A 6-hydroxydopamine-induced selective parkinsonian rat model: further biochemical and behavioral characterization

The main focus of the present study was to define the rotational response of 6-hydroxydopamine-lesioned rats to dopaminergic agonists to separate the partially lesioned rats from those having complete substantia nigra (SN) and ventral tegmental area (VTA) lesions. Animals were challenged by amphetamine and L-DOPA for 10 consecutive weeks. There was a correlation between rotational behavior and extent of midbrain cell loss. Rats with complete SN and < 40% VTA lesion turned more than 5 times/min after amphetamine administration, but not after L-DOPA; animals with complete SN and 40-80% VTA lesions turned vigorously following amphetamine and began turning after L-DOPA administration. Rats with complete SN and VTA lesions turned less after amphetamine than the other two groups, while their turning after L-DOPA administration increased. Extracellular dopamine (DA) measured by microdialysis, intracellular DA measured by postmortem tissue punches, and tyrosine hydroxylase-immunoreactive cell count in SN and VTA were also evaluated. It appears that the dopaminergic cells in the lateral VTA affect DA concentration in the medial caudate nucleus. In the nucleus accumbens of the lesioned side, DA release and metabolism substantially increased with the larger VTA lesion. Dopamine turnover rate in the caudate was also higher in the group with < 40% VTA lesion.

Application of a physiologically based pharmacokinetic model informed by a top-down approach for the prediction of pharmacokinetics in chronic kidney disease patients

Quantitative prediction of the impact of chronic kidney disease (CKD) on drug disposition has become important for the optimal design of clinical studies in patients. In this study, clinical data of 151 compounds under CKD conditions were extensively surveyed, and alterations in pharmacokinetic parameters were evaluated. In CKD patients, the unbound hepatic intrinsic clearance decreased to a similar extent for drugs eliminated via hepatic metabolism by cytochrome P450, UDP-glucuronosyltransferase, and other mechanisms. Renal clearance showed a similar decrease to glomerular filtration rate, irrespective of the contribution of tubular secretion. The scaling factor (SF) obtained from the interquartile range of the relative change in each parameter was applied to the well-stirred model to predict clearance in patients. Hepatic and renal clearance could be successfully predicted for approximately half and two-thirds, respectively, of the applied compounds, showing the high utility of SFs. SFs were also introduced to a physiologically based pharmacokinetic (PBPK) model, and the plasma concentration profiles of 12 model compounds with different elimination pathways were predicted for CKD patients. The PBPK model combined with SFs provided good predictability for plasma concentration. The developed PBPK model with information on SFs would accelerate translational research in drug development by predicting pharmacokinetics in CKD patients.

Suicidal inactivation of human dihydropyrimidine dehydrogenase by (E)-5-(2-bromovinyl)uracil derived from the antiviral, sorivudine

An enzymatic study was performed to clarify the mechanism of 18 acute deaths in patients who had received the new oral antiviral drug, sorivudine (SRV), during anticancer chemotherapy with 5-fluorouracil (5-FU) prodrugs. Human dihydropyrimidine dehydrogenase (hDPD), playing a key role in the liver as the rate-limiting enzyme in catabolism of 5-FU, was expressed in E. coli, purified and incubated in the presence of NADPH with SRV or (E)-5-(2-bromovinyl)uracil (BVU), a metabolite of SRV produced by human gut flora. hDPD was rapidly and irreversibly inactivated by BVU, but not by SRV. Radioactivity of [14C]BVU was incorporated into hDPD in the presence of NADPH in a manner reciprocal to the enzyme inactivation. In the absence of NADPH, hDPD was not inactivated by BVU, nor radiolabeled with [14C]BVU. Thus, as we demonstrated previously with studies using the rat, the acute deaths were strongly suggested to be attributable to markedly elevated tissue 5-FU levels which were responsible for irreversible inhibition of hDPD by covalent binding of a reduced form of BVU as a suicide inactivator.

Characterization of gastrointestinal absorption of digoxin involving influx and efflux transporter in rats: application of mdr1a knockout (-/-) rats into absorption study of multiple transporter substrate

1.  This study was aimed to characterize gastrointestinal absorption of digoxin using wild-type (WT) and multidrug resistance protein 1a [mdr1a; P-glycoprotein (P-gp)] knockout (-/-) rats. 2.  In WT rats, the area under the plasma concentration-time curve (AUC) of oral digoxin increased after oral pretreatment with quinidine at 30 mg/kg compared with non-treatment, but the increasing ratio tended to decrease at a high dose of 100 mg/kg. In mdr1a (-/-) rats, however, quinidine pretreatment caused a dose-dependent decrease in the AUC. 3.  Quinidine pretreatment did not alter the hepatic availability of digoxin, indicating that the changes in the digoxin AUC were attributable to inhibition of the absorption process by quinidine; i.e. inhibition of influx by quinidine in mdr1a (-/-) rats and inhibition of efflux and influx by quinidine in WT rats. 4.  An in situ rat intestinal closed loop study using naringin implied that organic anion transporting peptide (Oatp) 1a5 may be a responsible transporter in the absorption of digoxin. 5.  These findings imply that the rat absorption behavior of digoxin is possibly governed by Oatp1a5-mediated influx and P-gp-mediated efflux. The mdr1a (-/-) rat is therefore a useful in vivo tool to investigate drug absorption associated with multiple transporters including P-gp.

