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In this experiment, we examined a possible protective effect of encapsulated neurotrophic factor-secreting cell grafting for ischemic injury. We established a basic fibroblast growth factor (bFGF)-secreting cell line by genetic manipulation. We enveloped these cells into polymer capsules, which consist of a semipermeable membrane, and implanted them into the right striatum of rats. At 6 days after implantation, these rats received right middle cerebral artery occlusion (MCAO) using interluminal suture technique. At 24 h after MCAO, rats were sacrificed and their cerebral infarction volume was determined by 2,3,5-triphenyltetrazolium chloride (TTC) staining and image analysis. We found approximately 30% reduction in infarct volume in the encapsulated bFGF-secreting cell grafting groups vs. the encapsulated naive BHK cell grafting group or the without implantation group. We measured bFGF secretion from encapsulated bFGF-secreting cells using enzyme-linked immunosorbent assay (ELISA). The retrieved capsules continued to secrete bFGF. There was no significant difference of bFGF secretion between the capsules before and after transplantation. A large number of viable BHK-bFGF cells was observed within the full length of the retrieved capsule. These results indicate that encapsulated bFGF-secreting cell grafting exerts a protective effect on ischemic injury.

Intradural pseudoaneurysms arose in two patients as a result of arterial injury incurred during surgery. In the first patient, the pseudoaneurysm developed in the middle cerebral artery, at the site of vessel perforation during aneurysmal surgery. In the second patient, the pseudoaneurysm developed in the anterior communicating artery after removal of a tuberculum sellae meningioma. These aneurysms had small ostia and were successfully embolized with electrolytically detachable coils. The clinical features and the treatment of intracranial pseudoaneurysms are discussed.

Glial cell line-derived neurotrophic factor (GDNF) is a member of the transforming growth factor beta superfamily and acts as a neurotrophic factor for the nigrostriatal dopaminergic system. GDNF at a dose of 100 micrograms was injected stereotactically into the striatum of Sprague-Dawley rats that had been treated with intrastriatal 6-hydroxydopamine (6-OHDA) injection four weeks earlier. Immunocytochemical and behavioral analyses showed significant recovery of the nigrostriatal dopaminergic system after a single GDNF injection or continuous GDNF injection. Immunocytochemical and behavioral study showed that there was no significant difference between the results obtained from the two different injection methods. This result demonstrates the potential usefulness of GDNF for the treatment of Parkinson's disease.

Stereotactic surgery and neuronal transplantation are considered to be effective surgical therapies for advanced Parkinson's disease with wearing off phenomenon. As a stereotactic surgery, posteroventral pallidotomy and chronic pallidal or subthalamic stimulation with inhibitory parameters were performed. Flattening of the motor fluctuations were obtained with improving general motor symptoms especially at "off" time. Therapeutic l-dopa dose could not reduced following pallidotomy and pallidal stimulation, whereas subthalamic stimulation saved 30-50% of l-dopa dose. By the constant supply of dopamine, neuronal transplantation was effective on wearing off. Chromaffin cells of adrenal medulla and pretransected peripheral nerve were cografted into the bilateral caudate nuclei. After the transplantation significant reduction of % time off and l-dopa dose was observed.

The transplantation of encapsulated dopamine-secreting cells into the striatum represents one potential means of treating Parkinson's disease. The present study investigated the ability of encapsulated PC12 cells, which are derived from rat pheochromocytoma, to supply L-dopa and dopamine into the primate brain in the long term and to effect functional improvement in the animals. Following polymer encapsulation, PC12 cells were transplanted into the striatum of hemiparkinsonian monkeys. The secretion of L-dopa and dopamine from the encapsulated cells, the morphology of these cells, the histology of the host striatum surrounding the capsule, and functional changes in the host animals were examined 1, 6, and 12 months after transplantation. Analysis of retrieved capsules revealed that the PC12 cells survived and continued to release L-dopa and dopamine even 12 months after transplantation. The histological response of the host brain surrounding the capsules was minimal and there were no signs of immunological rejection or tumor formation. The physical condition of the host animals was good for 12 months, and hematologic and cerebrospinal fluid analysis revealed that no animals suffered from infection or immunological reaction. These PC12 cell-grafted monkeys showed improvements in hand movements after transplantation, effects that lasted for at least 12 months. These results further support the potential use of this approach for the treatment of Parkinson's disease.

Glial cell line-derived neurotrophic factor (GDNF) is a member of the transforming growth factor-beta superfamily and acts as a neurotrophic factor for the nigrostriatal dopamine (DA) system. Although previous studies have shown that pretreatment with GDNF could prevent degenerative changes of nigrostriatal DA system by DA neurotoxin 6-hydroxydopamine (6-OHDA), it is not really known whether GDNF can induce recovery of nigrostriatal DA system after partial lesioning by 6-OHDA. Substantia nigra has been commonly chosen as injection site for GDNF but a limited number of studies have used striatum as injection site where neural transplantation is commonly performed. Unilateral intrastriatal administration of 6-OHDA was performed in Sprague-Dawley rats to create partial lesion of the nigrostriatal DA system. These hemiparkinsonian model rats received a 10- or 100-microg single injection of human recombinant GDNF into the same portion of the striatum 4 weeks after 6-OHDA treatment. Both animals that received a 10- or 100-microg single injection of GDNF showed decreased apomorphine-induced rotation at 2 weeks after injection. More potent and prolonged functional recovery was observed in animals receiving 100 microg of GDNF than in those receiving 10 microg of GDNF. Tyrosine hydroxylase (TH) immunocytochemistry revealed that TH positive DA fiber density in the striatum and the number of DA cell bodies in the substantia nigra were greater in animals receiving 10 or 100 microg of GDNF than those receiving saline. These immunocytochemical results have also shown that 100 microg of GDNF was more potent than 10 microg of GDNF. These morphological and functional results indicate that GDNF treatment 4 weeks after 6-OHDA lesioning could induce recovery of nigrostriatal DA system. Striatum was a good site for GDNF administration for hemiparkinsonian rats and a single injection of 100 microg of GDNF was more potent than 10 microg of GDNF.

