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The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) developed the full depth ROV (remotely operated vehicle) UROV11K system. UROV system employed a single microfiber optic cable of 1 mm diameter to carry data telemetry and real time video images. The full depth ROV UROV11K system consists of newly developed full depth vehicle and ABISMO launcher. ABISMO launcher employed a primary cable of ROV KAIKO system. Total 20 km optic fiber cable stored by each spooler was mounted on the vehicle and ABISMO launcher. UROV11K system was designed to perform the scientific surveys at the full depth of 11,000 m. UROV11K sea trial was conducted in May 14, 2017 from the R/V Kairei in Mariana Trench, where the vehicle successfully performed scientific observation with real time 4K video camera images at full depth of 10,899 m. This paper describes an overview of the full depth ROV UROV11K system, advanced elements technologies and the sea trial result.

We describe the use of ion-exchangeable, highly cross-linked polymer films as a matrix for the synthesis of nanocomposite thin films and patterns with embedded Cu and Ni nanoparticles. We have successfully controlled the size of metal nanoparticles and thus optical and magnetic properties of the films by varying the initial amount of doped metal ions.

A simple and sensitive method for measuring telomeric tandem repeat DNA and telomerase activity based on fluorescence resonance energy transfer (FRET) with a FAM-modified 12-mer ODN probe as a donor (fluorophore) and ethidium bromide (EB) as an acceptor (quencher) is proposed. When telomeric DNA and the FAM-modified probe form a duplex, EB intercalates between base-pairs, resulting in fluorescence quenching of FAM through FRET from FAM to EB. This method can be used to estimate the amount of telomeric DNAs in a sample solution as the molar concentration of the telomeric DNA unit [5'-(TTA GGG TTA GGG)-3']. A linear fluorescence quenching ratio was obtained in 5-1000 pM of telomeric DNA units by adjusting the amount of FAM-modified probe. A PCR-free telomerase activity assay using this FRET-based method could be applied to ≥400 HeLa cells per μL. This assay represents a novel technique for initial screenings of cancer diagnosis and is a facile method for quantifying telomeric DNA or other tandem repeat sequences.

G-quadruplex-binding and telomerase-inhibiting capacities of G-quadruplex ligands were examined under a cell nuclei-mimicking condition including excess double-stranded DNA (λ DNA) and molecular crowding cosolute (PEG 200). Under the cell nuclei-mimicking condition, a cationic porphyrin (TMPyP4) did not bind to the G-quadruplex despite the high affinity (Ka = 3.6 × 10(6) M(-1)) under a diluted condition without λ DNA and PEG 200. Correspondingly, TMPyP4 inhibited telomerase activity under the diluted condition (IC50 = 1.6 μM) but not under the cell nuclei-mimicking condition. In contrast, the Ka and IC50 values of an anionic copper phthalocyanine (Cu-APC) under the diluted (2.8 × 10(4) M(-1) and 0.86 μM) and the cell nuclei-mimicking (2.8 × 10(4) M(-1) and 2.1 μM) conditions were similar. In accordance with these results, 10 μM TMPyP4 did not affect the proliferation of HeLa cells, while Cu-APC efficiently inhibited the proliferation (IC50 = 1.4 μM). These results show that the cell nuclei-mimicking condition is effective to predict capacities of G-quadruplex ligands in the cell. In addition, the antiproliferative effect of Cu-APC on normal cells was smaller than that on HeLa cells, indicating that the cell nuclei-mimicking condition is also useful to predict side effects of ligands.

