Optically Induced Nuclear Spin Polarization in the Quantum Hall Regime: The Effect of Electron Spin Polarization through Exciton and Trion Excitations.

We study nuclear spin polarization in the quantum Hall regime through the optically pumped electron spin polarization in the lowest Landau level. The nuclear spin polarization is measured as a nuclear magnetic field B(N) by means of the sensitive resistive detection. We find the dependence of B(N) on the filling factor nonmonotonic. The comprehensive measurements of B(N) with the help of the circularly polarized photoluminescence measurements indicate the participation of the photoexcited complexes, i.e., the exciton and trion (charged exciton), in nuclear spin polarization. On the basis of a novel estimation method of the equilibrium electron spin polarization, we analyze the experimental data and conclude that the filling factor dependence of B(N) is understood by the effect of electron spin polarization through excitons and trions.

Recombinant human basic fibroblast growth factor accelerates fracture healing by enhancing callus remodeling in experimental dog tibial fracture.

Effect of recombinant human basic fibroblast growth factor (bFGF) on fracture healing was investigated using a tibial fracture in beagle dogs. Transverse fractures in the middle of the diaphyses were created in the right tibiae and bFGF was injected into the fracture sites at a single dose of 200 micrograms. The time course of changes in callus volume and morphology of the fracture sites were evaluated at weeks 2, 4, 8, 16, and 32 after treatment, and the fracture strength was analyzed at weeks 16 and 32. At week 2, a radiogram of the fracture site showed obvious membranous ossification in the group injected with bFGF. Basic FGF extended the callus area at week 4 and increased the bone mineral content (BMC) in the callus at week 8. bFGF also increased the osteoclast number in the periosteal callus at weeks 2 and 4. In the bFGF group, a maximal increase in the osteoclast index was found at week 4, and an identical increase was recognized in the control group at weeks 8 and 16. These findings strongly suggested that bFGF stimulated not only callus formation but osteoclastic callus resorption. BMC in the bFGF group was followed by a rapid decrease from week 8, while that in the control group was identical from week 4. Fracture strength of the bFGF group showed significant recovery by week 16, and recovery was still evident by week 32. We conclude that bFGF promotes the fracture healing in dogs by the stimulation of bone remodeling.

Giant aneurysm at the origin of the accessory middle cerebral artery.

BACKGROUND: Aneurysms of the A1 portion of the anterior cerebral artery are rare. The accessory middle cerebral artery is also a rare anomalous artery. CASE REPORT: We operated on a 53-year-old man because of a giant aneurysm which arose at the junction of the accessory middle cerebral artery and the horizontal portion of the anterior cerebral artery (A1 portion). CONCLUSION: This is the first report of a giant aneurysm of that region. A detailed evaluation of the angiogram is necessary prior to the operation, in order to select the most appropriate operative method to secure the blood flow of the accessory middle cerebral artery and distal anterior cerebral artery.

Spontaneous regression of primary malignant intracranial lymphoma.

A rare case of intracranial multiple tumor, which disappeared spontaneously on serial cranial computed tomography (CT) scans, is described. The initial CT scan showed multiple, well-enhanced lesions in the right frontal and parietal lobes. The lesions disappeared spontaneously without any treatment during the 2 following months of observation. One month later, however, a newly formed tumor was found on serial CT-scanning. Surgical intervention confirmed the histologic diagnosis of a non-Hodgkin's, large, and diffuse-type malignant lymphoma. The possible mechanism of temporal disappearance of tumors on CT scanning is discussed.

Brain functions of an infant with hydranencephaly revealed by auditory evoked potentials.

Hydranencephaly is a severe condition of brain characterized by the almost complete absence of the cerebral hemispheres with the thalamus, cerebellum and brainstem being preserved. This paper reports hydranencephaly in a 3-month-old boy. Cranial magnetic resonance imaging (MRI) revealed the condition and an auditory evoked potential study which was performed in order to investigate residual brain function. They showed normal auditory brainstem function but no appearance of other auditory evoked potentials originating from the higher brain.

Diffuse axonal injury associated with multiple traumatic aneurysms of the distal anterior cerebral artery--case report.

