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1.
Eur J Immunol ; 54(4): e2350800, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38282083

ABSTRACT

Obesity-induced adipose tissue inflammation plays a critical role in the development of metabolic diseases. For example, NK1.1+ group 1 innate lymphoid cells (G1-ILCs) in adipose tissues are activated in the early stages of inflammation in response to a high-fat diet (HFD). In this study, we examined whether the composition of fatty acids affected adipose inflammatory responses induced by an HFD. Mice were fed a stearic acid (C18:0)-rich HFD (HFD-S) or a linoleic acid (C18:2)-rich HFD (HFD-L). HFD-L-fed mice showed significant obesity compared with HFD-S-fed mice. Visceral and subcutaneous fat pads were enlarged and contained more NK1.1+KLRG1+ cells, indicating that G1-ILCs were activated in HFD-L-fed mice. We examined early changes in adipose tissues during the first week of HFD intake, and found that mice fed HFD-L showed increased levels of NK1.1+CD11b+KLRG1+ cells in adipose tissues. In adipose tissue culture, addition of 4-hydroxynonenal, the most frequent product of lipid peroxidation derived from unsaturated fatty acids, induced NK1.1+CD11b+CD27- cells. We found that calreticulin, a ligand for the NK activating receptor, was induced on the surface of adipocytes after exposure to 4-hydroxynonenal or a 1-week feeding with HFD-L. Thus, excess fatty acid intake and the activation of G1-ILCs initiate and/or modify adipose inflammation.


Subject(s)
Aldehydes , Diet, High-Fat , Fatty Acids , Animals , Mice , Adipocytes , Adipose Tissue , Calreticulin/metabolism , Diet, High-Fat/adverse effects , Fatty Acids/metabolism , Immunity, Innate , Inflammation/metabolism , Lymphocytes/metabolism , Obesity
2.
Sci Technol Adv Mater ; 25(1): 2334667, 2024.
Article in English | MEDLINE | ID: mdl-38628979

ABSTRACT

Many artificial molecular machines have been synthesized, and various functions have been expressed by changing their molecular conformations. However, their structures are still simple compared with those of biomolecular machines, and more energy is required to control them. To design artificial molecular machines with more complex structures and higher functionality, it is necessary to combine molecular machines with simple movements such as components. This means that the motion of individual molecular machines must be precisely controlled and observed in various environments. At the air - water interface, the molecular orientation and conformation can be controlled with little energy as thermal fluctuations. We designed various molecular machines and controlled them using mechanical stimuli at the air - water interface. We also controlled the transfer of forces to the molecular machines in various lipid matrices. In this review, we describe molecular pliers with amphiphilic binaphthyl, molecular paddles with binuclear platinum complexes, and molecular rotors with julolidine and BODIPY that exhibit twisted intramolecular charge transfer.


This review discusses the dependence of the behaviour of molecular machines around their environment through the mechanically control of simple molecular machines at the air ­ water interface.

3.
Hepatology ; 76(1): 112-125, 2022 07.
Article in English | MEDLINE | ID: mdl-34855990

ABSTRACT

BACKGROUND AND AIMS: Chronic liver congestion reflecting right-sided heart failure (RHF), Budd-Chiari syndrome, or Fontan-associated liver disease (FALD) is involved in liver fibrosis and HCC. However, molecular mechanisms of fibrosis and HCC in chronic liver congestion remain poorly understood. APPROACH AND RESULTS: Here, we first demonstrated that chronic liver congestion promoted HCC and metastatic liver tumor growth using murine model of chronic liver congestion by partial inferior vena cava ligation (pIVCL). As the initial step triggering HCC promotion and fibrosis, gut-derived lipopolysaccharide (LPS) appeared to induce LSECs capillarization in mice and in vitro. LSEC capillarization was also confirmed in patients with FALD. Mitogenic factor, sphingosine-1-phosphate (S1P), was increased in congestive liver and expression of sphingosine kinase 1, a major synthetase of S1P, was increased in capillarized LSECs after pIVCL. Inhibition of S1P receptor (S1PR) 1 (Ex26) and S1PR2 (JTE013) mitigated HCC development and liver fibrosis, respectively. Antimicrobial treatment lowered portal blood LPS concentration, LSEC capillarization, and liver S1P concentration accompanied by reduction of HCC development and fibrosis in the congestive liver. CONCLUSIONS: In conclusion, chronic liver congestion promotes HCC development and liver fibrosis by S1P production from LPS-induced capillarized LSECs. Careful treatment of both RHF and liver cancer might be necessary for patients with RHF with primary or metastatic liver cancer.


