Cerebral protective effect of flunarizine in a canine model of cerebral ischaemia

To test the effect of flunarizine on cerebral ischaemia, 15 dogs were subjected to ischaemia, using the 'canine model of the completely ischaemic brain regulated with a perfusion method' in which the cerebral blood flow (CBF) can be fully regulated. Five animals served as untreated controls, 10 received flunarizine, a calcium antagonist (1 mg/kg in 5 dogs and 3 mg/kg in 5 dogs), before the ischaemic period. After 1 h CBF was restored and recovery of the electrical activity of the brain and the degree of brain swelling were observed for 3 h. At the end of the experiments, the degree of extravasation of Evans blue was examined. Remarkable recovery of EEG was found in the groups given flunarizine when compared with untreated controls. However, no significant difference was found between untreated controls and flunarizine treated groups for the degree of brain swelling and the degree of extravasation of Evans blue. These results suggest that the treatment of flunarizine is of benefit for functional recovery against cerebral ischaemia, but does not suppress ischaemic brain oedema.

Bifrontal interhemispheric approach for carotid-ophthalmic aneurysms

The authors report their experience with the surgical treatment of carotid-ophthalmic aneurysms in 29 cases, and describe their surgical technique. The technique can be summarized as follows. When dissecting the aneurysm, temporary vascular occlusion of the common carotid artery and external carotid artery is done in the neck under the administration of cerebral protective substances. Through a bifrontal craniotomy, wide dissection of the Sylvian fissures and the interhemispheric fissure is performed. When necessary, the anterior clinoid process and the roof of the optic canal are removed. This approach allows for observation of the neck of the aneurysm from various angles, thus facilitating clipping of the neck. There have been no previous reports of direct surgery on carotid-ophthalmic aneurysms using an interhemispheric approach, but this approach provides a much larger operative field and a better exposure of the aneurysm than other surgical approaches.

[Distribution patterns of hypertrophy at the apical level in patients with giant negative T waves: identification by magnetic resonance imaging]

To clarify the distribution patterns of hypertrophy at the apical level in patients with giant negative T waves (GNT), ECG-gated magnetic resonance imaging (MRI) was performed in 10 patients with GNT and in five normal controls. End-diastolic left ventricular short-axis images at the basal and apical levels were obtained in all subjects. Thicknesses of the septal, anterior, lateral and posterior walls at these two levels were measured and distribution of hypertrophied myocardium (more than or equal to 15 mm) at the apical level was examined. The ratio (R) of the maximal thickness at the apical level over that at the basal level was calculated. In normal subjects, the mean apical wall thickness was 8.7 +/- 1.9 mm. In the GNT group, the wall thickness was always greater than the mean value +3 SD of the normal control, and there were no differences among the four segmental walls. The hypertrophic portions at the apex were circumferential in three, septal-anterior-lateral in two, septal-anterior in two, septal in one, anterior in one and lateral in one. In patients with GNT, the average maximal thickness at the apical level was 19.3 +/- 3.2 mm; by location, four cases in the septum, four in the anterior wall and two in the lateral wall, and the average minimum thickness was 11.7 +/- 3.7 mm; all in the posterior wall. The R was more than 1.3 in nine patients with GNT and less than 1.0 in all normal subjects. In conclusion, there was a variety of patterns of apical hypertrophy, and the R greater than or equal to 1.3 was characteristic in patients with GNT.

[A case of cavernous angioma extended from the ventral part of the pons to the midbrain: subtemporal and trans-tentorial approach]

The authors presented a surgically treated case of cavernous angioma extending from the ventral part of the pons to the midbrain. A 20-year old man was admitted to our service with left motor weakness, dysarthria and consciousness disturbance. CT scan revealed a round well-circumscribed high density lesion in the pons and midbrain. This was diagnosed preoperatively as a cryptic vascular malformation with hemorrhage. The right temporal craniotomy with keel form skin incision and subtemporal & trans-tentorial approach was performed in an attempt to remove the hematoma and the angioma. Histological examination of the surgical specimen revealed abnormal vessels as a cavernous angioma. The postoperative course was uneventful.