Pharmacokinetics and disposition of dalcetrapib in rats and monkeys

1. The pharmacokinetics and metabolism of dalcetrapib (JTT-705/RO4607381), a novel cholesteryl ester transfer protein inhibitor, were investigated in rats and monkeys. 2. In in vitro stability studies, dalcetrapib was extremely unstable in plasma, liver S9 and small intestinal mucosa, and the pharmacologically active form (dalcetrapib thiol) was detected as major component. Most of the active form in plasma was covalently bound to plasma proteins via mixed disulfide bond formation. 3. Following oral administration of (14)C-dalcetrapib to rats and monkeys, active form was detected in plasma. The active form was mainly metabolized to the glucuronide conjugate and the methyl conjugate at the thiol group. Several minor metabolites including mono- and di-oxidized forms of the glucuronide are also detected in the plasma and urine. 4. The administered radioactivity was widely distributed to all tissues and mainly excreted into the feces (85.7 and 62.7% of the dose in rats and monkeys, respectively). Most of the radioactivity was recovered by 168 h. Although the absorbed dalcetrapib was hydrolyzed to the active form and was bound to endogenous thiol via formation of disulfide bond, it was relatively rapidly eliminated from the body and was not retained.

Unresponsiveness to L-DOPA in parkinsonian patients: a study of homovanillic acid concentration in the cerebrospinal fluid

In this study, concentrations of homovanillic acid (HVA), a principal metabolite of dopamine (DA), in the cerebrospinal fluid (CSF) were measured in 17 patients with Parkinson's disease (PD) who had been effectively treated with L-DOPA and in 8 patients clinically diagnosed as having striatonigral degeneration (SND) and for whom treatment with L-DOPA had proved ineffective. L-DOPA administration, consisting of a daily dosage of 600 mg plus 150 mg aromatic L-amino acid decarboxylase inhibitor was continued in all cases for at least 3 months. In the PD group, the HVA value was 511.6 +/- 196.5 pmol/ml and in the SND group, 144.9 +/- 83.4 pmol/ml. This remarkably low value for the SND group suggests that there may exist severe disorders in the uptake and decarboxylation of exogenous L-DOPA.

Quantitative prediction of OATP1B-mediated drug-drug interactions using endogenous biomarker coproporphyrin I

1. Evaluation of the organic anion transporting polypeptide (OATP) 1B-mediated drug-drug interaction (DDI) potential is important for drug development. The focus of this study was coproporphyrin I (CP-I), an endogenous OATP1B biomarker.2. We investigated a new approach to OATP1B-mediated DDI prediction based on the mechanistic static pharmacokinetics (MSPK) model.3. The ratio of the area under the plasma concentration-time curve (AUCR) with and without co-administration of rifampicin (a typical OATP1B inhibitor) was found for CP-I and OATP1B substrate, respectively, and was then used to derive the correlation curve equation. The AUCR with and without co-administration of another OATP1B inhibitor than rifampicin was then predicted for the OATP1B substrates by substituting the AUCR of CP-I in the correlation curve equation to verify the predictability of the AUCR of the OATP1B substrates.4. The derived correlation curve equation between CP-I and the OATP1B substrates of the AUCRs with and without co-administration of rifampicin matched the observed AUCRs well. Regarding pitavastatin, rosuvastatin and pravastatin, 92.9% of the predicted AUCR values were within a two-fold range of the observed values, indicating that this approach may be a good way to quantitatively predict DDI potential.

Evaluation of the changes in exposure to thiol compounds in chronic kidney disease patients using the PBPK model

Targeted covalent inhibitors designed to bind covalently to a specific molecular target have recently been a focus of drug development. Among these inhibitors, thiol compounds bind covalently to endogenous thiols in the body through a process involving disulfide bonds. We investigated the predictability of changes in the exposure to captopril, tiopronin, the active form of dalcetrapib and the active metabolite of prasugrel, R-138727, all of which have a sulfhydryl group, in moderate and severe chronic kidney disease (CKD) patients using a constructed PBPK model. The changes in the exposure to captopril, tiopronin and the active form of dalcetrapib under CKD conditions were well predicted. However, the change in exposure to R-138727, which is a secondary metabolite of prasugrel, was overpredicted. Although these thiol compounds covalently bind to endogenous thiols, our study concluded that changes in exposure to these compounds under CKD conditions can probably be predicted, except for compounds with a complicated mechanism whereby the thiol metabolite is generated.

