A simplified aluminum stain in paraffin sections of bone from hemodialysis patients

A new simplified method has been devised for staining aluminum and has been tested in paraffin sections of bone from 60 patients who have undergone hemodialysis. Iliac crest bone fragments were fixed in 20% phosphate-buffered formalin for less than a day and demineralized at room temperature in 10% phosphate-buffered formalin containing 5% formic acid for only 2 to 3 hr. Four-micron paraffin sections, accompanied by positive controls, were stained with Maloney's aluminum stain, the Berlin blue reaction for iron, dylon or Congo red for amyloid and von Kossa's reaction for calcium. Aluminum and iron were demonstrated particularly at the mineralizing front of bony tissues; aluminum in 52 cases, iron in 45. Dylon staining also gave positive results in 52 cases. It is important in determining whether aluminum deposition is present that the von Kossa reaction remains positive even after demineralization. This method may be more useful for demonstrating aluminum in bony tissues than the complicated and time-consuming resin-embedding method currently used.     

Pharmacological profile of AA-861, A 5-lipoxygenase inhibitor

AA-861, a selective 5-lipoxygenase inhibitor, suppressed A23187-induced formations of 5-HETE and LTB₄ in rat peritoneal macrophages. Immunologically-stimulated generation of SRS-A was also inhibited in guinea pig lung and rat peritoneal cavity. AA-861 had no effects on histamine release from rat mast cels or passive cutaneous anaphylaxis in rats. Essentially no antagonistic activity to LDT₄ or histamine was observed. This compound exerted an obvious inhibition of allergic bronchoconstriction in guinea pigs and a moderate reduction of carrageenin-induced paw edema and pleurisy in rats. These findins suggest that SRS-A plays an important role in asthmatic and inflammatory reactions.     

Semiflexibility of collagens in solution

The persistence length of lugworm cuticle collagen in 0.1M acetic acid was evaluated as 1600 ～ 1800 Å by Yamakawa-Fujii's model for a wormlike chain from the sedimentation constant and the intrinsic viscosity. The persistence length was further examined for a series of sample “collagen sonicates” produced by varying the duration of sonic irradiation. To estimate the salt effect on the persistence length, measurements were made over a range of NaCl concentrations from 0 to 0.1M. The results showed that the cuticle collagen and collagen sonicates had identical values of persistence length and that the neutral salt effect for the cuticle collagen was far smaller than that for DNA.     

New Selective Growth Inhibitors of Sphaerotilus natans, Anslimins A and B

Selective growth inhibitors of Sphaerotilus natans were detected in the culture broths of several strains of Streptomyces. Anslimins A and B were isolated from the culture broth of Streptomyces oganonensis by adsorption on resinous adsorbent followed by elution with 50% aqueous acetone. The A and B components were then separated by cellulose powder chromatography. Physicochemical parameters of anslimins A and B revealed that these compounds are new peptide-containing structures. Anslimins A and B inhibited growth of S. natans at 0.78 and 0.39 μg/ml, respectively, but showed no activity against any of the other test microorganisms at 100 to 200 mg/ml. The anslimins had no harmful effect on guppies at a concentration of 100 mg/liter.     

Effects of prostaglandin A2 on Na+, K+-ATPase activity in basolateral plasma membrane of rat intestine in vitro

Prostagladin A₂, which prevents intestinal ulcers produced by administration of nonsteroidal antiinflammatory compounds such as indomethacin, inhibited the Na⁺,K⁺-ATPase activity in basolateral plasma membrane of rat intestine significantly. Prostaglandin A₂ inhibited mainly the Na⁺-dependent phosphorylation step in the overall reaction of Na⁺,K⁺-ATPase. This decrease of the Na⁺,K⁺-ATPase activity by prostaglandin A₂ was due to the decrease of Vmax of the enzyme and of the affinity of the enzyme for Na⁺. It was also suggested that the presence of both Δ^5,6 and Δ^10,11 structure of prostaglandin A₂ may be necessary for the inhibition of the Na⁺,K⁺-ATPase activity.     

Recruitment of T lymphocytes and induction of tumor necrosis factor in thyroid cancer by a local immunotherapy

Summary To elucidate the mechanism of action for intratumoral injection of immunopotentiators, infiltrating mononuclear cells and tumor necrosis factor (TNF) were assayed by immunostaining tissue samples of differentiated thyroid cancer resected with or without presurgical local application of OK-432, a streptococcal preparation. Frozen sections of resected specimens were stained with monoclonal antibodies using either a conventional or a modified immunoperoxidase method. The tumors injected with OK-432 showed increased T lymphocyte infiltration and HLA-DR expression on cancer cells as compared to the non-injected controls. Among these T cells, the CD4⁺ subset was more numerous than the CD8⁺ population. In four out of the seven cases constituting the injected group, numerous TNF-positive cells were seen in clusters or lines as well as scattered, while none of the seven cases in the control group was associated with a considerable amount of these cells. In their morphology and distribution pattern, these TNF-positive cells appeared to be of macrophage lineage. Thus local injection of OK-432 in thyroid cancer was shown to recruit T lymphocytes of predominantly the CD4⁺ subset and to induce in situ production of TNF, a known potent tumoricidal cytokine. The present data warrant further studies in this direction besides wider clinical intratumoral application of the reagent.     