Subject(s)
Carcinoma, Hepatocellular , Heart Failure , Liver Neoplasms , Vascular Diseases , Animals , Carcinoma, Hepatocellular/pathology , Disease Models, Animal , Fibrosis , Humans , Lipopolysaccharides , Liver Cirrhosis/pathology , Liver Neoplasms/pathology , Lysophospholipids/metabolism , Mice , Receptors, Lysosphingolipid/metabolism , Sphingosine/analogs & derivatives , Sphingosine/metabolism
4.
Liver Int ; 43(6): 1213-1224, 2023 06.
Article in English | MEDLINE | ID: mdl-37029645

ABSTRACT

BACKGROUNDS AND AIMS: Toll-like receptor (TLR) agonists have been developed as adjuvants to efficiently induce antiviral immune responses. Specificity and potency of these compounds are essential requirements for clinical trial applications. In patients with hepatitis B virus (HBV) infections, sustained loss of hepatitis B surface antigen (HBsAg) is a therapeutic goal, which may be achievable by the sequential activation of follicular helper T cells (Tfh) and antibody-secreting B cells. We aimed to elucidate whether novel TLR7 agonist, GS-986, could activate immune responses involved in HBV elimination. METHODS: To clarify the impact of GS-986 on pDCs, we quantified the expression levels of surface markers and evaluated for Tfh induction in a culture model consisting of human pDCs with allogeneic naïve CD4+ T cells. In addition, we examined whether GS-986 could enhance HBs antibody production capacity using PBMC from CHB patients. RESULTS: pDCs from CHB patients had lower OX40L expression and as well as impaired capacity for Tfh induction compared with those from healthy donors. However, GS-986-stimulated pDCs from CHB patients expressed OX40L and produced IL-6 and IL-12, resulting in the induction of IL-21-producing Tfh cells (CXCR5+ PD-1+ CD4+ ) from naïve CD4+ T cells. The Tfh-inducing capacity of GS-986 was reduced in the presence of an anti-OX40L blocking antibody. Furthermore, GS-986 promoted HBsAg-specific antibody production in PBMCs from CHB patients. CONCLUSIONS: GS-986 is an adjuvant that stimulates pDCs to induce Tfh differentiation and antigen-specific B-cell production. This immune profile may be beneficial for therapeutic application as an immune modulator in CHB patients.


Subject(s)
Antiviral Agents , Hepatitis B, Chronic , Toll-Like Receptor 7 , Hepatitis B, Chronic/drug therapy , Humans , Toll-Like Receptor 7/agonists , Antiviral Agents/therapeutic use , Male , Female , Middle Aged , Up-Regulation , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/drug effects , Cell Differentiation , Dendritic Cells/drug effects , Dendritic Cells/metabolism , T Follicular Helper Cells/cytology , T Follicular Helper Cells/drug effects , Hepatitis B Surface Antigens/metabolism , Antibodies, Viral/metabolism
5.
Hepatol Res ; 53(7): 618-628, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36905232