Purpose: Neurotrophic factor delivery into the brain is a promising approach in the treatment of Parkinson's disease. Glial cell line-derived neurotrophic factor (GDNF) is one of the most potent neurotrophic factors for dopaminergic neurons. Although multiple injections of GDNF into the brain are commonly performed in experimental studies, the present study investigates the efficacy of using a single injection of GDNF, which may be useful in elinically applying this treatment., Methods: Unilateral 6-hydroxydoparnine (6-OHDA) administration into the striatum was perforrned in Sprague-Dawley rats to create a partial lesion of the nigrostriatal DA system. These parkinsonian model rats received a single injection of human recombinant GDNF into the same portion of the striatum either 24 h before or 4 weeks after 6-OHDA treatrnent., Results: GDNF injected into the striatum before 6-OHDA administration potently protected the dopaminergic system, as shown by the numbers of mesencephalic dopaminergie neuron cell bodies and dopaminergic nerve terminal densities in the striatum. Dopaminergic neuron cell bodies and fiber densities were also significantly restored when GDNF was given after 6-OHDA administration, although the degree of restoration was lower than in the protective experiment. ODNF administration ameliorated apomorphine-induced rotational behavior in animals receiving it either before or after 6-OHDA treatment. However, the degree of improvement was less prominent when GDNF was iniected after 6-OHDA., Conclusion: Intracerebral GDNF adininistration exerts both protective and regenerative effects on the nigrostriatal dopaminergic system, a finding which may have implications for the development of new treatment strategies for Parkinson's disease.

Background: Glial cell line-derived neurotrophic factor (GDNF) has been shown to be a survival and neuroprotective factor for nigrostriatal dopaminergic neurons in vivo. The present study was designed to investigate the possible neuroprotective and restorative role by GDNF for dopaminergic neurons which were exposed to the neurotoxin 6-hydroxydopamine (6-OHDA)., Method: We compared neurochemical, morphological and behavioural changes following striatal infusion of GDNF to those following intracerebroventricular (i.c.v.) infusion., Findings: Apomorphine-induced rotation showed significant recovery after both types of infusion. Significant recovery of tyrosine hydroxylase (TH)-immunoreactive (IR) neurons and fibers were found in the substantia nigra and striatum following both striatum and i.c.v. infusion except for the number of TH-IR neurons in the i.c.v. infusion group., Interpretation: These results suggest that GDNF induces recovery of the nigrostriatal dopaminergic system, and this indicates a potential usefulness of GDNF for the treatment of Parkinson's disease.

Intrastriatal implantation of polymer-encapsulated PC12 cells, which constitute a dopaminergic cell line derived from rat pheochromocytoma, has proved useful for ameliorating parkinsonian symptoms in several kinds of animals. In considering the clinical application of this technique, we should make sure that PC12 cells are rejected completely by the host immune system in case the capsule breaks. In the present study, unencapsulated PC12 cells were injected into the brain of Japanese monkeys (Macaca fuscata). Histological [hematoxylin-eosin (H&E), Nissl] and immunocytochemical [tyrosine hydroxylase (TH), and glial fibrillary acidic protein (GFAP)] analyses were performed 1, 2, 4, and 8 weeks after transplantation. Also, encapsulated PC12 cells were transplanted into the brain of another group of Japanese monkeys to investigate the host reaction to the capsule and to confirm that the encapsulated PC12 cells continue to survive in the host brain. H&E and GFAP staining were performed 2, 4, and 8 weeks after transplantation. L-DOPA and dopamine release from the explanted capsules was measured by high performance liquid chromatography. Magnetic resonance imaging was performed in both unencapsulated and encapsulated PC12 cell grafted groups. Although the xenografted unencapsulated cells formed a small cluster at 1 and 2 weeks after implantation, very few and no viable PC12 cells remained at 4 and 8 weeks, respectively. The reaction of the host towards the xenograft gradually decreased. Encapsulated PC12 cells retrieved from the host brain were found to release L-DOPA and dopamine continuously even 8 weeks after implantation. The host reaction to the PC12-loaded capsule was much weaker than that to the unencapsulated PC12 cells, and decreased with time. These results indicate that encapsulated PC12 cell transplantation is an effective and safe strategy for the treatment of Parkinson's disease.

1. Neural transplantation is one promising approach for the treatment of Parkinson's disease. Fetal substantia nigra cells are a good source of dopamine, but in order to avoid ethical and immunological problems, adrenal medullary chromaffin cells have been investigated as an alternative source. 2. Grafted adrenal medullary chromaffin cells can provide dopamine as well as several neurotrophic factors that affect dopaminergic neurons in the brain. 3. We review experimental studies for application of neural transplantation techniques in Parkinson's disease, including immunological studies, cryopreservation, microvasculature, donor tissue, and direct gene delivery studies performed in our laboratory. Our clinical experience and new approach involving a polymer-encapsulated cell grafting procedure are also described.

Cerebral aneurysms causing visual symptoms before surgery are relatively rare. We have experience with 17 cases of such aneurysms and report their clinical features and surgical outcome. The locations of aneurysms presenting with visual dysfunction in our series are as follows: internal carotid (IC)-cavernous aneurysms in six of 29 total cases, 21%; IC-ophthalmic aneurysms in nine of 36 total cases, 25%; and anterior communicating artery (A com A) aneurysms in two of 217 total cases, 1%. The size of the aneurysms, the period between the onset of symptoms and surgical treatment, the pre- and post-operative visual function, and the surgical methods used to treat the aneurysm were analyzed. All the visually symptomatic cases featured large (15-24 mm) or giant (> 25 mm) aneurysms. Visual symptoms occurred before aneurysmal rupture in all cases but one. The type of visual field defect and the degree of reduced visual acuity were highly variable, without a typical clinical presentation. Five out of six IC-cavernous aneurysms were treated surgically with common carotid artery (CC) ligation or IC ligation with superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis. Three of these cases showed improvement of visual symptoms after surgery. Six out of nine IC-ophthalmic aneurysms were treated surgically (CC ligation or direct clipping), with four cases showing improvement of visual symptoms after surgery. One case of an A com A aneurysm featured a ruptured aneurysm that had physically penetrated the optic chiasm, while the other case was a giant unruptured aneurysm. The interval between the onset of symptoms and surgical treatment was the only factor identified which affected the clinical outcome of the aneurysms presenting with visual dysfunction. All cases that were determined to show improvement of visual function were treated surgically within 3 months of the onset of symptoms. Cerebral aneurysms presenting with visual dysfunction before surgery are most commonly large or giant, and unruptured. Recovery of visual function can most often be expected when surgical treatment is performed expeditiously, before the visual dysfunction becomes irreversible.

