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  • 1
    Electronic Resource
    Electronic Resource
    Cooperative foundation of colonies by unrelated foundresses in the antPolyrhachis moesta (1996)
    Springer
    Insectes sociaux 43 (1996), S. 217-226 
    Details
    ISSN: 1420-9098
    Keywords: Pleometrosis ; relatedness of cofoundresses ; Polyrhachis ; DNA fingerprinting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Field studies ofPolyrhachis moesta revealed that colonies were facultatively founded by more than one queen, even though each established colony was inhabited by only one queen with her workers. In pleometrotic colonies, it was found that cofoundresses frequently exhibited cooperative behaviors, including trophallaxis. The results of DNA fingerprinting showed that multiple foundresses were not genetically to one another. It seems that they aggregate randomly and independently of their relatedness. A discussion of the reasons why foundresses ofP. moesta do not aggregate preferentially with genetically related females.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01242573
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  • 2
    Electronic Resource
    Electronic Resource
    Three new mutations in the hepatocyte nuclear factor-1α gene in Japanese subjects with diabetes mellitus: clinical features and functional characterization (1999)
    Springer
    Diabetologia 42 (1999), S. 621-626 
    Details
    ISSN: 1432-0428
    Keywords: Keywords MODY ; HNF-1α ; insulin ; arginine ; mutation.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Aims/hypothesis. Mutations in the hepatocyte nuclear factor-1α gene are a common cause of the type 3 form of maturity-onset diabetes of the young. We examined the clinical features and molecular basis of hepatocyte nuclear factor-1α (HNF-1α) diabetes. Methods. Thirty-seven Japanese subjects with early onset Type II (non-insulin-dependent) diabetes mellitus and 45 with Type I (insulin-dependent) diabetes mellitus were screened for mutations in this gene. Functional properties of mutant HNF-1α were also investigated. Results. Three new mutations [G415R, R272C and A site of the promoter ( + 102G-to-C)] were found. Insulin secretion was impaired in the three subjects. Insulin and glucagon secretory responses to arginine in the subject with the R272C mutation were also diminished. Molecular biological studies indicated that the G415R mutation generated a protein with about 50 % of the activity of wild-type HNF-1α. The R272C mutation had no transactivating or DNA binding activity and acted in a dominant negative manner. The + 102 G-to-C mutation in the A site of the promoter activity was associated with an increase in promoter activity and it had 42–75 % more activity than the wild-type sequence. Conclusion/interpretation. Mutations in the HNF-1α gene may affect the normal islet function by different molecular mechanisms. [Diabetologia (1999) 42: 621–626]
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001250051204
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  • 3
    Electronic Resource
    Electronic Resource
    Fine structure of bovine morulae and blastocysts in vivo and in vitro (1999)
    Springer
    Anatomy and embryology 199 (1999), S. 519-527 
    Details
    ISSN: 1432-0568
    Keywords: Key words Morphology ; Embryo culture ; Lipid droplet ; Development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The ultrastructure of bovine morulae and blastocysts developed from in vitro-matured and -fertilized oocytes in a serum-supplemented medium was compared with that of morulae and blastocysts collected non-surgically from superovulated cows. In the in vivo-derived morulae, two characteristic cells types could be identified by the electron-density of their cytoplasm and by their ultrastructural features. One type appeared light in color with low electron-dense cytoplasm. These cells were located in the peripheral layer of the cluster of blastomeres, possessed numerous cellular organelles such as mitochondria and Golgi apparatus and had microvilli projecting into the perivitelline space. The other cell type was distinguished by cytoplasm that stained more densely than that of the lighter-appearing cells. The darker-appearing cells generally possessed fewer organelles than the lighter cells, but many lysosome-like structures were present in the cytoplasm. The in vitro-developed morulae also contained two types of cells similar to those observed in the in vivo morulae. However, most of the in vitro-developed cells possessed numerous lipid droplets and contained fewer lysosome-like structures than the cells of the in vivo-derived morulae. The blastocysts, both in vivo and in vitro, showed a clear differentiation of trophoblast cells and inner cell mass (ICM)-cells. In the in vivo-derived blastocyst, the apical membrane of trophoblast cells was covered with large, numerous microvilli and well-developed junctional complexes were observed. Lipid droplets were present in the cytoplasm of trophoblast and ICM-cells but were not abundant. In vitro-developed blastocysts showed less well-developed junctional complexes between trophoblast cells, less well-developed apical microvilli on the trophoblast cells, and contained large numbers of lipid droplets. This accumulation of lipid droplets was higher in the trophoblast cells than in the ICM-cells. The zonae pellucidae of in vitro-developed embryos were thinner than that of the in vivo-derived embryos. This study demonstrates conspicuous differences in the ultrastructural features between the in vivo-derived and in vitro-developed embryos, suggesting that the ultrastructure may reflect the various physiological anomalies observed in previous studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004290050249