The influence of multiple oral administration on the pharmacokinetics and distribution profile of dalcetrapib in rats

We investigated the influence of multiple oral administration on the accumulation of dalcetrapib (JTT-705/RO4607381), a novel cholesteryl ester transfer protein inhibitor, in rats. It is well known that orally administered dalcetrapib is rapidly hydrolysed to its active form, which has a sulfhydryl group, in the body. The active form then binds covalently to endogenous thiols via mixed disulfide bonds. Following multiple once daily oral administration of ¹⁴C-dalcetrapib for seven days to rats, the concentration of radioactivity in the plasma and almost all tissues reached the steady state by day 4. At 24 h after the last dose, there was a relatively high concentration of radioactivity in the mesenteric lymph nodes, liver, adrenal glands and fat. After the last dose to rats, the radioactivity was almost completely recovered in the urine and faeces, indicating that dalcetrapib is not retained in the body, probably due to the reversibility of the disulfide bonds despite being covalent bonds.

Gradient subthalamic neurodegeneration and tau pathology in the hypoglossal nucleus as essential pathological markers of progressive supranuclear palsy - Richardson syndrome

Progressive supranuclear palsy - Richardson syndrome (PSP-RS) was first described in 1964 by Steele et al. Tau pathology has not been reported in the hypoglossal nuclei of PSP-RS patients, whereas Steele et al. described gliosis with no remarkable neuronal losses in the hypoglossal nucleus. This study aimed to investigate the distribution and degree of tau pathology-associated neurodegeneration, with an emphasis on the hypoglossal nucleus, in patients with PSP-RS. Six clinicopathologically proven PSP-RS cases were included in this study. All patients were clinicopathologically and immunohistochemically re-evaluated. This study confirmed the following neuropathological characteristics of PSP-RS: (1) neurodegeneration usually affects the striatonigral system and cerebellar dentate nucleus; (2) the cerebellar afferent system in PSP-RS is affected by absent-to-mild neurodegeneration; and (3) the extent of tau distribution throughout the central nervous system is greater than the extent of neurodegeneration. Furthermore, we found that subthalamic neurodegeneration was more prominent in the ventromedial region than in the dorsolateral region. Nevertheless, the tau pathology showed no remarkable differences between these two sites. Interestingly, the tau pathology was frequently observed in the hypoglossal nuclei of PSP-RS patients. Gradient neurodegeneration of the subthalamus and tau pathology in the hypoglossal nucleus could be regarded as essential pathological features of PSP-RS.

[A 65-year-old man with Parkinsonism, gaze palsy, and dementia]

We report a 65-year-old man with parkinsonism, supranuclear gaze palsy, and dementia. The patient was well until 58 years of the age (1984) when he noted an onset of tremor in his right hand. He visited our neurology service two years after the onset; neurologic examination at that time revealed moderate restriction in down ward gaze, horizontal gaze nystagmus in left and right gaze, stooped posture with loss of arm swing when he walked, slight rigidity in the neck and the right upper and lower extremities, and resting tremor in his right hand and foot; mentation was intact. He was treated with 600 mg of levodopa with carbidopa; his tremor partially improved. He received left Vim thalamotomy on March 14 of 1987. His tremor disappeared after the thalamotomy. Post-operative course was complicated by transient clouding of consciousness due to subdural hematoma which developed after the surgery. Six months after the surgery, he noted increase in the unsteadiness of gait; he also experienced urinary incontinence once in a while, and he became mentally dull. In November of 1988, he had episodes of stiffening of his body. Although his spontaneous speech was very much reduced, he repeatedly hummed a same tune; no one could make him stop humming. In June of 1989, he was totally unable to move his eyes in the vertical direction. He was hospitalized to another hospital in May of 1990 where he died six month after admission because of pneumonia. The clinical course of this patient was characterized by the onset with parkinsonian resting tremor, and supranuclear gaze palsy and dementia in the later course. The patient was discussed in a neurological CPC and the chief discussant arrived at the conclusion that the patient had an overlap syndrome of progressive supranuclear palsy (PSP) and diffuse Lewy body disease. Majority of the participants thought that the patient had progressive supranuclear palsy, but many of them had an impression that parkinsonian tremor responding to levodopa as the initial symptom for PSP is rather unusual. Postmortem examination revealed severe loss of neurons in the substantia nigra, the globus pallidus, and the subthalamic nucleus with reactive gliosis; formy spheroids were seen in the substantia nigra, however, no Lewy bodies or neurofibrillary tangles were observed. Moderate neuronal loss was also seen in the dentate nucleus of the cerebellum. In addition, the precentral gyrus showed moderate neuronal loss, astrocytosis, and spongy change in the second layer; ballooned neurons were seen in the third and the fifth layers. Histologic characteristics were consistent with the pathologic diagnosis of corticobasal degeneration.