Heterogeneity of hemolytic efficiency and isoelectric point of streptolysin O

Using thin-layer agarose gel isoelectric focusing overlaid with thin-layer erythrocyte agar plates, we found that crude streptolysin O (SLO) consisted of a variety of hemolytic components with different isoelectric points (pIs) and that the distribution of pIs in crude SLO was different even in samples which were produced from a single strain of Streptococcus pyogenes under similar conditions. All of the hemolytic components in crude SLO were shown to have the properties of SLO with respect to their susceptibility to oxygen and anti-SLO serum and their molecular weight. The SLO components showed a single molecular weight of 64,000, but they exhibited various pIs ranging from pH 5.4 to 8.3, with major components showing a pI of 6 and/or 7.5. Further examination revealed the slope of the hemolytic titration curve to be dissimilar among the samples of crude SLO. Since the slope of the hemolytic titration curve of a component appears to be based on its hemolytic efficiency, the value of the slope was designated its hemolytic efficiency index. When SLO was purified by isoelectric focusing, the pI of the components was correlated with its hemolytic efficiency index; hemolytic components with lower pIs exhibited a lower hemolytic efficiency index. These results indicate that SLO consists of heterogeneous components with different pIs and suggest that the differences in hemolytic efficiency indices of SLO components are due to the different electrical charges of SLO molecules, which are related to their polymerization and affect hemolytic efficiency.

A novel sodium channel inhibitor from Conus geographus: purification, structure, and pharmacological properties

A novel toxin, tentatively named conotoxin GS (CGS), has been isolated from a marine snail, Conus geographus. CGS was found to exist as a single polypeptide chain, consisting of 34 amino acid residues, cross-linked by three disulfide bonds. Its amino acid sequence was shown to be Ala-Cys-Ser-Gly-Arg-Gly-Ser-Arg-Cys-Hyp-Hyp-Gln-Cys-Cys-Met-Gly-Leu-Arg- Cys-Gly - Arg-Gly-Asn-Pro-Gln-Lys-Cys-Ile-Gly-Ala-His-Gla-Asp-Val. In competition experiments, CGS inhibited the bindings of [3H]Lys-tetrodotoxin ([3H]Lys-TTX) and [3H]propionylconotoxin GIIIA to Electrophorus electricus electroplax membranes, with Ki values of 34 nM and 24 nM, respectively. The toxin inhibited the binding of [3H]Lys-TTX (1 nM) to rat skeletal muscle homogenates with an IC50 value of 880 nM but showed very little effect on this binding to the rat brain P2 fraction at 10 microM. These binding studies indicate that CGS belongs to the same group of Na channel inhibitors as TTX, STX (saxitoxin), and mu-conotoxins. Although CGS, like the mu-conotoxins, is a pharmacological probe for distinguishing between neuronal and muscle Na channel subtypes, the homology in the sequences of CGS and mu-conotoxins is very limited.

Influence of liver dysfunction on volume of putaminal hemorrhage

We studied the relations of age, sex, hypertension, alcohol consumption, liver dysfunction, and thrombocyte count to the volume of the hematoma in 141 patients with spontaneous putaminal hemorrhage. Hematomas were significantly larger in men, regular alcohol consumers, those with liver dysfunction, and those with low platelet counts. Our findings reflect the fact that almost all of the alcohol consumers were men, most of them had liver disorders, and the volume of hematoma in such patients was relatively large.

Spontaneous intracerebral hemorrhage and liver dysfunction

We evaluated liver function and coagulation parameters in 117 patients with spontaneous intracerebral hemorrhage (68 men and 49 women) admitted to our clinic within 24 hours after onset. Liver dysfunction was more common among men than women due to differences in alcohol consumption. Number of thrombocytes and fibrinogen concentrations were lower, especially among men with elevated concentrations of glutamic oxaloacetic transaminase or glutamic pyruvic transaminase and/or elevated gamma-globulin fraction. Five of the 78 patients undergoing stereotactic hematoma aspiration and one of the 39 treated nonsurgically rebled. All six of the patients who rebled were men, heavy alcohol consumers with liver dysfunction. Fibrinogen concentration was abnormally low in four of the six and at the lower end of the normal range in one. Two showed thrombocytopenia and one case showed prolonged prothrombin time. These facts suggest that liver disorders produce a state in which hemorrhage occurs more readily and that this hemorrhagic tendency may be one of the causal factors of spontaneous intracerebral hemorrhage.

