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Advanced electric propulsion systems have been developed by utilizing superconducting technologies to reduce carbon dioxide emissions from aircraft. This study presents the progress in the development of a 400 kW-class fully superconducting synchronous motor using REBa2Cu3O7−δ (REBCO) tape. REBCO tapes have high critical current densities; thus, they can generate a strong magnetic field without an iron core, permitting the fabrication of small-sized motors compared with conventional motors that use copper wires and iron cores. The 400 kW-class fully superconducting synchronous motor comprises field and armature coils. The field coil was wound with cos-theta-like racetrack distribution to generate a dipole field without an iron core. The maximum magnetic field is 1.45 T when the operating current is 110 A DC. The armature coil comprises six racetrack-shaped pancakes wound with six-strand parallel conductors. The parallel conductors were transposed inside the windings, resulting in a uniform current distribution in each conductor. The motor utilized carbon fiber-reinforced plastic (CFRP) for the casing instead of stainless steel for weight reduction. Foam insulation was adopted to further reduce the mass, in which an adiabatic material was wrapped around the external part of the CFRP casing. The armature coil was cooled using sub-cooled liquid nitrogen (LN2), with high electrical insulation and a stable liquid phase. In contrast, the field coil was cooled by utilizing helium gas instead of LN2 because sealing the LN2 with a magnetic fluid seal is challenging. The motor was tested in a synchronous generator mode and subsequently rotated by utilizing three bipolar power supplies. The motor successfully rotated at 441 rpm when the field current was 72 A, the armature current was 103 Arms, and the frequency was 7.35 Hz.

Cerebral venous sinus thrombosis is rare and might be overlooked by healthcare providers. It often occurs in the transverse sinuses, superior sagittal sinus, and the vein of Trolard. Sphenoparietal sinus (SPS) and/or superficial middle cerebral vein (SMCV) thrombosis is rare and only 12 cases reported in the literature.

AbstractThe effect of TiC and NbC carbides on creep life has been investigated for 321HTB and 347HTB steels at 600–750°C for about 20–200,000 h. The creep data for 304HTB steel are used as reference data. The precipitation hardening is larger for the 321HTB than for the 347HTB at short times during creep. Then the reduction of precipitation hardening due to coarsening of TiC and NbC carbides takes place for up to long times, which is less significant in the 321HTB than in the 347HTB. The smaller coarsening rate of the TiC carbides than the NbC carbides during creep is discussed on the base of a rate equation for diffusion-controlled Ostwald ripening.

Objective: To investigate the relationship of dental status to food diversity among older Japanese. Design and Setting: A community-based cross-sectional study conducted in the town of Tosa, Kochi Prefecture, Japan. Methods: The study participants were 252 Japanese (84 men and 168 women, average age 81.2 years) and dentate participants were classified into three groups: 1-9 teeth, 10-19 teeth and 20 or more teeth. Food diversity was assessed as a validated measure of dietary quality using the 11-item Food Diversity Score Kyoto (FDSK-11), which evaluates frequency of consumption of II main food groups. Multivariable analysis of the differences in FDSK-11 score ranging from 0 to 11, with a higher score indicating greater food diversity, among the three dental status groups was conducted using general linear models. All the performed analyses were stratified by gender. Results: There was no association between dental status and food diversity score in models for men. In contrast, women with <9 teeth and with 10-19 teeth had significantly lower FDSK-11 scores than women with ≥20 teeth after adjusting for confounders (p<0.001 and p=0.009, respectively). Additionally, there was a trend toward lower scores for FDSK-11 with fewer teeth (p=0.001). Conclusion: A less varied diet, as indicated by low FDSK-11 score, was observed in female participants with fewer teeth. Tooth loss was associated with poor diet quality among older Japanese women. [ABSTRACT FROM AUTHOR]

The article discusses a modified cone jolt test used by researchers at Western Michigan University to compare gravity and aeration sand filling technique. It offers information on the modifications in the cone jolt toughness test over the last three years, including the ability to monitor changes in green sand properties caused by small changes in clay and moisture levels. Information is provided on the laboratory procedure used at the university to perform the cone jolt test.

