Anterior cingulotomy for refractory obsessive-compulsive disorder

OBJECTIVE

This study was designed to prospectively investigate the efficacy and cognitive adverse effects of stereotactic bilateral anterior cingulotomy as a treatment for refractory obsessive-compulsive (OCD) patients for 12 months.

METHOD

Patients were eligible if they had severe OCD and rigorous treatments had been unsuccessful. Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Clinical Global Impression (CGI) and neuropsychological tests were used to assess the efficacy and cognitive changes of cingulotomy before and 12 months after operation.

RESULTS

The mean improvement rate of the Y-BOCS scores achieved from baseline was 36.0%. Out of 14 patients six met responder criteria; 35% or higher improvement rate on Y-BOCS and CGI improvement of very much or much better at 12-month follow-up. There was no significant cognitive dysfunction after cingulotomy.

CONCLUSION

Anterior cingulotomy shows few cognitive adverse effects, with about half of the OCD patients demonstrating significant symptomatic improvement.

Complications after gamma knife radiosurgery for benign meningiomas

OBJECTIVES

To analyse the results of gamma knife radiosurgery (GKS) for the treatment of intracranial meningiomas and to assess possible factors related to the outcome and complications of such treatment.

METHODS

The authors retrospectively reviewed the clinical and radiological data of 179 patients (194 lesions) treated with GKS for meningiomas between May 1992 and October 2000. The mean follow up duration was 37.3 months (range 6.4 to 86.3 months). The study determined the correlation between radiosurgical outcome including imaging changes after GKS and multiple factors such as tumour location and size, patient characteristics, venous sinus status, pre-GKS degree of oedema, other treatment modalities, and radiosurgical parameters.

RESULTS

The radiological control rate was 97.1%. Magnetic resonance imaging (MRI) showed complications after GKS in 35 lesions (25.0%) among the 140 lesions followed up with MRI. Complications were divided into peritumorous imaging changes (33 lesions; 23.6%) and transient cranial nerve dysfunction (two lesions; 1.4%). Radiation induced imaging changes were seen mostly in convexity, parasagittal, and falx meningiomas that were deeply embedded in the cortex. About 60% of these were asymptomatic and the overall rate of symptomatic imaging changes was 9.3%. Neurological deficit related to imaging changes developed in only three patients, and all the symptoms were transient.

CONCLUSION

GKS for intracranial meningiomas seems to be a safe and effective treatment. However, meningiomas of the convexity, parasagittal region, or falx cerebri have a higher incidence of peritumorous imaging changes after GKS than those of the skull base. Therefore, the use of GKS needs to be considered very cautiously in cerebral hemispheric meningiomas, taking into consideration patient age and general condition, tumour size and location, pattern of cortical embedding, relation between the tumour and venous sinuses, presenting symptoms, and patient preference.

Neurophysiological identification and characterization of thalamic neurons with single unit recording in essential tremor patients

This study investigated the characteristics of the neuronal activities of the motor thalamus (Vim and Vop) in essential tremor (ET) patients, and compared the results with those of Parkinson's disease (PD) patients. The kinetic (Ki) neurons were found mainly in the Vim, whereas the voluntary (Vo) neurons were found principally in the Vop of ET patients. The mean firing rates of the ET patients were higher than those of the PD patients. In addition, the mean firing rates of the Ki neurons of the ET patients were higher than those of the PD patients in the Vim nuclei. However, the mean firing rates of the ventralis caudalis (Vc) neurons, which respond to sensory stimulation, were similar in each group. An analysis of the incidence of bursting neurons revealed that the Vop nucleus of the ET patients had less bursting neurons than the PD patients. However, in the Vim nucleus, both groups possessed bursting neurons even though the incidence was slightly different. Tremor cells were observed less frequently in the Vim nucleus of ET patients than in the PD patients. This study demonstrated the characteristic features of the neuronal activities of ET patients compared to those of PD patients.