The telomere G-quadruplex-binding and telomerase-inhibiting capacity of two cationic (TMPyP4 and PIPER) and two anionic (phthalocyanine and Hemin) G-quadruplex-ligands were examined under conditions of molecular crowding (MC). Osmotic experiments showed that binding of the anionic ligands, which bind to G-quadruplex DNA via π-π stacking interactions, caused some water molecules to be released from the G-quadruplex/ligand complex; in contrast, a substantial number of water molecules were taken up upon electrostatic binding of the cationic ligands to G-quadruplex DNA. These behaviors of water molecules maintained or reduced the binding affinity of the anionic and the cationic ligands, respectively, under MC conditions. Consequently, the anionic ligands (phthalocyanine and Hemin) robustly inhibited telomerase activity even with MC; in contrast, the inhibition of telomerase caused by cationic TMPyP4 was drastically reduced by MC. These results allow us to conclude that the binding of G-quadruplex-ligands to G-quadruplex via non-electrostatic interactions is preferable for telomerase inhibition under physiological conditions.

International audience; Thioflavin T (ThT), a typical probe for protein fibrils, also binds human telomeric G-quadruplexes with a fluorescent light-up signal change and high specificity against DNA duplexes. Cell penetration and low cytotoxicity of fibril probes having been widely established, modifying ThT and other fibril probes is an attractive means of generating new G-quadruplex ligands. Thus, elucidating the binding mechanism is important for the design of new drugs and fluorescent probes based on ThT. Here, we investigated the binding mechanism of ThT with several variants of the human telomeric sequence in the presence of monovalent cations. Fluorescence titrations and electrospray ionization mass spectrometry (ESI-MS) analyses demonstrated that each G-quadruplex unit cooperatively binds to several ThT molecules. ThT brightly fluoresces when a single ligand is bound to the G-quadruplex and is quenched as ligand binding stoichiometry increases. Both the light-up signal and the dissociation constants are exquisitely sensitive to the base sequence and to the G-quadruplex structure. These results are crucial for the sensible design and interpretation of G-quadruplex detection assays using fluorescent ligands in general, and ThT in particular.

Gold nanoparticles modified with thiol-terminated polystyrene (AuPS) were synthesized and applied to the colorimetric detection of perfluorooctanoic acid (PFOA). The color change of the AuPS solution from red to blue-purple upon addition of PFOA was easily confirmed by the naked eye. Using several acids and fluorinated compounds, the detection system was shown to be selective for PFOA and tridecafluoroheptanoic acid, which suggests that both a highly acidic carboxyl group and a fluorocarbon group are required for the color change. Transmission electron microscopy (TEM) suggested that the addition of PFOA caused detachment of the polystyrene layer from the surface of the gold nanoparticles, which resulted in interparticle aggregation.

Japan Agency for Marine Earth Science and Technology (JAMSTEC) has started a new project “submarine resource research project” in April 2011. We decided to advance the development of work class ROV “KAIKO Mk-IV” as fourth KAIKO's vehicle applied for submarine resource exploration. “KAIKO Mk-IV” construction started in April 2011 and it completed in March 2013. Then, its sea trials have been carried out in FY2013-FY2015. This paper describes about the development of new ROV (vehicle) “KAIKO Mk-IV” and those equipment using advanced technologies and test results.

The G-quadruplex, a four-stranded DNA structure with stacked guanine tetrads (G-quartets), has recently been attracting attention because of its critical roles in vitro and in vivo. In particular, the G-quadruplex functions as ligands for metal ions and aptamers for various molecules. Interestingly, the G-quadruplex can show peroxidase-like activity with an anionic porphyrin, iron (III) protoporphyrin IX (hemin). Importantly, hemin binds to G-quadruplexes with high selectivity over single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA), which is attributable to an electrostatic repulsion of phosphate groups in ssDNA and dsDNA. The G-quadruplex and hemin-G-quadruplex complex allow development of sensing techniques to detect DNA, metal ions and proteins. In addition to hemin, anionic phthalocyanines also bind to the G-quadruplex formed by human telomere DNA, specifically over ssDNA and dsDNA. Since the binding of anionic phthalocyanines to the G-quadruplex causes an inhibition of telomerase activity, which plays a role in the immortal growth of cancer cells, anionic phthalocyanines are promising as novel anticancer drug candidates. This review focuses on the specific binding of hemin and anionic phthalocyanines to G-quadruplexes and the applications in vitro and in vivo of this binding property.

