Production of anti-self-H-2 antibodies by C3D2F1 mice hyperimmune to L cell/L1210 hybrids and L1210 leukemia cells

During the course of immunization of (C3H × DBA/2)F₁ mice (genotype H-2^k/b) with L cell (H-2^k/k)/L1210 leukemia cell (H-2^d/d) hybrids and L1210 leukemia cells, some of them produced a good titer of anti-self-H-2 (H-2^d) antibodies. Antigens recognized by this anti-self-H-2 antiserum were shown to be controlled by the H-2K-IA-IB-IJ-IE subregions of the H-2^d but not H-2^k nor H-2^b haplotypes of parental as well as F₁ origins and to have a tissue distribution identical to that of class 1 H-2 (H-2K/D) antigens.     

Systemic amyloidosis in transgenic mice carrying the human mutant transthyretin (Met 30) gene

To analyze the pathologic processes of amyloid deposition in type I familial amyloidotic polyneuropathy (FAP), mice were made transgenic by introducing the human mutant transthyretin (TTR) gene(MT-hMet 30). An inbred strain of mouse, C57 BL/6, was chosen. Transgenic mice were killed using ether anesthesia at 3-mo intervals up to 24 mo after birth. In these transgenic mice, amyloid deposition started in the gastrointestinal tract, cardiovascular system, and kidneys and extended to various other organs and tissues with advancing age. The pattern of amyloid deposition was similar to that observed in human autopsy cases of FAP, except for its absence in the choroid plexus and in the peripheral and autonomic nervous systems. We extracted the amyloid fibrils from kidneys of these mice with a human mutant TTR gene and analyzed them immunochemically and electronmicroscopically. Deposited amyloid was shown to be composed of human mutant TTR and mouse serum amyloid P component. Amyloid fibril from transgenic mice was morphologically and immunohistochemically similar to that of human FAP. The most striking pathologic feature of the transgenic mice was the absence of amyloid deposition in the peripheral and autonomic nervous tissues. Thus, other intrinsic factors may be involved in amyloid deposition in the nervous tissues of human FAP.     

Expansion of trait of gibberellin-induced dormancy in the Tertiary relict species of the genus Dioscorea (Dioscoreaceae)

Effects of the application of gibberellin A₃ (GA₃) on sprouting of rhizomes and germination of seeds were tested in five species of the genus Dioscorea which are considered to be Tertiary relicts growing disjunctively in the Appalachians, the Balkans, and the Caucasus. Applied GA₃ at higher than 1 micro;M markedly inhibited sprouting of rhizomes of all species. However, inhibition of seed germination of these species by GA₃ application was not observed. It is hypothesized that before disjunction in the Tertiary period GA-induced dormancy probably prevailed in rhizomes of all members of the genus Dioscorea.     

Increase in IP3 and intracellular Ca2+ induced by phosphate depletion in LLC-PK 1 cells

The mechanisms by which Pi depletion rapidly regulates gene expression and cellular function have not been clarified. Here, we found a rapid increase in intracellular ionized calcium [Ca(2+)](i) by phosphate depletion in LLC-PK(1) cells using confocal microscopy with the green-fluorescence protein based calcium indicator "yellow cameleon 2.1." The increase of [Ca(2+)](i) was observed in the presence or absence of extracellular Ca(2+). At the same time, an approximately twofold increase in intracellular inositol 1,4,5-triphosphate (IP(3)) occurred in response to the acute Pi depletion in the medium. Furthermore, 2-aminoethoxydiphenyl borate completely blocked the [Ca(2+)](i) increase induced by Pi depletion. These results suggest that Pi depletion causes IP(3)-mediated release of Ca(2+) from intracellular Ca(2+) pools and rapidly increases [Ca(2+)](i) in LLC-PK(1) cells.     

The Effects of Various Ions on Resting and Spike Potentials of Barnacle Muscle Fibers

Effects of monovalent cations and some anions on the electrical properties of the barnacle muscle fiber membrane were studied when the intra- or extracellular concentrations of those ions were altered by longitudinal intra-cellular injection. The resting potential of the normal fiber decreases linearly with increase of logarithm of [K⁺]_out and the decrement for a tenfold increase in [K⁺]_out is 58 mv when the product, [K⁺]_out ·[Cl^-]_out, is kept constant. It also decreases with decreasing [K⁺]_in but is always less than expected theoretically. The deviation becomes larger as [K⁺]_in increases and the resting potential finally starts to decrease with increasing [K⁺]_in for [K⁺]_in > 250 mM. When the internal K⁺ concentration is decreased the overshoot of the spike potential increases and the time course of the spike potential becomes more prolonged. In substituting for the internal K⁺, Na⁺ and sucrose affect the resting and spike potentials similarly. Some organic cations (guanidine, choline, tris, and TMA) behave like sucrose while some other organic cations (TEA, TPA, and TBA) have a specific effect and prolong the spike potential if they are applied intracellularly or extracellularly. In all cases the active membrane potential increases linearly with the logarithm of [Ca⁺⁺]_out/[K⁺]_in and the increment is about 29 mv for tenfold increase in this ratio. The fiber membrane is permeable to Cl^- and other smaller anions (Br^- and I^-) but not to acetate^- and larger anions (citrate^-, sulfate^-, and methanesulfonate^-).     

Establishment and characterization of a bi-phenotypic leukemic cell line, NALM-19, from a patient with acute leukemia.

Based on the immunophenotypic and genotypic findings, this acute leukemia cell line, designated NALM-19, is unique in that a partial expression of both B-cell and myeloid cell features are present in this single clonal leukemic cell population. It is noteworthy that two "normal" EB virus-transformed B cell lines, B239 and B240, (paired with NALM-19) were established from the same leukemic blood.