Microvascular decompression for hemifacial spasm: a long-term follow-up of 1,169 consecutive cases

We analyzed the records of 1,169 patients with hemifacial spasm (HFS) who underwent microvascular decompression (MVD) and were followed up for more than 6 months from January 1987. The mean follow-up duration was 23.8 months (6-145 months). Excellent surgical outcome was obtained in 90.5% and good in 4.5%, giving an overall success rate of 95.0%. There was statistically significant relationship between vertebral artery (VA) shift and side of symptom. Permanent facial weakness and hearing impairment were 1.4% and 2.3%, respectively. There were no anatomical differences at the root entry zone (REZ) and significant differences of surgical outcome in young HFS (34 patients). Factors such as type of offender, severity of compression on the facial nerve root, and the degree of decompression of the REZ on postoperative MRI did not correlate with surgical outcome.

Gamma knife radiosurgery for metastatic brain tumors

We reviewed our series of metastatic brain tumors treated by Gamma Knife Radiosurgery. From May 1992 to January 2001, 115 consecutive patients with 425 lesions were treated over 128 treatment sessions. Forty three patients were known to have died at the end of the recording period. The mean follow-up duration was 11.6 months and mean number of lesions was 3.5. The most common primary sites were lung and breast. Mean tumor volume was 4.2 cm(3) and mean margin dose was 16.2 Gy. 6-month, 1-year, and 18-month survival rates were 73.6, 58, and 46%, respectively. Multivariate analysis revealed that higher KPS scores, no evidence of extracranial metastasis, and controlled primary disease were significantly related to longer survival. Adjuvant whole brain irradiation did not significantly influence on the prolongation of survival time and local control of radiosurgically treated lesions.

Unilateral globus pallidus internus stimulation improves delayed onset post-traumatic cervical dystonia with an ipsilateral focal basal ganglia lesion

Treatment with unilateral left globus pallidus internus (GPi) deep brain stimulation is reported in a patient with severe delayed onset post-traumatic cervical dystonia. He had sustained severe head trauma at the age of 17 and had developed a mild right hemiparesis. Three years after the head injury, cervical dystonia with head turning to the left side developed. Magnetic resonance imaging (MRI) showed a discrete GPi lesion on the left side. At the age of 23, he underwent unilateral left GPi deep brain stimulation. He experienced immediate but short lasting benefit from the microlesioning effect of the electrode. With activation of deep brain stimulation, there was significant improvement of the cervical dystonia, persisting for 12 months of follow up. This case underlines the importance of the globus pallidus internus in the generation and amelioration of cervical dystonia.

A site-specific mutation of tyrosine hydroxylase reduces feedback inhibition by dopamine in genetically modified cells grafted in parkinsonian rats

Aromatic L-amino acid decarboxylase (AADC) is necessary for conversion of L-DOPA to dopamine. Therefore, AADC gene therapy has been proposed to enhance pharmacological or gene therapies delivering L-DOPA. However, addition of AADC to the grafts of genetically modified cells expressing tyrosine hydroxylase (TH) and GTP cyclohydrolase 1 (GCH1), which produce L-DOPA in parkinsonian rats, resulted in decreased production of L-DOPA and dopamine owing to feedback inhibition of TH by dopamine. End-product feedback inhibition has been shown to be mediated by the regulatory domain of TH, and site-specific mutation of serine 40 makes TH less susceptible to dopamine inhibition. Therefore, we investigated the efficacy of using TH with serine 40 mutated to leucine (mTH) in an ex vivo gene-therapy paradigm. Primary fibroblasts (PF) from Fischer 344 rats were transduced with retrovirus to express mTH or wild-type rat TH cDNA (wtTH). Both cell types were also transduced with GCH1 to provide the obligate TH cofactor, tetrahydrobiopterin. PF transfected with AADC were used as coculture and cografting partners. TH activities and L-DOPA production in culture were comparable between PFwtTHGC and PFmTHGC cells. In cocultures with PFAADC cells, PFmTHGC cells showed significant reduction in the inhibitory effect of dopamine compared with PFwtTHGC cells. In vivo microdialysis measurement showed that cografting PFAADC cells with PFmTHGC cells resulted in smaller decreases in L-DOPA and no reduction in dopamine levels compared with cografts of PFAADC cells with PFwtTHGC cells, which decreased both L-DOPA and dopamine levels. Maintenance of dopamine levels with lower levels of L-DOPA would result in more focused local delivery of dopamine and less potential side-effects arising from L-DOPA diffusion into other structures. These data support the hypothesis that mutation of serine 40 attenuates TH end-product inhibition in vivo and illustrates the importance of careful consideration of biochemical pathways and interactions between multiple genes in gene therapy.

