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1.
Angew Chem Int Ed Engl ; 63(28): e202404139, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38689425

RESUMO

Trisulfide unit is widely found in natural products and has garnered attention due to the unique pharmacological and physiochemical properties. However, despite limited progress, widely applicable approaches for constructing unsymmetrical trisulfides have so far remain scarce. In this work, an easy-to-prepare, solid-state and scalable reagent, S-substituted sulphenylthiosulphate, has been developed for the divergent synthesis of unsymmetrical trisulfides. Alkyl electrophile substrates, including bromides, chlorides, iodides and tosylates, with diverse substituents are smoothly converted to the corresponding trisulfides with S-substituted sulphenylthiosulphates and thiourea as another sulfur source. Furthermore, the late-stage modification of drug molecules was successfully achieved through this method.

2.
Int J Surg ; 110(5): 2910-2921, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38353702

RESUMO

OBJECTIVE: The objective of this study is to evaluate and compare the survival benefit and safety of surgery following conversion therapy versus surgery alone in patients diagnosed with surgically resectable hepatocellular carcinoma (HCC) at China Liver Cancer Staging (CNLC) IIb/IIIa stage. METHODS: A total of 95 patients diagnosed with surgically resectable CNLC IIb/IIIa HCC were retrospectively enrolled in our study from November 2018 to December 2022. Among them, 30 patients underwent conversion therapy followed by hepatectomy, while the remaining 65 received surgery alone. The primary endpoint was recurrence-free survival (RFS). Propensity score matching was employed to minimize bias in the retrospective analysis. RESULTS: Compared to the surgery alone group, the conversion therapy group demonstrated a significantly prolonged median RFS (17.1 vs. 7.0 months; P =0.014), a reduced incidence of microvascular invasion (MVI, 23.3 vs. 81.5%; P <0.001), and a comparable rate of achieving Textbook Outcome in Liver Surgery (TOLS, 83.3 vs. 76.9%; P =0.476). Multivariate analysis indicated that conversion therapy was independently associated with improved RFS after hepatectomy (HR=0.511, P =0.027). The same conclusions were obtained after propensity score matching. CONCLUSIONS: The findings of our study offer preliminary evidence that preoperative conversion therapy significantly prolongs RFS in patients with surgically resectable HCC at CNLC IIb/IIIa stage. Furthermore, combining conversion therapy and hepatectomy represents a relatively safe treatment strategy.


Assuntos
Carcinoma Hepatocelular , Hepatectomia , Neoplasias Hepáticas , Estadiamento de Neoplasias , Pontuação de Propensão , Humanos , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Hepatectomia/efeitos adversos , Hepatectomia/métodos , Estudos Retrospectivos , Idoso , China/epidemiologia , Adulto
3.
Dig Dis ; 42(3): 221-229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38342087

RESUMO

INTRODUCTION: The objective of our study was to develop a nomogram to predict overall survival (OS) and cancer-specific survival (CSS) in patients with gastric signet ring cell carcinoma (GSRCC). METHODS: A total of 3,408 GSRCC patients between 1975 and 2017 were screened from the Surveillance, Epidemiology, and End Results (SEER) database and randomly divided into training and validation cohorts. Univariate and multivariate Cox analyses were conducted to identify independent prognostic factors for the construction of a nomogram. The performance of the model was then assessed by the concordance index (C-index), calibration plot, and area under the receiver operating characteristic curve (AUC). Then, the novel nomogram was further assessed by 64 GSRCC patients from our hospital as the external cohort. RESULTS: We identified age, tumor lymph node metastasis (TNM) staging system, surgery, and chemotherapy as significant independent elements of prognosis. On this basis, a nomogram was constructed, with a C-index of OS in the training and validation cohorts of 0.763 (95% CI: 0.751-0.774) and 0.766 (95% CI: 0.748-0.784) and a C-index of CSS of 0.765 (95% CI: 0.753-0.777) and 0.773 (95% CI: 0.755-0.791), respectively. The AUCs of the nomogram for predicting 2- and 5-year OS were 0.848 and 0.885, respectively, and those for predicting CSS were 0.854 and 0.899, respectively, demonstrating the excellent predictive value of the constructed nomogram compared to the traditional AJCC staging system. Similar results were also observed in both the internal and external validation sets. CONCLUSION: The nomogram provided an accurate tool to predict OS and CSS in patients with GSRCC, which can assist clinicians in making predictions about individual patient survival.