A novel nano-sized Al2O3/carbon cluster composite materials with and without doping of Pt nanoparticles are successfully prepared for the first time. The newly synthesized composites indeed very effective to split the water and produce H2and O2with the [H2]/[O2] ratios of ca.2.under visible light irradiation.

Alternating stacks of metal and dielectric films with nano-hole arrays, called fishnet structures, control the propagation of electromagnetic waves. In such a structure, changing a dimension or a shape, especially the change in shape of nanoholes, affect propagation constants. In this study, we report the dispersivity of fishnet structures is controllable with different hole shapes, by measuring the interferometric fringe in various wavelengths. Two structures were fabricated, which consist of five alternating stacks of aluminum and silicon dioxide with nano-hole arrays. The holes in one of the structures are circular with diameters of 500nm, and the other are square with 500nm sides. The lattice constant in each case is 1,000nm. Since fishnet structures are wavelength-dependent structures, the variable-wavelength interferometric microscope was set up. The phase shift of the circular hole and the square hole fishnet were about 110 degrees and 85 degrees, respectively, within a tunable wavelength from 1,470nm to 1,545nm. These values were equivalent to a refractive-index-change of 0.8 and 0.6, respectively. From these results, fishnet structures indicate high dispersivity within target wavelengths. The dispersion of fishnet structure can be controlled by the shape of the hole.

Objective: The purpose of this study was to evaluate the relationship between bone fragility of the mandibular inferior cortex and tooth loss in older adults by accounting for periodontal disease and bone metabolism markers. Research Design: A total of 177 subjects aged 77 years participated in this study. We counted the number of remaining teeth. The mandibular cortex condition was examined using the mandibular inferior cortex classification (MICC) on dental panoramic radiographs. The mandibular inferior cortex was detected on both sides of the mandible, distally from the mental foramen (CI, normal; C2, mild/moderate erosion; C3, severe erosion). Multiple linear regression analysis was performed to assess the relationship between the mandibular cortex condition with the MICC and the number of remaining teeth after controlling for confounding factors such as gender, the percentage of sites with >4 mm clinical attachment levels, and serum osteocalcin levels. Results: The mean ± SD number of remaining teeth of MICC Cl, C2 and C3 were 20.7±7.5, 14.6±8.1 and 4.0±0.0 for males, and MICC Cl, C2, and C3 were 21.7±7.6, I7.2±8.O, and 16.2±10.4 for females. The MICC was significantly associated with the number of remaining teeth using multiple linear regression analysis (beta= -0.21, p=0.031 ). Conclusion: This study suggests that there is a relationship between bone fragility of the mandibular inferior cortex and tooth loss related to periodontal disease. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to evaluate the relationship between bone fragility of the mandibular inferior cortex and tooth loss in older adults by accounting for periodontal disease and bone metabolism markers. Research Design: A total of 177 subjects aged 77 years participated in this study. We counted the number of remaining teeth. The mandibular cortex condition was examined using the mandibular inferior cortex classification (MICC) on dental panoramic radiographs. The mandibular inferior cortex was detected on both sides of the mandible, distally from the mental foramen (CI, normal; C2, mild/moderate erosion; C3, severe erosion). Multiple linear regression analysis was performed to assess the relationship between the mandibular cortex condition with the MICC and the number of remaining teeth after controlling for confounding factors such as gender, the percentage of sites with >4 mm clinical attachment levels, and serum osteocalcin levels. Results: The mean ± SD number of remaining teeth of MICC Cl, C2 and C3 were 20.7±7.5, 14.6±8.1 and 4.0±0.0 for males, and MICC Cl, C2, and C3 were 21.7±7.6, I7.2±8.O, and 16.2±10.4 for females. The MICC was significantly associated with the number of remaining teeth using multiple linear regression analysis (beta= -0.21, p=0.031 ). Conclusion: This study suggests that there is a relationship between bone fragility of the mandibular inferior cortex and tooth loss related to periodontal disease. [ABSTRACT FROM AUTHOR]