Objective: An extradural temporopolar approach has recently been used in the treatment of the parasellar, infrachiasmatic, or intracavernous regions. In this approach, the temporal (superficial) dural layer is separated from the deep layer (inner cavernous membrane) to expose the cavernous sinus extradurally. We report our experiences with 5 cases in which a giant pituitary adenoma invading the cavernous sinus and parasellar regions was resected via the extradural temporopolar approach., Patients and Methods: Between January 1995 and December 1997, 60 patients with pituitary adenomas were operated on at Okayama University Hospital. The extradural temporopolar approach was used for 5 patients who had a giant pituitary adenoma invading the cavernous sinus and parasellar regions. The 5 patients were women aged from 32 to 62 years and presented with a visual dysfunction. Four patients had hormonally non-functioning pituitary adenomas and one had a growth-hormone secreting pituitary adenoma., Results: The operations resulted in 1 total, 3 subtotal and 1 partial removal. There was no operative mortality or major morbidity. Transient oculomotor palsy occurred in 2 cases postoperatively. This approach provided excellent exposure of the tumor, relevant cranial nerves and arteries in and around the cavernous sinus through extradural retraction of the temporal lobe, allowing for sufficient resection of the intracavernous and parasellar portion of the tumor. Tumors invading the inferior portion of the clivus or the contralateral cavernous sinus could not be removed through this approach., Conclusion: Our findings suggest that the extradural temporopolar approach is useful for resection of giant pituitary adenomas invading the cavernous sinus and parasellar regions.

Glial cell line-derived neurotrophic factor (GDNF) is a member of the transforming growth factor beta superfamily and acts as a neurotrophic factor for the nigrostriatal dopaminergic system. GDNF was injected stereotaxically into the striatum of young (2 months old) and aged (12 months old) C57BL/6 mice that were treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) 1 week earlier. Immunocytochemical and neurochemical analyses showed significant recovery of the nigrostriatal dopaminergic system both in young and in aged mice. Since Parkinson's disease is a neurodegenerative disorder mainly affecting elderly people, this result demonstrates the potential usefulness of GDNF in treating Parkinson's disease.

As an alternative to virus-mediated gene transfer, we previously demonstrated a simple, safe, and efficient transfer of foreign gene into the central nervous system using continuous injection of a plasmid DNA-cationic liposome complex. To explore whether this approach can be applied to the treatment of certain neurological disorders, we used an experimental model of Parkinson's disease (PD) in the present study. Following continuous injection for 7 days, tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AADC) genes carried by a bovine papilloma virus-based plasmid vector were efficiently introduced into glial cells in the striatum of 6-hydroxydopamine-lesioned rats. Significant recovery in apomorphine-induced rotational behavior of PD models was obtained by transfection of TH gene and this effect continued for up to 5 weeks after injection. Moreover, cotransfection of TH with AADC genes was readily accomplished by this procedure and resulted in a greater and longer-lasting improvement of apomorphine-induced rotational behavior than was achieved by transfection of TH gene alone. We suggest that this approach is a controllable and manageable alternative to other methods of gene therapy for the treatment of PD.

Subarachnoid hemorrhage (SAH), encephalitis, meningitis, and autoimmune diseases sometimes lead to cerebral angiopathy, characterized specifically by narrowing of vessels, morphological changes in the structure of vessel walls, and a concomitant decrease in cerebral blood flow. Many patients also develop delayed ischemic neurological deficits. Thus, preventing vascular reactions is of paramount importance in treating SAH. Although cerebral vasospasm has some relationship with the inflammatory reaction of major cerebral vessels against the autologous blood, and many trials have attempted to prevent angiopathy after SAH, an effective treatment has not yet been established. The purpose of this article is to evaluate the preventive effect of nuclear factor KB (NF-kappaB) decoy oligo-DNA after SAH; since NF-kappaB is closely related to inflammation. In the rabbit angiopathy model after SAH, we evaluated the effectiveness of the decoy oligo-DNA using the angiographic (digital subtraction angiography) and histological (hematoxylin-eosin and Masson's trichrome staining) methods. Moreover, a gel-shift assay for NF-kappaB was also performed in order to evaluate the activity of NF-kappaB. We describe a new concept for treating cerebral angiopathy after SAH and for successfully inhibiting cerebral vasospasm and morphological changes in vessel walls in a rabbit model. In this treatment, we used synthetic double-strand oligo-DNA with a high affinity for transcription factor NF-kappaB, and cationic liposome complex administered through the cerebrospinal fluid.

Previously reported methods of liposome-mediated direct in vivo gene transfer have been inefficient, especially when performed with highly differentiated, quiescent cells of the adult mammalian central nervous system (CNS). We have therefore improved these procedures based upon a novel concept. Following continuous injection of plasmid DNA-cationic liposome complex which contained a reporter gene encoding E. coli beta-galactosidase into the striatum of adult rats, the expression of transgene was dramatically elevated without any adverse effects. This new technique may enable a wide application of liposome-mediated gene transfer technology not only to basic analysis of gene functions in the brain but also for clinical treatment of certain CNS disorders.

