Surreptitious superwarfarin ingestion with brodifacoum.

Physicians must have a high index of suspicion when patients have unexplained prolongation of the prothrombin time and bleeding in the absence of detectable warfarin. Several common rodenticides contain modified versions of warfarin that are not detectable in standard warfarin assays. We present a case of surreptitious brodifacoum ingestion in a patient who had years of unexplained bleeding and negative warfarin levels.

Fatal rabies associated with extensive demyelination.

OBJECTIVE: To compare the clinical course with the neuropathological findings in a patient who died of acute rabies encephalomyelitis with coexisting demyelinating lesions. DESIGN: Patient's history was extensively investigated, during her illness and after death. Details of her previous allergies, postexposure prophylaxis, early use of steroid therapy, 20-day course in an intensive care unit, and autopsy results are clinicopathologically correlated. SETTING: The intensive care unit of an 1100-bed tertiary referral center and teaching hospital. PATIENT: A 55-year-old woman, referred by her family doctor. CONCLUSIONS: Postvaccinal encephalomyelitis and rabies can run similar courses and can be misdiagnosed. On admission to the hospital, this patient was initially diagnosed as having postvaccinal disease. However, autopsy results and postmortem viral cultures disclosed a complex picture, including acute rabies and widespread perivenous demyelination. One other similar report from 1977 in the literature is reviewed. No adequate explanation of the rare coexistence of acute rabies encephalomyelitis and perivascular demyelination is available.

Gradient in the effects of ethyl alcohol on canine gastric antral circular muscles.

The effects of ethyl alcohol on the electrical and mechanical activities of canine gastric antral circular muscle were studied. Recently it has been reported that the circular layer of the antrum is not homogenous in its electrical activity. Therefore, circular muscles from the regions adjacent to the myenteric and submucosal borders of the circular layer were studied separately to compare the actions of ethyl alcohol through the thickness of the circular layer. In the first series of experiments concentration-response data were collected to describe the effects of ethyl alcohol on the contractile activities of myenteric and submucosal muscles. The data show that ethyl alcohol is more effective as an inhibitor of myenteric contractions than submucosal contractions. Next, experiments were performed to determine the electrical mechanism responsible for the contractile effects. Circular cells of submucosal and myenteric regions were impaled, and the muscles were exposed to several concentrations of ethyl alcohol ranging from 0.1 to 1.5%. Slow wave activity was reduced in frequency and amplitude in both regions. The inhibitory effect of ethyl alcohol on electrical activity was greater in submucosal muscles, but mechanical activity was less affected in these muscles because excitation-contraction coupling occurs at more polarized levels in the submucosal portion of the circular layer.

Effects of ethyl alcohol on phasic and tonic contractions of the proximal stomach.

The effects of ethyl alcohol (EtOH) on the contractile activities of canine gastric corpus and fundus circular muscles were studied. EtOH, 0.1 to 1%, inhibited phasic contractions of corpus muscles but enhanced tonic contractions. These effects were both concentration dependent. The same range of EtOH concentrations caused a transient rise followed by a fall in the level of tone of fundic muscles. The effects of EtOH on ACh-stimulated contractions were also studied. Phasic contractions were stimulated by ACh and inhibited by EtOH. EtOH augmented the tone responses of both corpus and fundus muscles to ACh. Experiments were also performed to test whether EtOH had specific and direct effects on these muscles. The effects of EtOH were apparently not mediated by prostaglandins or Ach and were not, at least in corpus muscles, a nonspecific result of the hyperosmolarity of EtOH solutions. The data supplement previous studies on muscles of the distal stomach where the effects of EtOH were inhibitory to phasic contractions. The finding that the proximal stomach responds to EtOH with tonic contraction may help explain some of the controversy in the literature about the effects of EtOH on gastric emptying.

Slowly alternating skew deviation: description of a pretectal syndrome in three patients.

Three patients who had slowly alternating skew deviation are described; each had elements of the Sylvian aqueduct syndrome. This combination of signs supports a pretectal location for lesions associated with alternating skew movements. Postmortem examination of a patient who died of chronic herpes simplex encephalitis showed extensive demyelination and periaqueductal spongiform degeneration; there was preservation of the oculomotor and trochlear nuclei, the medial longitudinal fasciculus, vestibular nuclei, and the interstitial nucleus of Cajal bilaterally. The slowly alternating dysconjugate vertical movements bear a resemblance to both see-saw nystagmus and the ocular tilt response.

