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1.
Dalton Trans ; 52(41): 14742-14746, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37823276

RESUMO

A new beryllium-free deep-UV transparent NLO crystal Li(H2O)2Sc(SO4)2 features a two-dimensional [Sc(SO4)2] framework consisting of twisted [Sc3S4O9] units decorated by [LiO2(H2O)2] groups into a unique layer. Remarkably, Li(H2O)2Sc(SO4)2 exhibits a phase-matching SHG response of 0.7 × KDP and a deep-UV cutoff edge below 190 nm.

2.
J Gastrointest Oncol ; 13(4): 2048-2056, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36092335

RESUMO

Background and Objective: The incidence and mortality of pancreatic cancer (PC) have increased in recent years. The current status of PC diagnosis and treatment remains grim in clinical practice because the commonly used early screening tools are not sufficient. Improving the early detection of PC and strengthening standardized comprehensive treatment remain the focus of PC research. Many studies have shown that micro RNAs (miRNAs) play an important role in the occurrence, development, and treatment of PC. It is expected that miRNAs will become new molecular markers of PC. Methods: We extracted and compiled useful information from the PubMed database that met our criteria for analyzing PC diagnosis, treatment, and prognosis. Key Content and Findings: In this narrative review, we summarize the mechanism of some miRNAs in the occurrence and development of PC and review them as potential markers for the diagnosis, treatment, and prognosis of PC. The function of miRNAs in PC has great potential in studying the pathogenesis of PC. The discovery of many important oncogenic miRNAs and their downstream targets will bring new ideas and research paths for the diagnosis and targeted therapy of PC. Conclusions: MiRNAs are expected to provide novel ideas and research directions for the diagnosis and targeted treatment of PC. However, more patient data and clinical trials are needed before miRNAs can become novel molecular markers for PC.

3.
Front Oncol ; 12: 960056, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936738

RESUMO

Background and Objectives: Pancreatic cancer (PC) is one of the deadliest cancers worldwide although substantial advancement has been made in its comprehensive treatment. The development of artificial intelligence (AI) technology has allowed its clinical applications to expand remarkably in recent years. Diverse methods and algorithms are employed by AI to extrapolate new data from clinical records to aid in the treatment of PC. In this review, we will summarize AI's use in several aspects of PC diagnosis and therapy, as well as its limits and potential future research avenues. Methods: We examine the most recent research on the use of AI in PC. The articles are categorized and examined according to the medical task of their algorithm. Two search engines, PubMed and Google Scholar, were used to screen the articles. Results: Overall, 66 papers published in 2001 and after were selected. Of the four medical tasks (risk assessment, diagnosis, treatment, and prognosis prediction), diagnosis was the most frequently researched, and retrospective single-center studies were the most prevalent. We found that the different medical tasks and algorithms included in the reviewed studies caused the performance of their models to vary greatly. Deep learning algorithms, on the other hand, produced excellent results in all of the subdivisions studied. Conclusions: AI is a promising tool for helping PC patients and may contribute to improved patient outcomes. The integration of humans and AI in clinical medicine is still in its infancy and requires the in-depth cooperation of multidisciplinary personnel.

4.
Front Oncol ; 12: 903484, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35957917

RESUMO

Objective: To explore the effects of the expression level of miR-520-5p/PPP5C in pancreatic cancer cells and exosomes on cell viability, angiogenesis, autophagy, which involved in the mechanism of gemcitabine resistance in pancreatic cancer. Methods: APSC-1 cell line was treated with gemcitabine, after which its exosomes were extracted for NTA assay. Subsequently, the drug resistance of APSC-1 cells was assayed using CCK8, as well as the activity of HUVEC cells treated with exosomes from each group of APSC-1 cells after drug resistance treatment as well as overexpression treatment. Five groups of HUVEC cells treated with exosomes were subjected to in vitro tubule formation assay. levels of PPP5C in each group of ASPC-1 cells and their exosomes, levels of overexpressed PPP5C, and related exosomal proteins were examined by WB. mRNA expression levels of PPP5C and levels of miR-520a were examined by qPCR The relationship between miR-520a-5p and PPP5C was investigated. After that, the autophagy of PPP5C was detected. Finally, it was analyzed by TCGA database for survival prognosis analysis. Results: APSC-1 cells had an IC50 value of 227.1 µM for gemcitabine, elevated PPP5C expression, drug resistance, and enhanced HUVEC cell activity; exosomes CD9, CD63, and CD81 were significantly expressed in all groups; meanwhile, enhanced PPP5C expression not only promoted in vitro tubule formation but also increased autophagy levels; meanwhile, its relationship with miR-520-5p and There was a targeted inhibitory relationship between its level and miR-520-5p and PPP5C, and its elevated level also led to a decrease in the survival level of patients over 3-5 years. Conclusion: PPP5C has a prognostic role in pancreatic cancer by promoting the value-added and invasion of pancreatic cancer cells, and a targeted inhibitory relationship between miR-520-5p and PPP5C was found.

