laser irradiation. Thus, such a single theranostic agent with the combination of realtime US imaging and high-resolution MR imaging could achieve great therapeutic effectiveness without systemic damage to the body. In addition, the cytotoxicity assay on HUVEC cells revealed a good biocompatibility of PFOB@PLA/GO/Gd-DTPA NCs, showing that the versatile nanocapsule system may hold great potential as an effective nanoplatform for contrast enhanced imaging guided photothermal therapy.


Assuntos
Quelantes/química , Fluorocarbonos/administração & dosagem , Gadolínio/química , Grafite/química , Ácido Láctico/química , Nanocápsulas , Neoplasias/terapia , Polímeros/química , Materiais Biocompatíveis , Fluorocarbonos/química , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrocarbonetos Bromados , Hipertermia Induzida , Imageamento por Ressonância Magnética/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Óxidos/química , Fototerapia , Poliésteres , Ultrassonografia/métodos
20.
J Nanosci Nanotechnol ; 16(3): 2184-93, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27455617

RESUMO

A theranostic agent has been successfully constructed for fluorescence/ultrasound dual-modal imaging guided photothermal therapy by loading the fluorescent dye R6G into polylactide microcapsules (PLA MCs) followed by deposition of Prussian blue nanoparticles (PB NPs) into the surface of PLA MCs. It was proved that the obtained microcapsules of R6G@PLA/PB MCs could serve as an efficient probe to simultaneously enhance fluorescence imaging and ultrasound imaging greatly in vivo. R6G@PLA/PB MCs exhibited significant photothermal cytotoxicity. Cancer cells could be killed efficiently through photothermal effects of R6G@PLA/PB MCs due to the strong absorption of PB NPs in the near infrared region under laser irradiation. In a word, R6G@PLA/PB MCs integrate multiple capabilities for effective tumor imaging and therapy. Such a single agent provides us a possibility to interpret accurately the obtained images, identify the size and location of the tumor, as well as guide and monitor the photothermal therapy.


Assuntos
Cápsulas , Ferrocianetos/química , Hipertermia Induzida , Ácido Láctico/química , Neoplasias/terapia , Fototerapia , Polímeros/química , Animais , Feminino , Fluorescência , Células HeLa , Humanos , Masculino , Poliésteres , Coelhos , Ultrassom
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