The phase transformation behavior of 9Cr–3W–3Co–VNb steels with boron contents of 47 and 130 ppm has been investigated using differential thermal analysis (DTA). In our DTA experiments, disk-shaped samples were normalized and then tempered at temperatures between 10 and −50 C from the ferrite-to-austenite transformation temperature (Ac1) at a rate of 30 C/min. The measured Ac1 temperatures for 47 ppm B steel and 130 ppm B steel were 878 and 884 C, respectively. The general features of the phase transformation behavior and the changes in hardness with tempering temperature for these boron containing steels were almost identical, irrespective of the boron content. In the DTA cooling curves during tempering at temperatures between −30 and 10 C from the Ac1 temperatures, an exothermic peak due to the formation of fresh martensite was observed and the peak area increased with increasing tempering temperature. The Vickers hardness values measured after the DTA experiments decreased gradually with increasing tempering temperature, reaching a minimum value of about 180 HV around Ac1−40 C, and then increased markedly, reaching a value of about 350 HV at Ac1+10 C.

We have fabricated high-quality CuGaSe2 thin films using ionized Ga precursors. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy. The grain size and the crystallinity of CuGaSe2 films using ionized Ga precursors were larger than those of the films using unionized Ga precursors. It was found from the experiments that the migration energy of Ga precursors played an important role in the crystal growth for high-quality CuGaSe2 films. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Previous in vitrostudies demonstrated that thrombopoietin (TPO) acts on platelets to activate a variety of intracellular signaling pathways and to enhance platelet sensitivity to multiple agonists. Little is known, however, about whether TPO exerts prothrombotic effects in vivo. The aim of this study was to examine the effects of pegylated recombinant human megakaryocyte growth and development factor (PEG‐rHuMGDF), a pegylated N‐terminal domain of human TPO, in a rat model of venous thrombosis. A microthrombus was photochemically induced on the vessel wall of a mesenteric venule, but the vessel was not occluded by it. A single intravenous injection of PEG‐rHuMGDF (3 μg kg−1) after the thrombus generation into normal rats enhanced the thrombus size, resulting in transient thrombotic occlusion in the majority of rats. Stimulatory effects on thrombus growth were also observed following administration of glycosylated recombinant human full‐length TPO (6 μg kg−1). In rats rendered thrombocytopenic by total body irradiation, however, PEG‐rHuMGDF, even at 300 μg kg−1, did not induce a significant increase in thrombus size or thrombotic occlusion. Platelets from thrombocytopenic rats had decreased surface levels of c‐Mpl and decreased sensitivity to PEG‐rHuMGDF in an in vitroaggregation response. Thus, decreased prothrombotic effects of PEG‐rHuMGDF in thrombocytopenic rats might be the result not only of low platelet counts but also of decreased platelet reactivity to PEG‐rHuMGDF. These results indicate that PEG‐rHuMGDF has little effect on venous thrombus formation in thrombocytopenic states associated with high endogenous TPO levels.

o-Cyano-β,β-difluorostyrenes react with organolithiums selectively at the cyano carbon to generate the corresponding sp² nitrogen anions, which in turn undergo intramolecular replacement of the vinylic fluorine to afford 3-fluoroisoquinolines. Similarly, the reaction of β,β-difluoro-o-isocyanostyrenes with organomagnesiums or -lithiums generates the corresponding sp² carbanions on the isocyano carbon. Subsequent cyclization via substitution of the fluorine leads to 3-fluoroquinolines.