5.
Chem Sci ; 14(1): 136-142, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36605736

RESUMO

Nonlinear optical (NLO) crystals featuring a strong second-harmonic generation (SHG) response and suitable birefringence to achieve phase-matching are in urgent demand in industrial and commercial applications. Based on the substitution strategy, two new NLO lead-iodide formates, K2[PbI2(HCOO)2] and Rb2[PbI2(HCOO)2], have been successfully synthesized using a moderate mixed-solvothermal method. K2[PbI2(HCOO)2] and Rb2[PbI2(HCOO)2] exhibit strong phase-matching SHG responses of 8 and 6.8 × KDP, respectively, a suitable birefringence and transparent window covering most of the visible light and mid-IR region. Crystal structures and theoretical calculations unveil that the origins of the strong SHG response and suitable birefringence can be credibly attributed to the oriented arrangement of the highly distorted [PbI2O4] hexa-coordinated polyhedra, which are consistent in their local dipole moments, as well. This research provides a new strategy to explore high-performance NLO crystals.

6.
Int J Comput Assist Radiol Surg ; 17(3): 569-578, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34606060

RESUMO

PURPOSE: Precise segmentation of intestinal wall vessels is vital to colonic perforation prevention. However, there are interferences such as gastric juice in the vessel image of the intestinal wall, especially vessels and the mucosal folds are difficult to distinguish, which easily lead to mis-segmentation. In addition, the insufficient feature extraction of intricate vessel structures may leave out information of tiny vessels that result in rupture. To overcome these challenges, an effective network is proposed for segmentation of intestinal wall vessels. METHODS: A global context attention network (GCA-Net) that employs a multi-scale fusion attention (MFA) module is proposed to adaptively integrate local and global context information to improve the distinguishability of mucosal folds and vessels, more importantly, the ability to capture tiny vessels. Also, a parallel decoder is used to introduce a contour loss function to solve the blurry and noisy blood vessel boundaries. RESULTS: Extensive experimental results demonstrate the superiority of the GCA-Net, with accuracy of 94.84%, specificity of 97.89%, F1-score of 73.80%, AUC of 96.30%, and MeanIOU of 76.46% in fivefold cross-validation, exceeding the comparison methods. In addition, the public dataset DRIVE is used to verify the potential of GCA-Net in retinal vessel image segmentation. CONCLUSION: A novel network for segmentation of intestinal wall vessels is developed, which can suppress interferences in intestinal wall vessel images, improve the discernibility of blood vessels and mucosal folds, enhance vessel boundaries, and capture tiny vessels. Comprehensive experiments prove that the proposed GCA-Net can accurately segment the intestinal wall vessels.


Assuntos
Processamento de Imagem Assistida por Computador , Vasos Retinianos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Intestinos
7.
Inorg Chem ; 61(2): 1130-1135, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34964612

RESUMO

Nonlinear optical (NLO) materials are playing an increasingly vital role in laser science and technology. Herein, we report a new lead formate, KCs2Pb2(HCOO)2Cl5, successfully synthesized by using mild mix-solvothermal methods. By the anionic substitution of a [CH3COO] group with a [HCOO] group, the dipole moment of the distorted [PbCl4O2] polyhedron is increased. In contrast, polarization from the anionic group and the volume of the unit cell are reduced. Hence, KCs2Pb2(HCOO)2Cl5 possesses a strong second-harmonic-generation (SHG) response of 4.2 times that of KH2PO4 (KDP), a transparent window covering 0.43-1.87 µm, a large band gap of 3.52 eV, and moderate birefringence (0.11@1064 nm). Systematic theoretical calculations illustrate the origin of the linear and nonlinear optical properties of KCs2Pb2(HCOO)2Cl5. This research provides a viable strategy for the design and synthesis of new NLO crystals.