The role of inducible nitric oxide synthase in aseptic loosening after total hip arthroplasty

We collected 16 samples of the membrane which surrounds loose hip prostheses from patients undergoing revision operations for aseptic loosening. To serve as the control group, samples of the synovial tissue and the fibrous capsular tissue were collected from 11 patients undergoing primary hip arthroplasties. Analyses of the expression levels of inducible nitric oxide synthase (iNOS), tumour necrosis factor-alpha (TNF-alpha), and cytosolic phospholipase A2 (cPLA2) mRNAs were performed by a reverse transcription polymerase chain reaction, and the content of nitrite was measured by the Griess reaction using sodium nitrite as the standard. The expression levels of iNOS, TNF-alpha, and cPLA2 mRNAs in the membranes were significantly higher than those in the control samples (p < 0.05). The expression levels of iNOS mRNA and the nitrite content in the membranes significantly correlated with those of TNF-alpha and cPLA2 mRNAs, respectively. In addition, the expression levels of iNOS, TNF-alpha, and cPLA2 mRNAs were significantly higher in membranes from cementless than in those from cemented implants (p < 0.05). Our results suggest that the expression levels of iNOS, TNF-alpha, and cPLA2 mRNAs in the membranes are regulated by closely-related mechanisms and that these have a significant role in aseptic loosening.

Ictal electrocorticographic findings related with surgical outcomes in nonlesional neocortical epilepsy

PURPOSE

To characterize ictal electrocorticographic features related to surgical outcomes in nonlesional neocortical epilepsy (NE).

METHODS

We analyzed 187 ictal electrocorticograms (ECoG) obtained from 18 patients who had undergone presurgical evaluation and subsequent neocortical resections (frontal: seven, parietal: one, occipital: four, multilobar: six). None of them had any MRI-detectable lesions. Various ECoG data sets recorded from eight patients who achieved a favorable surgical outcome (either seizure free or more than 90% reduction of seizure frequencies) were compared with that from ten patients with unfavorable outcome (less than 90% reduction of seizure frequencies) (follow up duration: 47+/-11 months).

RESULTS

Reproducible ictal onset zone (IOZ) in recurrent seizures (P=0.013) and persistent ictal discharges in IOZ from the onset to the end of seizure (P=0.004) were found more frequently in the patients with good outcome. Ictal onset patterns consisting of low voltage fast or high amplitude beta spikes predicted a good surgical outcome while rhythmic sinusoidal activity or rhythmic spike/sharp waves of slow frequency were predictive of poor outcome (P=0.01). The ictal onset rhythm consisting of gamma or beta frequencies was more prevalent in the favorable group (P=0.015).

CONCLUSIONS

The presence of stable ictal circuit suggested by the consistent earliest activation of specific electrodes in the repetitive seizures (reproducible IOZ) and the active participation of IOZ throughout the attack were valuable prognostic factors in addition to the morphology and frequency of ictal onset rhythm.

Radiologically confirmed de novo glioblastoma multiforme and hippocampal sclerosis associated with the first onset of nonconvulsive simple partial status epilepticus

The authors report a case of an unusual progression of glioblastoma multiforme in the temporal lobe associated with the first onset of nonconvulsive simple partial status epilepticus (SPSE), a rare form of status epilepticus. The patient underwent a left temporal craniotomy and the tumor was removed. Concurrently, the hippocampus was removed as well. The pathological diagnosis of the tumor and the hippocampus were glioblastoma multiforme and hippocampal sclerosis. The patient's postoperative course was uneventful.