ABSTRACT

BACKGROUND: The antidiabetic drugs sodium glucose cotransporter 2 inhibitors (SGLT2is) and thiazolidinediones have beneficial effects on the liver dysfunction of patients with nonalcoholic fatty liver disease and type 2 diabetes mellitus (T2DM). We aimed to determine the efficacy of these drugs for the treatment of liver disease in patients with metabolic dysfunction-associated fatty liver disease (MAFLD) and T2DM. METHODS: We undertook a retrospective study of 568 patients with MAFLD and T2DM. Of these, 210 were treating their T2DM with SGLT2is (n = 95), 86 with pioglitazone (PIO), and 29 with both. The primary outcome was the change in Fibrosis-4 (FIB-4) index between baseline and 96 weeks. RESULTS: At 96 weeks, the mean FIB-4 index had significantly decreased (from 1.79 ± 1.10-1.56 ± 0.75) in the SGLT2i group, but not in the PIO group. The aspartate aminotransferase to platelet ratio index, serum aspartate and alanine aminotransferase (ALT), hemoglobin A1c, and fasting blood sugar significantly decreased in both groups (ALT: SGLT2i group, -17 ± 3 IU/L; PIO group, -14 ± 3 IU/L). The bodyweight of the SGLT2i group decreased, but that of the PIO group increased (-3.2 kg and +1.7 kg, respectively). When the participants were allocated to two groups according to their baseline ALT (>30 IU/L), FIB-4 index significantly decreased in both groups. In patients taking pioglitazone, the addition of SGLT2i improved liver enzymes but not FIB-4 index for 96 weeks. CONCLUSIONS: Treatment with SGLT2i causes a larger improvement in FIB-4 index than PIO in patients with MAFLD over 96 weeks.

6.
Hepatol Res ; 53(4): 370-376, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36461886

ABSTRACT

AIM: Congestive hepatopathy often leads to liver fibrosis and hepatocellular carcinoma. Imaging modalities provided clinical evidence that elevation of liver stiffness and tumor occurrence are mainly induced in the periphery of the liver in patients with congestive hepatopathy. However, clinical relevance of liver stiffness and liver fibrosis is unclear because liver congestion itself increases liver stiffness in congestive hepatopathy. It also unclear which factors configure such regional disparity of tumor development in patients with congestive hepatopathy. To answer these questions, we evaluated the macroscopic spatial distribution of liver fibrosis and tumors in the murine model of congestive hepatopathy. METHODS: Chronic liver congestion was induced by partial ligation of the suprahepatic inferior vena cava. Distribution of liver congestion, fibrosis, and tumors in partial ligation of the suprahepatic inferior vena cava mice were assessed by histological findings, laser microdissection (LMD)-based qPCR and enhanced computed tomography. LMD-based RNA-sequencing was performed to identify causal factors that promote tumor development in congestive hepatopathy. RESULTS: Liver fibrosis was mainly induced in the periphery of the liver and co-localized with distribution of liver congestion. Liver tumors were also induced in the periphery of the liver where liver congestion and fibrosis occurred. LMD-based RNA-sequencing revealed the upregulation of extracellular matrix/collagen fibril-, wound healing-, angiogenesis-, morphogenesis-, and cell motility-related signaling pathways in periphery of liver compared with liver center. CONCLUSIONS: Our findings showed the experimental relevance of liver congestion, fibrosis, and tumor development in congestive hepatopathy, and may provide important locational information. Macroscopic regional disparity observed in this murine model should be considered to manage patients with congestive hepatopathy.

7.
Langmuir ; 38(20): 6481-6490, 2022 05 24.
Article in English | MEDLINE | ID: mdl-35549351

ABSTRACT

An air-water interface enables molecular assemblies and conformations to be controlled according to their intrinsic interactions and anisotropic stimuli. The chirality and conformation of binaphthyl derivatives have been controlled by tuning molecular aggregated states in solution. In this study, we have tuned molecular aggregated states of monobinaphthyldurene (MBD) by applying different mechanical stimuli to control the conformation at the air-water interface. Density functional theory calculations indicate that MBD exists essentially in two conformations, namely, 1-MBD (most stable) and 2-MBD (less stable). MBD was mechanically dissolved in appropriate lipid matrices using the Langmuir-Blodgett (LB) method, while pure MBD was self-assembled at the dynamic air-water interface in the absence of or by applying vortex motions (vortex LB method). In MBD mixed monolayer, surface pressure-molecular area measurements and atomic force microscopy observations suggest that separate lipids and MBD phases transform to mixed phases induced by the dissolution of MBD into the lipid matrices during mechanical compression at the air-water interface. Circular dichroism measurements indicate that molecular conformation changes from 1-MBD to 2-MBD in passing from a separated phase to a mixed MBD/lipid phase. In addition, the molecular aggregated states and conformations of MBD depend on the spreading volume and vortex flow rate when applying the vortex LB method. Molecular conformations and aggregated states of MBD could be controlled continuously by applying a mechanical stimulus at the air-water interface.