Assuntos
Carcinoma de Células em Anel de Sinete , Nomogramas , Programa de SEER , Neoplasias Gástricas , Humanos , Carcinoma de Células em Anel de Sinete/mortalidade , Carcinoma de Células em Anel de Sinete/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Prognóstico , Idoso , Adulto , Estadiamento de Neoplasias , Curva ROC , Modelos de Riscos Proporcionais
4.
Opt Express ; 31(25): 42613-42623, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38087631

RESUMO

Spectral imaging is a powerful tool in industrial processes, medical imaging, and fundamental scientific research. However, for the commonly used spatial/spectral-scanning spectral imager, the slow response time has posed a big challenge for its employment in dynamic scenes. In this paper, we propose a spatiotemporal modulation concept and build a simple, low-cost spectral imager by combining a liquid crystal (LC) cell with a commercial color camera. By the synergic effect of temporal modulation of the LC materials and spatial modulation of the Bayer filter in a color camera, high-quality multispectral imaging is successfully demonstrated with a high rate of 8 Hz, far beyond the counterparts. Experimental results show that even with three tuning states of the LC material, optical signals with a 10-nm band can be resolved in the range between 410 and 700 nm by this method, overcoming the tradeoff between spectral resolution and time resolution. As a proof of demonstration, we present its potential usage for metamerism recognition, showing superiority over traditional color cameras with more spectral details. Considering its low cost, miniaturization and monolithic-integration ability on color sensors, this simple approach may bring the spectral imaging technology closer to the consumer market and even to ubiquitous smartphones for health care, food inspection and other applications.

5.
Opt Express ; 31(20): 33435-33448, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859126

RESUMO

Due to a great many superior features of infrared light communication (ILC), like high capacity and strong privacy, ILC is considered a potential candidate for serving the high demands of beyond fifth-generation/sixth-generation (B5G/6 G) communication systems. However, the terminal's limited field-of-view (FOV) induces great difficulty in establishing line-of-sight (LoS) link between the transceiver and the terminal. In this paper, we propose a wide-FOV auto-coupling optical antenna system that utilizes a wide-FOV telecentric lens to collect incident infrared beams and automatically couple them into a specific single-mode-fiber (SMF) channel of fiber array and optical switch. The performance of this optical antenna system is assessed through simulation and manual alignment operation, and validated by automatic alignment results. A coupling loss of less than 10.6 dB within a FOV of 100° for both downstream and upstream beams in C band is demonstrated by the designed system. Furthermore, we establish a bidirectional optical wireless communications (OWC) system employing this antenna and a fiber-type modulating retro-reflector (MRR) system in the terminal. Both 10-Gbps on-off keying (OOK) downstream and upstream transmissions are successfully realized with the FOV of up to 100° in C band where the measured bit-error-rate (BER) is lower than 3.8 × 10-3. To the best of our knowledge, this is a brand-new auto-coupling optical antenna system with the largest FOV in ILC automatic alignment works in terminals that have ever been reported.

6.
Macromol Rapid Commun ; 44(20): e2300298, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37548089

RESUMO

This work introduces a novel multifunctional system called UPIPF (upconversion-polydopamine-indocyanine-polyethylene-folic) for upconversion luminescent (UCL) imaging of cancer cells using near-infrared (NIR) illumination. The system demonstrates efficient inhibition of human hepatoma (HepG2) cancer cells through a combination of NIR-triggered photodynamic therapy (PDT) and enhanced photothermal therapy (PTT). Initially, upconversion nanoparticles (UCNP) are synthesized using a simple thermal decomposition method. To improve their biocompatibility and aqueous dispersibility, polydopamine (PDA) is introduced to the UCNP via a ligand exchange technique. Indocyanine green (ICG) molecules are electrostatically attached to the surface of the UCNP-polydopamine (UCNP@PDAs) complex to enhance the PDT and PTT effects. Moreover, polyethylene glycol (PEG)-modified folic acid (FA) is incorporated into the UCNP-polydopamine-indocyanine-green (UCNP@PDA-ICGs) nanoparticles to enhance their targeting capability against cancer cells. The excellent UCL properties of these UCNP enable the final UCNP@PDA-ICG-PEG-FA nanoparticles (referred to as UPIPF) to serve as a potential candidate for efficient anticancer drug delivery, real-time imaging, and early diagnosis of cancer cells. Furthermore, the UPIPF system exhibits PDT-assisted PTT effects, providing a convenient approach for efficient cancer cell inhibition (more than 99% of cells are killed). The prepared UPIPF system shows promise for early diagnosis and simultaneous treatment of malignant cancers.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Verde de Indocianina/farmacologia , Verde de Indocianina/uso terapêutico , Indóis/farmacologia , Polímeros/farmacologia , Polietilenoglicóis , Fotoquimioterapia/métodos , Linhagem Celular Tumoral , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
7.
Opt Express ; 31(10): 15342-15354, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157638

