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1.
Carbohydr Polym ; 319: 121185, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37567719

ABSTRACT

Isomaltomegalosaccharides with α-(1 â†’ 4) and α-(1 â†’ 6)-segments solubilize water-insoluble ligands since the former complexes with the ligand and the latter solubilizes the complex. Previously, we enzymatically synthesized isomaltomegalosaccharide with a single α-(1 â†’ 4)-segment at the reducing end (S-IMS) by dextran dextrinase (DDase), but the chain length [average degree of polymerization (DP) ≤ 9] was insufficient for strong encapsulation. We hypothesized that the conjugation of longer α-(1 â†’ 4)-segment afforded the promising function although DDase is incapable to do so. In this study, the cyclodextrin glucanotransferase-catalyzed coupling reaction of α-cyclodextrin to S-IMS synthesized a new α-(1 â†’ 4)-segment at the nonreducing end (N-4S) of S-IMS to form D-IMS [IMS harboring double α-(1 â†’ 4)-segments]. The length of N-4S was modulated by the ratio between α-cyclodextrin and S-IMS, generating N-4Ss with DPs of 7-50. Based on phase-solubility analysis, D-IMS-28.3/13/3 bearing amylose-like helical N-4S with DP of 28.3 displayed a water-soluble complex with aromatic drugs and curcumin. Small-angle X-ray scattering revealed the chain adapted to rigid in solution in which the radius of gyration was estimated to 2.4 nm. Furthermore, D-IMS with short N-4S solubilized flavonoids of less-soluble multifunctional substances. In our research, enzyme-generated functional biomaterials from DDase were developed to maximize the hydrophobic binding efficacy towards water-insoluble bioactive compounds.

2.
Biomacromolecules ; 23(9): 3978-3989, 2022 09 12.
Article in English | MEDLINE | ID: mdl-36039560

ABSTRACT

Carbohydrates are key building blocks for advanced functional materials owing to their biological functions and unique material properties. Here, we propose a star-shaped discrete block co-oligomer (BCO) platform to access carbohydrate nanostructures in bulk and thin-film states via the microphase separation of immiscible carbohydrate and hydrophobic blocks (maltooligosaccharides with 1-4 glucose units and solanesol, respectively). BCOs with various star-shaped architectures and saccharide volume fractions were synthesized using a modular approach. In the bulk, the BCOs self-assembled into common lamellar, cylindrical, and spherical carbohydrate microdomains as well as double gyroid, hexagonally perforated lamellar, and Fddd network morphologies with domain spacings of ∼7 nm. In thin films, long-range-ordered periodic carbohydrate microdomains were fabricated via spin coating. Such controlled spatial arrangements of functional carbohydrate moieties on the nanoscale have great application potential in biomedical and nanofabrication fields.


Subject(s)
Nanostructures , Carbohydrates , Nanostructures/chemistry
3.
Nanomaterials (Basel) ; 12(10)2022 May 12.
Article in English | MEDLINE | ID: mdl-35630875

ABSTRACT

Block copolymers (BCPs) have garnered considerable interest due to their ability to form microphase-separated structures suitable for nanofabrication. For these applications, it is critical to achieve both sufficient etch selectivity and a small domain size. To meet both requirements concurrently, we propose the use of oligosaccharide and oligodimethylsiloxane as hydrophilic and etch-resistant hydrophobic inorganic blocks, respectively, to build up a novel BCP system, i.e., carbohydrate-inorganic hybrid BCP. The carbohydrate-inorganic hybrid BCPs were synthesized via a click reaction between oligodimethylsiloxane with an azido group at each chain end and propargyl-functionalized maltooligosaccharide (consisting of one, two, and three glucose units). In the bulk state, small-angle X-ray scattering revealed that these BCPs microphase separated into gyroid, asymmetric lamellar, and symmetric lamellar structures with domain-spacing ranging from 5.0 to 5.9 nm depending on the volume fraction. Additionally, we investigated microphase-separated structures in the thin film state and discovered that the BCP with the most asymmetric composition formed an ultrafine and highly oriented gyroid structure as well as in the bulk state. After reactive ion etching, the gyroid thin film was transformed into a nanoporous-structured gyroid SiO2 material, demonstrating the material's promising potential as nanotemplates.

4.
Commun Chem ; 3(1): 135, 2020 Oct 09.
Article in English | MEDLINE | ID: mdl-36703322

ABSTRACT

Discrete block co-oligomers (BCOs) are gaining considerable attention due to their potential to form highly ordered ultrasmall nanostructures suitable for lithographic templates. However, laborious synthetic routes present a major hurdle to the practical application. Herein, we report a readily available discrete BCO system that is capable of forming various self-assembled nanostructures with ultrasmall periodicity. Click coupling of propargyl-functionalized sugars (containing 1-7 glucose units) and azido-functionalized terpenoids (containing 3, 4, and 9 isoprene units) afforded the discrete and monodisperse BCOs with a desired total degree of polymerization and block ratio. These BCOs microphase separated into lamellar, gyroid, and cylindrical morphologies with the domain spacing (d) of 4.2-7.5 nm. Considering easy synthesis and rich phase behavior, presented BCO systems could be highly promising for application to diverse ~4-nm nanofabrications.