Magnetic composite nanostructures composed of a dielectric matrix containing magnetic nanoparticles offer opportunities for the fabrication of next-generation magnetic devices, in addition to providing a fundamental understanding of nanomagnetism. However, a synthetic strategy for the fine-tuning of such composite nanostructures is required. Herein, we report an analytical study on the structural tuning of composite thin layers of a polyimide matrix containing nickel nanoparticles. Control of the composite layer microstructure was achieved by decomposition of the polyimide matrix using the nickel nanoparticles as a catalyst, which resulted in weight loss and thus shrinkage of the composite layer volume. Several analytical experiments were conducted for films annealed at a constant temperature for different time intervals and hydrogen partial pressures to identify the chemical structures of decomposition products and to elucidate the reaction mechanism of the metal-catalyzed decomposition process. The deco...

A novel, facile DNA detection method based on aggregation/ disaggregation of an AIE (aggregation induced emission) dye- labeled peptide nucleic acid (PNA) probe was developed. This PNA probe plays the role of both target recognition and signal emission, thus it can quantify the target DNA without requiring additives such as intercalators and can distinguish the target from other sequences.

A strategy for arranging two porphyrin moieties in a face-to-face fashion in polymeric material was demonstrated by molecular imprinting, whereby porphyrin Zn(II) complex monomers were cross-linked with ethylene glycol dimethacrylate in the presence of pyrazine or 1,5-naphthyridine as a template molecule. In chromatographic studies using the resultant imprinted polymers as stationary phase, both the polymers showed selectivity for the original template molecule, suggesting that two zinc porphyrin moieties were immobilized in the face-to-face fashion, and were center-aligned for pyrazine recognition and offset-arranged for 1,5-naphthyridine recognition. The imprinted polymer with porphyrin moieties also showed a decrease in its fluorescence intensity in response to the concentration of the target molecule, suggesting the potential utility as sensing material.

The Carica papaya lipase-catalyzed acylation of benzylcarbinols with vinyl hexanoate proceeded smoothly and enantiospecifically (E > 200), affording the R-esters and leaving the S-alcohols intact. Thus, this plant lipase proved to be a promising biocatalyst for the resolution of alcohols as well as for that of carboxylic acids reported earlier.

Candida antarctica lipase B (CAL-B) was found to be a highly active biocatalyst for the direct acylation of the phenolic hydroxyls of substituted hydroquinones and resorcinols with vinyl propanoate as an acyl donor. The acylation reactions took place generally in a very regioselective manner. Especially in the case of 4-substituted resorcinols, the hydroxyl remote from the substituent was regiospecifically acylated to afford only the 1-O-propanoylated resorcinols.

Candida antarctica lipase B (CAL-B) was found to be highly regioselective as well as active in the deacylation of resorcinols and hydroquinones acylated at both phenolic hydroxyls. Contrary to expectation, secondary alcohols acted as better nucleophiles than primary alcohols in these enzymatic deacylations.

The DNAs modified with tetraphenyl porphyrin at the center of 13mer oligonucleotide were synthesized using phosphoramidite chemistry and automated DNA synthesis. When the porphyrin modified oligonucleotide was annealed with its complementary strand, they formed a standard B-form duplex. The porphyrin moiety intercalated in the duplex, and moderately lowered the thermal stability.

Molecular crowding, an important feature of the molecular environments in biological cells, was applied to the synthesis of antibody-mimic polymers selective for a group of biologically active compounds, the triazine herbicides. Synthesis of these polymers was conducted using molecular imprinting under molecular crowding conditions, whereby atrazine (a template molecule) was complexed with methacrylic acid (a functional monomer) in the presence of a macromolecular crowding agent (either poly(methyl methacrylate) (PMMA) or polystyrene (PS)) followed by cross-linking with ethylene glycol dimethacrylate. After removal of atrazine from the polymer matrix, the retention properties and selectivity of the resultant polymers were assessed by chromatographic tests. The addition of a crowding-inducing agent resulted in polymers with superior retention properties and excellent selectivity for triazine herbicides, as compared to polymers prepared without addition of a crowding-inducing agent. An imprinted polymer prepared in the presence of PS as a crowding agent exhibited a retention factor for atrazine an order of magnitude larger than that of an imprinted polymer prepared in the absence of a crowding agent. NMR results suggest that the crowding agent is capable of promoting hydrogen bond formation between atrazine and methacrylic acid, which could account for the effect of crowding on molecular imprinting.