RESUMO

We explore the influence of the artificial atomic chain on the input-output relation of the cavity. Specifically, we extend the atom chain to the one-dimensional Su-Schrieffer-Heeger (SSH) chain to check the role of atomic topological non-trivial edge state on the transmission characteristics of the cavity. The superconducting circuits can realize the artificial atomic chain. Our results show that the atom chain is not equivalent to atom gas, and the transmission properties of the cavity containing the atom chain are entirely different from that of the cavity containing atom gas. When the atom chain is arranged in the form of topological non-trivial SSH model, the atom chain can be equivalent to the three-level atom, in which the edge state contributes to the second level and is resonant with the cavity, while the high-energy bulk state contributes to form the third level and is greatly detuned with the cavity. Therefore, the transmission spectrum shows no more than three peaks. This allows us to infer the topological phase of the atomic chain and the coupling strength between the atom and the cavity only from the profile of the transmission spectrum. Our work is helping to understand the role of topology in quantum optics.

8.
Phys Rev Lett ; 129(18): 187601, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36374677

RESUMO

1T-TiSe_{2} is one of the most studied charge density wave (CDW) systems, not only because of its peculiar properties related to the CDW transition, but also due to its status as a promising candidate of exciton insulator signaled by the proposed plasmon softening at the CDW wave vector. Using high-resolution electron energy loss spectroscopy, we report a systematic study of the temperature-dependent plasmon behaviors of 1T-TiSe_{2}. We unambiguously resolve the plasmon from phonon modes, revealing the existence of Landau damping to the plasmon at finite momentums, which does not support the plasmon softening picture for exciton condensation. Moreover, we discover that the plasmon lifetime at zero momentum responds dramatically to the band gap evolution associated with the CDW transition. The interband transitions near the Fermi energy in the normal phase are demonstrated to serve as a strong damping channel of plasmons, while such a channel in the CDW phase is suppressed due to the CDW gap opening, which results in the dramatic tunability of the plasmon in semimetals or small-gap semiconductors.

9.
J Oncol ; 2022: 9636790, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339648

RESUMO

Objectives: Primary gastric diffuse large B-cell lymphoma (PG-DLBCL) is a common phenotype of extranodal non-Hodgkin's lymphoma (NHL). This research aims to identify a model for predicting overall survival (OS) and cancer-specific survival (CSS) in PG-DLBCL. Methods: A total of 1716 patients diagnosed with PG-DLBCL between 1975 and 2017 were obtained from the SEER database and further randomly divided into the training and validating cohorts at a ratio of 7 : 3. Univariate and multivariate cox analyses were conducted to determine significant variables for the construction of nomogram. The performance of the model was then assessed by the concordance index (C-index), the calibration plot, and the area under the receiver operating characteristic (ROC) curve (AUC). Results: Multivariate analysis revealed that age, race, insurance status, Ann Arbor stage, marital status, chemotherapy, and radiation therapy all showed a significant association with OS and CSS. These characteristics were applied to build a nomogram. In the training cohort, the discrimination of nomogram for OS and CSS prediction was excellent (C-index = 0.764, 95% CI, 0.744-0.784 and C-index = 0.756, 95% CI, 0.732-0.780). The AUC of the nomogram for predicting 3- and 5-year OS was 0.779 and 0.784 and CSS was 0.765 and 0.772. Similar results were also observed in the internal validation set. Conclusions: We have successfully established a novel nomogram for predicting OS and CSS in PG-DLBCL patients with good accuracy, which can help physicians to quickly and accurately complete the evaluation of survival probability, risk stratification, and therapeutic strategy at diagnosis.