Synthesis of substituted-(l)-tryptophanols from an enantiomerically pure aziridine-2-methanol

Enantiomerically pure (l)-tryptophanol (5) was synthesized from 4(R)-iodomethyl-2-oxazolidinone (2) and indolylmagnesium bromide in three steps (52% overall yield). Using this procedure, we also prepared various tryptophanols with substituent(s) on the indole ring. Furthermore, optically active 4(R)-iodomethyl-2-oxazolidinone was readily prepared from an enantiomerically pure aziridine-2(S)-methanol in high yield. [reaction: see text]

The efficacy and safety of risperidone for the treatment of geriatric psychosis

Risperidone is an atypical antipsychotic drug which has been suggested to be beneficial for the treatment of elderly patients with psychotic symptoms. In this study, we assessed the short-term efficacy and the safety of risperidone in geropsychiatric inpatients with psychotic symptoms. The sample population included 110 elderly inpatients with psychotic disorders. Assessment for drug efficacy using the Brief Psychiatric Rating Scale, Sandoz Clinical Assessment-Geriatric scale, and Clinical Global Impression scale was conducted at baseline and also at 4 weeks subsequent to risperidone treatment commencement. Subsequent to commencing risperidone treatment, 80 patients completed a 4-week therapeutic evaluation. Seventy (87.5%) of the 80 patients experienced mild to substantial improvement using the Clinical Global Impression scale. Adverse effects were monitored in all 110 patients. The most commonly detected adverse effects were weakness of legs or walking problems (43/110; 39.1%) and dizziness (32/110; 29.1%). Peripheral edema was noted in 18 (16.4%) patients. Risperidone, in low doses, appeared to have been effective in this sample of patients older than 65 years with psychotic symptoms. The mean dose (2.1 +/- SD 1.4 mg/day) applied was lower then that suggested for young patients and was related to the each specific patient diagnosis. Peripheral edema and walking problems were commonly observed adverse effects for these elderly patients, such problems having not been seen to the same extent in previous studies of young patients.

Augmented expression of peroxiredoxin I in lung cancer

Comparative proteome analysis was performed between human normal (BEAS 2B) and malignant (A549) lung epithelial cells in an attempt to identify novel biomarkers of lung cancer. Approximately 500 protein spots could be separated by mini two-dimensional electrophoresis and visualized with Coomassie blue R-250. Among those relatively abundant proteins, eight spots were changed more than twofold reproducibly and identified by peptide mass fingerprints using mass spectrometry and database search. The increased proteins in A549 were aldehyde dehydrogenase, peroxiredoxin I, fatty acid binding protein, aldoketoreductase, and destrin, whereas the decreased proteins were galectin-1, transgelin, and stathmin. Since human lung is exposed to continuous oxidative stress, antioxidant enzyme peroxiredoxin I was selected for further investigation and its augmented expression was confirmed in cancer tissues compared to normal tissues from lung cancer patients, suggesting peroxiredoxin I as a potential biomarker of lung cancer.

Two-dimensional gel analysis of secreted proteins induced by interleukin-1 beta in rat astrocytes

Interleukin-1 beta (IL-1 beta) is a pro-inflammatory cytokine produced in the brain by endogenous microglial cells responding to injury. Levels of IL-1 beta are elevated in several neurodegenerative disorders, including Alzheimer's disease. IL-1 beta, which can act as a mitogen for astrocytes, also elicits the expression and secretion of multiple factors and paracrine 'second messengers' such as other cytokines, nerve growth factor, prostaglandins and nitric oxide that may in turn modulate neuronal and glial responses to injury. Utilizing giant, high-resolution two-dimensional gel electrophoresis, we have sought to more fully define the potential range of protein mediators that are secreted by astrocytes treated with IL-1 beta. In cultured rat astrocytes, we observe dramatic increases in the secretion of eight different protein species after 24 h of treatment with human recombinant IL-1 beta (1 U/ml). Seven of the proteins are also induced by tumor necrosis factor-alpha or basic fibroblast growth factor. Based on immunoprecipitation with specific antisera, we have identified three of these proteins as plasminogen activator inhibitor type-1, ceruloplasmin, and complement component C3. The identities of the other proteins, including the IL-1 beta-specific induction, are currently unknown. Characterization of these downstream modulators of IL-1 beta action complements gene-based approaches and will provide a better understanding of astrocyte responses to injury as well as markers for astrocyte activation in neurodegenerative diseases.

