At present, presumptive diagnosis of infiltrating brainstem lesions may be adequately undertaken with imaging methods, such as MRI. However, we believe that a stereotactically-guided biopsy provides an accurate method for diagnosing lesions of the brainstem. In our case, this procedure has been carried out entirely in the tomography room, without any complications of disease or mortality.

Motivated by the extensive clinical and experimental evidence that links the cerebellum to cognitive processes, we analyzed the auditory and visual memory of nine children with cerebellar tumors. Five patients had midline lesions and four had cerebellar hemispheric tumors. The patients were tested before and after surgery. One of the patients was also tested at 4 and 24 months after surgery. A third group constituted by four children, siblings of some of the patients, served as control. Statistically significant differences (P < 0.05) were found in the test of auditory memory, in which children with cerebellar tumors made a higher number of errors than their normal counterparts. Surgery performed according standard techniques did not increase significantly the number of errors in any of the tested categories. Location of the tumor (hemispheric vs midline) was not a determinant of the performance of the children. The patient tested up to 2 years after surgery demonstrated a progressive improvement in the performance of visual and auditory memory tasks. Our results provide further evidence that the cerebellum plays a role in the integration of auditory stimuli.

Sixteen patients were identified. Mean age of presentation was 8.8. An increased frequency of complications was observed in younger patients and longer survival rates in patients with greater resections; main mode of presentation was directly related to intracranial hypertension; size of tumor was not related to evolution or outcome. Modern histological classifications especially designed for children are deemed necessary to accurately diagnose GBM.

Studies were carried out on the male meiosis of Ellobius lutescens. The testicles of 29 male specimens were used for this purpose. Among 100 pachytene figures, 25 revealed an association between the sex vesicle and an autosomal bivalent of medium size, whereas in 75 figures the sex vesicle appeared as an isolated structure. The importance of this finding in relation to the proposed translocation of a segment of the Y chromosome to an autosome as well as the significance of this event in relation to a mechanism of sex determination in E. lutescens without zygote lethality is discussed.

Autoradiographic studies were done of DNA replication in the unpaired chromosome No. 9 of Eilobius lutescens. The replication sequence is identical in both sexes. The unpaired chromosome comprises approximately 5 % of the haploid complement, corresponding to the original-type X chromosome in the majority of placental mammals. The relation of the odd chromosome to the sex-determining mechanism of this species is discussed.

No abstract

The precise and diligent evaluation of a lesion caused by an animal bite may prevent further life-endangering complications. To the best of our knowledge, there are no reports about cerebellar abscess caused by a dog bite. When cranial lesions are penetrating, an abscess must to be considered. We insist on the importance of medical evaluation and adequate treatment of such lesions.

. This text encompasses a very correct and complete neuroanatomy of an eminently Galenic type.