CSF rhinorrhea is a common complication of acoustic neurinoma surgery via the suboccipital route. In this paper we present our incidence of CSF rhinorrhea and our surgical techniques for reducing the risk of this post-surgical complication. Following removal of the acoustic neurinoma, the drilled posterior wall of the internal auditory canal is covered with bonewax, muscle or fat pieces, and fibrin-glue, while the previously reflected dura is sutured in place keeping the packing material in position. Bone chips removed during the craniectomy are then mixed with fibric glue and are used for a cranioplasty. Although we routinely perform aggressive drilling of internal auditory canal to facilitate total removal of the acoustic neurinoma, only 1 out of 94 consecutive cases (1%) showed postoperative CSF rhinorrhea. Since previous reports mention the rate of this complication following acoustic neurinoma surgery varies between 4% and 27%, we believe that our methods may be useful in helping reduce the incidence of postoperative rhinorrhea.

A case of unruptured bilateral large carotid-ophthalmic aneurysms, which appear to be adjoining and "kissing" each other when visualized by three-dimensional computed tomographic angiography (3-D CTA), is reported. Although bilateral carotid-ophthalmic aneurysms are not rare, bilateral large ones are quite rare, and direct imaging of "kissing aneurysms" of this portion has not been reported. Since 3-D CTA is becoming a useful tool for the diagnosis of cerebral aneurysms, we propose that these and similar bilateral large carotid-ophthalmic aneurysms are good candidates for the term "kissing aneurysms".

A number of approaches have been proposed for the treatment of intracavernous giant aneurysms. In the present study, we have analyzed long-term surgical outcome of 27 consecutive cases of our experience. All the cases were unruptured and symptomatic, showing symptoms such as extraocular movement disorder or visual disturbances. Thirteen cases were male and 14 cases were female. The age of the patients ranged between 11 and 75 years (average 52.2 years) and follow-up periods were between 1 and 20 years (average 7.7 years). Abducens nerve was distributed in 20 cases, oculomotor nerve in 12 cases, optic nerve in six cases, trigeminal nerve in six cases, and trochlear nerve in five cases. In addition to conventional angiography, three-dimensional computed tomographic angiography, balloon test occlusion (BTO), slow injection angiography, aneurysmography, and single photon emission computed tomography with BTO were used to determine a method of treatment. Therapeutic modalities of the present series were as follows: four cases were unoperated, common carotid artery ligation was performed in eight cases, internal carotid artery (IC) ligation in three cases, IC ligation plus superficial temporal artery (STA)--middle cerebral artery (MCA) anastomosis in four cases, IC ligation plus high flow vein bypass in three cases, IC trapping plus STA-MCA anastomosis in three cases, and direct clipping in two cases. Although two cases showed early and late ischemic complications, other cases demonstrated improvement of cranial nerve dysfunction relatively soon after surgical treatment and long-term outcome was generally good. It is concluded that good long-term surgical outcome is obtained for intracavernous giant aneurysms by selecting adequate surgical treatment based upon careful preoperative evaluation of these aneurysms using sophisticated diagnostic methods.

The PC12 phenochromocytoma tumor cell line is derived from a rat adrenal medullary tumor and secretes dopamine. We have previously reported that grafted microencapsulated PC12 cells using agarose and poly (styrene sulfonic acid) survived in the xenogeneic brain without immunosuppression. To investigate whether unencapsulated PC12 cells form a tumor and how they provoke immunological reaction, PC12 cell suspension was implanted into the striatum of Sprague-Dawley rat (allogeneic graft) or guinea pig (xenogeneic graft) and histological analysis using Nissl stain and immunocytochemical analysis using antityrosine hydroxylase (TH) antibody were performed 1, 2, and 4 wk after transplantation. Host animals were not immunosuppressed. PC12 cells formed a mass 1 and 2 wk after transplantation both in allogeneic and xenogeneic brain. These grafted PC12 cells were immunoreactive to anti-TH antibody. Four weeks after transplantation, however, grafted PC12 cells in the allogeneic brain were only found within the restricted area near the site of implantation. In the xenogeneic brain, only the trace of grafted PC12 cells were found around the site of implantation 4 wk after transplantation. In both allogeneic and xenogeneic animals, a number of lymphocytes were found in and around the grafts at all period investigated. These findings indicate that PC12 cells could survive in the allogeneic or xenogeneic brain for 2 wk and were ultimately rejected by immunological reaction by 4 wk after transplantation. Implantation of encapsulated PC12 cells in the allogeneic or xenogeneic brain is considered a safe and effective method for delivering dopamine into the brain because PC12 cells will not form a tumor in the long-term even if capsules are damaged in some reason.

The transplantation of genetically modified cells represents one potential means of delivering trophic factors to the brain to support the survival of host neurons and to increase the survival of co-grafted cells. The present study examined the ability of encapsulated baby hamster kidney (BHK) fibroblasts, which were genetically modified to produce human nerve growth factor (hNGF), to provide long-term trophic support to co-grafted adrenal chromaffin cells. Following polymer encapsulation, BHK-hNGF cells were grafted into the striatum of hemiparkinsonian rats together with unencapsulated adrenal medullary chromaffin cells. Secretion of hNGF from the encapsulated cells, morphology of these cells, apomorphine-induced rotational behavior of the host animals, and survival of the co-grafted chromaffin cells were examined 1, 6, and 12 months after transplantation. Analysis of retrieved capsules revealed that the BHK cells survived and continued to release hNGF at a level of 2-3 ng/day even 12 months after transplantation. Although the animals receiving adrenal medulla alone did not show recovery of apomorphine-induced rotational behavior, the animals receiving adrenal medulla intrastriatal hNGF-secreting cells showed a significant decrease (40-50%) in apomorphine-induced rotation within 1 month postimplantation that remained stable for the 12-month test period. Tyrosine hydroxylase immunocytochemistry further revealed that while survival of chromaffin cells without hNGF support was poor, co-grafting of adrenal medulla and BHK-hNGF cells dramatically 926- to 32-fold) increased chromaffin cell survival 1, 6, and 12 months after transplantation. These results demonstrate that (1) encapsulated BHK cells survive for extended periods of time in vivo while continuing to secrete hNGF, (2) the continued secretion of hNGF provides trophic support for co-grafted adrenal chromaffin cells, and (3) the increased chromaffin cell survival is associated with long-term, stable behavioral recovery. These data further support the potential use of this approach for treating Parkinson's disease.