Subject(s)
Lipids , Water , Circular Dichroism , Microscopy, Atomic Force , Molecular Conformation , Surface Properties
8.
Langmuir ; 38(17): 5237-5247, 2022 May 03.
Article in English | MEDLINE | ID: mdl-34873909

ABSTRACT

In this study, we advanced the conventional Langmuir-Blodgett (LB) method to a high-temperature range (above 100 °C) using a newly manufactured LB machine, which is adaptable to a high-boiling-point subphase, as a universally usable apparatus. A sophisticated trough design, with homogeneous heating capability up to approximately 200 °C, together with automatic film compression and Langmuir-Schaefer type film transfer, enabled the fabrication of highly aligned thin films of polymeric semiconductors with uniaxial alignment of polymer backbones, which is desirable for efficient charge transport. Herein, ultrathin films of semicrystalline thiophene-based semiconductors were prepared on ethylene glycol and heated to 80 °C. The analyses of the transferred films with pressure-area isotherms, atomic force microscopy (AFM), polarized optical microscopy (POM), and grazing-incidence wide-angle X-ray scattering (GIWAXS) indicated that the proposed high-temperature LB method allows ideal deposition of high-quality ultrathin films with molecular layer precision at the selected high-temperature conditions. Furthermore, preparing thin-film donor-acceptor-type copolymers in ionic liquids at high temperatures (up to 140 °C) was a challenging task that was successfully demonstrated in this study. Highly ordered thin films of donor-acceptor polymers with a uniaxial backbone orientation were obtained only at 140 °C. The obtained semicrystalline thin films with uniaxially aligned polymer backbones significantly contribute to the two-dimensional overlap of molecular orbitals, which is likely to promote charge transport. The use of the manufactured automatic LB machines is advantageous for better quality films prepared at higher temperatures (even above 100 °C) from various technical viewpoints, including homogeneous heating, constant compression, and automatic film transfer. The novel methodology proposed herein expands the possibilities of the Hyper 100 °C Langmuir-Blodgett technique, which has not been accessible by the conventional LB method with the aqueous subphase.

9.
J Infect Dis ; 223(12): 2080-2089, 2021 06 15.
Article in English | MEDLINE | ID: mdl-33073291

ABSTRACT

BACKGROUND: Hepatitis B surface antigen (HBsAg) loss is an ideal goal for chronic hepatitis B patients. Antiretroviral therapy (ART) in hepatitis B virus/human immunodeficiency virus-1 (HBV/HIV-1)-coinfected patients can lead to hepatic flare (HF) caused by immune reconstitution-induced inflammatory syndrome (IRIS). Here, we investigated the impact of IRIS-HF on HBsAg loss. METHODS: This was a retrospective study of 58 HBV/HIV-1-coinfected subjects HBsAg-positive for ≥6 months before ART initiation and followed for ≥1 year (median 9.9 years) after ART initiation. We examined humoral factors in sera from healthy volunteers, HIV-monoinfected patients, and HBV/HIV-1-coinfected patients with IRIS-HF or acute hepatitis B infection. RESULTS: During ART, HBsAg loss was observed in 20 of 58 HBV/HIV-1-coinfected patients (34.5%). Of the 58 patients, 15 (25.9%) developed IRIS-HF within 12 months of ART initiation. HBsAg loss was more frequent among patients who developed IRIS-HF (11/15, 73.3%) than those who did not (9/43, 20.9%). Multivariate analysis showed IRIS-HF was an independent predictor of subsequent HBsAg loss. Younger age and higher baseline HBV DNA titer were associated with IRIS-HF. Elevation of sCD163, not CXCL9, CXC10, CXCXL11, or CXCL13, was observed at IRIS-HF. CONCLUSIONS: IRIS-HF was associated with HBsAg loss in HBV/HIV-1-coinfected patients.