[A 74-year-old woman with parkinsonism and dementia who died four years after the onset]

We report a 74-year-old woman with parkinsonism and dementia, who died 4 years after the onset of the disease. She was well until 70 years of the age (1993) when she noted slowness in the movement in her left hand. She also developed gait disturbance and the similar symptoms spread to the right upper and lower extremities. Two years after the onset, she had difficulty in walk, and was admitted to our hospital on March 9, 1995. Her daughter had the onset of hand tremor at 50 years of the age and gait disturbance at 52. Her gait improved after levodopa treatment, but her MRI revealed a liner T2-high signal lesion along the outer surface of each putamen. On admission, the patient was alert but slighted demented. Higher cerebral functions were normal. She had a masked face and small voice. Her gait was of small step without arm swing. Retropulsion was present. Rigidity was noted in the neck but not in the limbs. She was bradykinetic but tremor was absent. She was treated with levodopa/carbidopa, dops, and bromocriptine with considerable improvement and was discharged on March 30, 1995. On January 19, 1996, she developed fever and hallucination; she became more akinetic and admitted again. She showed marked dementia and stage IV parkinsonism. She was treated by supportive measures with improvement in the general condition, but she was found to have a gastric cancer for which a subtotal gastrectomy was performed on March 11, 1996. Post-operative course was uneventful, but her parkinsonism progressed to stage V. She was transferred to another hospital on May 13, 1996. In July 21, 1996, she developed dyspnea and fever and was admitted to our hospital again. She was somnolent. Rigidity was moderate to marked and she was unable to stand or walk. By supportive cares, her general condition improved and was discharged to home on November 4, 1996. She developed fever on June 13, 1997 and admitted to our service again. Her BP was 150/90 mmHg. She was alert but markedly demented. Laboratory examination revealed increases in liver enzymes (GOT 75 IU/l, GPT 101 IU/l) and renal dysfunction (BUN 68 mg/dl, creatinine 3.27 mg/dl). Subsequent hospital course was complicated by renal failure and thrombocytopenia (33,000/ml). She expired on July 1, 1997. The patient was discussed in a neurologic CPC, and a chief discussant arrived at the conclusion that the patient had diffuse Lewy body disease and her daughter striatonigral degeneration. Some participants thought both the patient and her daughter had diffuse Lewy body disease. Post-mortem examination revealed marked degeneration of the substania nigra and the locus coeruleus. The medial part of the nigra also showed marked cell loss. Lewy bodies were found in the remaining nigral and coeruleus neurons. Cortical Lewy bodies were very few and the striatum was intact. Pathologic diagnosis was Parkinson's disease. Dementia was in part attributed to the marked degeneration of the medial part of the substantia nigra.

[Treatment and prognosis of juvenile parkinsonism--L-dopa responsiveness]

The treatment and prognosis of juvenile parkinsonism(JP) with onset under the age of 40 years is described. The patients with JP responded better to L-dopa and more gradual progression of symptoms, but, developed dopa-induced dyskinesias and motor fluctuations earlier and more frequently than Parkinson's disease patients. In order to control the dyskinesias and motor fluctuations, a small dose of L-dopa has to be administered several times a day with the combination of dopamine-receptor agonists. As a result of the increased life expectancy with L-dopa treatment the mean duration of the disease has increased in Parkinson's disease and JP, however, mean age at death in JP was still under 60.

[A 62-year-old man with familial parkinsonism with the onset at 24 years of the age]