8.
Chemistry ; 28(4): e202103687, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34651354

RESUMO

Nonlinear optical (NLO) crystals are widely applied in information technology, micro-manufacturing and medical treatment. Herein, a new lead mixed halide with strong second-harmonic generation (SHG) response, Cs3 Pb2 (CH3 COO)2 Br3 I2 , has been designed and rationally synthesized. Cs3 Pb2 (CH3 COO)2 Br3 I2 represents the rare NLO crystal featuring that three different anions (I- , Br- and O2- ) simultaneously coordinate the Pb(II) atom to form a severely distorted [PbBr2 I2 O2 ] polyhedron with a large polarizability. Remarkably, Cs3 Pb2 (CH3 COO)2 Br3 I2 not only exhibits a very strong phase-matching SHG response of 9×KH2 PO4 (KDP), but also possesses a large birefringence (0.27@1064 nm) and high laser damage threshold (LDT). The strong SHG effect of Cs3 Pb2 (CH3 COO)2 Br3 I2 mainly originates from the oriented arrangement of [Pb2 Br3 I2 ] chains. This study points out an effective strategy to develop new NLO crystals with strong SHG response.

9.
Inorg Chem ; 60(22): 17364-17370, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34710323

RESUMO

The unity of structure-property design and practical synthesis is a key to develop nonlinear optical (NLO) materials. However, many designed structures are hard to get because of the incapability of controlling the arrangement of structural motifs. After careful synthesis, we successfully obtained a new NLO crystal with expected properties, KWO3F, which features a long-range anion-ordered while directed parallel arrangement of [WO5F] d0 transition metal fluorooxo-functional (d0 [TMOF]) motifs. This arrangement is vital to achieve a strong second-harmonic generation (SHG) response, which is proved by dipole moment analyses and theoretical calculations. Remarkably, KWO3F possesses a strong phase-matching SHG response (3 × KDP), high thermal stability (stable up to 350 °C in air), a large laser damage threshold (LDT, 129.7 MW/cm2), a wide transparent window (0.5-10 µm), and a suitable birefringence (0.088 @ 1064 nm). Our research demonstrated that the introduction of the NLO-active d0 [TMOF] motif is an effective strategy to design new potential NLO materials.

10.
Bioengineered ; 12(1): 6484-6498, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34517785

RESUMO

To explore mechanism of intestinal flora dysregulation promoting constipation, 60 specific pathogen-free (SPF) mice were used as research objects and were treated with constipation population fecal fluid gavage and distilled water gavage. Then, relationship between intestinal dysregulation and constipation in mice with biofilm-mediated intestinal flora was investigated in vitro. The results showed that recombinant serotonin transporter (SERT) messenger ribonucleic acid (mRNA) level of the constipation population fecal fluid gavage group and the relative expression level of SERT mRNA were 1.61 ± 0.08 and 1.49 ± 0.06, which were higher markedly than those of distilled water group (P < 0.05). The level of 5-hydroxytryptamine (5-HT) in colonic tissue of the constipation population fecal fluid gavage group was 145.36 ± 14.12 ng/mL, and the expression level of 5-HT on the surface of epithelial cells of biofilm-positive colonic tissue was 20.11 ± 2.03, which were significantly lower than those of the distilled water group, with statistical significance (P < 0.05). Besides, the microbial sequencing of fecal flora indicated that The Akk and bacteroidetes ofconstipation population fecal fluid gavage group were higher hugely than those of distilled water group (P < 0.05).In conclusion, after the occurrence of constipation, the diversity of intestinal microflora decreased, and the probiotics reduced. Iintestinal microflora dysregulation would lead to increase of SERT expression level in defecation function and intestinal motility in mice, and the decrease of 5-HT, thereby changing the intestinal movement resulting in mucosal protective barrier damage,thereby causing changes in intestinal movement and the destruction of the intestinal mucosal protective barrier, which eventually resulted in constipation. The occurrence of constipation could be improved by regulating balance of intestinal flora, increasing the diversity of flora, and reducing the genus of opportunistic pathogens.


Assuntos
Constipação Intestinal , Disbiose , Microbioma Gastrointestinal/fisiologia , Animais , Biofilmes , Constipação Intestinal/microbiologia , Constipação Intestinal/fisiopatologia , Disbiose/microbiologia , Disbiose/fisiopatologia , Fezes/microbiologia , Feminino , Mucosa Intestinal/fisiopatologia , Masculino , Camundongos , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo
11.
Chemistry ; 27(51): 12976-12980, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34258801

RESUMO

The discovery of new nonlinear optical (NLO) crystals with excellent properties is in urgently demand because of their ability to generate coherent light. Herein, we report an unique NLO lead bromide formate, KCs2 [Pb2 Br5 (HCOO)2 ], which has been synthesized by a mix-solvothermal method. KCs2 [Pb2 Br5 (HCOO)2 ] exhibits strong phase-matching second-harmonic generation (SHG) response (6.5×KDP), large birefringence (0.16@ 1064 nm), and a wide transparent window in most visible light and mid-IR region. Interestingly, KCs2 [Pb2 Br5 (HCOO)2 ] features a polar 3D lead-bromide framework in which adjacent Pb-Br layers containing coplanar Pb6 Br6 rings are not only parallel to each other, but also orient in the same direction. These oriented arrangements are responsible for the strong SHG response and large birefringence that are elucidated by both local dipole moment and theoretical calculations. This research provides a new strategy to explore subsequent NLO crystals.