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  • 4
    Electronic Resource
    Electronic Resource
    Regulation of Na-K-ATPase Activity in the Proximal Tubule: Role of the Protein Kinase C Pathway and of Eicosanoids (1996)
    Springer
    The journal of membrane biology 152 (1996), S. 235-243 
    Details
    ISSN: 1432-1424
    Keywords: Key words: Na:K pump — Dopamine — Parathyroid hormone — Phospholipase C — Protein kinase C — Cytochrome P450-monooxygenase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract. To evaluate further the signal transduction mechanisms involved in the short-term modulation of Na-K-ATPase activity in the mammalian kidney, we examined the role of phospholipase C-protein kinase C (PLC-PKC) pathway and of various eicosanoids in this process, using microdissected rat proximal convoluted tubules. Dopamine (DA) and parathyroid hormone (either synthetic PTH1-34 or PTH3-34) inhibited Na-K-ATPase activity in dose-dependent manner; this effect was reproduced by PKC530-558 fragment and blocked by the specific PKC inhibitor calphostin C, as well as by the PLC inhibitors neomycin and U-73122. Pump inhibition by DA, PTH, or arachidonic acid, and by PKC activators phorbol dibutyrate (PDBu) or dioctanoyl glycerol (DiC8) was abolished by ethoxyresorufin, an inhibitor of the cytochrome P450-dependent monooxygenase pathway, but was unaffected by indomethacin or nordihydroguaiaretic acid, inhibitors of the cyclooxygenase and lipoxygenase pathways of the arachidonic acid cascade, respectively. Furthermore, each of the three monooxygenase products tested (20-HETE, 12(R)-HETE, or 11,12-DHT) caused a dose-dependent inhibition of the pump. The effect of DA, PTH, PDBu or DiC8, as well as that of 20-HETE was not altered when sodium entry was blocked with the amiloride analog ethylisopropyl amiloride or increased with nystatin. We conclude that short-term regulation of proximal tubule Na-K-ATPase activity by dopamine and parathyroid hormone occurs via the PLC-PKC signal transduction pathway and is mediated by cytochrome P450-dependent monooxygenase products of arachidonic acid metabolism, which may interact with the pump rather than alter sodium access to it.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002329900101
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  • 5
    Electronic Resource
    Electronic Resource
    TNF-α, RANTES, and MCP-1 are major chemoattractants of murine Langerhans cells to the regional lymph nodes (1998)
    Oxford, UK : Blackwell Publishing Ltd
    Experimental dermatology 7 (1998), S. 0 
    Details
    ISSN: 1600-0625
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: We have previously reported that lymph node cells generated chemotactic factors for Langerhans cells (LCs) in the induction phase of contact dermatitis. In order to clarify the chemotactic factors involved in migration to the regional lymph nodes, we investigated the migratory activity of murine LCs toward several cytokines and chemokines in vitro. One-day cultured LC-enriched epidermal cells were added to the upper compartment of a modified Boyden chamber and cytokines were added to the lower compartment. We counted dendritic cells migrated to the lower chamber as LCs under phase contrast microscopy. About 99% of migrated dendritic cells were positively reacted with anti-Iad and NLDC145 antibodies and considered to be LCs. We could detect LC migration more accurately by this direct examination than by counting the migrated cells in the filter membrane of a Boyden chamber. In our system, migration of murine epidermal LCs was stimulated by TNF-β, RANTES and MCP-1, but not by GM-CSF, IL-1β, IL-4, and IL-6. TNF-α induced LC migration at concentrations from 4X103 U/ml to 5X104 U/ml. RANTES at concentrations from 10 to 100 ng/ml and MCP-1 a concentration of 100 ng/ml induced LC migration in a dose-dependent manner. These data confirmed that TNF-α, RANTES, and MCP-1 induced LC migration from epidermis during contact sensitization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-0625.1998.tb00300.x
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  • 6
    Electronic Resource
    Electronic Resource
    Interferon-gamma differentially regulates CD80 (B7-1) and CD86 (B7-2/B70) expression on human Langerhans cells (1997)
    Oxford, UK : Blackwell Publishing Ltd
    British journal of dermatology 136 (1997), S. 0 
    Details
