Robert C. Rubin

Reconstitution of the cerebral cortical mantle in shunt-corrected hydrocephalus.

The purpose of this study was to ascertain the sequence of events and the cellular constituents involved in reconstituting the cortical mantle after ventricular shunting. The subjects were severely hydrocephalic adult cats. After insertion of a shunt, the ventricular system rapidly returned to normal size and there was gross reconstitution of the cortical mantle. However, there still remained in the cortical mantle many of the histological changes seen before insertion of the shunt. The effect of hydrocephalus is mainly upon axons in the periventricular white matter. The axons become stretched and finally disrupted, resulting in disintegration of the surrounding myelin. In the absence of axons, remyelination cannot take place. It would seem, therefore, that prompt reversal of hydrocephalus is necessary in order to preserve the anatomical and functional integrity of the brain.

The Effect of Severe Hydrocephalus on Size and Number of Brain Cells

Histological and biochemical studies were made of the brains of 13 hydrocephalic adult cats and 7 control animals in order to establish whether there is any significant variation in the size or number of brain cells as a result of hydrocephalus and whether such variation could be a factor limiting repair of cerebral damage.

Disc Space Infections in Children

Intractable low back pain in children is often due to disc space infections. The clinical presentation, diagnostic workup, and treatment of four cases are presented. Symptoms often occur well before radiographic findings are evident. The diagnosis can only be made by a high degree of suspicion and repeated X-rays. Antecedent causes, such as urinary infection or intravenous administration of narcotics were lacking in this group. Fever or a preceding febrile illness was often, but not invariably, present. Percutaneous biopsies were not usually helpful. Myelography in each instance was normal. Bed rest reduced but did not alleviate the back pain. The institution of appropriate antibiotic therapy resulted in a prompt diminution of pain.

Reconstitution of Cerebral Cortical Mantle following Hydrocephalus

The reconstitution of the cerebral cortical mantle is, at present, a radiographic myth. Although there is indeed a thickening or reconstitution of the cerebral mantle following treatment for hydrocephalus, it may be more apparent than real. To understand the changes provided by the reversal of hydrocephalus, it is necessary to define the effect of ventricular dilatation on the surrounding brain. It is also essential to update classic neuropathological and neuroanatomical studies29 with observations obtained with both electron microscopy and quantitative biochemical analysis.

Anatomy of the Brain and Skull

Title Type anatomy of the brain and skull PDF anatomy of the brain and skull necklace PDF anatomy of the brain and skull model PDF anatomy of the brain and skull diagram PDF anatomy of the brain and skull layers PDF anatomy of the brain and skull anatomy PDF anatomy of the neck and skull anatomy PDF anatomy quiz on skull PDF anatomy of the neck and skull PDF anatomy of the neck and skull muscles PDF anatomy of the neck and skull numbness PDF anatomy quiz skull bones PDF anatomy of the neck and skull arthritis PDF anatomy quiz on skull bones PDF anatomy skull bones quiz PDF anatomy coloring page of skull PDF anatomy human skull worksheet PDF anatomy human skull illustration PDF anatomy human skull diagrams PDF anatomy of the neck and skull pain PDF anatomy coloring pages of the skull PDF anatomy human skull parts PDF download anatomy of skull by bd chaurasia pdf file PDF anatomy and physiology coloring workbook answers skull PDF anatomy of the brain PDF anatomy of the brain poster PDF anatomy of the brain stem PDF anatomy of the brain quizzes PDF anatomy of the brain simplified PDF anatomy of the brain quizlet PDF anatomy of the brain quiz PDF anatomy of the brain songs PDF anatomy of the brain lecture PDF anatomy of the brain and functions PDF anatomy of the brain psychology PDF anatomy of the brain pictures PDF anatomy of the brain song PDF anatomy of the brain and its function PDF anatomy of the brain youtube PDF anatomy of the brain diagram PDF

CURRENT PROBLEMS IN THE MANAGEMENT OF MALIGNANT BRAIN TUMORS

The prognosis for patients with malignant brain tumors remains poor. Serendipity and chance may lead to a cure, but in the meantime a rational approach is demanded, one that must involve a fundamental understanding of the nature of the malignant process. The glial tumors induced with chemical carcinogens’,? in the early 1940’s have become standard laboratory models. Of importance in the life history of these tumors is the finding that the site of carcinogen implantation determines the type of glioma that is produced. This suggests that the malignant process arises not in a single totipotential cell or embryonic rest, but diffusely in any cell that can be influenced chemically or virally. It has been suggested that there may be two modes of action in carcinogene~is.~ The first is an irreversible change called initiation, which does not cause cancer but which does modify the cell in an undefined manner. The second is a reparable change called promotion, which, in itself, causes only a low incidence of tumors, but which, following the initiating compound, even after a considerable delay, causes a high incidence of cancer. It is becoming increasingly evident that a wide variety of chemical agents are effective carcinogens. The production of tumors with nitrosamine has been de~ c r i b e d . ~ A most significant finding is the ability to produce central nervous system tumors in the offspring of pregnant animals who have been subjected to a single dose of carcinogen. The production of tumors in animals by exposure to a carcinogen at a critical time may find a parallel in the late development of human neoplasms resulting from radiation exposure. Perhaps this represents the inducing insult that, under favorable conditions, will subsequently give rise to cancer. The animal models, however, have not given us specific insight into the variations of the natural histories of central nervous system gliomas. Particularly unexplained are the different biological activities of childhood gliogenous tumors, such as the cystic cerebellar astrocytoma, when compared with their adult counterpart. Evidence is accumulating from research with hepatomas that slowly growing benign tumors have less enzyme deletions and a more normal chromosome pattern than do rapidly growing tumors. Perhaps the immunological or hormonal environment of the young animal is more favorable to the establishment of “minimal deletion” tumor^.^ The significance of virus particles in tumors is not a new problem. In 1944, it was stated that “the only serious objection to be brought against the viral hypothesis is that it remains ~nproved .”~ This problem has been pursued by investigating the Zimmerman ependymoblastoma. This tumor is being studied intensely throughout the country, and it illustrates some of the problems that can be encountered in the study of experimental tumor systems. The Zimmerman ependymoblastoma has been maintained by transplantation for 20 years, and many subsequent lines have been derived from this primary source.6 These cuboidal tumor cells have a tendency to form cords lining the