Katsutoshi Yamamoto

Induction of inflammatory arthropathy resembling rheumatoid arthritis in mice transgenic for HTLV-I

Human T cell leukemia virus type-I (HTLV-I) is the etiologic agent of adult T cell leukemia and has also been suggested to be involved in other diseases such as chronic arthritis or myelopathy. To elucidate pathological roles of the virus in disease, transgenic mice were produced that carry the HTLV-I genome. At 2 to 3 months of age, many of the mice developed chronic arthritis resembling rheumatoid arthritis. Synovial and periarticular inflammation with articular erosion caused by invasion of granulation tissues were marked. These observations suggest a possibility that HTLV-I is one of the etiologic agents of chronic arthritis in humans.

Detection of human T cell lymphotropic virus type I proviral DNA and its gene expression in synovial cells in chronic inflammatory arthropathy.

To investigate the pathogenesis of human T cell lymphotropic virus type I (HTLV-I)-associated chronic inflammatory arthropathy (HAAP), we sought to detect proviral DNA in the articular lesions. For the detection of proviral DNA, we used the polymerase chain reaction (PCR). Proviral DNA was detected not only in the peripheral blood mononuclear cells (PBMCs) and synovial fluid cells (SFCs), but also in the T lymphocyte-depleted cultured synovial cells (CSCs). These findings suggest that the infection by HTLV-I might occur in vivo in non-T cells. Furthermore, we detected HTLV-I tax1/rex1 messenger RNA in fresh synovial tissues and CSCs but not in fresh PBMCs and fresh SFCs using reverse transcription and PCR. Immunohistochemically, the CSCs from HAAP patients were also shown to express the HTLV-I antigens. These data indicate that HTLV-I in the non-T synovial cells can be transcribed and expressed. Moreover, the sequences of pXII regions in the CSCs demonstrated 97.5-99.4% homology to that in MT-2 cells, HTLV-I-infected cell line. This confirmed that the PCR-amplified bands reflect HTLV-I itself. These results suggest that this organ-specific inflammation can be attributed to non-T cell virus infection in articular lesions.

Overgrowth of human synovial cells driven by the human T cell leukemia virus type I tax gene

One of the salient pathological features of rheumatoid arthritis is synovial cell proliferation with bone erosion. Despite extensive investigation, the factors essential for synovial cell proliferation remain to be identified. Recent studies suggest that human T cell leukemia virus type I (HTLV-I) may play an important role in synovial overgrowth observed in patients with one type of chronic inflammatory synovitis. In order to confirm and extend these observations, we have established synovial cell clones (SCCs) from three HTLV-I carriers who demonstrated synovial overgrowth but were otherwise asymptomatic. HTLV-I proviral DNA randomly integrated into the cellular genome was present in 20-30% of SCCs. The SCCs carrying HTLV-I proviral DNA and expressing the tax gene exhibited high levels of proliferative potential. HTLV-I was found to function as a transcriptional trans-activator in these SCCs. Moreover, transfection of the tax expression plasmid into SCCs resulted in the same phenotype of increased proliferation and cytokine expression as exhibited by HTLV-I provirus-carrying and tax-expressing SCCs. These data suggest that tax plays a critical role not only in leukemogenesis but also in synovial overgrowth in humans.

Organic functionalization of mesoporous molecular sieves with Grignard reagents

Abstract Grignard reagents were employed for the first time to organically functionalize a mesoporous silica, MCM-41. 29 Si-and 13 C-MAS-NMR spectra proved that Grignard reagents modified the surface of MCM-41, forming stable Si–C bonds from surface silanol groups via alkoxy species without damaging the ordered structure of MCM-41. The degree of organic functionalization depended on the size of the used Grignard reagents. These organically functionalized MCM-41 materials exhibited high hydrophobicity and remarkable hydrothermal stability.

Synthesis, characterization, and catalysis of UTM-1: an MTF-type zeolite composed of the same building unit as MFI-type zeolites

Abstract Synthesis conditions for an MTF-type zeolite UTM-1 have been studied and this material has been characterized in detail. UTM-1 is crystallized in the presence of hexamethyleneimine (HMI) under the synthesis conditions similar to those of MCM-22 but from mother gels with high SiO2/Al2O3 ratio at a narrow range of synthesis temperatures. The crystal growth of UTM-1 proceeds quite rapidly after a long induction period in contrast to the gradual crystal growth of MCM-22. Through the optimization of synthesis conditions, pure silica and Ti-incorporated materials with the MTF structure can be easily synthesized in the hydroxide media without employing any co-template other than HMI. UTM-1 is proved to have strong acidity comparable to that of ZSM-5 having a similar SiO2/Al2O3 ratio, presumably reflecting their structural similarity. UTM-1 has large outer surface area so as to show high catalytic activities in reactions occurring at the outer surface of the catalyst, whereas its small pore aperture restricts the diffusivity of reactant molecules into the pore system.

