A myeloid cell line, designated PL-21, was established from the peripheral blood of a patient with acute promyelocytic leukemia. The PL-21 cell line grew in single-cell suspension, with a doubling ...time of 48-64 hr, and consisted of promyelocytes with fine immature nuclei and prominent azurophilic granules in the cytoplasm. PL-21 cells were positive for peroxidase, naphthol AS-D chloroacetate esterase, and Sudan Black B staining. Under the usual culture conditions, a small proportion of these cells differentiated into mature granulocytes, and this differentiation was enhanced by the addition of dimethyl sulfoxide in the culture medium. PL-21 cells had receptors for the Fc portion of IgG and complement, intracytoplasmic lysozyme and phagocytic activity, but lacked Epstein-Barr virusassociated nuclear antigen. Chromosome analysis of this cell line revealed a human male polyploid karyotype with 13q + and double minute chromosomes. This new myeloid cell line may provide useful material for the study of proliferation and differentiation of human leukemia cells.
To understand light-induced immune modulation in vivo, we evaluated the effect of nocturnal light exposure on splenic natural killer (NK) cell activity in rats. Nocturnal increases in the number and ...cytotoxic activity of NK cells were significantly suppressed under extended light exposure. Nocturnal increases in serum corticosterone levels were also suppressed by light exposure, suggesting that the light exposure-induced decrease in NK cell functions was not due to stress-induced glucocorticoid secretion in rats. These results suggest that nocturnal light exposure could profoundly affect NK cell functions perhaps through eye-brain hormonal modulation.
An electrostatic micromechanical switch that can conduct a logic operation with only one switch is proposed. This switch can perform an “AND” or an “OR” logic operation because it has two pairs of ...drive electrodes and its switching is controlled by the number of drive electrodes to which driving voltage is applied. A new beam layout makes it possible to decrease the driving voltage without increasing the switch area. The driving voltage can be reduced to 15 V when switch area is 60×70 μm
2. The switch, which can be fabricated by standard LSI processes, is ideal for making compact logic circuits for multichip modules (MCMs) on Si.
A 3/7-level mixed-mode algorithmic analog-to- digital converter (ADC) is proposed. The operation comprises six phases to obtain the 8-bit resolution. The 3-level mode is used in the first three ...phases for an accurate conversion, while the 7-level mode is used for the last three phases to improve the sampling speed. Transistor-level simulations assuming 0.18-mum CMOS technology with a supply voltage of 1.8 V are carried out to estimate the circuit performance. A signal-to-noise ratio of 48.1dB (ap7.7 bit) is obtained at a sampling frequency of 12.8 MHz, which is superior to the results obtained from conventional 3-level and 7-level algorithmic ADCs.
The thermal conductivity
κ
xx
is the difference between higher and lower temperature regions, because the spatially-resolved thermal conductivity
κ
xx(
r
)
is localized around the vortex core at ...lower temperature and delocalized at higher temperature. On one hand, much attention is focused on the spin and charge ordering around the vortex. When the antiferromagnetism appears around the core, the energy gap suppresses the density of states on the Fermi energy, and the zero-energy peak at the vortex core splits or vanishes. The
κ
xx
under the Néel temperature is suppressed by the antiferromagnetism. We solve the Bogoliubov–de Gennes equation self-consistently by two-dimensional extended Hubbard model including the repulsive interaction
U, and calculate the
κ
xx
on the basis of the linear response theory. The picture of the spatial variation of the thermal conductivity
κ(
r) through the spin resolved local DOS well explains recent experiments.
Six new sterols, 5α, 6α;8α, 9α-diepoxy-(22E, 24R)-ergost-22-ene-3β, 7α-diol (1), 5α, 6α;8α, 9α-diepoxy-(22E, 24R)-ergost-22-ene-3β, 7β-diol (2), 5α, 6α-epoxy-(22E, 24R)-ergosta-8, 22-diene-3β, ...7β-diol (3), (22E, 24R)-23-methylergosta-7, 22-diene-3β, 5α, 6β-triol (4), (22E, 24R)-23-methulergosta-7, 22-diene-3β, 5α, 6β, 9α-tetrol (5) and (24S)-ergost-7-ene-3β, 5α, 6β, 9α-tetrol (6), have been isolated from seven mushrooms, Amanita pantherina, Amantia virgineoides, Lactarius piperatus, Lyophyllum shimeji, Tricholoma portentosum, Hypsizigus marmoreus and Lentinula edodes together with eighteen known ones (7-24). The structures of these new compounds were elucidated on the basis of their spectral data.
New types of noncovalent ribozyme-mimics for site-selective RNA scission are prepared by combining metal ions with oligonucleotides bearing an acridine. Lanthanide(III) ions and various divalent ...metal ions (Zn(II), Mn(II), Cu(II), Ni (II), Co(II), Mg(II), and Ca(II)) are employed without being bound to any sequence-recognizing moiety. The modified oligonucleotide forms a heteroduplex with the substrate RNA, and selectively activates the phosphodiester linkages in front of the acridine. As a result, these linkages are preferentially hydrolyzed over the others, even though the metal ions are not fixed anywhere. The scission is efficient under physiological conditions, irrespective of the sequence at the target site. Site-selective RNA scission is also successful with the combination of an oligonucleotide bearing an acridine at its terminus, another unmodified oligonucleotide, and the metal ion. In a proposed mechanism, the acridine pushes the unpaired ribonucleotide out of the heteroduplex and changes the conformation of RNA at the target site for the sequence-selective activation.
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