Background and Purpose: Although mice, rats, and other small animals are commonly used for molecular biology research, their use in the evaluation of cerebral vasospasm after subarachnoid hemorrhage is somewhat problematic because of the correspondingly small size of their cerebral vessels. We have already reported that the corrosion cast technique was useful for evaluating newly formed cerebral vessels in neural grafts in these small animals. In the present study we applied the corrosion cast technique to the evaluation of hemolysate-induced cerebral vasospasm in rats and performed three-dimensional analysis for comparison. The casting was done 10 minutes after the hemolysate injection, so that only acute "vasospasm" was assessed., Methods: After withdrawal of 0.1 mL cerebrospinal fluid, 0.2 mL hemolysate (n = 9) or saline (n = 10) was injected into the cisterna magna of male Sprague-Dawley rats weighing between 300 and 350 g. Ten minutes later, perfusion of a semipolymerized casting medium was performed at an injection pressure of 100 to 120 mm Hg. The brains were immersed and corroded in 10% NaOH solution. After these procedures, the basilar artery as well as peripheral vessels was analyzed morphologically with scanning electron microscopy. Conventional histological analysis with the use of paraffin-embedded section with hematoxylin-eosin staining was also performed, and the results were compared with those for the corrosion cast methods., Results: In the saline-injected group, SEM showed that the inner surface of the basilar artery was smooth and the form of the endothelial cell was printed on the surface of the cast. In the hemolysate-injected group, the basilar artery showed an apparent vasospasm over its entire length, and corrugation was observed on the inner surface of the basilar artery in a three-dimensional fashion. Higher magnification revealed that the nuclei of the endothelial cells were distorted. Local narrowing of the basilar artery and vasospasm in the arteries of the anterior circulation and in peripheral arteries were also observed. Measurement of the inner diameter of the basilar artery showed 37.8% contraction in the hemolysate-injected group compared with the saline-injected group by the corrosion cast method. This degree of vasospasm was similar to that observed by the conventional histological method., Conclusions: In this report we show that detailed three-dimensional observation in the rat can be performed qualitatively and quantitatively with the corrosion cast technique. We conclude that this method derives an accurate measurement of the diameter of rat major cerebral arteries and is more reliable for analyzing vasospasm in rats than angiography and other conventional procedures.

There are few reports of anterior communicating artery aneurysms causing visual symptoms, and penetration of the optic chiasm by such aneurysms has not been reported. A 40-year-old man presented with the abrupt onset of left homonymous hemianopsia, right visual acuity disturbance (finger counting), and slight headache. Angiography disclosed a 7-mm anterior communicating artery aneurysm projecting inferiorly. After the neck of the aneurysm was clipped, the dome of the aneurysm was resected. The operation confirmed that the aneurysm had penetrated the right half of the optic chiasm and the thrombosed dome had also compressed the right optic tract. Although the aneurysm was successfully clipped, the visual disturbance persisted after surgery, suggesting that the damage to the visual pathways by aneurysm penetration was irreversible in this case.

Ten transitional internal carotid aneurysms are presented. Necks and domes of these aneurysms were located in both the intradural subarachnoid and extradural intracavernous spaces across the carotid dural ring. Seven aneurysms were small, 2 were large, and 1 was giant. Two patients had subarachnoid haemorrhage (SAH), 2 compressive symptoms, 5 SAH from rupture of associated lesions (aneurysms or AVM) and 1 case was an incidental finding. Direct clipping was performed successfully in all patients. The overall surgical outcome was excellent in all patients, with transient complications in 4 cases. It is suggested these aneurysms should be treated with direct clipping whether ruptured or not because of the risk of SAH. A classification of paraclinoidal region aneurysms including cavernous sinus aneurysms extending into the intradural subarachnoid space is proposed.

Polymer-encapsulated dopamine-secreting cell grafting is one of the most promising approaches for the treatment of Parkinson's disease. We microencapsulated dopamine secreting PC12 cells into agarose/poly(styrene sulfonic acid) complex and grafted them into the xenogeneic brain without immunosuppression. Dopamine secretion from the encapsulated cells was confirmed by high-performance liquid chromatography (HPLC) analysis before grafting. A large number of encapsulated PC12 cells survived in the brain 1 mo after transplantation and these cells were immunoreactive to tyrosine hydroxylase (TH) antibody, suggesting that these cells were secreting dopamine into the brain. There was no apparent immunological rejection or tumor formation. We concluded that microencapsulated PC12 cells survive in the xenogeneic brain without immunosuppression, and this grafting procedure is expected to be applied for the treatment of Parkinson's disease in the near future in combination with stereotaxic thalamotomy or pallidotomy.

Following polymer-encapsulation, human nerve growth factor-secreting baby hamster kidney fibroblasts (BHK-hNGF) were implanted into the striatum of hemiparkinsonian rats together with unencapsulated adrenal medullary chromaffin cells from either young (2 weeks) or old (12 months) donor rats. Animals receiving both BHK-hNGF cells and chromaffin cells exhibited significant decreases (39-56%) in apomorphine-induced rotational behaviour which was equivalent regardless of the age of the donor tissue. Histological analysis revealed that while survival of chromaffin cells without hNGF support was poor, co-grafts of adrenal medulla and BHK/hNGF cells increased chromaffin cell survival by 20 times. Again, this effect was independent of the age of the donor tissue. Retrieved capsules contained numerous viable encapsulated BHK-hNGF cells which continued to release hNGF. These results further indicate the potential use of intrastriatal implantation of encapsulated hNGF-secreting cells for augmenting the survival of co-grafted chromaffin cells as well as promoting the functional recovery of hemiparkinsonian rats.