A supersonic plasma is produced quasi-steadily by use of a magneto-plasma-dynamic arcjet (MPDA) in various shapes of an external magnetic field configuration. An ion acoustic Mach number Miof the plasma flow is limited to be nearly unity in a uniform magnetic field configuration, while it increases up to almost 3 in a divergent magnetic nozzle configuration. Spatial variations of Miis well predicted by an isentropic model for a compressible gas. The Mach number decreases in the far downstream region due to charge-exchange collisions between flowing ions and neutral atoms which are produced through surface-recombination on the end wall. Ion heating of the fast flowing plasma has been successfully demonstrated for the first time. This success is mainly due to the plasma density is high enough to reduce the penetration of neutral gases which cause the charge-exchange energy loss. It is found that an asymmetric RF wave with an azimuthal mode number m= ± 1 is most effective to heat the ions.

A feeder-independent cloned trophoblast cell line, HTS-1, was established from a mature placenta of Shiba goat (Capra hircus). During the growth phase, single HTS-1 cells exhibited ruffled membranes or lamellipodia often accompanied by elongated cell shape, indicating highly motile nature of the cells. At or near confluence, HTS-1 cells formed monolayers with few sign of cellular overlapping. Binucleate cells were found at a high frequency especially in the peripheral regions of monolayers. In small colonies and the monolayers, majority of HTS-1 cells assumed polygonally shaped cobble-stone like morphology characteristic to epithelial cells, although considerable variations in cellular morphology were observed despite of repeated cloning. Time-lapse video recordings of HTS-1 cells during culture revealed that not only the small colonies but also the monolayers near or at confluence were remarkably motile, often causing extreme elongation of the cells within them. The extremely plastic nature of HTS-1 cells in vitro is likely to be the reflection of the extraordinary capacity of caprine trophoblast cells to be stretched to extreme thiness in vivo as shown by electron microscopy. HTS-1 cells cultured on matrigel are highly invasive, and express MT1-MMP which, in the mouse, has been known to be expressed at the invasive edge of trophoblast both in vitro and in vivo. HTS-1 cells express placental lactogen (PL) and interferon-τ (IFNτ), as confirmed by immunocytochemistry, Western blotting and RT-PCR analysis. Both PL and IFNτ expression in the cells appeared to be down-regulated by cell-cell contact. In the medium conditioned by HTS-1 cells, the presence of secretory form of PL and IFNτ was confirmed by Western blotting. The HTS-1 cell line will serve as a useful in vitro model for the analysis of the molecular and/or cellular mechanisms underlying synepitheliochorial placentation in bovidae animals.

We studied the changes in vascular smooth muscle (VSM) cell tone during the adaptation of rat common carotids to induced hypertension. Hypertension was induced in 8 week old male Wistar rats by total ligation of the aorta between the two kidneys. Mean blood pressure increased abruptly from 92±2 mm Hg (mean±SE) to 145±4 mm Hg and remained constant thereafter. Rats were sacrificed 2, 4, 8, and 56 days after surgery and the left common carotid artery was excised for analysis. Pressure-diameter curves were measured in vitrounder normal, maximally contracted, and totally relaxed VSM. The VSM tone was analyzed in terms of its basal tone (active stress at low strains) and its myogenic tone (increase in active stress at high strains). Our results show that the capacity of the VSM to develop maximal active stress is not altered in hypertension. Basal tone, however, increases rapidly in the acute hypertension phase (2–8 days postsurgery) and drops to nearly control values at 56 days postsurgery. Also, the onset of myogenic response decreases to lower strains following the step change in pressure, to be restored back to control levels at 56 days postsurgery. We conclude that VSM adaptation is most significant in the acute hypertension phase and acts as a first, rapid defense mechanism for the arterial wall. The VSM tone returns back to normal levels once the slower geometrical and structural remodeling is developed sufficiently to restore the biomechanical environment and function of the arterial wall to control levels. © 2002 Biomedical Engineering Society. PAC2002: 8719Rr, 8719Ff, 8719Uv