10.
Nat Commun ; 12(1): 2447, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33907193

RESUMO

The d-band-filling of transition metals in complex oxides plays an essential role in determining their structural, electronic and magnetic properties. Traditionally, at the oxide heterointerface, band-filling control has been achieved via electrostatic modification in the structure of field-effect transistors or electron transfer, which is limited to the quasi-two-dimension at the interface. Here we report a three-dimensional (3D) band-filling control by changing the local lattice coordination in a designed oxide heterostructure. At the LaCoO3/LaTiO3 heterointerface, due to the Fermi level mismatch, electrons transfer from LaTiO3 to LaCoO3. This triggers destabilisation of the CoO6 octahedrons, i.e. the formation of lattice configurations with a reduced Co valence. The associated oxygen migration results in the 3D topotactic phase transition of LaCoO3. Tuned by the thickness of LaTiO3, different crystalline phases and band-fillings of Co occur, leading to the emergence of different magnetic ground states.

11.
Immunol Invest ; 48(8): 809-821, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31405308

RESUMO

Aims The aryl hydrocarbon receptor (AhR) plays a pivotal role in regulating the innate and the acquired immune systems. The present study aimed to investigate the association of Crohn's disease (CD) with AhR polymorphisms in a cohort of patients from Southeast China. Methods An improved multiple ligase detection reaction technique was applied to examine the polymorphisms of rs2158041, rs2066853, and rs10249788 in 310 patients with CD and 573 controls. Results Compared to the controls, the variant allele (T) and genotype (CT+TT) of rs2158041 were less frequent in patients with CD (both p < 0.05). Similar conclusions were drawn from patients with ileal CD and with stricture CD as compared to the controls (all p < 0.0083). However, no significant differences were observed in allele and genotype frequencies of rs2066853 and rs10249788 between patients with CD and the controls (all p > 0.05). Although rs2158041 and rs10249788 were in complete linkage disequilibrium with rs2066853, respectively, only the frequency of haplotype (TG) formed by rs2158041 and rs2066853 was significantly lower in patients with CD than that in the controls (p < 0.05). Conclusions AhR (rs2158041) might be a susceptible locus for CD, especially for the two subtypes: ileal CD and stricture CD.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Doença de Crohn/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único , Receptores de Hidrocarboneto Arílico/genética , Adulto , Alelos , Povo Asiático/genética , China , Doença de Crohn/etnologia , Feminino , Frequência do Gene , Predisposição Genética para Doença/etnologia , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Gastroenterol Res Pract ; 2019: 4052168, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30918515

RESUMO

Abnormalities of forkhead box P3 (FOXP3) are implicated in various autoimmune diseases. This study is aimed at investigating the association of ulcerative colitis (UC) with FOXP3 polymorphisms and its colonic expression in Chinese patients. Polymorphisms of rs3761548, rs2232365, rs2294021, and rs3761547 were examined in 472 UC patients and 525 healthy controls using the SNaPshot method. The colonic expression of FOXP3 mRNA and protein was assayed in inflammatory mucosa of 34 UC patients and normal mucosa of 36 patients with benign sigmoid polyps (normal controls) using real-time quantitative polymerase chain reaction and immunohistochemical analysis. All data were handled separately for females and males. As a result, the carrier frequencies with at least one variant allele of rs3761548, rs2232365, and rs229402 increased in female and male UC patients compared with healthy controls. Significant differences in these carrier frequencies were also observed between patients with mild and moderate UC and patients with severe UC. The expression of FOXP3 was higher in UC patients (both males and females), especially those with severe UC, than in normal controls. The expression of FOXP3 was downregulated in UC patients having at least one variant allele compared with UC patients having no variant allele of rs3761548, rs2232365, and rs2294021. Male gender (ß = -0.341), rs2294021 variation (ß = -0.503), and severe UC (ß = 0.361) were independently related to the mRNA expression of FOXP3 in UC patients. Together, our findings indicated that FOXP3 (rs3761548, rs2232365, and rs2294021) variations increased the risk of UC and were associated with the lower colonic expression of FOXP3 in UC patients.

