A case of the cerebellar form of progressive multifocal leukoencephalopathy (PML) without remarkable immune depression or immune deficiency is reported here. The patient was a 74-year-old-woman who had complications of chronic renal failure and renal anemia for several years. Seven months before her death she had symptoms of general fatigue, gait disturbance and articulation disorder. During her hospitalization period her neurological disorder gradually progressed irreversibly with failure of consciousness and she died of respiratory failure. She did not have remarkable clinical signs of immunodeficiency nor did she receive immunosuppressive therapy. Clinically she had not been diagnosed with PML. At the post-mortem examination different degrees of demyelination were observed in the brain white matter: diffuse and severe in the cerebellum, moderate and coalescent in the brainstem, and light and patchy in the cerebrum. JC virus antigen-positive cells were frequently observed in the demyelinated lesions in the cerebrum and sometimes observed in the brainstem, but were rarely found in the cerebellum. These findings suggest that PML lesions may be present with different degrees of demyelination that are inversely correlated with the number of JC virus-infected cells. This fact should be considered when evaluating the brain biopsies of PML patients.

Heart rate variability (HRV) was studied in 19 patients with severe obstructive sleep apnea syndrome (OSAS), 17 with mild OSAS and 19 control subjects. A very low frequency (VLF) component during sleep in frequency-domain analysis was significantly higher in patients with severe OSAS, but not in patients with mild OSAS, compared with controls. It suggests that VLF is useful for the screening of severe OSAS, but not for mild OSAS. In addition, a low frequency (LF) component during sleep was also elevated in patients with severe OSAS. Further investigation is needed to understand the underlying causes of the LF elevation.

Risperidone (RIS) is a novel antipsychotic agent whose pharmacokinetics have yet to be fully determined. In particular, little is known about RIS following an overdose. We report the pharmacokinetics following ingestion of a high dose of RIS by serially measuring the plasma concentration in two patients. These patients were admitted in a comatose state following an intentional overdose of RIS; all patients survived. In the first patient, 14 mg of RIS had been ingested 2 hr before the first blood sample was obtained. The second patient ingested an estimated 90 mg of RIS. Seven time-points were determined. The maximum concentration of unaltered RIS was 325 ng/mL and that of the principal metabolite (9-hydroxy-risperidone: 9-OH RIS) was 139 ng/mL. By plotting the time-concentration curve for the active fraction (RIS plus 9-OH-RIS) in the first and second patients, the half-life of RIS following overdose was determined and was approximately 12.7 hr and 17.8 hr, respectively. These values are similar to the half-life of RIS in healthy individuals ingesting a therapeutic dose. Two patients did not developed parkinsonism nor dystonia, and were discharged without sequelae.

We encountered an autopsy case of renal failure complicated by cerebral tuberculosis. The patient was hospitalized due to disturbance of consciousness, and dialysis therapy was performed because of end-stage renal failure. Approximately 1 week later, abnormal shadows were observed on chest X-ray, and various examinations were performed until the diagnosis was finally determined as miliary tuberculosis. Disturbance of consciousness was exacerbated, despite the administration of antituberculosis drugs and other treatments, and the patient died on the 105th hospital day. Pathological examinations demonstrated miliary tuberculosis associated with intracranial involvement, in addition to contracted kidneys. In patients with end-stage renal failure, the risk of developing tuberculosis, miliary tuberculosis in particular, is reported to be much higher than in normal subjects. However, the diagnosis of miliary tuberculosis is difficult to establish, because of nonspecific symptoms and the low rate of detection of acid-fast bacteria from the sputum. Comprehensive understanding of the results of frequent culture examinations of sputum and blood, contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI), and Polymerase chain reaction (PCR) of cerebrospinal fluid, as well as albumin concentration in the cerebrospinal fluid, are considered useful in diagnosing intracranial tuberculosis. Although cerebral tuberculoma is rare, prolonged disturbance of consciousness may be related to cerebral tuberculosis. Therefore, particular attention should be paid to patients with end-stage renal failure complicated by disturbance of consciousness.

Abstract-Propranolol produces a sustained rise in blood pressure in the rat, but little change in the guinea pig. In order to elucidate this distinct difference, the fol lowing experiments were carried out: (a) The pressor effect of propranolol was studied while the vascular tone was changed by infusion of several vasoactive substances in the guinea pig; (b) The effect of propranolol on the isolated atria of rats and guinea pigs was also compared. Propranolol always produced a pressor action during the infusion of adrenergic β-stimulating agents, but not during vasopressin infusion. In spontaneously beating or electrically driven guinea pig atria, propranolol reduced the contractile force to a greater extent than in rat atria. It is concluded that the dif ference in action of propranolol on the blood pressure of rat and guinea pig may be explained by the following two reasons: (a) the β-adrenoceptive vasodilator tone in skeletal muscle is stronger in the rat than in the guinea pig; (b) the heart of the rat is less sensitive to propranolol than that of the guinea pig.Many investigators (1-5) reported that propranolol produced a fall in blood pressure in various species of experimental animals. Hypotensive effects of propranolol have been also reported in patients after prolonged oral administration (6-8). Meanwhile we re ported in previous papers (9, 10) that propranolol produced a sustained pressor action in the rat. This action may be due to the blockade of the ~-adrenoceptive response of peripheral vascular smooth muscle which dominates the maintenance of normotension in the rat.Such diverse pressor action of propranolol in the rat may be explained as follows:(a) The j-adrenoceptive vasodilator activity maintains the tone in blood vessels of skeletal muscle mediated through the central nervous system more effectively in the rat than in the other species of animals, or (b) the heart of the rat is less sensitive to propranolol than that of other species.In this experiment, guinea pigs were compared with rats as to the pressor effects of propranolol when the vascular tone was changed by the infusions of various vasoactive substances. The effects of propranolol in the isolated atria of rats and guinea pigs were also compared. MATERIALS AND METHODS I. Experiments in guinea pigsGuinea pigs of both sexes, weighing between 350 and 450g were anesthetized with urethane (1.5 g/kg s.c.). Arterial blood pressure was measured at the right carotid artery