Syringoencephalomyelia (syringocephalus).

This is the fourth recorded patient with extension of syringomyelia into the brain rostral to the mesencephalon verified at autopsy. A syrinx was demonstrated from the low thoracic segments of the spinal cord to the cervico-medullary junction, where a fibrovascular malformation and dural-arachnoid adhesions deformed the pyramids. Cavities in the spinal cord were continuous, with rostral glial-lined cavities in both corticospinal tracts through a system of sponge-like tubes. The rostral extent of these cavities on the right was the centrum semi-ovale above the neostriatum; on the left, the cavities extended to the diencephalon. A classical lateral-dorsal syringobulbia in the right medulla accompanied the syringoencephalomyelia (syringocephalus).

Delayed, relapsing experimental allergic encephalomyelitis in mice.

Immunization of female SJL mice with an emulsion of lyophilized mouse spinal cord, pertussis vaccine, and complete Freund's adjuvant produces a delayed and often relapsing form of experimental allergic encephalomyelitis (DR-EAE). The mice develop initial signs of disease an average of 6 mo after immunization. Relapses occurred 2 wk to 11 mo after the initial illness. Some animals had multiple relapses. Pathologic examination of the brain and spinal cord revealed perivascular infiltration of mononuclear cells with acute demyelination. Areas of subacute and chronic demyelination ("plaques") were also seen. This model produces a clinical course of relapsing-remitting disease with pathologic evidence of both recent and old inflammatory lesions at various levels of the central nervous system. It thus more closely resembles multiple sclerosis than acute EAE.

An overview of pituitary tumors.

Tumors arising in and around the hypophyseal fossa can cause symptoms by compression of surrounding structures or, in the case of adenomas arising from the adenohypophysis, by hypersecretion of hormones. Until recently, adenomas of the hypophysis have been classified on the basis of light microscopy into chromophobe, eosinophilic and basophilic. Presently available methods of histochemistry, immunocytology, electron microscopy and hormone assays make available a biological classification of these adenomas into two groups: (I) adenomas without secretory activity and (II) adenomas with secretory activity. Amongst the latter are included somatotroph adenomas, prolactin cell adenomas, melanocorticotroph adenomas and thyrotroph adenomas. Many of the large group of tumors formerly called "chromophobe" can now be reclassified amongst the secretory adenomas.

Meningioma of the paranasal sinuses.

Meningiomas originating in the paranasal sinuses are rare. These tumors are thought to arise from embryonal arachnoid nests which were pinched off and left behind during embryonic development. We have described various radiographic findings of two patients with meningioma arising in the paranasal sinuses (frontal sinus origin in a 65-year-old female, and sphenoid sinus origin in a 26-year-old female). The paranasal origin of meningioma was accurately determined on the basis of CT and arteriography. A review of the 11 cases previously reported and our cases indicates that there are no specific clinical or radiographic findings of meningiomas of the paranasal sinuses.

Trans-sphenoidal removal of a Rathke's cleft cyst.

Symptomatic Rathke's cleft cysts are uncommon. We present a case with suprasellar extension manifested by hypopituitarism and visual disturbances. The treatment was trans-sphenoidal evacuation and partial removal of the capsule. We suggest that the trans-sphenoidal approach to these lesions is usually adequate and that radical removal of the capsule is not necessary.

Chorioallantoic membrane heterotransplantation of human brain tumors.

Specimens of human tumors were taken from the operating room and directly heterotransplanted to chick chorioallantoic membranes. Seventy-one percent of the eggs survived the procedure and 41% of the tumors appeared viable after 1 week. Microscopically, the first-generation heterotransplants resembled the parent tumors. Many specimens showed evidence of growth, but in most of them there was also some degree of necrosis. The necrosis increased with serial heterotransplantation, so that tumor propagation usually was not possible beyond the second to third transplant generation; nevertheless, it was found that almost any histological type of intracranial tumor could be grown for short periods of time at least on the chick chorioallantoic membrane.