13.
Genet Test Mol Biomarkers ; 22(10): 607-614, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30260678

RESUMO

BACKGROUND AND AIMS: The Fc gamma receptor IIa (FcγRIIa), encoded by FCGR2A gene, has been suggested to play a crucial role in immunity by linking immunoglobulin G antibody-mediated responses with cellular effector and regulatory functions. Polymorphisms in FCGR2A have been shown to affect FcγRIIa/antibody interactions and have been potentially implicated in several autoimmune and inflammatory conditions. This study was designed to analyze the association between ulcerative colitis (UC) and FCGR2A polymorphisms in the Chinese population. MATERIALS AND METHODS: A total of 422 patients with UC and 710 unaffected controls were recruited. Five single nucleotide polymorphisms of FCGR2A (rs1801274, rs10800309, rs4657039, rs511278, and rs6696854) were genotyped by SNaPshot. Analyses for linkage disequilibrium (LD) and haplotype studies of FCGR2A were performed for all study subjects. RESULTS: The frequency of the minor homozygote (CC) of the rs1801274 SNP of FCGR2A was shown to be significantly lower in patients with UC than in controls (7.1% vs. 12.1%, p = 0.008). Two haplotype blocks, formed by FCGR2A (rs4657039, rs6696854, and rs10800309) and FCGR2A (rs1801274 and rs511278), respectively, were observed in the subsequent LD analysis. The TC haplotype constructed by the major allele of FCGR2A (rs1801274 and rs511278) was more prevalent in UC patients compared with controls (65.2% vs. 60.2%, p = 0.017). CONCLUSIONS: The minor homozygote (CC) of FCGR2A (rs1801274) may contribute to decrease the susceptibility to UC and the TC haplotype formed by FCGR2A (rs1801274 and rs511278) may increase the risk of UC in the Chinese population.


Assuntos
Colite Ulcerativa/genética , Receptores de IgG/genética , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , Colite Ulcerativa/metabolismo , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Receptores de IgG/metabolismo , Fatores de Risco
14.
Adv Mater ; 30(30): e1802065, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29894006

RESUMO

Two-dimensional (2D) in-plane p-n junctions with a continuous interface have great potential in next-generation devices. To date, the general fabrication strategies rely on lateral epitaxial growth of p- and n-type 2D semiconductors. An in-plane p-n junction is fabricated with homogeneous monolayer Te at the step edge on graphene/6H-SiC(0001). Scanning tunneling spectroscopy reveals that Te on the terrace of trilayer graphene is p-type, and it is n-type on monolayer graphene. Atomic-resolution images demonstrate the continuous lattice of the junction, and mappings of the electronic states visualize the type-II band bending across the space-charge region of 6.2 nm with a build-in field of 4 × 105 V cm-1 . The reported strategy can be extended to other 2D semiconductors on patternable substrates for designed fabrication of in-plane junctions.

15.
Nano Lett ; 17(8): 4619-4623, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28657748

RESUMO

Tellurium (Te) films with monolayer and few-layer thickness are obtained by molecular beam epitaxy on a graphene/6H-SiC(0001) substrate and investigated by in situ scanning tunneling microscopy and spectroscopy (STM/STS). We reveal that the Te films are composed of parallel-arranged helical Te chains flat-lying on the graphene surface, exposing the (1 × 1) facet of (101̅0) of the bulk crystal. The band gap of Te films increases monotonically with decreasing thickness, reaching the near-infrared band for the monolayer Te. An explicit band bending at the edge between the monolayer Te and graphene substrate is visualized. With the thickness controlled in the atomic scale, Te films show potential applications of electronics and optoelectronics.

16.
Plant Mol Biol ; 88(3): 219-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25924595

RESUMO

Dendrobium officinale is a traditional Chinese medicinal plant. The stems of D. officinale contain mannan polysaccharides, which are promising bioactive polysaccharides for use as drugs. However, the genes involved in the biosynthesis of mannan polysaccharides in D. officinale have not yet been identified. In this study, four digital gene expression profiling analyses were performed on developing stems of greenhouse-grown D. officinale to identify such genes. Based on the accumulation of mannose and on gene expression levels, eight CELLULOSE SYNTHASE-LIKE A genes (CSLA), which are highly likely to be related to the biosynthesis of bioactive mannan polysaccharides, were identified from the differentially expressed genes database. In order to further analyze these DoCSLA genes, a full-length cDNA of each was obtained by RACE. The eight genes, belonging to the CSLA family of the CesA superfamily, contain conserved domains of the CesA superfamily. Most of the genes, which were highly expressed in the stems of D. officinale, were related to abiotic stress. Our results suggest that the CSLA family genes from D. officinale are involved in the biosynthesis of bioactive mannan polysaccharides.


Assuntos
Dendrobium/genética , Genes de Plantas , Mananas/biossíntese , Análise de Sequência de RNA , Clonagem Molecular , Perfilação da Expressão Gênica , Filogenia , Reação em Cadeia da Polimerase em Tempo Real
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