A rare case of multiple traumatic aneurysms, arising from the distal anterior cerebral artery (ACA), associated with a diffuse axonal injury is presented. An 18-year-old male sustained a frontal impact injury in a traffic accident on February 19, 1988. He immediately lost consciousness and was transported to a local hospital where his Glasgow Coma Scale score was 6. A computed tomographic scan showed a traumatic subarachnoid hemorrhage extending from the corpus callosum to the left parietal lobe. With conservative treatment, he gradually regained consciousness and was referred to our hospital 12 days later. Skull x-rays revealed no fracture. A right common carotid angiogram revealed multiple aneurysmal dilatations on the right distal ACA. A left frontoparietal craniotomy was then performed to determine the nature of the aneurysmal dilatation, and to evacuate the intracerebral hematoma because his right hemiparesis persisted. Two aneurysmal dilatations on the distal ACA were tightly surrounded by clots and a hematoma extended from the corpus callosum to the parietal lobe. The ACA was trapped proximal and distal to the aneurysmal dilatations. The postoperative course was uneventful.

The cystic growth of a subependymal giant-cell astrocytoma with tuberous sclerosis.

A case of a 7 year-old boy with subependymal giant-cell astrocytoma is reported. CT scanning of this patient for 6 years showed the cystic growth of the astrocytoma. The surgical indication and importance of periodic CT studies for subependymal giant-cell astrocytomas associated with tuberous sclerosis are discussed.

Transient global amnesia and dural arteriovenous fistula of the anterior cranial fossa.

Dural arteriovenous fistula (AVF) of the anterior cranial fossa is associated usually with cerebral hemorrhage or subarachnoid hemorrhage, while an association with transient global amnesia has not been reported previously. A case presenting the latter unusual symptom is described and the surgical treatment of AVF is discussed. A 64-year-old woman was hospitalized complaining of transient memory impairment. Magnetic resonance (MR) imaging demonstrated a flow void in the left frontal lobe and temporal pole. Cerebral angiography revealed an AVF in the anterior cranial fossa, which was fed bilaterally by the ethmoidal arteries and by branches of the external carotid arteries. The AVF drained into the superior sagittal sinus and the superficial sylvian vein via large varices. Following transfemoral embolization, surgical treatment was carried out. Postoperative angiography revealed complete obliteration of the anomaly. There were no further episodes of amnesia. In our presented case, there is an association between the presenting symptoms and the AVF. The combination of ischemia and congestion in the frontal and temporal lobes may have caused transient memory impairment. From our surgical experience, the excision of the vascular connection between the dura and the frontal lobe following the coagulation of the dura mater of the anterior part of the base of the skull without extensive excision seems to be recommended.

Clinicopathological features of intraorbital neurinoma--report of two cases.

Clinicopathological features of intraorbital neurinomas were investigated in two patients. Magnetic resonance imaging (MRI) findings in Case 1 were similar to those in Case 2. The central region of the neurinomas showed a slightly high intensity area with a marginal low intensity on T1-weighted images (T1WI), whereas on T2-weighted images (T2WI), the central area of the tumor was very low intensity with a marginal high intensity area. After gadolinium-DTPA (Gd-DTPA) injection, these areas were homogeneously enhanced in both cases. The deference in enhancement after Gd-DTPA injection reflected the distribution of cellularity and vessels in the tumor.

[Screening test of crude drug extract on anti-HIV activity].

The anti-HIV-1 effects of 204 crude drugs of common use in Japan were evaluated in vitro. As a result, 45 samples inhibited HIV-1-induced cytopathogenicity in MT-4 cells. In particular, the hot water extracts of Lithospermum erythrorhizon (root) and Prunella vulgaris (spike) showed the strongest anti-HIV-1 activities. Their IC100 values were both 16 micrograms/ml. In general, the hot water extracts of the crude drug suppressed the replication of HIV-1 growth more strongly than the cold water extracts.

[Correlation of the grade of nuclear and cortical cataract, visual acuity, and contrast sensitivity].