Characteristics of Chinese suicide attempters admitted to a geropsychiatric unit

PURPOSE

To investigate the characteristics for elderly Chinese suicide attempters in Taiwan and make comparisons with Western reports.

METHODS

During a six-year period, patients admitted to a geropsychiatric unit as a result of a suicide attempt were investigated for factors related to the suicide attempt.

RESULTS

Of the 722 admissions during this period, 55 (7.6%) were patients who had been admitted due to suicide attempt. The sex and age distributions for the suicide attempters were similar to those for other patients. The most common diagnoses were depressive disorders (56.4%), followed by delusional disorders (20.0%). A total of 121 suicide motives were cited for the 55 attempters, an average of 2.2 per person, with depressive symptoms commonly found on admission. During the first week of hospitalization, 53 attempters (96.4%) still exhibited suicidal ideation and six patients made a further suicide attempt, however, only three patients retained suicidal ideation on discharge.

CONCLUSIONS

Our study confirms previous Western reports that depressive disorders are commonly manifested in elderly suicide attempters. There were differences in the motives and methods employed for the suicides, possibly due to cultural difference and/or sample source. Most of the suicide attempters exhibited a favourable response with hospitalization.

Outcome of renal transplantation in hepatitis B surface antigen-positive patients after introduction of lamivudine

BACKGROUND

In end-stage renal disease patients with hepatitis B surface antigen (HBsAg), the risk of hepatic dysfunction after immunosuppression represents a large barrier in renal transplantation. Lamivudine is a potent inhibitor of hepatitis B virus (HBV) replication. We retrospectively investigated the outcome of HBsAg-positive renal transplantation recipients after lamivudine had become available.

METHODS

From July 1994 to August 2000, seventeen HBsAg-positive patients (M:F=15:2) received renal allografts (13:4=living:cadaveric donors). Liver function tests at the time of transplantation were normal in all patients. Pre-transplant liver biopsies performed in 15 patients demonstrated minimal inflammatory histology, except in three patients showing pathological and clinical signs of active hepatitis. Lamivudine was started pre-operatively in these three subjects. Another seven patients were treated with lamivudine for post-operative hepatic dysfunction. The remaining seven patients did not develop hepatic dysfunction after transplantation.

RESULTS

Lamivudine was initially effective in decreasing serum HBV DNA titres, and in normalizing hepatic enzymes. Lamivudine was well tolerated without significant side effects for 35.5+/-8.9 months after initiation of treatment. HBV DNA became negative in nine patients but remained positive in one patient. Among the nine patients with initial negative conversion of HBV DNA, two developed transient positive conversion of HBV DNA and two demonstrated persistent positive conversion. Among the patients with normal liver histology in the pre-transplant period, 41.6% (5/12) developed liver pathology progression after immunosuppression. All 17 patients had functioning grafts, except for one patient who developed relapsed IgA nephropathy.

CONCLUSIONS

Our data showed relatively favourable outcomes in hepatitis B-positive renal transplant recipients receiving lamivudine treatment, even though two patients developed lamivudine resistance.

