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Immune responsiveness of inbred mice to low doses of ovalbumin or ovomucoid is under control of single dominant genes closely linked to alleles of the H-2 locus. High responsiveness to ovomucoid is linked with the H-2a and H-2k alleles, and to ovalbumin with the H-2b, H-2d, and H-2q alleles.

Solutions of Parlodion stored in clear glass bottles, and subjected to the usual lighting of laboratory work tables, deteriorate progressively. Blocks of nervous tissue stained by Cajal's formula No. 6 underwent marked fading when embedded in old, light-affected Parlodion solutions. Storage of nitrocellulose, either as a solid or in solution, should be in darkness, in a dark colored bottle, for example.

Five methods of removing bound formalin from tissues were studied with the Cajal, Del Rio-Hortega, and Feulgen technics used as indicators of efficiency of removal. The tissues had been fixed in 10% formalin for varying periods from one week to several years. The most effective means of eliminating the effects of formalin on staining was two 24-hour changes of 20% aqueous chloral hydrate. Tissue so treated (in the block) gave good results with both the Feulgen and Cajal technics. The Del Rio-Hortega silver carbonate method did not differentiate microglia and oligodendroglia, although astrocytes, unstained in untreated material, stained well after deformalinizhig.

Natural α-recoil damage of 30 natural zircon specimens from Ceylon have been examined by studying the infrared absorption spectra from 1 to 15 μm. Two synthetic zircon specimens were also studied as undamaged reference specimens. The ir absorption coefficient at 6 μm (1666 cm-1) was found to be a function of radiation damage. The ir data can be explained by a dual damage mechanism. The initial damage process produces degradation of the v3 vibrational mode in the ir spectra which can be explained by deformation of SiO4 tetrahedra, whereas the predominant effect of the advanced stage of radiation damage is the breakdown of the zircon lattice into SiO2 and ZrO2 which causes a skewing of the v3 absorption band. These data substantiate the model of Pellas and clarify the dualistic nature of the radiation damage mechanism.

Beschreibung eines chronisch-progressiven Krankheitsbildes mit schubweisem Verlauf und Exitus nach einem Schub. Die Symptomatologie bot eine Mischung von pyramidalen und extrapyramidalen Störungen, die keinem der bisher bekannten Krankheitsbilder entspricht. Als besonderes Symptom wird eine nur bei passiven Bewegungen hervortretende Hypertonie hervorgehoben, die möglicherweise einen „Baustein“ der sonst beobachteten komplizierten extrapyramidalen Bewegungsstörungen darstellt. Hinweis auf das Vorkommen von Erweiterung des Cavum septi pellucidi bei verschiedenen mit Hydrocephalus interims verlaufenden Erkrankungen. Auf Grund der Literatur wird auf die Möglichkeit der ventrikulographischen und auf Grund eines eigenen Falles auf die Möglichkeit encephalographischer Darstellung dieses Cavums aufmerksam gemacht. Dies spricht entgegen der geltenden Meinung für eine Kommunikation des Cavum mit dem Ventrikelsystem, wobei weitere Untersuchungen ergeben müssen, ob es sich dabei immer um eine pathologisch bedingte Verbindung handelt.

1. The movement of fluorescein across the retinal surface of the rabbit's eye was estimated by measuring the concentration gradient of the dye in the vitreous body. These measurements were made in vivoby means of a slit‐lamp fluorophotometer, or were taken from frozen sections of enucleated eyes.

Although many endogenous substances are known which promote an increase in capillary permeability, controversy still exists as to the precise mechanism of their action,1-3 it having been variously suggested that the leakage occurs through the endothelial cells themselves, or through the intercellular cement, or through gaps resulting from a reversible separation of the endothelial cell margins. Nor is there agreement about the exact site within the vascular tree at which these permeability changes primarily occur.The recent work of Majno and Palade4 and of Majno, Palade, and Schoefl5 goes far to resolve these problems. By injecting histamine or serotonin into the cremaster muscle of rats, in which colloidal carbon or mercuric sulphide had previously been introduced into the circulation, they demonstrated, by both light and electron microscopy, the site and structural mechanism of the resulting changes in permeability.It was seen that the endothelial cells first partially

In 500 albino rats, the Wallerian degeneration of the lateral olfactory tract, after making a lesion in the olfactory bulb, was studied with the most important variations of Cajal's silver impregnation methods for blocks and with the Bielschowski-Gros method for sections. Cajal's variations were, in general, excellent for the study of the lesion and for the degeneration proximal to it, but were inaccurate for degeneration at a greater distance from the lesion (distal degeneration). For this distal degeneration and for thin collaterals, the Bielschowski-Gros method was better, and allows one to map consistently and accurately the distribution of the tract.

The nerve endings of the adrenal medulla of the rabbit were studied under the electron microscope in the normal condition and after prolonged electrical stimulation of the splanchnic nerve. With a stimulus of 100 pulses per second for 10 minutes, there is an increase in the number of synaptic vesicles in the nerve ending. The mean number is of 82.6 vesicles per square micron in the normal and of 132.7 per square micron in the stimulated glands. With a stimulus of 400 pulses per second for 10 minutes, there is a considerable depletion of synaptic vesicles and other changes occur in the nerve endings. The mean number of vesicles is of 29.2 per square micron. These results are interpreted as indicative of an increased activity of the ending in one case, and as a diminished activity and fatigue of the synaptic junction in the other.

Anaphylactic release of histamine was induced in mouse mast cells after sensitization with mouse, rat, or rabbit antibodies. As compared with homologous antibodies, rat antibodies were quite effective, whereas, rabbit antibodies were poorly effective. Guinea pig antibodies (γG1 and γG2) were ineffective. Pepsin-digested preparations of rabbit antibodies were unable to sensitize mouse mast cells, or mouse skin, for the PCA reaction.

Immunization of inbred strains of mice with repeated minute doses (0.1 to 1.0 microgram) of hapten-protein conjugates demonstrated wide differences in the magnitude of their antibody responses, which were related to the histocompatibility (H-2) type of the strains. Immunization with a single high dose (100 micrograms) of antigen failed to demonstrate these differences.

The inheritance of responsiveness to histamine-sensitizing factor of pertussis bacilli was examined in (SWR/J x CBA/J)F1x CBA/J backcross mice. We found that about half of the backcross mice inherited this responsiveness in both sexes. There was no linkage between the inheritance of responsiveness to histamine-sensitizing factor and the H-2qlocus from the sensitive SW/J progenitor.

Contrasting values of remnant thermoluminescence of limestone samples from Jaguar Cave, eastcentral Idaho, reveal temperature differences attributable to position within the cave microenvironment. Absence of recorded temperature change during cave-filling by rock and human debris indicates brevity of human occupation, which was near the end of Wisconsin (Pinedale) time.

IT has been reported previously1that the α-glycerolphosphate dehydrogenase (L-glycerol-3-phosphate: NAD+oxido-reductase, E.C. 1.1.1.8), either the crystalline form of the enzyme (Boehringer, U.S.) or that present in the post-mitochondrial fraction of rat liver and hepatomas, could be activated by potassium cyanide. At that time it was also found, although published only recently2, that potassium cyanide increased the anaerobic production of α-glycerolphosphate (GP) from glucose-6-phosphate by the fortified post-mitochondrial fraction of three rat hepatomas.