12.
Inorg Chem ; 60(7): 5290-5296, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33729802

RESUMO

The substitution of alkali metal cation or halogen anion based on nonlinear crystals is an effective strategy to exploit new optical materials. The strategy has been successfully expanded to discover two new lead halides, Rb3Pb2(CH3COO)2X5 (X = Br, Cl). The substitution of the Cs+ cation with a Rb+ cation can not only increase the local dipole moment of the distorted [PbBr4O2] polyhedron but also reduce the cell unit, resulting in a large net macroscopic polarization. Therefore, Rb3Pb2(CH3COO)2Br5 possesses a strong second-harmonic generation (SHG) response (6 × KDP) and a large birefringence (0.18@1064 nm). Furthermore, by the substitution of the Br- anion with a Cl- anion, Rb3Pb2(CH3COO)2Cl5 exhibits a high laser damage threshold (LDT, 84 × AgGaS2) and a short UV cutoff edge of 287 nm, as well as moderate SHG response (3 × KDP) and birefringence (0.11@1064 nm). Detailed theory calculations elucidate the origin of the linear and nonlinear optical properties of these compounds.

13.
Inorg Chem ; 60(8): 5821-5828, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33779158

RESUMO

Nonlinear-optical (NLO) crystal is an important photoelectric functional material. In this work, a new NLO titanium iodate, (H3O)2Ti(IO3)6, along with Ti(IO3)4 has been synthesized under facile conditions. The space group of (H3O)2Ti(IO3)6 is the chiral noncentrosymmetric group R3 (No. 146), with an interesting three-dimensional framework, while that of Ti(IO3)4 is the centrosymmetric space group P1̅ (No. 2) containing one-dimensional chains. Thermogravimetric analysis shows that (H3O)2Ti(IO3)6 and Ti(IO3)4 have no weight loss below 220 and 390 °C, respectively. In addition, (H3O)2Ti(IO3)6 not only is thermally stable up to 200 °C in an air atmosphere but also is stable in water. (H3O)2Ti(IO3)6 has a moderate-intensity second-harmonic-generation (SHG) response (1.4×KDP), a large laser-induced damage threshold (46×AgGaS2), and high transmittance in the wavelength ranges of 0.5-1.4 and 2.5-10 µm. Both local dipole moment and systematic theoretical calculations reveal that the SHG response of (H3O)2Ti(IO3)6 is mainly because of the combined effect of [TiO6] octahedra and IO3 and IO4 units. In a word, (H3O)2Ti(IO3)6 exhibits good NLO performances, as well as water resistance and facile growth of a single crystal with high quality, indicating its potential application as NLO materials in the visible and mid-IR regions, especially the visible region.

14.
Angew Chem Int Ed Engl ; 60(4): 2116-2119, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33058514

RESUMO

Nonlinear optical (NLO) crystals are the key component in solid-state lasers. New second-harmonic generation (SHG) effective halides, Cs3 Pb2 (CH3 COO)2 X5 (X=I, Br), have been rationally synthesized by introducing acetate groups into lead halide perovskites under moderate solvothermal conditions. Cs3 Pb2 (CH3 COO)2 X5 (X=I, Br) feature highly oriented anionic chains constructed by distorted [PbX4 O2 ] (X=I, Br) polyhedrons. Both the theoretical studies and the dipole moment calculations uncover that their SHG effects are mainly originated from the distorted [PbX4 O2 ] (X=I, Br) polyhedrons. Remarkably, Cs3 Pb2 (CH3 COO)2 I5 exhibits strong phase-matching SHG response (8×KDP) and large birefringence (0.26@ 1064 nm). Moreover, Cs3 Pb2 (CH3 COO)2 X5 (X=I, Br) also possess high laser damage threshold (LDT) which are almost 27 and 41 times that of AgGaS2 , respectively.

15.
Dalton Trans ; 49(12): 3672-3675, 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-31657402

RESUMO

Two new isostructural non-centrosymmetric cerium iodates KxCe9(IO3)36 (x≈ 3) and LaxCe9(IO3)36 (x≈ 0.3) were synthesized via a hydrothermal method and systematically characterized. They are intermediate valence compounds with the same band gap, showing similar microscopic net dipole moments per unit volume, but different macroscopic second-harmonic generation (SHG) responses under 1064 nm laser irradiation. This research gives a new view for understanding the effects of electronic structure on the SHG response.

