Juan J. Angulo

Demonstration of viral inclusion bodies in unstained tissue sections with the aid of the phase microscope

With the aid of the phase microscope, the inclusion bodies of rabies, vaccinia, wheat mosaic, yellow bean mosaic, ectromelia, meningopneumonitis, feline pneumonitis, mouse pneuimonitis, and feline panleukopenia were easily examined in unstained tissue sections. Besides, the inclusion body of trachoma was studied in smeans. Possible applications of the phase microscope in Virology are proposed.

Electron Microscopy Study of Chick Embryo Erythrocytes

Summary Electron micrographs of os-mosis-hemolyzed erythrocytes from healthy chick embryos are presented. The cells are examined unfixed, unstained; formalin-fixed., unstained; formalin-fixed, hematoxylin stained; formalin-fixed, safranin stained; formalin-fixed, methyl green stained; osmic acid fixed unstained; and silver nitrate-fixed, unstained. Unfixed, unstained erythrocytes prepared by the technic employed showed a transparent cytoplasm so that the direct visualization of intracytoplasmic parasites might be possible by this procedure. Some nuclear structure was observed, and there is evidence for the existence of a cell membrane. Fixed erythrocytes clearly showed an envelope. Fixation and drying produced specimen changes, and in the specimens examined the processes of electron microscopy provoked les radical changes than did the fixation.

Some Anatomical Characteristics of the Hutia Conga

interpreted with reference to the locomotor behavior patterns of the group. In these basic forms studied, the tendencies that are carried to extreme in the ruminants and the horses are seen in the beginning stages. The reduction of the number of toes and the lengthening of the metapodial segments are the notable processes. Limitation of the use of the hind foot to support of the body has operated to simplify the muscular system. The loss of the fleshy nature of the flexor digitorum pedis illustrates the point. It is remarkable, however, that the flexores profundi remain in such a primitive condition. Only in the peccary was the fleshy nature of certain of the members lost. While reduction in the number of digits usually means the dropping of all parts associated with the missing members, the surprising conservatism of the muscular system is seen in the disposition of the contrahens of the 5th toe. This has become a vestigial structure and has shifted its insertion to the 4th toe.

Electron Microscopic Observations of Stromatolysis in Human Erythrocytes.

Summary Widely different degrees of stromatolysis were observed electron microscopically in erythrocytes which occurred in preparations of Treponema carateum taken from tissue fluid of skin lesions. A comparison of electron images with light microscopic images of cells under controlled conditions of stromatolysis showed striking similarities. Isolated appearances in the electron micrographs similar to all the stages of disintegration of hemolyzed erythrocytes reported by Furchgott from light microscopy are represented and observed.

Data on the Mouse Spinning Test.

The mouse spinning t e s t 1 which consists of holding a mouse b y the tail , twir l ing the l a t t e r a t a fas t r a te for severa l seconds and subsequen t ly leaving the an imal on a hor izonta l surface to observe i ts behav io r was sy s t ema t i ca l l y used th roughou t a t t e m p t s to isola te an infectious agen t from pemphigus foliaceus cases. This was done for the ea r ly de tec t ion of the signs which might be p roduced b y the inocula ted mater ia l . Since an exper imentM infection could not be obta ined , the spinning t e s t disclosed signs of nervous sys tem invo lvement in inocula ted bu t hea l thylook ing animals . These signs and the i r incidence ra tes were then s tud ied in the un inocu la ted control animals . The resul ts of the spinning t e s t in nninocula ted mice are r epor t ed here. The mice employed came from the colonies of the following ins t i tu t ions , all loca ted wi thin the l imits of the c i ty of S~o Paulo or in i ts immed ia t e v ic in i ty : B u t a n t a n Ins t i tu t e , Adolfo Lutz Ins t i tu t e , Pemphigus Fol iacens Service, Biologic Ins t i tu te , and Pinheiros Ins t i tu t e . The pa ren t s tock of all these mice was the Swiss s t ra in mice b rought to Brazi l by the In te r nat ionM H e a l t h Divis ion of the Rockefel ler Founda t ion . I so la t ion of mouse encephalomyel i t i s (Theilers disease) virus, l ymphocy t i c chor iomeningi t is and p leuropneumonia l ike organisms from such a s tock has been r epor t ed 2-~.