G-quadruplex-based drug delivery carriers (GDDCs) were designed to capture and release a telomerase inhibitor in response to a target mRNA. Hybridization between a loop on the GDDC structure and the mRNA should cause the G-quadruplex structure of the GDDC to unfold and release the bound inhibitor, anionic copper(II) phthalocyanine (CuAPC). As a proof of concept, GDDCs were designed with a 10-30-mer loop, which can hybridize with a target sequence in epidermal growth factor receptor (EGFR) mRNA. Structural analysis using circular dichroism (CD) spectroscopy showed that the GDDCs form a (3 + 1) type G-quadruplex structure in 100 mM KCl and 10 mM MgCl2 in the absence of the target RNA. Visible absorbance titration experiments showed that the GDDCs bind to CuAPC with Ka values of 1.5 × 10(5) to 5.9 × 105 M(-1) (Kd values of 6.7 to 1.7 μM) at 25 °C, depending on the loop length. Fluorescence titration further showed that the G-quadruplex structure unfolds upon binding to the target RNA with Ka values above 1.0 × 10(8) M(-1) (Kd values below 0.01 μM) at 25 °C. These results suggest the carrier can sense and bind to the target RNA, which should result in release of the bound drug. Finally, visible absorbance titration experiments demonstrated that the GDDC release CuAPC in response to the target RNA.

Pseudomonas sp. lipase-catalyzed enantioselective acylation procedure using acid anhydrides as acyl donors was exploited for the resolution of 2-aryloxy-1-propanols carrying different substituents on the benzene ring. These primary alcohols, which belong to primary alcohols with an oxygen atom at the stereocenter, were resolved generally with moderate to good enantioselectivity (E of up to 55) through the acylation with hexanoic anhydride in diisopropyl ether at 25 °C in a short reaction time. With the alcohol substrate, which gave a low enantioselectivity in the acylation at ordinary temperature, the selectivity proved to be enhanced by conducting the reaction at low temperature (−10 °C). By this acylation procedure employing the acid anhydride, enantiomerically pure (R)-2-phenoxy-1-propanol was prepared in a gram-scale reaction.

Water-soluble bicycloporphyrin and benzoporphyrin having octacarboxyl groups are synthesized from the corresponding octaester porphyrin by simple hydrolyzing and heating procedures. These compounds are characterized by UV–vis, NMR and mass spectroscopies. The benzoporphyrin octacarboxylic acid exhibits extremely high planarity in spite of its poly-substitution.

Tripeptides containing a novel α,α-disubstituted glycine with two pyridine rings, α,α-di(2-pyridyl)glycine (2Dpy), were synthesized by the solid-phase Ugi reaction using di(2-pyridyl)methanimine attached directly to a Rink amide resin. Thereby, yields of the tripeptides, Z-AA 1 -2Dpy-AA 3 -OMe (AA 1 and AA 3 = Gly or Aib), were markedly improved, compared with yields by the solution method.

Four tripeptides (Z-AA1-2Dpy-AA3-OMe; AA1, AA3 = Gly, Aib) containing a novel amino acid, alpha, alpha-di(2-pyridyl)glycine (2Dpy), were synthesized by the modified Ugi reaction. NMR analysis clearly indicated that the 2Dpy-containing tripeptides except the peptide in which AA1, AA3 = Aib, adopt a unique conformation with two intramolecular hydrogen bonds between 2Dpy-NH and a pyridine nitrogen and between AA3-NH and another pyridine nitrogen. This conformation has so far not been reported. On the other hand, the peptide Z-Aib-2Dpy-Aib-OMe probably adopts a beta-turn structure which is stabilized by two intramolecular hydrogen bonds between 2Dpy-NH and a pyridine nitrogen and between AA3-NH and the C=O of the Z group.