[Phonocardiographic and two-dimensional and pulsed Doppler echocardiographic studies of Still's murmurs]

The prevalence of Still's murmur was examined by phonocardiographic study, and the clinical significance of this murmur was investigated using pharmacodynamic phonocardiography and echocardiography. Still's murmur was present in 224 of 9,478 cases (2.4%) in school children. Its prevalence was 143 in 4,524 (3.2%) in elementary school children and this was significantly greater than that in middle school youngsters who numbered 81 among 4,954 (1.6%) (p less than 0.001). There were neither abnormal findings on two-dimensional echocardiography, nor pathological regurgitant signals on pulsed Doppler examination. After the inhalation of amyl nitrite, Still's murmur was accentuated by 5.3 +/- 3.0 dB, and was louder in the expiratory than in the inspiratory phase by 4.7 +/- 3.5 dB.

[Correlation of left ventricular outflow obstruction with mitral regurgitation]

Our previous study of mitral regurgitation in obstructive hypertrophic cardiomyopathy suggested that left ventricular outflow obstruction due to systolic anterior motion of the distal residual anterior mitral leaflet may hydrodynamically induce mid-systolic mitral regurgitation. To test this hypothesis, we examined whether drug-induced left ventricular outflow obstruction in dogs might cause mitral regurgitation. Dobutamine, 20-60 micrograms/kg/min, induced the obstruction due to mitral systolic anterior motion with mitral-septal contact in 11 of 18 dogs. Pulsed Doppler and contrast echocardiography demonstrated that mitral regurgitation was concomitantly induced in the 11 dogs. The regurgitation was prominent during mid-systole from the onset to the end of mitral-septal contact. Two-dimensional echocardiography showed reduction of the mitral annular dimension and anterior shifts of the mitral valve coaptation during drug infusion in the 11 dogs. Accordingly, the distal portion of the mitral valve, especially of its anterior leaflet, became residual, and moved anteriorly in early systole and protruded into the outflow tract during mid-systole. Catheter-tip pressure recordings simultaneous with two-dimensional echocardiographic observation revealed that the outflow pressure gradient occurred across the protruding distal residual mitral valve. The onset and the end of the pressure gradient were nearly simultaneous with those of the mitral-septal contact. After cessation of the infusion, the mid-systolic mitral regurgitation disappeared together with the obstruction. These results indicate a close relationship between left ventricular outflow obstruction and mid-systolic mitral regurgitation, and strongly support the hypothesis that the obstruction due to systolic anterior motion of the distal residual anterior mitral leaflet is responsible for mitral regurgitation.

The protective effect of mannitol, vitamin E and glucocorticoid on ischaemic brain injury: evaluation by chemiluminescence, energy metabolism and water content

We currently have used three drugs in combination [mannitol, vitamin E and glucocorticoid (beta-methasone)] for the treatment of cerebral infarction in the acute stage. For the purpose of evaluating the efficacy of this therapy, we have conducted experiments evaluated by chemiluminescence (CL), energy metabolism and water content of the cortex using a global highly ischaemic rat brain. During the ischaemic period, CL levels increased with time and further increases were seen after recirculation of the blood flow. However, in the group which was administered the three drugs in combination, there was marked inhibition of CL value. Determination of adenine nucleotide and carbohydrate levels revealed that these drugs in combination promoted their recovery at the time of recirculation following ischaemia. In particular, the increase in lactate was inhibited during the ischaemia, thus preventing the progression of lactic acidosis. Moreover, in the group given all three drugs and in the group given 20% or isotonic mannitol, the increase in cortical water content following recirculation was inhibited. From these results it is deduced that these three drugs inhibit the cellular destruction by attenuation of free radical mediated peroxidation.