A highly active solid superacid of sulfated tin oxide was prepared from tin oxide gel, which was precipitated by the hydrolysis of SnCl4 and washed with aqueous ammonium acetate solution, followed by exposure to aqueous sulfuric acid and calcining. Differencial thermal analysis suggested that the acetate ion remaining on the surface was replaced with sulfate ion. The acid strength of the sulfated tin oxide estimated by temperature-programmed desorption using argon was higher than that of sulfated zirconia, a well-known solid superacid, the activation energy of Ar desorption by the former being 10.6 kJ mol^-1 in comparison with 9.3 kJ mol^-1 by the latter. The sulfated tin oxide showed activities much higher than those of the sulfated zirconia for the skeletal isomerization of n-pentane, the Mukaiyama aldol condensation of 1-trimethylsilyloxy-1-cyclohexene with benzaldehyde, and the benzoylation of toluene with benzoic anhydride.

Superplastic behaviour in ceramics at high temperature is predicted in the present study by using a modified constitutive equation for superplasticity that incorporates the rate of grain growth. The equation explains the high speed deformation, ɛ · = 10-3s-1, of an Al2O3-3TiC (wt-%) composite caused at elevated temperature (1600°C). The equation also provides an analysis of both variations in n value for 3Y–TZP and increased flow stress for liquid phase sintered SiC in the slow strain rate region, in which grain growth plays an important role. A new concept for developing superplastic ceramics is provided.

The biomechanical adaptation of the arterial wall to hypertension has been studied extensively in recent years; however, the exact biomechanical contribution of vascular smooth muscle cells (VSMCs) during the adaptation process in conduit vessels is not known. We induced hypertension in 8 wk old Wistar rats by total ligation of the aorta between the two kidneys. Mean blood pressure increased from 92 ± 2 (mean ± SE)mm Hg to approximately 150 mm Hg. Rats were sacrificed 2, 4, and 8 d after surgery and the left common carotid artery was excised for analysis. Wall thickness increased by 18% in 8 d and the opening angle by 32% in 4 d. The elastic properties were measured under normal VSMC tone (i.e., the amount of VSMC tone under normal conditions also called basal VSMC tone or normal resting VSMC tone), under maximally contracted VSMC (NE, 5 × 10 -7mol/L) and under totally relaxed VSMC conditions (papaverine, 10-4mol/L). The most pronounced modifications were the changes in elastic properties related to normal VSMC tone. The functional contraction ratio at 100 mm Hg, defined as the relative contraction under normal conditions (normal VSMC tone), increased by 439% 4 d after the induction of hypertension. The total contraction capacity of the VSMC increased by 38% within 8 d. The changes in normal VSMC tone led to important changes in the mechanical properties of the arterial wall. Under normal VSMC conditions, compliance at mean pressure (148 mm Hg) increased by 159% within 8 d, whereas in the absence of VSMC tone, compliance did not increase significantly. We conclude that in conduit vessels, the VSMC, which is the sensing and effecting element of the adaptation process, is subjected to large-scale changes during the early phase of arterial adaptation to acute hypertension. © 2001 Biomedical Engineering Society. PAC01: 8719Rr, 8719Ff, 8719Uv, 8717-d

Thrombopoietin (TPO) is a cytokine that primarily stimulates megakaryocytopoiesis and thrombopoiesis. TPO has a unique C-terminal tail peptide of about 160 amino acids that consists mostly of hydrophilic residues and contains six N-linked sugar chains. In order to investigate the biological function of the C-terminal domain, two series of mutations were performed. One is systematic truncation from the C terminus. Another is elimination of N-glycosylation sites in the C-terminal domain by Asn to Gln mutations. After the mutant proteins were expressed by mammalian cells, it was found that the elimination of the N-linked sugar sites did not affect the biological activity, whereas truncation of the C-terminal domain resulted in elevation of in vitro activity up to 4-fold. The C-terminal peptide itself was found to inhibit the in vitro activity. Moreover, both the C-terminal truncation and the elimination of the N-glycosylation sites decreased the secretion level progressively down to (1)/(10) that of wild type, and the amount of the mutant left in the cell increased. The N-glycosylation in the C-terminal region was found to be important for secretion of TPO. Among six N-glycosylation sites in the C-terminal region, two locations, Asn-213 and Asn-234, were found to be critical for secretion, and two other locations, Asn-319 and Asn-327, did not affect the secretion.

