Expression of Tn and sialyl-Tn antigens in the neoplastic transformation of uterine cervical epithelial cells

The expression of simple mucin-type carbohydrate antigens, Tn and sialyl-Tn antigens, was evaluated by immunohistochemical staining with monoclonal antibodies in normal squamous epithelium, dysplasia, carcinoma in situ, and invasive squamous cell carcinoma of the uterine cervix. The expression of the Tn antigen detected by HB-Tn1 and B1.1 was found in 17 (20%) and 19 (23%) of the 83 invasive carcinomas, respectively, but was not found in the 36 normal squamous epithelia, 22 severe dysplasias, or 24 carcinomas in situ. The sialyl-Tn antigen was detected by HB-STn1 and TKH-2 in 14 (64%) and 11 (50%) of the 22 severe dysplasias, 13 (54%) and 10 (42%) of the 24 carcinomas in situ and 48 (58%) and 42 (51%) of the 83 invasive carcinomas, respectively, but was completely absent in 36 normal squamous epithelia. Coexpression of the sialyl-Tn antigen was observed in 89% of the cases expressing the Tn antigen. No significant difference was observed between the immunoreactivities of the antigens in the metastatic lymph nodes and primary tumors. No correlation was found between the expression of each antigen and clinical state, histologic type, depth of invasion, parametrial spread, lymphatic and vessel permeation, lymph node metastasis, or 5-year survival rate. The expression of Tn and sialyl-Tn demonstrates a specific change in the neoplastic progression from carcinoma in situ to invasive carcinoma and from normal to dysplasia, respectively, in squamous cell neoplastic lesions of the cervix. Tn and sialyl-Tn antigens may be useful markers for biologic investigation of neoplastic transformation in cervical squamous cell carcinoma.     

Biosynthesis and characterization of novel polyhydroxyalkanoate copolymers consisting of 3-hydroxy-2-methylbutyrate and 3-hydroxyhexanoate

In this study, in order to explore the possibility of biosynthesizing a novel polyhydroxyalkanoate (PHA), copolymerization of 3-hydroxy-2-methylbutyrate (3H2MB) as the α-position methylated monomer and 3-hydroxyhexanoate (3HHx) as the medium-chain-length monomer was performed to obtain P(3H2MB-co-3HHx). The β-oxidation-deficient Escherichia coli LSBJ, harboring the PHA biosynthetic operon from Aeromonas caviae and the propionyl-CoA transferase gene (pct) from Megasphaera elsdenii, was cultured with feeding tiglic and hexanoic acids as the precursors for 3H2MB and 3HHx, respectively. It was observed that pct expression was highly effective to enhance the incorporation of 3H2MB into PHA. The biosynthesized PHA was composed of 3H2MB and 3HHx units only, and the 3H2MB fraction varied in the range of 36–60 mol% depending on the culture conditions. These PHAs exhibited glass transition temperatures between ?11 to ?17 °C; moreover, no melting peak was observed during analysis using differential scanning calorimetry. This study demonstrated the biosynthesis of a hitherto unreported PHA by engineering metabolic pathway in E. coli.     

Production of 8,11,14,17-cis-eicosatetraenoic acid by Δ5 desaturase-defective mutants of an arachidonic acid-producing fungus, Mortierella alpina

Δ5 Desaturase-defective mutants of an arachidonic acid-producing fungus, Mortierella alpina 1S-4, accumulate large amounts of 8,11,14,17-cis-eicosatetraenoic acid (20:4ω3) when grown with linseed oil. One of the mutants, the S14 strain, produced 1.65 mg of 20:4ω3 per mL of culture medium (corresponding to 66.0 mg/g dry mycelia and 11.6% of total cellular fatty acids) when grown in a medium containing 1% glucose, 1% yeast extract, and 4% linseed oil methyl ester at 28°C for 2 d, and then at 16°C for 7 d. In a bench-scale fermentation in a 5-L jar fermenter, 20:4ω3 production reached 1.60 g/L of culture medium on the eighth day (corresponding to 77.3 mg/g dry mycelia and 26.0% of total cellular fatty acids). The cellular lipids of the S14 strain comprised 75.8% triacylglycerol (TG), 6.7% diacylglycerol, and 13.3% phospholipids (PL). The percentage of 20:4ω3 was higher in PL than in TG, and highest in phosphatidylcholine (32.6%).     