[Twenty-six cases regarding the proximal anterior cerebral artery]

The authors report twenty-six aneurysms of the proximal anterior cerebral artery (A1 segment). Fourteen cases were male and twelve cases were female. Saccular aneurysms were twenty-four and fusiform aneurysms were two. The incidence of the A1 aneurysms was 0.76%. Clinicopathologically, multiplicity of this aneurysm was distinctive, and eleven cases had multiplicity (42.3%). In the seven cases among them, the A1 aneurysms bled (63.6%). These 26 aneurysms were classified into five types according to the mode of the origin of the aneurysm from the A1 segment: (a) fifteen aneurysms originating from the junction of the A1 segment and the small perforating artery, (b) five from the A1 directly, (c) three from the proximal end of the fenestration of the A1, (d) two were fusiform aneurysms, (e) one from the junction of the A1 and the cortical branch. In CT scan of these aneurysms, bleeding extending to the septum pellucidum is very similar to that of the anterior communicating artery aneurysms.

Lack of effect from a single cigarette challenge on bronchial responsiveness in healthy non-smoking subjects

The effect of smoking a cigarette on bronchial responsiveness was studied in healthy non-smokers. Twenty two subjects performed a methacholine inhalation test before and after smoking a single cigarette. Ten of the subjects took part in a further study in which propranolol was inhaled before the smoking challenge to diminish the baseline beta adrenergic tone of the airway. After they had smoked a single filtered or non-filtered cigarette the indices of bronchial responsiveness (the cumulative dose of methacholine starting a decrease in the reciprocal of resistance, Grs (Dmin), and the cumulative dose causing a 35% drop in the Grs (PD35Grs)) did not change significantly. With the inhalation of propranolol mean (SD) log Dmin decreased from 1.37 (0.44) units to 0.74 (0.57) (p less than 0.01) and log PD35Grs from 1.93 (0.38) to 1.51 (0.38) (p less than 0.01). Smoking a single cigarette after the inhalation of propranolol did not, however, cause any further change in bronchial responsiveness. This study suggests that smoking a single filtered or non-filtered cigarette does not change bronchial responsiveness in non-smokers, and that changes in beta adrenergic tone of the airway do not modify the effect of smoking a single cigarette on bronchial responsiveness.

Superior protective effects of phenytoin against hypoxia in a pharmacological screening test

The selection of drugs to prevent the development of pathology in cerebral infarction remains an important problem. For the selection of effective drugs from among a large number of possible candidates, widely-used test screening techniques are sufficient for obtaining a good understanding of candidate drug effects. The effects of various drugs on the survival time of mice made hypoxic by exposure to a 4% O2-96% N2 gas have been examined. The survival time of 110 control animals was 170 +/- 6 s, showing a nearly normal distribution pattern. No control mouse had a survival time beyond 8 min. The survival time after the drugs were administered was as follows: suloctidil (12.5 mg/kg, n = 11), 1833 +/- 487 s; vitamin E (200 mg/kg, n = 15), 1160 +/- 342 s; pentobarbital (50 mg/kg, n = 12), 602 +/- 74 s; and phenytoin (100 mg/kg, n = 10), 2667 +/- 452 s. In contrast, administration of vitamin C, coenzyme Q, cytochrome c, beta-methasone, mannitol or germanium-132 did not result in prolongation of survival time. Comparison of the percentage of animals in each group which survived for more than 1 h showed 0% in the control group, 45.5% in the suloctidil group (12.5 mg/kg), 23.5% in the vitamin E group (200 mg/kg), 0% in the pentobarbital group (50 mg/kg) and 70% in the phenytoin group (100 mg/kg). These findings suggest that phenytoin is the most effective drug in combatting the effects of hypoxia (survival time was expressed as mean +/- SE).

[Persistent primitive first cervical intersegmental artery (proatlantal artery II) with occlusion of the basilar artery--a case report]

A rare case of persistent primitive first cervical intersegmental artery (proatlantal artery II) is reported. A 58-year-old man was admitted to our hospital with dysarthria and left hemiparesis. On admission he was stuporous with bilateral gaze palsy and left hemiparesis. CT scan on admission showed low density areas in the right cerebellar hemisphere and ventricular part of the pons. Right retrograde brachiography revealed occlusion of the basilar artery, aplasia of the right vertebral artery and an abnormal vessel connecting the right external carotid artery and the right vertebral artery. This anastomotic vessel was thought to be a persistent primitive first cervical intersegmental artery (Proatlantal artery II). Left carotid angiography revealed the left posterior cerebral artery was visualized through the posterior communicating artery, leading from the internal carotid artery. Left retrograde brachial angiography showed that the left vertebral artery terminated just distal from the branching of the left posterior inferior cerebellar artery. After admission the left hemiparesis deteriorated gradually and tracheotomy was done due to respiratory difficulties. The patient was then transferred to the rehabilitation center on his 34th day in hospital with neurological deficits.