5.
Appl Radiat Isot ; 122: 1-6, 2017 04.
Article in English | MEDLINE | ID: mdl-28087998

ABSTRACT

The PRIDE (PyRoprocessing Integrated inactive DEmonstration) is an engineering-scale pyroprocessing test-bed facility that utilizes depleted uranium (DU) instead of spent fuel as a process material. As part of the ongoing effort to enhance pyroprocessing safeguardability, UNDA (Unified Non-Destructive Assay), a system integrating three different non-destructive assay techniques, namely, neutron, gamma-ray, and mass measurement, for nuclear material accountancy (NMA) was developed. In the present study, UNDA's NMA capability was evaluated by measurement of the weight, 238U mass, and U enrichment of oxide-reduction-process feed material (i.e., porous pellets). In the 238U mass determination, the total neutron counts for porous pellets of six different weights were measured. The U enrichment of the porous pellets, meanwhile, was determined according to the gamma spectrums acquired using UNDA's NaI-based enrichment measurement system. The results demonstrated that the UNDA system, after appropriate corrections, could be used in PRIDE NMA applications with reasonable uncertainty. It is expected that in the near future, the UNDA system will be tested with next-step materials such as the products of the oxide-reduction and electro-refining processes.

6.
Oncol Rep ; 27(4): 911-6, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22134685

ABSTRACT

The melanoma antigen gene (MAGE) A1-A6 RT-PCR system was developed for the detection of lung cancer cells in the sputum. However, we identified MAGE expression in some patients with non-malignant lung diseases. To understand these patterns of MAGE expression, we performed MAGE A3 methylation-specific PCR (MSP) and p16 MSP. We collected 24 biopsy specimens of lung cancer tissue and performed MAGE A1-A6 RT-PCR, MAGE A3 MSP and p16 MSP. RNA and DNA were simultaneously extracted from induced sputum specimens of 133 patients with lung diseases and 30 random sputum specimens of healthy individuals and the 3 molecular analyses were performed. The patients were diagnosed as 65 cases of lung cancer and 68 of benign lung diseases. Positive rates of MAGE A1-A6 RT-PCR, MAGE A3 MSP and p16 MSP were as follows: in lung cancer tissue, 87.5, 58.3 and 70.8%; in the sputum of lung cancer patients, 50.8, 46.2 and 63.1%; benign lung diseases, 10.3, 30.9 and 39.7%; and healthy individuals, 3.3, 6.7 and 3.3%. Of the 40 MAGE-positive cases, 33 were diagnosed with lung cancer and 7 as having benign lung diseases. From the 7 cases of MAGE-positive benign lung diseases, 6 cases showed methylation abnormalities. The MAGE-positive group revealed significantly higher rates of methylation abnormalities. Of the 40 MAGE-positive cases, 39 cases were found to be lung cancer or benign lung diseases with abnormal methylation. Thus, MAGE expression in the sputum suggests the presence of lung cancer cells or pre-cancerous cells.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p16/genetics , DNA Methylation , Lung Diseases/genetics , Lung Neoplasms/genetics , Melanoma-Specific Antigens/genetics , Aged , Antigens, Neoplasm/genetics , Biopsy , Case-Control Studies , Chi-Square Distribution , DNA/isolation & purification , Female , Humans , Lung Diseases/pathology , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Proteins/genetics , Predictive Value of Tests , RNA/isolation & purification , Reverse Transcriptase Polymerase Chain Reaction , Sputum/chemistry
7.
Cancer Res Treat ; 39(2): 69-73, 2007 Jun.
Article in English | MEDLINE | ID: mdl-19746211

ABSTRACT

PURPOSE: Bronchial wash fluid may be a useful for detecting lung cancer. To increase the detection rates, we performed molecular analysis with using MAGE A1-6 and SSX4 RT-PCR on bronchial wash fluid specimens. MATERIALS AND METHODS: We obtained 57 lung cancer tissue specimens by bronchoscopic biopsy and 131 bronchial washes from 96 patients with lung cancer and 35 patients with benign lung diseases. The MAGE A1-6 and SSX4 gene expressions were investigated in the cancer tissue specimens and bronchial wash fluids. We evaluated the positive detection rates of these methods according to the cytology results and the clinical findings. RESULTS: For the cancer tissue specimens and the bronchial wash fluid, the positive detection rate of MAGE or SSX4 was 91.2% and 75.0%, respectively. Combined MAGE and SSX4 PCR and cytology tests showed an 83.3% detection rate for the bronchial wash fluid. From bronchial washes of patients with benign lung diseases, the positive rates of using MAGE or SSX4 was 11.4%. In the bronchial wash fluid of lung cancer patients, 66.7% of the peripheral cancers were detected by MAGE or SSX4, while examination with cytology did not detect any peripheral lung cancer. CONCLUSION: The application of both MAGE and SSX4 showed high sensitivity and specificity for the detection of lung cancer. Thus, MAGE and SSX4 RT-PCR may be effectively utilized as additional methods to improve detection of lung cancer with using bronchial wash fluids.

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