Subject(s)
Anti-HIV Agents , Coinfection , HIV Infections , Hepatitis B, Chronic , Immune Reconstitution Inflammatory Syndrome , Anti-HIV Agents/therapeutic use , Coinfection/immunology , Coinfection/virology , DNA, Viral , HIV Infections/complications , HIV Infections/drug therapy , HIV-1 , Hepatitis B Surface Antigens/blood , Hepatitis B virus/genetics , Hepatitis B, Chronic/complications , Humans , Retrospective Studies
10.
BMC Gastroenterol ; 21(1): 55, 2021 Feb 08.
Article in English | MEDLINE | ID: mdl-33557759

ABSTRACT

BACKGROUND: Pathological angiogenesis is involved in the development of hepatocellular carcinoma. In patients with chronic hepatitis C (CHC), the level of angiogenic factor angiopoietin (ANGP)-2 is reported to be increased in the blood, correlating with fibrosis. In this study, we aimed to clarify whether blood ANGP-2 is useful as a biomarker for liver angiogenesis and fibrosis in CHC patients and to further reveal the relationship between such pathology in a carbon tetrachloride (CCl4)-treated liver fibrosis mouse model. METHODS: Plasma levels of ANGP-2, expression of a liver sinusoidal endothelial cell (LSEC) marker (CD31), collagen deposition (Sirius Red staining) in the liver, clinical fibrosis markers (Mac-2 binding protein glycosylation isomer, virtual touch quantification, and liver stiffness measurement), and liver function (albumin bilirubin score) were examined in CHC patients. To determine the effects of an anti-angiogenic agent on liver fibrosis in vivo, sorafenib was administered to the CCl4-treated mice (BALB/c male). RESULTS: The plasma levels of ANGP-2 were increased in CHC patients compared to healthy volunteers and decreased by the eradication of hepatitis C with direct-acting antivirals. In addition, plasma ANGP-2 levels were correlated with CD31 expression, collagen deposition, clinical fibrosis markers, and liver function. Sorafenib inhibited liver angiogenesis and fibrosis in the CCl4-treated mice and was accompanied by decreased ANGP-2 expression in LSECs. CONCLUSIONS: ANGP-2 may serve as a useful biomarker for liver angiogenesis and fibrosis in CHC patients. In addition, angiogenesis and fibrosis may be closely related.


Subject(s)
Angiopoietin-2 , Hepatitis C, Chronic , Angiopoietin-2/therapeutic use , Animals , Antiviral Agents/therapeutic use , Carbon Tetrachloride , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/pathology , Humans , Liver/pathology , Liver Cirrhosis/pathology , Male , Mice , Mice, Inbred BALB C , Neovascularization, Pathologic
11.
Hepatol Res ; 51(7): 803-812, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33998102

ABSTRACT

AIM: In patients with liver cirrhosis, high levels of serum myostatin are associated with poor prognosis. We aimed to clarify the influence of myostatin on the prognosis of patients with non-alcoholic fatty liver disease-hepatocellular carcinoma (NAFLD-HCC) without cirrhosis and on the progression of liver fibrosis. METHODS: Serum myostatin levels were evaluated in 234 patients who underwent primary surgical resection for single HCC. To clarify the impact of myostatin on liver fibrosis, we established human primary liver fibroblasts from resected livers, and cultured them in the presence of myostatin. RESULTS: The median age was 67.4 years, the median L3 skeletal muscle mass index was 44.4 cm2 /m2 , and the median body mass index was 23.4 kg/m2 . Eighty-two (35.0%) patients had sarcopenia (L3 skeletal muscle mass index: men <42, women <38 cm2 /m2 ). The etiologies of liver disease were hepatitis B virus (n = 61), hepatitis C virus (n = 86), and non-B non-C hepatitis (n = 87) including NAFLD (n = 74). High preoperative serum myostatin and vascular invasion were independent predictors of poor overall survival (OS). High serum myostatin was associated with poor OS in patients with no sarcopenia (n = 152). In patients without advanced liver fibrosis (Fibrosis stage, 0-2; n = 58), high levels of serum myostatin were also associated with poor OS, regardless of sarcopenia. Serum myostatin levels were increased with the progression of liver fibrosis. Liver fibroblasts were activated and produced collagen following stimulation with myostatin. CONCLUSIONS: In patients with NAFLD-HCC without advanced liver fibrosis, high levels of serum myostatin were associated with poor OS. Myostatin activated primary fibroblasts and stimulated collagen production.