A correlative investigation of 125 eyes with senile cataractous lenses was conducted to determine the relationships between cortical (CC) and nuclear cataracts (NC), corrected visual acuity (VA), and contrast sensitivity (CS). The CS for the spatial frequency of 1.5 cycles/degree (c/d) and 12.0 c/d was analyzed in particular detail. The results were as follows: (1) CC and CS for both 1.5 and 12.0 c/d showed statistically significant negative correlations with a coefficient (CE) of -0.250 and -0.288 respectively. No correlation was found between CC and VA. (2) NC and VA showed a significant negative correlation with CE of -2.29. No correlation was found between NC and CS for at 1.5 and 12.0 c/d. (3) VA and CS showed a significant positive correlation with a CE of +0.436 at 1.5 c/d and +0.270 at 12.0 c/d. The CS at 1.5 and the CS at 12.0 c/d also showed a significant negative correlation with a CE of +0.477. (4) NC and CC showed a significantly negative correlation (r = -0.224, p < 0.01), suggesting that scattered light from the nucleus may be interfered with by cortical opacities during slitlamp examinations. (5) In 29 cases of no cortical opacity, nuclear opacity showed significant negative correlation with VA (r = 0.556 p < 0.01) but no significant correlation with CS of both 1.5 and 12 c/d. (6) In 30 cases with less than 0.085 of nuclear opacity, cortical opacity showed significant negative correlation with CS at 12.0 c/d (r = 0.364 p < 0.01) but showed no significant correlation with VA and CS at 1.5 c/d.

[Spinal injury in children].

We reported five cases of children with spinal injuries. Spinal injuries are rare in children, and most common from the occiput to C3 in children younger than 8 years. In our cases, two younger children had upper cervical lesions and two older children had lower lesions. These differences result from anatomical characteristics, such as special histological architecture of the growth zones in younger children. One patient had a delayed onset paraplegia without radiographic abnormality. This phenomenon seems to be one of the characteristics of the spinal injuries in children. Because of this, all children with head or neck injuries should be fully investigated. A nine-month-old child who suffered from a fracture of the odontoid process with atlantoaxial dislocation was treated by immobilization only, and the result was good. Generally, fracture of the odontoid process in young children can be treated by proper immobilization. One patient with fracture dislocation of the cervical spine died as a result of cord injury. So immediate surgical decompression is mandatory for patients with evidence of cord compression.

[Significance of multimodality evoked potentials (MEPs) in severe head injuries].

Clinical significance of multimodality evoked potentials (MEPs) consisting of auditory evoked brainstem response (ABR), cortical somatosensory evoked potential (SEP) and visual evoked potential (VEP) was studied in 14 cases with severe head injuries. The cases in this series associated with cerebral contusion and/or intracranial mass lesions such as acute subdural, intracerebral and acute epidural hematomas and Glasgow Coma Scale (GCS) score was less than 8 in all instances. MEPs were recorded for 14 days after injury and evaluated by MEP grade modified from Greenberg, et al. Intracranial pressure (ICP) was monitored from the extradural space on main lesion side in all cases for 3 to 5 days. Transtentorial herniation on CT scan was also graded according to the status of subarachnoid cisterns around the tentorium. The outcome was assessed by Glasgow Outcome Scale at 3 months after injury and was classified into good, poor and dead. MEPs on admission showed mild to severe abnormalities determined by single or all modalities in all cases and they were fairly well correlated with GCS score on admission and initial ICP. In the cases with good outcome, initial MEPs showed mild to moderate abnormalities determined by single modality and improved within 3 days after injury. They returned to normal or remained at mild abnormality at 7 days. But abnormality on initial MEPs was more severe in the cases with poor outcome and they were deteriorated within 3 to 7 days when elevation of ICP above 25 mmHg was observed. MEPs remained at moderate abnormality even at 14 days after injury in these cases.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of convexity arachnoid cyst associated with chronic subdural hematoma and intracystic hemorrhage].

Arachnoid cysts account for about 1% of all intracranial tumors, in which about 50% arise from the middle cranial fossa, and rarely occur at the cerebral convexity. They sometimes are associated with chronic subdural hematoma (CSDH) but the exact mechanism of their development is still unclear. A 15-year-old boy was admitted to our hospital with an arachnoid cyst at the right frontal convexity. When he experienced recurrent generalized seizure, CT and MRI revealed CSDH localized at the surface of the arachnoid cyst. Radical operation for the cyst with CSDH was successfully performed. As far as we know, it is rare that CSDH and hematoma are colocalized over an arachnoid cyst at the cerebral convexity. In this report, the operative findings of this patient and possible mechanism of CSDH formation were reported.