We report a right-handed 62-year-old man with early onset familial parkinsonism. The patient was well until 24 years of the age when he noted an onset of resting tremor in his right hand. During the next four years, he noted rigidity, bradykinesia, and difficulty in walking. He was seen in another hospital at 28 years of the age, where he received left pallidotomy. Rigidity on the left side showed marked improvement. He received right pallidotomy at age 30 years. He developed right hemiplegia after this surgery. He was admitted to our hospital in March, 1983 when he was 51 years of the age. He was treated with levodopa but improvement was rather of minor degree. He was transferred to another hospital, but his motor disturbance progressed slowly, and was admitted again to our hospital in November 1990. He had 6 siblings 4 of whom including himself suffered from parkinsonism. No consanguinity was noted in parents. On admission, he appeared chronically ill but the general physical examination was unremarkable. Neurologic examination revealed an alert and mentally sound man. Hasegawa dementia scale was 28.5/32.5. Upward gaze was slightly restricted (3/5). Cranial nerve examination revealed oculogyric crisis, apraxia of eyelid opening, masked face, and small voice. He was able to stand with support; his posture showed left-ward leaning. He had right hemiparesis with moderate weakness. He showed marked bradykinesia and moderate rigidity in his left upper extremity. Fine postural tremor was noted in the left hand. Deep tendon reflexes were diminished in the upper extremities. No Babinski sign was noted. Pain sensation was somewhat diminished on the right side. Results of routine laboratory examination were unremarkable. Cranial CT scan revealed atrophy in the frontal lobe, particularly in the prefrontal area. In addition, MRI revealed T1-and-T2-low signal intensity lesions in the right ventral pallidal region and in the left ventrolateral thalamic-hypothalamic areas. He was treated with 600 mg of levodopa with benserazide and 22.5 mg of bromocriptine with mild to moderate improvement in his bradykinesia and rigidity. He was discharged in January 1991. His clinical course was complicated by intestinal obstruction in October, 1994. He was admitted to another hospital where he was operated on the obstruction on November 5, 1994. The sigmoid colon was markedly dilated but no mass was found. Postoperative course was uneventful until November 18, 1994 when he was found dead in his hospital room shortly after 4 am. The patient was discussed in neurological CPC, and the chief discussant arrived at the conclusion that the patient had young-onset familial Lewy body-negative parkinsonism. Opinions were divided between Lewy body-positive familial Parkinson's disease and Lewy body negative young onset parkinsonism. Postmortem examination revealed aspiration pneumonia, which appeared to be the cause of his death, in the right lung. Neuropathologic examination revealed loss of malanized neurons in the substantia nigra and the locus coeruleus. In the substantia nigra, neuronal loss was particularly severe in the ventrolateral area. No Lewy bodies were seen. The dorsal motor nucleus of the vagal nerve was well preserved. Stereotaxic lesions involved bilateral thalamic areas. This patient appears to represent a case of autosomal recessive juvenile parkinsonism (AR-JP). Early onset, superb response to levodopa, sleep effect, and easy development of dyskinesias and motor fluctuations characterize AR-JP. The reason why this patient did not show these clinical features is probably bilateral sterotaxic surgeries. Particularly, the second surgery was complicated by right hemiparesis. His siblings who developed parkinsonism showed typical clinical features of AR-JP.

[A 62-year-old man with an acute onset of consciousness disturbances]

We report a 62-year-old man who developed coma and died in a fulminant course. The patient was well until May 1, 1996 when he noted chillness, tenderness in his shoulders, and he went to bed without having his lunch and dinner. In the early morning of May 2, his families found him unresponsive and snoring; he was brought into the ER of our hospital. He had histories of hypertension, gout, and hyperlipidemia since 42 years of the age. On admission, his blood pressure was 120/70, heart rate 102 and regular, and body temperature 36.3 degrees C. His respiration was regular and he was not cyanotic. Low pitch rhonchi was heard in his right lower lung field. Otherwise general physical examination was unremarkable. Neurologic examination revealed that he was somnolent and he was only able to respond to simple questions such as opening eyes and grasping the examiner's hand, but he was unable to respond verbally. The optic discs were flat; the right pupil was slightly larger than the left, but both reacted to light. He showed ptosis on the left side, conjugate deviation of eyes to the left, and right facial paresis. The oculocephalic response and the corneal reflex were present. His right extremities were paralyzed and did not respond to pain Deep tendon reflexes were exaggerated on the right side and the plantar response was extensor on the right. No meningeal signs were present. Laboratory examination revealed the following abnormalities; WBC 18,400/ml, GOT 131 IU/l GPT 50 IU/l, CK616 IU/l, BUN 30 mg/dl, Cr 2.1 mg/ dl, glucose 339 mg/dl, and CRP 27.4 mg/dl. ECG showed sinus tachycardia and ST elevation in II, III and a VF leads and abnormal q waves in I, V5, and V6 leads. Chest X-ray revealed cardiac enlargement but the lung fields were clear. Cranial CT scan revealed low density areas in the left middle cerebral and left posterior cerebral artery territories. The patient was treated with intravenous glycerol infusion and other supportive measures. At 2: 10 AM on May 3, he developed sudden hypotension and cardiopulmonary arrest. He was pronounced dead at 3:45 AM. The patient was discussed in a neurological CPC, and the chief discussant arrived at the conclusion that the patient had acute myocardial infarction involving the inferior and the true posterior walls and left internal carotid embolism from a mural thrombus. Post mortem examination revealed occlusion of the circumflex branch of the left coronary artery due to atherom plaque rupture and myocardial infarction involving the posterior and the lateral wall with a rupture in the postero-lateral wall. Marked atheromatous changes were seen in the left internal carotid, the middle cerebral and the basilar arteries; the left internal carotid and the middle cerebral arteries were almost occluded by thrombi and blood coagulate. The territories of the left middle cerebral and the occipital arteries were infarcted; but the left thalamic area was spared. The neuropathologist concluded that the infarction was thrombotic origin not an embolic one as the atherosclerotic changes were severe. Cardiac rupture appeared to be the cause of terminal sudden hypotension and cardiopulmonary arrest. It appears likely that a vegetation which had been attached to the aortic valve induced thromboembolic occlusion of the left internal carotid artery which had already been markedly sclerotic by atherosclerosis. It is also possible that the vegetations in the aortic valve came from mural thrombi at the site of acute myocardial infarction, as no bacteria were found in those vegetations.

