Adsorption of mutagens to cotton bearing covalently bound trisulfo-copper-phthalocyanine

A method for separating nonpolar mutagens from their dilute aqueous solutions is described. It utilizes the affinity of the mutagens to a phthalocyanine derivative attached to cotton through a covalent bond. For mutagens having 3 or more fused aromatic rings in their structures, efficient adsorption took place on soaking the cotton in their solutions. The mutagens adsorbed can be recovered by elution with ammoniacal methanol. Mutagenicity in smoker's urine, cooked beef, and river water was detected by use of this method.     

A stable mitomycin-induced LC-type albino mutant of Blastocladiella emersonii

In an effort to obtain orange mutants ofBlastocladiella emersonii Cantino &Hyatt, wild type zoospores were treated with mitomycin. From the variants produced, we obtained a stable, albino mutant (Ma-1) that differs significantly from another, previously described (Shaw &Cantino, 1969) UV-induced, albino variant. This report concerns the origin of Ma-1, its distinguishing features, and its apparent similarity to the few LC (late colorless) plants that normally appear in wild type populations. A preliminary note regarding mitomycin-induced variants ofB. emersonii has been published (Matsumae &Cantino, 1970).     

Establishment and characterization of human neuroblastoma cell line (HSNB)

We cultured an aspiration fluid of the sternal bone marrow of the patient having adrenal neuroblastoma and established a neuroblastoma cell line (HSNB). The HSNB line has the following biological properties. 1. They are small round in shape and proliferate in flotation while forming cell aggregate, and often they attach the bottom of plastic dish and process the nerve-like fibers. A rough-endoplasmic reticulum are poorly developed, however, a lot of free ribosomes are scattered in the cytoplasm. In the peripheral area of the cells, small spherical secretory granules (60-140 nm in diameter) are existed. One characteristic of this cell is existence of microtubules in the cell-projections. 2. They show a stable growth and the doubling time is about 50 hours. 3. Their chromosome number varied widely and the mode is 46. The double minute chromosomes were present in 50% of cells. 4. When they are transplanted in the cheek pouch of hamster, they produced the neuroblastoma. 5. They produce neuron specific enolase. 6. N-myc gene was amplified ca 250 folds.     

Location in Muscarinic Acetylcholine Receptors of Sites for [3H]Propylbenzilcholine Mustard Binding and for Phosphorylation with Protein Kinase C

Muscarinic acetylcholine receptors purified from porcine cerebra or atria were covalently labeled with [3H]propylbenzilylcholine mustard ([3H]PrBCM), and then the labeled receptors were subjected to limited hydrolysis with trypsin, V8 protease, and lysyl endopeptidase, followed by analysis involving sodium dodecyl sulfate-polyacrylamide gel electrophoresis, fluorography, autoradiography, or immunostaining. The labeled peptides were located on the basis of their reactivity with antibodies raised against three synthetic peptides with partial sequences of the m1 or m2 receptor, and of their sensitivity to endoglycosidase F, which was taken as evidence that they contain glycosylation sites near the N terminus. The [3H]PrBCM-binding site in both cerebral and atrial receptors was found to be located between the N terminus and the second intracellular loop, because the size of the smallest deglycosylated peptide that contained both the [3H]PrBCM-binding and glycosylation sites was approximately 16 kDa. Cerebral receptors were 32P-phosphorylated with protein kinase C, and the major phosphorylation sites in cerebral muscarinic receptors were found to be located in a C-terminal segment including a part of the third intracellular loop, because a 32P-labeled peptide of 12-14 kDa reacted with anti-(m1 C-terminal peptide) antiserum. The presence of an intramolecular disulfide bond, probably between Cys 98 and Cys 178 in the first and second extracellular loops, respectively, was suggested by the finding that a peptide of approximately 17 kDa containing the [3H]PrBCM-binding site, but not the glycosylation sites, was partly converted to a peptide of approximately 12 kDa on treatment with beta-mercaptoethanol.     

Immunohistochemical distribution of basic fibroblast growth factor in experimental retinal ischaemia and reperfusion in the rat

Summary It has been proposed that basic fibroblast growth factor (basic FGF) mediates the neovascular response in a variety of conditions, including diabetic retinopathy and branch retinal vein occlusion. To test the hypothesis that basic FGF was released from retinal stores as a result of retinal ischaemia, transient retinal ischaemia was induced, followed by 48 h of reperfusion, in the rat by combined central retinal vasculature and optic nerve ligation. The immunolocalization of basic FGF was studied in the retina. We found that basic FGF in the normal retina is present around the deeper retinal vessels and in the neuronal tissue of the outer plexiform layer. In the eyes that had ischaemia followed by reperfusion, there was moderate cellular oedema with retinal swelling, and mitoses in the inner nuclear and plexiform layers. There were no changes evident at the immunohistochemical level either in the intensity or distribution of stores of basic FGF. We conclude from these data that stores of basic FGF are not altered dramatically under the conditions of transient experimental ischaemia and reperfusion in the rat, despite the presence of cellular proliferation.     

Conformational changes of α-lactalbumin induced by the stepwise reduction of its disulfide bridges: The effect of the disulfide bridges on the structural stability of the protein in sodium dodecyl sulfate solution

Four disulfide bridges of bovineα-lactalbumin (α-lact) were selectively reduced to obtain its derivatives with three, two, and zero disulfide bridges (designated as 3SS, 2SS, and OSSα-lact, respectively). The original helicity was almost maintained in 3SSα-lact missing only the Cys6-Cysl20 bridge. Upon the reduction of both Cys28-Cys111 and Cys6-Cys120 bridges, various changes occurred in the protein. In particular, the maximum fluorescence of 1-anilinonaphthalene-8-sulfonic acid was observed in this stage. Upon the reduction of all disulfide bridges, the hydrophobic box of the protein, formed by Trp60, Ile95, Tyr103, and Trp104, was disrupted and an internal helical structure was destroyed. The conformation of each derivative was examined mainly in a solution of sodium dodecyl sulfate. In the surfactant solution, the helicity increased from 33% to 37% in 3SSα-lact, from 26% to 31% in 2SSα-lact, and from 18% to 37% in OSSα-lact, as against from 34% to 44% in intactα-lact. On the other hand, the tryptophan fluorescence of each derivative was affected in very low surfactant concentrations, suggesting that the tertiary structure considerably changed prior to the secondary structural change in the surfactant solution.