Encapsulated cell grafting is one approach for the delivery of neurotransmitters and/or neurotrophic factors to the brain. Baby hamster kidney (BHK) cells were genetically modified to secrete high levels of human nerve growth factor (hNGF). Following polymer encapsulation, these cells were implanted into the left lateral ventricle or the left striatum 1.5 mm away from striatally cografted unencapsulated adrenal medullary chromaffin cells in hemiparkinsonian rats. Although the animals receiving adrenal medulla alone or adrenal medulla with intraventricular hNGF-secreting cell grafting did not show recovery of apomorphine-induced rotational behavior, the animals receiving adrenal medulla with intrastriatal hNGF-secreting cell implants showed a significant recovery of rotational behavior 2 and 4 weeks after transplantation. Histological analysis revealed that in animals receiving adrenal medulla with intraventricular hNGF-secreting cell grafting, the number of tyrosine hydroxylase-immunoreactive (TH-IR) surviving chromaffin cells tended to be higher (approximately five to six times) than in animals receiving adrenal medulla alone; however, this increase did not reach statistical significance. In contrast, in animals receiving adrenal medullary cells together with intrastriatal hNGF-secreting cells, the number of TH-IR surviving chromaffin cells was more than 20 times higher than that in animals receiving adrenal medullary cells alone. Analysis of retrieved capsules revealed that hNGF continued to be released by encapsulated BHK-hNGF cells after 4 weeks in vivo. Moreover, histological analysis confirmed the presence of numerous viable encapsulated BHK-hNGF cells. These results indicate the potential use of intrastriatal implantation of encapsulated hNGF-secreting cells for augmenting the survival of cografted chromaffin cells as well as promoting the functional recovery of hemiparkinsonian rats. These data indicate that this approach may have potential application for treating Parkinson's disease.

A 55-year-old woman with severe Parkinson's disease was treated by cografting adrenal medulla with pretransected peripheral nerve into the bilateral caudate nuclei. The patient showed modest improvement of her akinesia; this effect persisted for 1 year after transplantation, when she suddenly died from upper gastrointestinal bleeding unrelated to the grafting procedure. At autopsy, a large number of tyrosine hydroxylase-immunoreactive chromaffin cells were observed within the caudate graft sites and a dense network of host dopaminergic fibers was visualized. This autopsy finding is very important for the field of experimental and clinical chromaffin cell grafting because it is the first evidence that cografts using pretransected peripheral nerve might enhance the survival of chromaffin cells and the recovery of host dopaminergic fibers in humans suffering from Parkinson's disease.

PC12 cells were encapsulated within agarose/poly-(styrene sulfonic acid) (agarose/PSSa) mixed gel and xenotransplanted into the brains of guinea pigs. The immunoprotection capability and biocompatibility of the agarose/PSSa microcapsules were evaluated. Tyrosine hydroxylase-positive PC12 cells within the microcapsules were observed in all guinea pigs at least 5 weeks after transplantation. PC12 cells had a relatively uniform small size and occasionally formed cell clusters; however, cell necrosis was not apparent. The host reaction to agarose/PSSa microcapsules was minimal. The degree of glial fibrillary acidic protein-positive astrocyte density around the microcapsules was similar to that around the injection tracks. Necrosis around the brain/microcapsule interface was not apparent as assessed by Nissl staining. Normal-appearing neurons were observed in close vicinity to the capsule. High-performance liquid chromatography with electrochemical detection showed basal and potassium-evoked release of dopamine from the PC12 cell-enclosed microcapsules in vitro. We conclude that encapsulation using agarose/PSSa mixed gel can not only isolate the enclosed cells from the host immune system but can also allow diffusional exchange of nutrients and neurotransmitters. Encapsulation using agarose/PSSa mixed gel may expand the range of donor tissues for neural transplantation.

Since adrenal medullary chromaffin cells produce catecholamines as wel l as several kinds of neurotrophic factors which affect dopamine neurons, the authors have investigated the methods to increase the survival of grafted chromaffin cells in parkinsonian model animals. Measurement of nerve growth factor (NGF) showed that NGF level at the distal stump of the pretransected peripheral nerve increased significantly, thus, we have applied cografting of chromaffin cells with this stump of the peripheral nerve to animal models of Parkinson's disease since chromaffin cell survival have been reported to be increased by supplementation of nerve growth factor (NGF) in vitro and in vivo. By this cografting approach, not only the chromaffin cell survival but also the host intrinsic dopaminergic system recovery were enhanced. This effect continued 2 years in our long-term study The effects of donor and host ages were investigated and the results showed that the effects were more prominent when young donors or hosts were used compared with aging donors or hosts. Although cografting of adrenal medulla with peripheral nerve was applied successfully in parkinsonian patients with favorable results, it may be difficult to apply this procedure in aged patients since this is autografting and adrenal medulla itself may be affected by the disease in aged patients. Polymer-encapsulated dopamine-secreting cells are another donor candidates and can be applied combined with stereotaxic thalamotomy or pallidotomy for the patients with Parkinson's disease in the near future.

Encapsulation of neurosecretory cells within a semipermeable membrane may possibly isolate the enclosed cells from the host immune system and allow inward diffusion of nutrients and outward diffusion of neurotransmitters. Moreover, the encapsulation procedure may prevent the tumor formation of enclosed cells, when they are derived from tumor cells. In the present study, PC12 cells, a dopaminergic cell line derived from a rat pheochromocytoma, were enclosed within an agarose/poly (styrene sulfonic acid) (agarose/PSSa) mixture and transplanted into the brains of rats (allogeneic transplantation) or guinea pigs (xenogeneic transplantation). Tyrosine hydroxylase (TH) immunoreactive PC12 cells within the microcapsules were observed in all rats and guinea pigs at least up to five weeks after transplantation. PC12 cells were round in shape and of relatively uniform small size. Although PC12 cells occasionally formed cell clusters, the formation of a tumor was not observed. The host reaction to agarose/PSSa microcapsules was minimum. The degree of glial fibrillary acidic protein (GFAP) positive astrocyte density around the microcapsules was similar to that around injection tracks. There was no apparent immunological rejection around the capsules. High-performance liquid chromatography with electrochemical detection (HPLC-EC) showed basal and potassium-evoked release of dopamine from the PC12 cell-enclosed microcapsules in vitro. Although our data is preliminary, we believe that agarose/PSSa microcapsules are promising for producing semipermeable membranes that enable allo-and xenotransplantation of neurosecretory cells into the brain in the absence of systemic immunosuppression. This approach is expected to be applied in Parkinson's disease in the near future.