12.
Chemistry ; 26(29): 6461-6472, 2020 May 20.
Article in English | MEDLINE | ID: mdl-32159246

ABSTRACT

Soft and flexible two-dimensional (2D) systems, such as liquid interfaces, would have much more potentials in dynamic regulation on nano-macro connected functions. In this Minireview article, we focus especially on dynamic motional functions at liquid dynamic interfaces as 2D material systems. Several recent examples are selected to be explained for overviewing features and importance of dynamic soft interfaces in a wide range of action systems. The exemplified research systems are mainly classified into three categories: (i) control of microobjects with motional regulations; (ii) control of molecular machines with functions of target discrimination and optical outputs; (iii) control of living cells including molecular machine functions at cell membranes and cell/biomolecular behaviors at liquid interface. Sciences on soft 2D media with motional freedom and their nanoarchitectonics constructions will have increased importance in future technology in addition to popular rigid solid 2D materials.


Subject(s)
Nanostructures/chemistry , Nanotechnology/methods , Cell Tracking/methods , Motion , Pliability , Surface Properties
13.
Hepatol Res ; 50(4): 466-477, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31808236

ABSTRACT

AIM: Non-alcoholic fatty liver disease (NAFLD) is a leading cause of liver disease worldwide. Because liver fibrosis is associated with the long-term prognosis of patients with NAFLD, there is an urgent need for non-invasive markers of liver fibrosis. Sialic acid-binding immunoglobulin-like lectin-7 (Siglec-7) is an immunomodulatory molecule expressed on various immune cells, including macrophages, which plays a key role in liver inflammation and fibrosis in NAFLD. We aimed to determine whether serum levels of soluble Siglec-7 (sSiglec-7) could have utility at a marker of fibrosis in this patient population. METHODS: We examined serum samples from 93 NAFLD patients and 19 healthy donors for macrophage-associated protein, including sSiglec-7, soluble CD163, and YKL-40, and examined their correlation with liver fibrosis scores, tissue elastography, and histological findings. Independent factors associated with advanced fibrosis were analyzed using a logistic regression model and a decision tree. To clarify the source of sSiglec-7, we examined its expression in liver tissue-derived macrophages and cultured monocyte-derived macrophages. RESULTS: Serum sSiglec-7 levels were significantly higher in NAFLD patients compared with healthy donors, and correlated positively with sCD163 and YKL-40 levels. Serum sSiglec-7 was an independent diagnostic marker with high specificity (96.3%) for advanced fibrosis (F3 and F4) in NAFLD patients. Siglec-7 was mainly expressed on CCR2+ macrophages in the liver, and sSiglec-7 production by monocyte-derived macrophages in vitro was increased after stimulation by pro-inflammatory factors. CONCLUSIONS: Elevated serum sSiglec-7 could serve as an independent marker with high specificity for advanced liver fibrosis in patients with NAFLD.

14.
Macromol Rapid Commun ; 41(5): e1900585, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32009277

ABSTRACT

3D liquid crystal elastomer (3D-LCE) foams are used to support long-term neuronal cultures for over 60 days. Sequential imaging shows that cell density remains relatively constant throughout the culture period while the number of cells per observational area increases. In a subset of samples, retinoic acid is used to stimulate extensive neuritic outgrowth and maturation of proliferated neurons within the LCEs, inducing a threefold increase in length with cells displaying morphologies indicative of mature neurons. Designed LCEs' micro-channels have a similar diameter to endogenous parenchymal arterioles, ensuring that neurons throughout the construct have constant access to growth media during extended experiments. Here it is shown that 3D-LCEs provide a unique environment and simple method to longitudinally study spatial neuronal function, not possible in conventional culture environments, with simplistic integration into existing methodological pipelines.