16.
Angew Chem Int Ed Engl ; 58(12): 3824-3828, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30663839

RESUMO

A novel niobium oxyiodate sulfate, Nb2 O3 (IO3 )2 (SO4 ), was fabricated by a rational multi-component design under moderate hydrothermal conditions. This multi-component design is inspired by an interesting niobium oxysulfate reaction, which opens a new door for synthetic method to effectively introduce refractory metals such as Nb into crystal structures by hydrothermal synthesis. Nb2 O3 (IO3 )2 (SO4 ) features a cube-like topological structure with a large phase-matching second harmonic generation (SHG) response (6×KDP), a wide transparency window (0.38-8 µm), and a high laser damage threshold (LDT) (20×AgGaS2 ). It has the highest thermostability (stable up to 580 °C under air) among reported non-centrosymmetric (NCS) iodates and sulfates and is stable in water and even concentrated H2 SO4 . Furthermore, Nb2 O3 (IO3 )2 (SO4 ) is a unique nonlinear optical (NLO) material among iodates and sulfates, because its SHG effect is mainly caused by the MO6 units rather than the IO3 or SO4 units, which is demonstrated by density functional theory (DFT) calculations.

17.
Inorg Chem ; 56(11): 6275-6280, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28537718

RESUMO

Enantioseparation is an integral process in the pharmaceutical industry, considering the ever-increasing demand for chiral medicine products. As a new material, porous metal-organic frameworks (MOFs) have shown their potential application in this field because their structures are easy to adjust and control. Though chiral recognition between racemic substrates and frameworks has made preliminary progress, discussions of their size-matching effects are rare. Herein with the help of channel-tunable homochiral MOFs (HMOFs), diols of different sizes have been separated in good enantiomeric excess (ee%). In addition, the ee% reaches 67.4% for the first time for diols as large as 1,1,2-triphenyl-1,2-ethanediol, which turns out to be the most effective value so far.


Assuntos
Álcoois/química , Estruturas Metalorgânicas/química , Estrutura Molecular , Tamanho da Partícula , Porosidade , Estereoisomerismo , Propriedades de Superfície
18.
Chemistry ; 22(13): 4460-8, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26864609

RESUMO

A new mixed-ligand metal-organic framework (MOF), ZnATZ-BTB, has been constructed as a luminescent ratiometric thermometer by making use of the intrinsic dual emission at cryogenic temperatures. Its twofold interpenetrated network promotes the Dexter energy transfer (DET) between the mixed organic lumophores. The temperature-dependent luminescent behavior arises from the thermal equilibrium between two separated excited states coupled by DET, which is confirmed by Boltzmann distribution fitting. The small excited-state energy gap allows ZnATZ-BTB to measure and visualize cryogenic temperatures (30-130 K) with significantly high relative sensitivity (up to 5.29% K(-1) at 30 K). Moreover, it is the first example of a ratiometric MOF thermometer the dual emitting sources of which are widely applicable mixed organic ligands, opening up new opportunities for designing such devices.

19.
Inorg Chem ; 52(21): 12305-7, 2013 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-24131207

RESUMO

Complex 1 exhibits the crownlike structure with the unprecedented 12-membered ring system, while in 2, a cagelike cluster has been connected with two distorted cores in nickel thiolates. The synthesis of novel clusters by way of C-S bond cleavage was first reported in the field of nickel thiolates.

20.
Inorg Chem ; 50(16): 7618-24, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21744812

RESUMO

Three novel coordination polymers, [Cd(5)(HTTHA)(2)(Hpt)(4)(H(2)O)]·4H(2)O (1; H(6)TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetic acid, Hpt = pyridinium-4-thiolate), {[Cd(3)(TTHA)(dps)(H(2)O)(3)](2)}·H(2)O (2), and [Zn(3)(TTHA)(dps)(H(2)O)]·5H(2)O (3; dps =4,4'-dipyridylsulfide), have been synthesized by the flexible hexapodal acid H(6)TTHA and in-situ-generated Hpt and dps ligands from a 4,4'-dipyridyldisulfide (dpds) precursor through cleavage of both S-S and S-C(sp(2)) bonds and temperature-dependent chemical rearrangement under hydrothermal conditions. Polymers 2 and 3 exhibit 3D frameworks, while in 1, the extended 3D network can be described as 2D layers further bridged via H-bond interaction. Intriguingly, the three compounds have shown an unusual luminescence thermochromism. Upon decreasing the temperature from 298 to 10 K, the emission bands grow in intensity and change in color dramatically.

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