We examined Aspergillus melleus protease (Amano protease P) and A. oryzae protease (Amano protease A) as catalysts for peptide bond formation via the kinetically controlled approach. As the coupling efficiency was only moderate, even with a good amino acid substrate as the carboxyl component, in acetonitrile as a solvent (with or without a small amount of added water) that we had mainly employed previously in α-chymotrypsin catalyzed couplings, other solvent systems were sought. In 1,1,1,3,3,3-hexafluoro-2-propanol-DMF (1:1) without added water, these Aspergillus proteases were found to remain active for a long period of time and to be utilizable for peptide synthesis when the carbamoylmethyl ester was employed as the acyl donor, though the coupling efficiencies were dependent rather largely on the combination of the amino acid residues at the coupling site. The superiority of the carbamoylmethyl ester to conventional esters, for example the methyl ester, was once again established. Furthermore, some segm...

The coupling between the carbamoylmethyl ester of an N-protected amino acid or dipeptide (at 25 mM) and an amino acid amide (at 100 mM) was achieved using Aspergillus melleus protease in 1,1,1,3,3,3-hexafluoro-2-propanol/N,N-dimethylformamide (1:1, v/v); the coupling efficiencies were dependent largely on the combination of amino acid residues: e.g. the dipeptide yields after 48 h were for l-Ala + Gly, ∼100% and for l-Leu + l-Leu, 16%.

The couplings of N-protected amino acid esters with amino acid amides proved to be carried out in anhydrous acetonitrile in the presence of Bacillus licheniformis protease (subtilisin Carlsberg) immobilized on Celite. The maximal peptide yields were obtained with the immobilized enzyme prepared through lyophilization from a pH 10.7 buffer solution. A series of dipeptide syntheses and several segment condensations were achieved generally in high yields by the combined use of the immobilized enzyme prepared from this pH and the carbamoylmethyl ester as the acyl donor.

Polypyrrole annelated with bicyclo[2.2.2]octene provides a new material that possesses a raised HOMO band, extended conjugation and a rigid porous structure. © 2001 Elsevier Science Ltd.

Conjugated oligomers based on a combination of thiophene and 3,4-dialkoxythiophene moieties have been synthesized via the Vilsmeier formylation, Wittig-Honer reaction, and McMurry coupling reaction starting from dimethyl 3,4-dihydroxythiophene-2,5-dicarboxylates. Comparison of the optical and electrochemical properties shows that the mixed π-conjugated oligomers of thiophene and 3,4-dialkoxythiophene produces a decrease of the highest occupied molecular orbital-lowest unoccupied molecular orbital gap that is attributed to the electron-donating property of the alkoxy groups. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:414–417, 2001

Three series of dimers containing pyrrolo[3,4-e][2,1,3]benzothiadiazole units have been prepared by application of the Pd-catalyzed Suzuki coupling. The dependence of the HOMO–LUMO separation on coplanarity has been evaluated by means of electronic absorption spectra and cyclic voltammetry. The pyrrole dimer 5c shows a narrow HOMO–LUMO separation owing to its intrinsically planar structure, as confirmed by 1H NMR.

Stable 2H-isoindoles with electron-withdrawing groups were prepared using the reaction of dinitrobenzene derivatives with isocyanoacetate in the presence of DBU. The use of acetonitrile as the solvent or a phosphazene base (BTPP) as a non-ionic base improved the yields. The structure was confirmed by X-ray crystallographic analysis of the compound 2e′. According to the X-ray analysis, this substance existed in the solid phase only as the 2H-isomer.

Pyrroles fused with bicyclo[2.2.2]octene and bicyclo[2.2.1]heptene frameworks are prepared by a modified Barton–Zard method. Structures of these pyrroles and thermal behaviours of the former pyrroles are studied by X-ray and DSC analyses.