A rat pheochromocytoma cell line (PC12) transfected with ganglioside GD3 synthase gene showed a marked change in the ganglioside profile and enhanced proliferation and no response of neurite extension to nerve growth factor (NGF) stimulation. In these transfectant cells, a continuous phosphorylation of TrkA and the activation of ERK1/2 without NGF treatment were observed. Proliferation inhibition experiments with kinase inhibitors such as herbimycin A, K-252a, and PD98059 revealed that the enhanced proliferation was actually due to the activation of the Ras/MEK/ERK pathway. A TrkA dimer was detected in the GD3 synthase transfectant cells regardless of NGF treatment by cross-linking and immunoblotting. The increased expression of GD1b and GT1b in these transfectant cells might induce the conformational change of TrkA to form a dimer and to be activated continuously. These results may indicate regulatory roles of gangliosides in cell proliferation under physiological and malignant processes.

At the late phase of megakaryocytopoiesis, megakaryocytes undergo endomitosis, which is characterized by DNA replication without cell division. Although a number of cell cycle regulatory molecules have been identified, the precise roles of these molecules in megakaryocytic endomitosis are largely unknown. In a human interleukin-3-dependent cell line transfected with the thrombopoietin (TPO) receptor c-mpl (F-36P-mpl), either treatment with TPO or the overexpression of activated ras (Ha-Ras(G12V)) induced megakaryocytic maturation with polyploid formation. We found that TPO stimulation or Ha-Ras(G12V) expression led to up-regulation of cyclin D1, cyclin D2, and cyclin D3 expression. In addition, expression levels of cyclin A and cyclin B were reduced during the total course of both TPO- and Ha-Ras(G12V)-induced megakaryocytic differentiation, thereby leading to decreased cdc2 kinase activity. Neither the induced expression of cyclin D1, cyclin D2, or cyclin D3 nor the expression of a dominant negative form of cdc2 alone could induce megakaryocytic differentiation of F-36P-mpl cells. In contrast, overexpression of dominant negative cdc2 together with cyclin D1, cyclin D2, or cyclin D3 facilitated megakaryocytic differentiation in the absence of TPO. These results suggest that both D-type cyclin expression and decreased cdc2 kinase activity may participate in megakaryocytic differentiation.

Abstract: Mechanical properties of living endothelial cells in the abdominal aortas and in the medial and lateral wall of aortic bifurcations obtained from rabbits were determined by means of an atomic force microscope (AFM), focusing on the locational differences. Force (F)-indentation (δ) curves of the cells were expressed by an exponential function: F=a(exp(bδ)−1), where a and b are constants. The parameters b and c(=ab) represent the rate of modulus change and initial modulus, respectively. The slope of F-δ curves a and the parameter c were higher in the medial wall than in the other sites, which is attributable to abundant stress fibres in endothelial cells in the medial wall. There were no differences in the parameter b among the three locations. These results indicate that endothelial cells are stiffer in the medial wall of aortic bifurcation than in the other regions.

T cell development and function in complex ganglioside-lacking (GM2/GD2 synthase gene-disrupted) mice were analyzed. GM1, asialo-GM1, and GD1b were representative gangliosides expressed on T cells of the wild type mice and completely deleted on those of the mutant mice. The sizes and cell numbers of the mutant mice spleen and thymus were significantly reduced. Spleen cells from the mutant mice showed clearly reduced proliferation compared with the wild type when stimulated by interleukin 2 (IL-2) but not when treated with concanavalin A or anti-CD3 cross-linking. Expression levels of IL-2 receptor alpha, beta, and gamma were almost equivalent, and up-regulation of alpha chain after T cell activation was also similar between the mutant and wild type mice. Activation of JAK1, JAK3, and SAT5 after IL-2 treatment was reduced, and c-fos expression was delayed and reduced in the mutant spleen cells, suggesting that the IL-2 signal was attenuated in the mutant mice probably due to the modulation of IL-2 receptors by the lack of complex gangliosides.