Separation and Recovery of Tetramethyl Ammonium Hydroxide with Mesoporous Silica Having a Hexagonal Structure (MCM-41)

Separation and recovery of tetramethyl ammonium hydroxide (TMAH) was investigated using several types of MCM-41 (mesoporous silica having hexagonal structure) adsorbents. The MCM-41s were prepared by hydrothermal synthesis with structure-directing agents with different alkyl chains. The prepared MCM-41s were characterized with X-ray diffraction, transmission electron microscope, nitrogen gas adsorption, and zeta potential, and then used for adsorption of TMAH. The adsorption of TMAH with MCM-41s increased with pH up to pH ≈ 10 and then decreased as the MCM-41 dissolved. The adsorption of TMAH progressed via the Langmuir mechanism. The maximum adsorption corresponded to the pore diameter and the pore volume of the MCM-41s. MCM-41 also possesses selectivity for TMAH against phenol. The chromatographic operation was conducted using granulated MCM-41 to avoid excessive pressure-drop through the packed column and quantitative adsorption-elution processing of TMAH could be achieved.

21-P-16-Synthesis of zeolites with organic lattice

Publisher Summary This chapter discusses the synthesis of zeolites with organic lattice. Organic–inorganic hybrid zeolites with organic lattice are successfully synthesized by using organically bridged silane as a silica source. 29 Si and 13 C magic angle spinning nuclear magnetic resonance (MAS NMR) spectra and infrared (IR) spectra prove the presence of organic lattice (Si–CH 2 –Si) partially replacing siloxane bond (Si–O–Si), although some of Si–C bonds are cleaved. Their unit cell sizes are slightly larger than those of their completely inorganic counterparts presumably because of the longer bond length of Si–C than that of Si–O. When synthesized in the absence of organic template molecules, they exhibit microporosity just as ordinary zeolites.

Thermogravimetric study for the reaction of BaTiO3 with CS2 by using quartz spring-type thermobalance

The sulfurization behavior of BaTiO 3 fine particles was studied by thermogravimetry (TG) using CS 2 . The sulfurization process of the fine particles was carried out at a heating rate of 1 °C min -1 by using a quartz spring-type thermo balance in a CS 2 /N 2 gas flow. The obtained TG curve showed that the sulfurization of BaTiO 3 fine particles started at around 380°C, which was considerably low compared with those found for two commercial BaTiO 3 powders. The sulfurization occurred up to approximately 730°C with a maximun weight gain of 19.2% forming BaTiS 3 . At further elevated temperatures, the BaTiS 3 lost a small amount of sulfur to give BaTiS 3-x as a final product at 1000°C.

Epoxidation of Alkenes Catalyzed by Decatungstate as Pillars in Layered Double Hidroxides

Abstract Hydrotalcite pillared by decatungstate was synthesized via organic anion precursors. This pillared hydrotalcite catalyzed epoxidation of alkenes with H2O2 with significant shape selectivity; epoxidation of larger alkenes was less favored than smaller alkenes. The subsequent hydrolysis of epoxides to form diols was retarded compared to hydrotalcite-free catalysts.

Amphiphilic Organic–Inorganic Hybrid Zeotype Aluminosilicate like a Nanoporous Crystallized Langmuir–Blodgett Film†

A new organic-inorganic hybrid zeotype compound with amphiphilic one-dimensional nanopore and aluminosilicate composition was developed. The framework structure is composed of double aluminosilicate layers and 12-ring nanopores; a hydrophilic layer pillared by Q(2) silicon atom species and a lipophilic layer pillared by phenylene groups are alternately stacked, and 12-ring nanopores perpendicularly penetrate the layers. The framework topology looks similar to that of an AFI-type zeolite but possesses a quasi-multidimensional pore structure consisting of a 12-ring channel and intersecting small pores equivalent to 8-rings. The hybrid material with alternately laminated lipophilic and hydrophilic nanospaces can be assumed as a crystallized Langmuir-Blodgett film. It demonstrates microporous adsorption for both hydrophilic and lipophilic adsorptives, and its outer surface tightly adsorbs lysozyme whose molecular size is much larger than its micropore opening. Our results suggest the possibility of designing porous adsorbent with high amphipathicity.