[A long-term clinical effect of selegiline hydrochloride on Parkinson's disease]

A long-term follow-up evaluation on the clinical usefulness of selegiline hydrochloride (selegiline) was performed in 13 patients with Parkinson's disease. All patients, except one case, subjected to the study were symptomatically improved by combination therapy of selegiline with L-DOPA in the preceding short-term evaluation. One patient continued the therapy after an evaluation of no symptomatic improvement in the short-term study, because this patient strongly requested continuation of medication, expecting to stop the progression of the disease. The average daily dose of selegiline at the last evaluation was 7.0 +/- 2.8 mg. The average daily dose of L-DOPA at each evaluation point in the patients who continued the therapy for 12 months remained low compared to that prior to the therapy (before: 450 +/- 138 mg, at the 12th month: 383 +/- 98 mg). In the analysis of individual parkinsonian symptoms, the improvement in the mean score for most of the symptoms, especially the wearing-off phenomenon and frozen gait, persisted for the entire period of study. Global improvement rates (moderately improved) at the 6th and 12th month, and the last evaluation were 60.0%, 50.0% and 50.0%, respectively. Among 10 patients, therapy was discontinued only in one case due to hallucination. Although the global improvement rate declined in the course of the therapy, selegiline seems to be useful for improving L-DOPA responsive symptoms in long-term therapy for Parkinson's disease.

[A 85-year-old woman with one year history of convulsion, dementia, and consciousness disturbance]

We report a 85-year-old woman who died after one year history of convulsion, dementia, and consciousness disturbance. She was apparently well until January 6, 1995 when she was 85 year old; on that evening, she suddenly stated that some one was in her room and she became confused. A local MD gave her diazepam and she fell into sleep. At 3 o'clock in the following morning, she developed tonic-clonic convulsion in her right lower extremity which showed a march to her right upper extremity and the left lower extremity. She was admitted to our hospital. On admission, she was comatose with respiratory acidosis. She was intubated and placed on a ventilator. She was treated with intravenous phenytoin. She gradually gained consciousness and became alert. Respiration became normal. Her MRI revealed ventricular dilatation, fronto-parietal cortical atrophy, and a T1-low and T2-high signal intensity lesion in the left occipital lobe. She was discharged for out patient follow-up on February 4, 1995. Since then, she noted loss of memory and small step gait. A follow-up CT scan revealed a mass lesion which showed a ring-shaped enhancement in the left occipital lobe and was admitted again. On admission, she was alert but markedly demented. The optic fundi was unremarkable, but she appeared to have right homonymous hemianopsia. No motor weakness was noted. In Gd-DTPA enhanced MRI, the above tumor showed a ring enhancement. The diagnosis of glioblastoma was entertained, however, considering her age, she was treated with intravenous glycerol and intramuscular steroid. She was discharged for out-patient follow-up on July 15, 1995. Her gait disturbance had progressively become worse and she developed nausea and vomiting and was admitted again on October 2, 1995. On admission, she was somnolent and markedly demented. Brain stem responses were retained normally. She was unable to stand or walk. Deep tendon reflexes were slightly increased in the right upper extremity and the plantar response was extensor on the right. Her hospital course was complicated by respiratory tract infection and respiratory acidosis. She expired on November 2, 1995. The patient was discussed in a neurological CPC and the chief discussant arrived at the conclusion that she had a glioblastoma involving the left occipital lobe and the adjacent areas. Post-mortem examination revealed an infiltrating tumor in the left occipital lobe. On microscopic examination, the tumor was very cellular; nuclear atypism was marked and tumor cells undergoing mitosis were seen. In some areas, capillary proliferation was seen. Histologic characteristics were consistent with glioblastoma.