A novel member of the human CMP-NeuAc:beta-galactoside alpha2, 3-sialyltransferase (ST) subfamily, designated ST3Gal VI, was identified based on BLAST analysis of expressed sequence tags, and a cDNA clone was isolated from a human melanoma line library. The sequence of ST3Gal VI encoded a type II membrane protein with 2 amino acids of cytoplasmic domain, 32 amino acids of transmembrane region, and a large catalytic domain with 297 amino acids; and showed homology to previously cloned ST3Gal III, ST3Gal IV, and ST3Gal V at 34, 38, and 33%, respectively. Extracts from L cells transfected with ST3Gal VI cDNA in a expression vector and a fusion protein with protein A showed an enzyme activity of alpha2, 3-sialyltransferase toward Galbeta1,4GlcNAc structure on glycoproteins and glycolipids. In contrast to ST3Gal III and ST3Gal IV, this enzyme exhibited restricted substrate specificity, i.e. it utilized Galbeta1,4GlcNAc on glycoproteins, and neolactotetraosylceramide and neolactohexaosylceramide, but not lactotetraosylceramide, lactosylceramide, or asialo-GM1. Consequently, these data indicated that this enzyme is involved in the synthesis of sialyl-paragloboside, a precursor of sialyl-Lewis X determinant.

Expression cloning of a cDNA for the alpha2,3-sialyltransferase (GM3 synthase) (EC 2.4.99.-) gene was performed using a GM3-lacking mouse fibroblast line L cell and anti-GM3 monoclonal antibody. Plasmids from a cDNA library generated with poly(A)+ RNA of a mouse fibrosarcoma line CMS5j and pdl3027 (polyoma T antigen) were co-transfected into L cells. The isolated cDNA clone pM3T-7 predicted a type II membrane protein with 13 amino acids of cytoplasmic domain, 17 amino acids of transmembrane region, and a large catalytic domain with 329 amino acids. Introduction of the cDNA clone into L cells resulted in the neo-synthesis of GM3 and high activity of alpha2,3-sialyltransferase. Among glycosphingolipids, only lactosylceramide showed significant activity as an acceptor, indicating that this gene product is a sialyltransferase specific for the synthesis of GM3. An amino acid sequence deduced from the cloned cDNA showed the typical sialyl motif with common features among alpha2,3-sialyltransferases. Among various mouse tissues, brain, liver, and testis showed relatively high expression of a 2.3-kilobase mRNA, whereas all tissues, more or less, expressed this gene.

Angiotensin II (Ang II) type 2 receptor (AT2) has been shown to counteract the type 1 receptor (AT1)-mediated biological actions of Ang II in the cardiovascular system. The biological significance of AT2 receptor in the adrenals however remains unknown. In the present study, we investigated the roles of ATI and AT2 receptor subtypes in the regulation of aldosterone secretion and DNA synthesis in bovine adrenocortical zona glomerulosa cells in vitro. Ang II (1 µmol/l)-stimulated aldosterone secretion was completely suppressed by AT1 antagonist CV-11974 but not affected by AT2 receptor antagonist PD-123319. Effects on DNA synthesis were investigated by determining the incorporation of BrdU into the nuclei of the cultured zona glomerulosa cells. Ang II (1 µmol/l)-stimulated DNA synthesis of the cells was also completely suppressed by CV-11974 but not by PD-123319. These results suggest that AT1 receptor but not AT2 receptor is the predominant receptor subtype which mediates the Ang II-stimulated aldosterone secretion and cell growth in bovine adrenocortical cells.