[Treatment of acute subdural hematoma with low GCS score].

In order to clarify the present problems in the treatment of acute subdural hematoma with low GCS score (5 or less), we studied the difference of the outcomes from two different surgical treatments for these patients. The present series included 30 patients who had GCS scores of 3, 4 or 5, and they were divided into two groups: 16 in DH group who had decompressive hemicraniectomy and 14 in HITT group who had hematoma irrigation with trephination therapy. The mean age of the patients was 47 years. They all had an intensive medical management including barbiturate therapy under intracranial pressure (ICP) monitoring after the operation. Time course of ICP after operation was classified as controlled, high but reduced and uncontrollable, based on the ICP level of 30 mmHg. The outcomes of the patients were determined by use of Glasgow outcome scale and classified into good, poor and dead. In these patients, the outcome was good in 13.3%, poor in 23.3% and dead in 63.4%. There was no survived case in those with GCS score of 3. The mortality rate in older patients over 60 years was high as 81.8%. ICP was well controlled in 2 patients (12.4%) in DH group. But there is no such case in HITT group. Uncontrollable ICP was more frequently seen in HITT group than in DH group. The patients showed different outcomes in the two types of treatment. Good outcome was found in 18.7% and the mortality rate was 56.3% in DH group. On the other hand, only one patient (7.1%) showed good outcome and the mortality rate of 71.4% in HITT group.(ABSTRACT TRUNCATED AT 250 WORDS)

[Efficacy and limitation of postoperative barbiturate therapy in severe head injury].

Efficacy and limitation of barbiturate therapy employed as postoperative treatment for acute traumatic intracranial hematomas were studied in 20 patients. The clinical cases in this series included 15 males and 5 females with mean age of 41.8 years who all were operated on for intracranial hematomas within 3 days after injury. Glasgow Coma Scale (GCS) score was less than 7 in all instances and intracranial pressure (ICP) as well as arterial pressure was monitored postoperatively with Gaeltec and Gould transducers. Barbiturate therapy (5 mg/kg of thiopental as an initial dose and loading dose of 2-3 mg/kg/hour) was given when ICP rose above 20 mmHg and maintained for 3 days after operation. The outcome of the patients was assessed by Glasgow Outcome Scale 3 months after injury. The response of barbiturate on ICP and the changes of cerebral perfusion pressure (CPP) during the therapy in relation to the outcome were studied. Final outcome of the patients revealed 5 of good (good recovery and moderate disability), 3 of poor (severe disability and vegetative state) outcomes and 60% of mortality rate. Eleven out of 20 patients responded to barbiturate therapy and 0-20 mmHg of ICP reduction (mean reduction of 10 mmHg) was obtained in these cases. Among these cases, 2 out of 3 dead patients were older than 60 years. There were no responses of barbiturate in 7 patients to whom the therapy was started when ICP rose above 40 mmHg. No response of the therapy on ICP was also observed in the patients with GCS score of 3.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of intraosseous meningioma].

A case of intraosseous meningioma at the posterior fossa was reported. Intraosseous meningioma is very rate and only six cases have been reported in Japanese literature. A 64 year-old woman complained of progressive headache and was admitted to Ichinomiya Neurosurgical Hospital. On admission, neurological examination did not reveal any abnormalities. However, plain skull X-p showed a hyperostotic lesion in the right posterior fossa. CT scan demonstrated homogeneously enhanced mass by contrast medium. MRI showed a mass lesion of the posterior fossa on T1 and T2 weighted images. The right vertebral angiogram showed an avascular area in the right posterior fossa and no tumor stain. The tumor, which was partially attached to the underlying dura, was successfully removed surgically. The operative finding confirmed an intraosseous meningioma which had arisen from the right asterion. The post operative course was uneventful. Histological examination revealed fibroblastic meningioma.

[Entirely suprasellar symptomatic Rathke's cleft cyst].