Pyrroles having long alkoxy groups on the β-position are prepared and utilized as precursors for polypyrrolenevinylenes. The resulting polymers exhibit high solubility not only in a moderately polar solvent but also in a nonpolar solvent such as hexane. These polymers have deep-blue color in the neutral state, while in the doped state the color is completely faded to transparent.

The Diels–Alder reaction of β-sulfonylnitroethylene with cyclopentadiene, cyclohexadiene or substituted anthracenes followed by treatment with ethyl isocyanoacetate in the presence of DBU gives pyrroles fused with bicyclo[2.2.1]heptadiene and bicyclo[2.2.2]octadiene skeletons, or triptycene-types of pyrrole, respectively, which are precursors for novel porphyrins fused with polycyclic skeletons.

Two classes of nitro heteroaromatic compounds such as quinoxalines 7a,b and benzothiaselenadiazoles 7c,d with ethyl isocyanoacetate in the presence of 1,8-diazabicyclo[5,4,0]undec-7-ene g gave the corresponding pyrimidine N-oxides 8a-d, whilst, in contrast, use of proazaphosphatrane 2 or iminophosphorane 4 as a base under similar conditions gave the corresponding pyrroles 9a-d.

Nitre heteroarenes react with ethyl isocyanoacetate in the presence of 1,8-diazabicyclo[5.4.0]undecene (DBU) to give pyrroles or pyrimidine N-oxide depending on the structure of the starting nitro compounds. For example, 4-nitro-2,1,3-benzothiadiazole 3a reacted with ethyl isocyanoacetate to give ethyl 2,1,3-benzothiadiazole[3,4-c]pyrrole-2-carboxylate 4a (33%), while a similar reaction with 5-nitro-2,1,3-benzothiadiazole 3b gave the corresponding compound 4b (21%) as a sole product. A plausible mechanism for these reactions is presented.

Pyrroles fused with crown ethers are prepared by the reaction of 3,4-dihydroxy pyrrole 1 and polyethylene glycol ditosylate 2 in the presence of cesium fluoride using a convenient high dilution method. These pyrroles can be converted into the corresponding porphyrins with four crown ether moieties, which are expected to form ion channels.

Pyrroles substituted with long alkoxy groups are prepared by the reaction of iminodiacetic acid dimethyl ester and dimethyl oxalate and the subsequent alkylation. These pyrroles are good precursor molecules for the corresponding porphyrins, which are expected to form an ordered columnar mesophase and are able to co-ordinate to various metals.

Performing oceanographic measurements from the sea surface to the sea bottom is technically challenging under rough or icy sea conditions. In 2011, we tested measures for protecting a buoy under such severe conditions, by incorporating anti-icing and tolerance to high winds and rough seas. Based on the results, we carried out detailed designs of a suitable buoy system. In January 2012, we succeeded in deploying the buoy in the Southern Ocean off the Adelie Coast at 60°S and 140°E. Some of the meteorological and oceanographic data being gathered by the buoy can now be monitored in real time. In this paper, we describe some details concerning the design of the sensor pole and mooring line, in addition to the data already received from the buoy.

A G-quadruplex is a four-stranded DNA structure featuring stacked guanine tetrads, G-quartets. Formation of a G-quadruplex in telomere DNA can inhibit telomerase activity; therefore, development of G-quadruplex-ligands, which induce and/or stabilize G-quadruplexes, has become an area of great interest. Phthalocyanine derivatives have substantial potential as high-affinity G-quadruplex-ligands because these planar chromophores are similar in size and shape to the G-quartets. Here, we focus on the latest findings on phthalocyanine derivatives as G-quadruplex-ligands, and discuss the mechanisms by which phthalocyanines bind to G-quadruplexes with high affinity and selectivity. We also discuss potential biomedical and organic electronic applications of phthalocyanines that are dependent on their photophysical properties.