Epitaxial growth of binary and ternary metallic strained superlattices and their magnetic properties

Since the structure at/near the interface of superlattices influences physical properties such as magnetic property, it is important to investigate details of the structure. The interface structure is characterized by the factors like atomic species, strain, mixing and roughness. The reflection high-energy electron diffraction (RHEED) system installed in our molecular-beam epitaxy (MBE) system enables us to observe, continuously, the change of the surface in-plane lattice constant, which is affected by atomic species, strain and/or mixing, on a realtime basis. Ternary superlattices consisting of three elements can clarify the effect of stacking sequence by comparison between the two types of superlattices with the reverse deposition sequences, since the effect caused by the combination of the same atomic species is cancelled out and the effect caused by the different stacking sequences remains. In the present paper, we review growth behaviors of binary and ternary metallic strained superlattices, especially magnetic ones, investigated mainly by our group, and summarize the discussion on their magnetic properties, mainly on the magnetic anisotropy, in terms of their structural characteristics. First, we introduce our RHEED system that works efficiently under a magnetic field arising from evaporation sources for low vapor-pressure materials. Then, MBE-grown binary strained superlattices, Co/Au, Co/Pt and Cu/Au, are discussed, with comparing to incoherent superlattices of Co/Ag and Cu/Ag having nearly the same lattice mismatch of constituents. Next, we review ternary strained superlattices with immiscible constituents with reverse deposition order, Au/Co/Ag and Ag/Co/Au superlattices, and Au/Co/Cu and Cu/Co/Au superlattices, in relation to the growth behaviors of binary superlattices. Finally, ternary strained superlattices containing both miscible and immiscible constituents, Pt/Co/Ag and Ag/Co/Pt superlattices, and Au/Ni/Ag and Ag/Ni/Au superlattices, are reviewed.     

Size and surface modification of amorphous silica particles determine their effects on the activity of human CYP3A4 in vitro

Because of their useful chemical and physical properties, nanomaterials are widely used around the world - for example, as additives in food and medicines - and such uses are expected to become more prevalent in the future. Therefore, collecting information about the effects of nanomaterials on metabolic enzymes is important. Here, we examined the effects of amorphous silica particles with various sizes and surface modifications on cytochrome P450 3A4 (CYP3A4) activity by means of two different in vitro assays. Silica nanoparticles with diameters of 30 and 70 nm (nSP30 and nSP70, respectively) tended to inhibit CYP3A4 activity in human liver microsomes (HLMs), but the inhibitory activity of both types of nanoparticles was decreased by carboxyl modification. In contrast, amine-modified nSP70 activated CYP3A4 activity. In HepG2 cells, nSP30 inhibited CYP3A4 activity more strongly than the larger silica particles did. Taken together, these results suggest that the size and surface characteristics of the silica particles determined their effects on CYP3A4 activity and that it may be possible to develop silica particles that do not have undesirable effects on metabolic enzymes by altering their size and surface characteristics.     

Thermal neutron imaging with rare-earth-ion-doped LiCaAlF6 scintillators and a sealed Cf source

Thermal neutron imaging with Ce-doped LiCaAlF₆ crystals has been performed. The prototype of the neutron imager using a Ce-doped LiCaAlF₆ scintillating crystal and a position sensitive photomultiplier tube (PSPMT) which had 64 multi-channel anode was developed. The Ce-doped LiCaAlF₆ single crystal was grown by the Czochralski method. A plate with dimensions of a diameter of 50×2 mm² was cut from the grown crystal, polished, and optically coupled to PSPMT by silicone grease. The ²⁵²Cf source (<1 MBq) was sealed with 43 mm of polyethylene for neutron thermalization. Alphabet-shaped Cd pieces with a thickness of 2 mm were used as a mask for the thermal neutrons. After corrections for the pedestals and gain of each pixel, we successfully obtained two-dimensional neutron images using Ce-doped LiCaAlF₆.     

Luminescence properties and gamma-ray response of the Ce and Ca co-doped (Gd,Y)F3 single crystals

The Ca0.5% and Ce1%, 3%, 7%, 10% co-doped Gd_0.5Y_0.5F₃ single crystals were grown by the μ-PD method. In the Ca0.5% and Ce3% co-doped sample, Ce³⁺-perturbed luminescence at 380 nm was observed with 32.4 ns photoluminescence decay time. The energy transfer in the sequence of the regular Ce³⁺→ (Gd³⁺)_n→ the perturbed Ce³⁺ sites was evidenced through observation of decay time shortening of the regular Ce³⁺ and Gd³⁺ centers and the change between the Gd³⁺ and Ce³⁺-perturbed emission intensity. The gamma-ray excited scintillation response of the Ca0.5%, Ce7% co-doped Gd_0.5Y_0.5F₃ sample was investigated with the help of the pulse height spectra and the light yield, energy resolution and non-proportionality was evaluated in the interval of energies of 59.4-1274 keV.     

Super black and ultrathin amorphous carbon film inspired by anti-reflection architecture in butterfly wing

An ultrathin and super black amorphous carbon (a-C) film has been fabricated by borrowing the inverse V-type anti-reflection nano-architecture from the black wings of butterfly Ornithoptera goliath through vacuum sintering process. The biomimetic a-C film shows good optical absorption (99%) at low reflectance (<1%) in visible light (380–795 nm), which is comparable to the previously fabricated darkest materials, while with a thickness (5 μm) of only 15% of those materials. Experimental results as well as theoretical simulation which is based on finite difference time domain method (FDTD) show that reflection of the fabricated inverse V-type structured a-C film is merely 1/13 of that of the flat surface a-C film, and 1/8 of that of glassy carbon. Complex refractive index of the derived a-C for visible light (380–795 nm) has also been calculated.