Subject(s)
Biocompatible Materials/chemistry , Elastomers/chemistry , Liquid Crystals/chemistry , Neurons/cytology , Tissue Scaffolds/chemistry , Cell Proliferation/drug effects , Cells, Cultured , Liquid Crystals/ultrastructure , Porosity , Tretinoin/pharmacology
15.
Langmuir ; 35(10): 3585-3599, 2019 03 12.
Article in English | MEDLINE | ID: mdl-29806980

ABSTRACT

Methodology to combine nanotechnology and these organization processes has been proposed as a novel concept of nanoarchitectonics, which can fabricate functional materials with nanolevel units. As an instant nanoarchitectonics approach, confining systems within a two-dimensional plane to drastically reduce translational motion freedom can be regarded as one of the rational approaches. Supramolecular chemistry and nanofabrication and their related functions at the air-water interface with the concept of nanoarchitectonics would lead to the creation of a novel methodology of Langmuir nanoarchitectonics. In this feature article, we briefly summarize research efforts related to Langmuir nanoarchitectonics including the basics for anomalies in molecular interactions such as highly enhanced molecular recognition capabilities. It is also extended to frontiers including the fabrication of supramolecular receptors and two-dimensional patterns with subnanometer-scale structural regulation, manual control of molecular machines and receptors by hand-motion-like macroscopic actions, and the regulation of cell fates at nanoarchitected arrays of nanocarbon assemblies and at direct liquid interfaces.

16.
Chem Rec ; 19(9): 1891-1912, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30230688

ABSTRACT

The challenges of pollution, environmental science, and energy consumption have become global issues of broad societal importance. In order to address these challenges, novel functional systems and advanced materials are needed to achieve high efficiency, low emission, and environmentally friendly performance. A promising approach involves nanostructure-level controls of functional material design through a novel concept, nanoarchitectonics. In this account article, we summarize nanoarchitectonic approaches to create nanoscale platform structures that are potentially useful for environmentally green and bioprocessing applications. The introduced platforms are roughly classified into (i) membrane platforms and (ii) nanostructured platforms. The examples are discussed together with the relevant chemical processes, environmental sensing, bio-related interaction analyses, materials for environmental remediation, non-precious metal catalysts, and facile separation for biomedical uses.


Subject(s)
Biomimetic Materials/chemistry , Lipid Bilayers/chemistry , Nanoparticles/chemistry , Nanotechnology/methods , Catalysis , Environmental Restoration and Remediation/methods , Green Chemistry Technology/methods
17.
Sci Technol Adv Mater ; 20(1): 51-95, 2019.
Article in English | MEDLINE | ID: mdl-30787960

ABSTRACT

The development of science and technology of advanced materials using nanoscale units can be conducted by a novel concept involving combination of nanotechnology methodology with various research disciplines, especially supramolecular chemistry. The novel concept is called 'nanoarchitectonics' where self-assembly processes are crucial in many cases involving a wide range of component materials. This review of self-assembly processes re-examines recent progress in materials nanoarchitectonics. It is composed of three main sections: (1) the first short section describes typical examples of self-assembly research to outline the matters discussed in this review; (2) the second section summarizes self-assemblies at interfaces from general viewpoints; and (3) the final section is focused on self-assembly processes at interfaces. The examples presented demonstrate the strikingly wide range of possibilities and future potential of self-assembly processes and their important contribution to materials nanoarchitectonics. The research examples described in this review cover variously structured objects including molecular machines, molecular receptors, molecular pliers, molecular rotors, nanoparticles, nanosheets, nanotubes, nanowires, nanoflakes, nanocubes, nanodisks, nanoring, block copolymers, hyperbranched polymers, supramolecular polymers, supramolecular gels, liquid crystals, Langmuir monolayers, Langmuir-Blodgett films, self-assembled monolayers, thin films, layer-by-layer structures, breath figure motif structures, two-dimensional molecular patterns, fullerene crystals, metal-organic frameworks, coordination polymers, coordination capsules, porous carbon spheres, mesoporous materials, polynuclear catalysts, DNA origamis, transmembrane channels, peptide conjugates, and vesicles, as well as functional materials for sensing, surface-enhanced Raman spectroscopy, photovoltaics, charge transport, excitation energy transfer, light-harvesting, photocatalysts, field effect transistors, logic gates, organic semiconductors, thin-film-based devices, drug delivery, cell culture, supramolecular differentiation, molecular recognition, molecular tuning, and hand-operating (hand-operated) nanotechnology.