Neural transplantation is one of the promising approaches for the treatment of Parkinson's disease. Although the strategy of using adrenal medulla as donor tissue, rather than fetal nigra tissue, started as an alternative method, recent experimental studies demonstrated the efficacy of adrenal medulla grafting as a neurotrophic source. Many methods to increase the survival of grafted chromaffin cells have been developed, some of which have already been applied clinically with encouraging results. This review summarizes the advancements of adrenal medulla grafting in basic and clinical studies. Special attention is focused on the relationship with neurotrophic factors and how we can enhance the survival of grafted chromaffin cells.

We performed co-grafts of adrenal medulla and peripheral nerve into the bilateral caudate nuclei of a 43-year-old patient with advanced Parkinson's disease who showed severe daily motor fluctuations before surgery. There were no postoperative complications, and a 2-year follow-up result is presented. The patient showed a gradual and significant amelioration of the parkinsonian symptoms starting 2 weeks after transplantation. The alleviation of akinesia during "off" periods was the most apparent clinical improvement and continued for 2 years after surgery. The dosage of L-dopa/benserazide was significantly reduced after surgery compared with that before surgery. The results indicate that co-grafts of adrenal medulla with peripheral nerve may be useful for the treatment of Parkinson's disease in the long term.

Neovascularization within syngeneic rat fetal neocortical grafts transplanted into a previously prepared cavity in the cerebral cortex was studied 1 to 3 months after transplantation, utilizing scanning electron microscopy of vascular corrosion casts. The grafts were easily identified and the outer surface of the grafts, especially at the host-graft interface, was surrounded by large regenerated vessels of leptomeninges and connective tissue (e.g. dura). Large vessels originating from the choroid plexus also coated the grafts in animals whose lateral ventricles had been opened at the time of cavitation. These large regenerated vessels were mainly observed on the surface of the grafts, and they ramified markedly to form capillary networks in the vicinity of the host-graft interface. Occasionally several relatively large regenerated vessels were noted to extend into the grafts, and to ramify and connect with graft capillary networks having the same features as that of the host brain. Moreover, direct vascular connections between host capillaries and those within the grafts were observed. In some animals, arteries and arterioles which fed the grafts were identified in the perimeter of the grafts with their characteristic morphology. The interior microvasculature structure of the grafts was largely composed of the capillary network of graft origin, and of several relatively large penetrating vessels originating from the regenerated leptomeningeal vessels or the vessels of the choroid plexus. The present study demonstrated that the blood supply to the solid grafts transplanted into the previously prepared cavities originated primarily from the regenerated host vessels. These host vessels perfused the intrinsic graft vessels via new anastomoses which formed predominantly at the host-graft interface.

The present study was carried out to quantify the subsequent vascular regeneration around a lesion cavity made in the rat cerebral cortex and to decide the origin of the regenerated microvessels. A quantitative study utilizing computerized image analysis after microvascular perfusion with India ink indicated approximately 25 and 160% increase of the vascular density adjacent to the cavity compared to the contralateral cortex at 4 and 21 days, respectively, after lesioning. The microvasculature around the cavity was also evaluated by scanning electron microscopy of vascular corrosion casts. Newly formed leptomeningeal vessels began to grow down toward the floor of the cavity 4 days after lesioning and nearly covered the walls of the cavity 21 days after lesioning. A neovascular network of leptomeninges and connective tissue (e.g., dura) was formed as a roof over the cavity. Numerous branches of these newly formed vessels and prominent anastomoses with the capillary network in the walls and floor of the cavity were observed. Newly formed vessels also originated from the choroid plexus in cases where the lateral ventricle had been opened at the time of lesioning. These results document the plasticity of the vascular system in the cerebral cortex after a mechanical injury. The regenerated vascular network may offer a suitable condition for survival of transplanted tissues.

The nerve growth factor (NGF) level in the distal stump of mouse sciatic nerve transected 24 h before increased significantly compared with that in the nontransected contralateral side. This level was higher in aged (24-month-old) mice than in aging (12-month-old) or in young (1-month-old) mice. Adrenal medullary tissue mixed with the pretransected (24 h before) distal stump of the sciatic nerve of aged mice was cografted into the ipsilateral striatum of aged mice with a unilateral 6-hydroxydopamine lesion of dopaminergic system. Two and 4 weeks after transplantation, cografted mice showed partial functional compensation in amphetamine-induced motor asymmetry while mice with adrenal grafts alone did not show the functional recovery. The immunocytochemical staining of tyrosine hydroxylase revealed large numbers of chromaffin cells surviving in cografted animals. It is concluded that NGF level in the distal stump of pretransected peripheral nerve is increased even in aged animals and cografting of this nerve stump with adrenal medulla can be effectively utilized in aged animals with nigrostriatal insufficiency.

Nerve growth factor (NGF) concentration in the distal stump of the transected peripheral nerve has been shown to increase more than 20 times one day after transection. We performed adrenal medullary alone grafts or cografts of adrenal medulla and acutely transected or pretransected (24 h before) sciatic nerve into the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice, and compared the survival of chromaffin cells and the recovery of the host-intrinsic dopaminergic fibers using tyrosine hydroxylase immunocytochemistry and high-performance liquid chromatography. We also performed peripheral nerve alone grafting (acutely transected or pretransected) for comparison. Adrenal medullary chromaffin cells cografted with pretransected sciatic nerve survived better than those in adrenal grafts alone or those cografted with acutely transected sciatic nerve. Host dopaminergic fiber recovery was also most prominent in mice cografted with pretransected peripheral nerve. Animals receiving grafts of peripheral nerve alone showed limited recovery of host dopaminergic fibers and the degree of recovery was lower than that of animals receiving cografts of adrenal medulla with pretransected peripheral nerve. We conclude that pretransected peripheral nerve enhanced the survival of cografted chromaffin cells and this increased survival led to promote the recovery of host-intrinsic dopaminergic fibers. This grafting procedure might be promising in application to patients with Parkinson's disease.