[A 29-year-old man with diabetes insipidus and cerebellar ataxia and development of spinal cord swelling 15 years after the onset]

We report a 29-year-old man with diabetes insipidus and cerebellar ataxia who developed spinal cord swelling 15 years after the onset. He was well until 14 years of the age when he noted dizziness. Two years after there was an onset of gait disturbance and slurred speech. He also noted polydipsia and polyuria. He was evaluated at the neurosurgery service of our hospital when he was 17 years of the age. Neurologic examination at that time revealed memory loss, horizontal nystagmus, cerebellar ataxic gait, dysmetria and decomposition more on the left. Cranial CT scan revealed a mass lesion involving the left subthalamic region and the head of the caudate area. Spinal fluid was unremarkable, however, human chorionic gonadotropin was increased to 27 mIU/ml. He was treated by radiation therapy (3,000 rads for total brain area and 5,460 rads for focal region). His CT scan and memory loss improved, however, cerebellar ataxia was unchanged. Three years after the radiation, he started to show choreic movement in his neck and left upper extremity. He was admitted to our service in August 14, 1995 when he was 29 years of the age. On admission, he was alert but disoriented to time; calculation was also poor. Higher cerebral functions were intact. The optic fundi were normal without papilledema. Visual field appeared intact. Gaze nystagmus was observed in all the directions, but more prominent in the horizontal direction. Speech was slurred. Otherwise, cranial nerves were unremarkable. Motor wise, he showed marked truncal and gait ataxia; he was unable to walk because of ataxia. Muscle atrophy and marked weakness was noted in both upper extremities more on the left side. Deep tendon reflexes were diminished in the upper extremities but active in the lower extremities. He was polyuric; urinary specific gravity was low. Spinal fluid contained 6 cells/cmm and 113 mg/ dl of protein; Queckenstedt was positive. MRI revealed swelling of the cervical cord; in addition, the entire cervical region and the medullar oblongata appeared as high signal intensity areas. No mass lesion was noted in the supratentorial structures but the third ventricle was markedly enlarged. Surgical biopsy was performed on the cervical lesion. The patient was discussed in neurologic CPC, and the chief discussant arrived at the conclusion that the patient had germinoma with syncytiotrophoblastic giant cells in the diencephalic region which appeared to have been cured by radiation therapy; he thought that the cervical lesion was the seeding of germinoma. Cerebellar ataxia was ascribed to the remote effect of germinoma. Most of the participants thought that the original tumor was germinoma and the cervical lesion was its spread. Some participants thought that his ataxia was caused by germinoma cells involving the medulla and the inferior cerebellar peduncles. Histologic observation of the biopsied tissue from the spinal cord revealed the typical two cell patterned germinoma. Most of the tumor cells were not stained for an antibody against HCG, but some tumor cells were positively stained. Germinoma is very radio-sensitive; this patient showed T2 high signal lesion involving the medulla oblongata and cervical cord continuously. Probably, tumor cells in the lower brain stem escaped radiation, and gradually spread to the spinal cord over many years. At the time of operation, the surface of the spinal cord was free from tumor cells. Therefore, tumor cells invaded the spinal cord continuously from the medulla oblongata. He was treated with cervical radiation, and his neurologic as well as radiologic findings showed marked improvement.

[A 45-year-old man with peripheral monocytosis and right hemiparesis]

We report a 45-year-old man with monocytosis and right hemiparesis. The patient suffered from an acute myocardial infarction from which he recovered completely when he was 42 years old. One year prior to his death, he was found to have increase in monocyte count (35.5% of leukocytes) in peripheral blood and splenomegaly; he was admitted to the hematology service of our hospital. He was diagnosed as having chronic myelomonocytic leukemia after bone marrow examination. He was treated with radiation therapy with improvement in splenomegaly. In May of 1995, he had fever, anemia, and thrombocytopenia for which he needed daily blood transfusion. In November of 1995, he had an onset of weakness in his right hand, and neurologic consultation was asked for in November 27, 1995. Neurologic examination revealed a chronically ill japanese man in no acute distress. He was alert and not demented. Higher cerebral functions were intact. Cranial nerve examination revealed right facial paresis of the central type. Motor-wise, he was right hemiparetic. Generalized muscle wasting was noted apparently due to the chronic debilitating disease. Deep tendon reflexes were within normal range in the right upper extremity, but were diminished in other areas. Sensation was intact, and no meningeal signs were noted. Pertinent laboratory findings were as follows: Hb 8 g/dl, RBC 238 x 10(4)/microliter, WBC 2,900/microliter (band 1.0%, seg 18.5%, lym 28.0%, mono 44.0%, Baso 2.5%), Plt 13 x 10(4)/microliter, PT 16.6"/10.9", APTT 44.7"/35.0". CSF contained 87 mg/dl of protein, 155 mg/dl of glucose and 2 mononuclear cells/microliter. Bone marrow was slightly hypercellular with mild increase in blast forms. No chromosome abnormality was found. CT and MRI revealed a large mass in the left fronto-parietal region and the meninges showed marked thickening with enhancement after gadolinium-DTPA in MRI. The patient was treated with glycerol and steroid, but the subsequent course was complicated by a seizure, agitation, and pneumonia. He died from respiratory failure on January 13, 1996. The patient was discussed in a neurologic CPC and the chief discussant arrived at the conclusion that the patient had chronic myelomonocytic leukemia with infiltration of leukemic cells into meninges and the parenchyme of the cerebrum. Thickening of the dura was thought to be in part a reaction to the subdural hematoma as well as to leukemic cells along the meninges. Postmortem examination revealed hypercellular bone marrow with increase in monocytic cells (more than 20%). The lungs showed pneumonia with scattered old tuberculous lesions. The heart showed an old myocardial infarction in the posterior wall of the left ventricle. The brain showed an old chronic subdural hematoma in the left fronto-temporal region and a cystic mass lesion in the left frontoparietal region. The mass was hypercellular and most of them were monocytes. The dura mater showed reactive thickening without leukemic cell infiltration. It was concluded that this patient had chronic myelomonocytic leukemia with a formation of leukemic mass in the brain. Pathologists thought that the mass was a hematogenous spread. It is rare for chronic myelomonocytic leukemia to form a mass lesion in the brain.