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: CD80 (B7-1) and CD86 (B7-2/B70) have recently been identified in cultured human Langerhans cells (LCs), although their role and regulatory properties remain unclear. We present our comparison of the expression of the molecules, mRNAs and the function between CD80 and CD86 in human LCs treated by interferon γ (IFN-γ). We examined the regulatory properties of CD80 and CD86 expression in human LCs pretreated with IFN-γ. Flow cytometric analysis indicated that the mean fluorescence intensity of CD86 but not CD80 was enhanced. However, the percentage modulation of both CD80 and CD86 positive cells were significantly up-regulated in a dose-dependent manner, after 48-h culturing with IFN-γ. The regulatory properties of CD80 and CD86 mRNA expressions in human LC were studied using polymerase chain reaction methods. We found that both CD80 and CD86 mRNA of enriched LCs following IFN-γ pretreatment for 12 h were higher than those without pretreatment.We have demonstrated that the primary allogeneic mixed epidermal cell-lymphocyte reaction induced by human LCs treated by IFN-γ increased in a dose-dependent manner. There was a 61.5% inhibition by anti-CD86 monoclonal antibody and a 32.5% inhibition by anti-CD80 monoclonal antibody. These data indicate that the CD80 and CD86 expression of human LCs may be differently regulated by IFN-γ.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2133.1997.01843.x
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  • 7
    Electronic Resource
    Electronic Resource
    Heat capacity of ternary compounds RNiGe(R=Gd, Dy, Er, and Y) (1995)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 78 (1995), S. 7410-7412 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The heat capacity of the ternary compounds RNiGe(R=Er, Dy, Gd, and Y) was studied in the temperature range between 2 and 40 K. From the heat capacity curves, Néel temperatures are found to be 3.3, 7.4, and 10.7 K for ErNiGe, DyNiGe, and GdNiGe, respectively. The heat capacity of YNiGe was well fitted with an average Debye temperature of 272 K in the temperature range between 2 and 40 K. The changes of magnetic entropy indicate a strong influence of the crystal field on the Er+3 and Dy+3 ion in ErNiGe and DyNiGe compounds. These results suggest the possibility of using these compounds as magnetic regenerator materials near the temperature of 4.2 K. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.360395
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  • 8
    Electronic Resource
    Electronic Resource
    Detection of shear wave in ultrasonic range by using a laser Doppler vibrometer (1998)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 69 (1998), S. 2572-2573 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A laser Doppler vibrometer is used to measure shear waves propagating through solids in the ultrasonic frequency range. The laser Doppler vibrometer detects translational motion of small spherical lenses mounted on a solid surface. Stacking of wave-form signals increases the signal-to-noise ratio. Wave motion on a solid surface can be obtained from the surface vibrations measured at different incident angles of a laser beam. The observed longitudinal and shear wave amplitudes from a thickness-dilation-mode transducer agreed fairly well with the calculated amplitudes modeled by a piston force source. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1148961
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  • 9
    Electronic Resource
    Electronic Resource
    Structure and magnetic properties of Sm3(Fe, V)29NX (1999)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 85 (1999), S. 4675-4677 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The crystal structure and magnetic properties of Sm3(Fe, V)29NX compounds were investigated. It was found that the novel nitride, Sm3(Fe, V)29N2, is more stable than Sm3(Fe, V)29N4 in the atmosphere with low nitrogen pressure. The x-ray and electron diffraction studies show that the nitrides retain the same crystal structure as Sm3(Fe, V)29. The lattice parameters of Sm3(Fe, V)29N2 are a=1.084 nm, b=0.870 nm, c=0.985 nm, and β=97.06°. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.370444
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  • 10
    Electronic Resource
    Electronic Resource
    Enhanced hydrogenation and acceptor passivation in Si by pressurized water boiling (1995)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 67 (1995), S. 64-66 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: It has been shown that a pressurized water boiling (PWB) at 2 atmospheric pressures and 120 °C in an autoclave vessel accelerates significantly hydrogenation and neutralization of B acceptors in Si. Compared with boiling at atmospheric pressure, PWB reduces more the free-hole IR absorption and increases more the sheet resistivity in B implanted p+ layer on n-type substrate. An IR absorption of B–H stretching vibration (∼1907 cm−1) has been detected at 16 K for a p+ layer which was PWB processed for only 6 h. Concentration increase of H-related species in water and faster diffusion of H in Si at higher temperature may be the cause. In contrast with other hydrogenation techniques, water boiling hardly passivates donors in Si even for 10 h PWB. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.115494
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