Two rare cases of entirely suprasellar Rathke's cleft cyst were reported. Case 1. A 62-year-old man was admitted to our hospital on the 14th of January, 1988, complaining of headache and diplopia. A plain skull x-ray showed the sella turcica was normal. CT scan and MRI demonstrated a lesion mass located entirely in the suprasellar cistern. Right frontotemporal craniotomy was performed, and the cyst wall was resected subtotally. Microscopic sections of cyst wall showed ciliated single layer with focal stratified epithelium. Case 2. A 51-year-old man was hospitalized complaining of visual impairment in the left eye. Endocrinological examination showed no abnormalities. CT and MRI demonstrated a lesion mass located entirely in the suprasellar region. Right frontotemporal craniotomy was performed. The mass was opened and a large amount of yellowish fluid was released. Histologically, the specimens were simple ciliated cuboidal epithelium. Postoperative courses of these patients were uneventful. The findings on CT and MRI of the cases located entirely in the suprasellar region were varied. The histopathogenesis and embryological pathogenesis of Rathke's cleft cyst in the literature, particularly the entirely suprasellar type, were discussed.

[3 operated cases of congenital deficiency of Factor XIII associated with intracranial hematomas].

Three operated cases of congenital deficiency of factor XIII (fibrin-stabilizing factor) associated with intracranial hematomas were described and the diagnosis, replacement therapy of the factor were discussed. Congenital deficiency of factor XIII is quite rare coagulation disorder and only 100 patients were reported in the literatures in which we could find only one case who had craniotomy for associated intracranial hemorrhage. Case 1: A 41-year-old female with the history of unknown hemorrhagic diathesis complained of headache and right hemiparesis on August 2, 1980. CT scan showed left parietal intracerebral hematoma caused by unknown hemorrhagic diathesis and operated on under fresh blood transfusion. Postoperative state was uneventful but bleeding from the operated wound and rebleeding in the operated hematoma cavity were found on 5th postoperative day. The screening test for factor XIII was abnormal but replacement therapy with fresh plasma and factor XIII failed to control hemorrhagic diathesis. The patients died of GI bleeding and recurrent intracerebral hematoma on 21st postoperative day. Case 2: A 1.4-year-old boy with the history of umbilical bleeding on delivery and diagnosed as congenital deficiency of factor XIII in the other hospital fall down and struck his occiput on September 20, 1980. He vomited and became stuporous two days after injury, and was transferred to Ryukyu University Hospital. CT can revealed epidural hematoma at the left posterior fossa which extended to the supratentorium. The hematoma was successfully evacuated under infusion of fresh plasma and he showed uneventful recovery without rebleeding by postoperative appropriate replacement therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

[Noninvasive evaluation of hemispheric cerebral circulation and brain function in acute intracranial hypertension].

Disturbance of the hemispheric cerebral circulation and brain dysfunction in acute intracranial hypertension were evaluated noninvasively by ultrasonic Doppler technique and multimodality evoked potentials consisting of auditory evoked brain-stem response (ABR), cortical somatosensory evoked potential (SEP) and visual evoked potential (VEP) in 36 patients with severe head injury and cerebrovascular disease. Glasgow coma scale score was less than 8 in all cases and the age ranged from 17 to 75 years (mean of 46 years). Intracranial pressure (ICP) was measured from the extradural space using Gaeltec transducer and systemic blood pressure was simultaneously recorded. Common carotid blood flow velocity (CBFV) was recorded on both sides and mean velocity (M), diastolic mean velocity (Md) and mean blood flow were calculated. The abnormalities on MEPs were graded into 4 categories. M and Md values on CBFV were significantly (p less than 0.05 and p less than 0.01) lowered on affected side (main lesion side) even when ICP was staying less than 20 mmHg comparing with control value obtained from the normal subjects (M: 19.48 +/- 3.52, Md: 15.98 +/- 2.01 cm/sec). With the increase of ICP more than 21 mmHg, CBFV on the contralateral side was also decreased and M as well as Md values were maintained at the lowered level during 21 to 60 mmHg of ICP. A significant rapid decrease of CBFV was observed at extreme intracranial hypertension more than 61 mmHg. Lowered CBFV was also noted when cerebral perfusion pressure was reduced less than 50 mmHg.(ABSTRACT TRUNCATED AT 250 WORDS)