Intracerebral hemorrhage from a metastatic brain tumor. Importance of differential diagnosis preceding stereotaxic hematoma aspiration

Three cases of sudden intracerebral hemorrhage, which were diagnosed as hemorrhage from metastatic brain tumors following stereotaxic aspiration of a hematoma, are reported. Two cases had subcortical hemorrhage and one had cerebellar hemorrhage. Neither contrast-enhanced computed tomography scans nor angiograms revealed any findings other than those indicating the hematoma in all three cases. However, retrospective study of the anamnesis showed very mild symptoms due to metastasis to the brain or spinal cord in one case each. In cases of intracerebral hematoma located at atypical sites, extreme care is required for the differential diagnosis.

[A successful removal of huge confluence meningioma]

A rare case of huge confluence meningioma with many kinds of venous collaterals is presented. A 58-year-old female was admitted because of severe headache and gait disturbance. An enhanced CT (computerized tomography) scan demonstrated a homogeneous spherical high density mass in the region of the posterior falco-tentorial junction adjacent to the internal occipital crest. Cerebral angiograms showed (1) the occluded confluence sinuum and compensatory venous collaterals, (2) venous drainage through the persistent falcial sinus, which was rare in an adult, from the straight sinus into the superior sagittal sinus (SSS), (3) venous drainage through diploic veins and emissary veins into scalp veins. The tumor including the confluence sinuum was totally removed via a combined bioccipital and suboccipital craniectomy. The confluence sinuum was invaded and occluded by the tumor. The tumor was histologically diagnosed as a fibroblastic meningioma. Post-operative angiogram showed a formation of the new venous channel which is located between the posterior part of the SSS and the lateral part of right transverse sinus. The origin of this new venous pathway was thought to be congenital presence of a "latent" dural venous channel. After ventriculoperitoneal shunting, the patient was discharged without any neurological deficits. A follow-up angiogram one year and two months after discharge showed that the channel become dilated and the venous collaterals seen before surgery disappeared probably due to the change of balance of venous pressure. The venous drainage pattern seemed to become resembling the normal variant type in which the SSS drains into the right transverse sinus, and left sinus was hypoplastic.(ABSTRACT TRUNCATED AT 250 WORDS)

[CT-guided stereotaxic biopsy in 104 cases of brain tumor]

Biopsy of suspected brain tumor was performed on 104 cases using Leksell's CT-guided stereotaxic system. The entire operation was performed in the CT room. A Backlund's spiral biopsy needle was advanced to the target point in a stepwise fashion and two to nine tissue samples were obtained from one to three biopsy tracks. Tissue sampling was impossible in two cases because the tumors were too hard for biopsy needle to advance. Also, sampling was sometimes difficult in the case of soft and necrotic tumor, cystic tumor, already treated (irradiated) tumor and the lesion including old blood clot. After the biopsy, minimal bleeding occurred in nine cases, however, stopped within 10 minutes by controlling the blood pressure. A minimum sized hematoma was visible on the postoperative CT in four cases. Postoperative neurological deterioration was seen in two cases. One case was transient and the other seemed to be in his natural course. Anyway, there were neither cases of operative mortality nor severely complicated cases in these series. Useful pathological diagnosis was possible in 83 cases (80%). Accurate diagnosis was not possible in the remaining 21 cases, however, their histological datum such as necrosis, blood clot, and so on were very useful to estimate the lesions. In summary, accurate diagnosis rate of CT-guided stereotaxic needle biopsy was 80%. However, it appeared to be a safe and useful procedure in the diagnosis of intracranial mass lesions.