Accumulation of nerve growth factor (NGF) has been reported to occur at the distal stump of pretransected peripheral nerve. We performed adrenal medullary grafts or cografts of adrenal medulla and distal stump of pretransected peripheral nerve into the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated young or aging mice. We subsequently compared the survivability of chromaffin cells and the degree of host dopaminergic (DA) fiber recovery in relation to host age. In both young and aging hosts, adrenal medullary chromaffin cells cografted with pretransected peripheral nerve survived better than those in adrenal grafts alone. Host DA fiber recovery, however, showed less recovery and more restriction around the grafted site in aging compared with young hosts. We conclude that pretransected peripheral nerve can enhance the survivability of cografted chromaffin cells both in young and in aging hosts, but that DA fiber recovery is more limited in aging hosts compared to young hosts.

This report describes the long-term operative outcome of 72 patients with spina bifida cystica. The period of follow-up was between 4 and 20 years. In our series, 17 patients died, with the mortality rate increasing as the lesions were more rostral. All cases involving only a meningocele are living without handicap. The cases of spina bifida cystica with hydrocephalus had higher morbidity and mortality when compared to those without hydrocephalus. We conclude that the rostro-caudal location, the content of the sac, and whether there is associated hydrocephalus are important factors influencing the long-term prognosis of spina bifida cystica.

Foetal rat mesencephalic dopamine-containing tissue was transplanted into the lateral ventricle of mice previously subjected to a 6-OHDA lesion of dopaminergic nerve terminals in the corpus striatum. The graft recipients were immunosuppressed by subcutaneous injections of 15-deoxyspergualin (DSG). Four weeks postgrafting, all DSG-treated mice showed partial or complete functional compensation in amphetamine-induced motor asymmetry. The immunohistochemical staining of tyrosine hydroxylase (TH) revealed large numbers of surviving dopamine neurons and abundant fibers in the grafted animals. In contrast, all grafts in non-DSG-treated animals were rejected and functional compensation was lacking. It is concluded that DSG treatment promotes xenogeneic intracerebral graft survival, recovery of function and reduce the histological sign of rejection.

Pretransected peripheral nerve has been demonstrated to enhance the survival of cografted adrenal medullary chromaffin cells and the recovery of host dopaminergic (DA) systems in animal models of Parkinson's disease. In the present study, we examined the effect of donor age on survival of cografted chromaffin cells. Adrenal medulla and pretransected peripheral nerve from young (1-month-old) or aging (12-month-old) donors were cografted into the striatum of MPTP-treated young (2-month-old) C57/BL mice. Although chromaffin cell survivability was increased by cografting with pretransected peripheral nerve despite donor age, survivability of chromaffin cells from aging donors was less than that using young donors. Image analysis of striatal DA fibers and chemical analysis of striatal DA showed that cografting with pretransected peripheral nerve enhanced the recovery of striatal DA systems more prominently than adrenal grafting alone. However, this effect was less in mice receiving aging donor tissues compared with mice receiving young donor tissues.

Trophic factor supplementation has been reported to enhance the survivability of grafted adrenal chromaffin cells. Because the content of nerve growth factor in the distal stump of a pretransected peripheral nerve increases markedly 1 day after transection, we injected cografts of adrenal medulla with pretransected peripheral nerve into the striata of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice and performed follow-up histological and neurochemical analyses over a 12-month period. Adrenal medullary chromaffin cells cografted with pretransected peripheral nerve survived better than in adrenal grafts alone at 1, 3, and 12 months after transplantation. Host dopaminergic fiber recovery adjacent to the grafts was more prominent in mice with cografts than in mice with adrenal grafts alone at 1 and 3 months after transplantation. Twelve months after transplantation, however, there was no significant difference between the two groups of animals because of the natural recovery of intrinsic dopaminergic fibers from MPTP toxicity. Dopamine concentration in the striata of cografted mice was higher than in mice with adrenal grafts alone at 1 month after transplantation. At 3 and 12 months after transplantation, the natural recovery of dopamine concentration from MPTP toxicity was apparent in both groups of animals and no significant difference was observed between the groups. We conclude that adrenal medullary chromaffin cells can survive for at least 12 months after grafting when cografted with pretransected peripheral nerve. Cografts enhanced the recovery of the host nigrostriatal dopaminergic system up to 3 months after transplantation, but this enhancement was not apparent at 12 months because of the natural recovery of dopaminergic fibers from MPTP toxicity.

In this study, the immunosuppressive effect of 15-deoxyspergualin (DSG) on the survivability of rat embryonic dopaminergic neurons grafted into the lateral ventricle of adult mice was investigated. DSG was administered daily in dose of 5 mg/kg for 2 weeks postgrafting, commencing on the day of transplantation, in the immunosuppressant-treated groups. Animals were then allowed to survive for 2 to 4 weeks after transplantation. Histological analysis revealed that most of transplanted rat fetal neural tissue was destroyed and scavenged in 2 weeks after transplantation in the non-immunosuppressed group. However, a large number of tyrosine hydroxylase (TH)-positive grafted neurons survived and grew postgrafting in the brain of the host administered with DSG even if they suffered from T lymphocyte infiltrations visualized by cytotoxic T cell immunohistochemistry. The results thus indicated that DSG is an potent immunosuppressant in neural transplantation as well as in transplantation of other organs in animals. It seems to be able to block, at least in part, the ability of mature specific cytotoxic T cells to lyse their targets.