18.
Chem Rec ; 18(7-8): 676-695, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29205796

ABSTRACT

Important points for the fabrication of functional materials are the creation of nanoscale/molecular-scale units and architecting them into functional materials and systems. Recently, a new conceptual paradigm, nanoarchitectonics, has been proposed to combine nanotechnology and other methodologies including supramolecular chemistry, self-assembly and self-organization to satisfy major features of nanoscience and promote the creation of functional materials and systems. In this account article, our recent research results in materials development based on the nanoarchitectonics concept are summarized in two stories, (i) nanoarchitectonics from fullerenes as the simplest nano-units and (ii) dimension-dependent nanoarchitectonics from various structural units. The former demonstrates creativity of the nanoarchitectonics concept only with simple construction stuffs on materials fabrications, and a wide range of material applicability for the nanoarchitectonics strategy is realized in the latter ones.

19.
Phys Chem Chem Phys ; 20(5): 3073-3078, 2018 Jan 31.
Article in English | MEDLINE | ID: mdl-28759061

ABSTRACT

Intramolecular rotation of molecules contained in a two-dimensional monolayer or a three-dimensional collapsed film at an air-water interface was investigated by in situ fluorescence spectroscopy of twisted intramolecular charge transfer (TICT) type 9-(2-carboxy-2-cyanovinyl)julolidine (CCVJ) derivatives. The TICT type molecules, CCVJ-C12 and CCVJ-Chol, that contain a linear alkyl dodecyl chain or a cholesteryl group, respectively, as their hydrophobic group, were designed and synthesized to manipulate them at the air-water interface. These lipophilized molecular rotors showed the general properties of TICT molecules in solutions that the fluorescence intensity increases with increasing viscosity of the solvent, which is induced by inhibition of internal molecular rotations. The molecular rotors CCVJ-C12 and CCVJ-Chol formed monolayers at the air-water interface and in situ fluorescence spectroscopy was performed during the in-plane compression of the monolayers. It was revealed that the monomer emissions were suppressed and only after the collapse of monolayers, excimer emission from both layers consisting of CCVJ-C12 or CCVJ-Chol was observed. Suppressed monomer emission from monolayers suggests that intramolecular rotation is not inhibited in dense ordered monolayers. Furthermore, fluorescence spectroscopy of Langmuir-Blodgett (LB) films indicated that molecular rotations are not inhibited in the monolayer transferred on the solid substrates.

20.
Angew Chem Int Ed Engl ; 57(31): 9679-9683, 2018 Jul 26.
Article in English | MEDLINE | ID: mdl-29917300

ABSTRACT

Two-dimensional (2D) carbon nanomaterials possessing promising physical and chemical properties find applications in high-performance energy storage devices and catalysts. However, large-scale fabrication of 2D carbon nanostructures is based on a few specific carbon templates or precursors and poses a formidable challenge. Now a new bottom-up method for carbon nanosheet fabrication using a newly designed anisotropic carbon nanoring molecule, CPPhen, is presented. CPPhen was self-assembled at a dynamic air-water interface with a vortex motion to afford molecular nanosheets, which were then carbonized under inert gas flow. Their nanosheet morphologies were retained after carbonization, which has never been seen for low-molecular weight compounds. Furthermore, adding pyridine as a nitrogen dopant in the self-assembly step successfully afforded nitrogen-doped carbon nanosheets containing mainly pyridinic nitrogen species.

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