[A 96-year-old man with consciousness disturbance, convulsion, and left hemiplegia of acute onset]

We report a 96-year-old Japanese man who developed a sudden onset of left hemiplegia and coma. He was found to have diabetes mellitus, hypertension, and atrial fibrillation since 1996 with occasional episodes of congestive heart failure. He was otherwise apparently well until July 5 of 1997 when he developed a sudden onset of unresponsiveness and convulsion involving his right hand and was admitted to our hospital. On admission, his BP was 210/120 mmHg, heart rate 76/min and irregular, BT 36.5 degrees C, and Cheyne-Stokes respiration. General medical examination was otherwise unremarkable. Neurologic examination revealed semicoma, conjugated deviation to the right, loss of oculocephalic response, left facial paresis of central type, flaccid left hemiplegia, and bilateral Babinski sign. Pertinent laboratory findings are as follows: BUN 47 mg/dl, creatinine 1.46 mg/dl, GPT 69 IU/l, LDH 1,142 IU/l, and CK 385 IU/l. A chest x-ray film revealed cardiac enlargement and EKG showed left ventricular hypertrophy and atrial fibrillation. Cranial CT scan revealed low density areas involving the right anterior cerebral and the right posterior cerebral artery territories. He was treated with an intravenous osmotic agent and short course of intramuscular steroid. He remained unconscious despite these treatment and developed sudden cardiopulmonary arrest three weeks after the admission. The patient was discussed in a neurological CPC and the chief discussant arrived at the conclusion that the patient had suffered from cerebral embolism of cardiac origin. The cause of the death was ascribed to acute subendocardial myocardial infarction. Most of the participants agreed with this conclusion. Postmortem examination revealed an old subendocardial myocardial infarction involving the posterior septal region and posterolateral wall of the left ventricle. Neuropathologic examination revealed hemorrhagic infarctions involving the territories of the right anterior cerebral, right middle cerebral, right posterior cerebral, and left anterior cerebral arteries. The left A1 portion of the anterior cerebral artery was hypoplastic, and the left pericallosal artery appeared to have been receiving blood supply from the right anterior cerebral artery through the anterior communicating artery. The large arteries in the base showed marked arteriosclerosis; particularly, the initial portion of the right posterior artery showed near complete arteriosclerotic occlusions. These characteristic arterial changes appeared to be the reason why this patient suffered from an extensive infarction from what appeared to have been a single episode of cerebral embolism probably initially involving the right internal carotid artery.

[A long-term clinical effect of selegiline hydrochloride on Parkinson's disease]

A long-term follow-up evaluation on the clinical usefulness of selegiline hydrochloride (selegiline) was performed in 13 patients with Parkinson's disease. All patients, except one case, subjected to the study were symptomatically improved by combination therapy of selegiline with L-DOPA in the preceding short-term evaluation. One patient continued the therapy after an evaluation of no symptomatic improvement in the short-term study, because this patient strongly requested continuation of medication, expecting to stop the progression of the disease. The average daily dose of selegiline at the last evaluation was 6.9 +/- 2.5 mg. The average daily dose of L-DOPA at each evaluation point in the patients who continued the therapy for 12 months remained low compared to that prior to the therapy (before: 450 +/- 117 mg, at the 12th month: 389 +/- 89 mg). In the analysis of individual parkinsonian symptoms, the improvement in the mean score for most of the symptoms, especially the wearing-off phenomenon and frozen gait, persisted for the entire period of study. Global improvement rates (moderately improved) at the 6th and 12th month, and the last evaluation were 61.5%, 44.4% and 46.2%, respectively. Among 13 patients, therapy was discontinued only in one case due to hallucination. Although the global improvement rate declined in the course of the therapy, selegiline seems to be useful for improving L-DOPA responsive symptoms in long-term therapy for Parkinson's disease.