Studies on structural proteins of the rat liver ribosomes. I. Molecular wights of the proteins of large and small subunits.

Structural proteins of active 60-S and 40-S subunits of rat liver ribosomes were analysed by two-dimensional polyacrylamide gel electrophoresis. 35 and 29 spots were shown on two-dimensional gel electrophoresis of proteins from large and small subunits, respectively. It was noted that the migration distances of stained proteins with Amido black 10B remained unchanged in the following sodium dodecyl sulfate-acrylamide gel electrophoresis, although some minor degradation and/or aggregation products were observed in the case of several ribosomal proteins, especially of those with high molecular weights. This finding made it possible to measure the molecular weight of each ribosomal protein in the spot on two-dimensional gel electrophoresis by following sodium dodecyl sulfate-acrylamide gel electrophoresis. The molecular weights of the protein components of two liver ribosomal subunits were determined by this 'three-dimensional' polyacrylamide gel electrophoresis. The molecular weights of proteins of 40-S subunits ranged from 10 000 to 38 000 and the number average molecular weight was 23 000. The molecular weights of proteins of 60-S subunits ranged from 10 000 to 60 000 and the number average molecular weight was 23 900.     

Annular nucleolus in Leydig cells of mouse

Summary Parathyroid glands of winter frogs (Rana pipiens) were compared by light and electron microscopy with those of winter frogs homoimplanted with pituitary glands. Serum calcium levels of untreated and pituitary-implanted animals were compared also. Forty-eight hours after pituitary implantation, serum calcium is elevated from a mean winter value of 6.2 mg % to 9.3 mg % and, morphologically, the parathyroid gland appears to be stimulated with respect to secretory activity. Compared with parathyroids of untreated winter frogs, intercellular spaces are diminished after pituitary implantation and glandular parenchyma is composed of cells with closely apposed plasma membranes thrown into interdigitating folds. Dense core vesicles are present in the cytoplasm and, together with microtubules, are encountered near plasma membranes. Golgi lamellae contain electron dense material and exhibit budding of dense core vesicles. Neither myelinated multivesicular bodies, presumably cytolysosomes degrading unneeded parathormone and organelles, nor focal dilatations with myelination of Golgi lamellae are encountered in parathyroid cells of pituitary implanted frogs. Rough endoplasmic reticulum and mitochondria do not undergo marked changes in distribution or abundance after pituitary implantation, indicating that the synthetic aspects of the secretory process are little altered in untreated and treated animals. It is suggested that in addition to Ca⁺⁺ a pituitary factor is involved in the seasonal changes in amphibian parathyroid structure and function.The authors wishes to thank Mrs. Mary Lee, Mr. Johnny Sandifer and Mr. M. G. Barker for expert technical assistance. This work was supported by the 1972 South Carolina State Appropriation for Research.     

Lysis of halophilic Vibrio alginolyticus and Vibrio costicolus induced by chaotropic anions

High concentration (1.0 M) of KSCN, but not of NaSCN, induced lysis of slightly halophilic Vibrio alginolyticus and moderately halophilic Vibrio costicolus, and the decrease in absorbance of the cell suspension was complete after 30 min at 25°C. Replacement of K⁺ with Na⁺ effectively prevented the lysis by SCN⁻. K⁺ salts of NO₃⁻, Br⁻, however, induced no significant lysis. In electron micrographs, a prolonged exposure of the cells of V. alginolyticus to 1.0 M KSCN displaced the nucleoplasm to maintain close contact with the cell membranes. After 40 min of interaction, 50% of the cellular protein, 96% of RNA and 94% of DNA were recovered in the lysed cells. In contrast to lysis in hypotonic conditions, the lysis induced by KSCN is due mainly to a partial release of protein from the cells. V. costicolus was more susceptible to SCN⁻ than V. alginolyticus, whereas nonhalophilic Escherichia coli was resistant to 1.0 M KSCN. Thus, lysis by SCN⁻ is characteristic of halophilic bacteria and cell membranes of more halophilic bacteria are more susceptible to chaotropic anions. The protective effect of Na⁺ observed here was considered to be manifested by specific interactions of Na⁺ with components of cell membranes, thereby rendering their structures resistant to the action of chaotropic anions.