Rudimentary TCR signaling triggers default IL-10 secretion by human Th1 cells

Understanding the process of inducing T cell activation has been hampered by the complex interactions between APC and inflammatory Th1 cells. To dissociate Ag-specific signaling through the TCR from costimulatory signaling, rTCR ligands (RTL) containing the alpha1 and beta1 domains of HLA-DR2b (DRA*0101:DRB1*1501) covalently linked with either the myelin basic protein peptide 85-99 (RTL303) or CABL-b3a2 (RTL311) peptides were constructed to provide a minimal ligand for peptide-specific TCRs. When incubated with peptide-specific Th1 cell clones in the absence of APC or costimulatory molecules, only the cognate RTL induced partial activation through the TCR. This partial activation included rapid TCR zeta-chain phosphorylation, calcium mobilization, and reduced extracellular signal-related kinase activity, as well as IL-10 production, but not proliferation or other obvious phenotypic changes. On restimulation with APC/peptide, the RTL-pretreated Th1 clones had reduced proliferation and secreted less IFN-gamma; IL-10 production persisted. These findings reveal for the first time the rudimentary signaling pattern delivered by initial engagement of the external TCR interface, which is further supplemented by coactivation molecules. Activation with RTLs provides a novel strategy for generating autoantigen-specific bystander suppression useful for treatment of complex autoimmune diseases.

Ictal automatisms with preserved responsiveness in a patient with left mesial temporal lobe epilepsy

PURPOSE

To describe the possible mechanism of ictal automatisms with preserved responsiveness (APRs) in a patient with left mesial temporal lobe epilepsy, which had not been reported previously.

METHODS

Ictal EEGs recorded from bilateral foramen ovale electrodes with scalp-sphenoidal electrodes were analyzed in respect to the ictal semiology.

RESULTS

The patient had a right hemispheric language dominance in the dextral. Electroclinical analysis revealed that the onset of oroalimentary automatisms coincided with the involvement of the left mesial and lateral temporal structures by spreading ictal discharges. The ictal discharge spreading was limited to the ipsilateral hemisphere throughout the seizure, which explained the intact consciousness and preserved responsiveness of the patient.

CONCLUSIONS

This case suggests that APRs take place in seizures originating from the nondominant temporal lobe, during which ipsilateral mesial and lateral temporal structures are diffusely involved without spreading to the contralateral side.

Microvascular decompression in trigeminal neuralgia: a correlation of three-dimensional time-of-flight magnetic resonance angiography and surgical findings

We analyzed 104 patients with trigeminal neuralgia who underwent microvascular decompression and who were followed up for more than 12 months during the period from January 1992 to June 1998. In this recent series, we utilized three-dimensional time-of-flight magnetic resonance angiography (3D-TOF MRA) for all patients with trigeminal neuralgia. A 3D-TOF MRA was beneficial in treatment planning and in predicting surgical outcome by demonstrating cranial nerve compression as well excluding other etiologies such as tumor or vascular lesions. The patients were followed up for 1-7 years (mean 5.7 +/- 1.2 years). Initial pain relief was complete in 89 patients (85.6%) and partial in 12 patients (11.5%). There were three primary failures (2.9%). The acceptable pain relief rate (complete relief: 79.8%, partial relief: 11.5%) was determined in the long-term follow-up of surgical results. Pain recurred in 6 patients (5.8%). The mean time to recurrence was 48 months (36-93 months). There were no serious or annoying complications such as anesthesia dolorosa.

Design, engineering, and production of human recombinant t cell receptor ligands derived from human leukocyte antigen DR2

Major histocompatibility complex (MHC) class II molecules are membrane-anchored heterodimers on the surface of antigen-presenting cells that bind the T cell receptor, initiating a cascade of interactions that results in antigen-specific activation of clonal populations of T cells. Susceptibility to multiple sclerosis is associated with certain MHC class II haplotypes, including human leukocyte antigen (HLA) DR2. Two DRB chains, DRB5*0101 and DRB1*1501, are co-expressed in the HLA-DR2 haplotype, resulting in the formation of two functional cell surface heterodimers, HLA-DR2a (DRA*0101, DRB5*0101) and HLA-DR2b (DRA*0101, DRB1*1501). Both isotypes can present an immunodominant peptide of myelin basic protein (MBP-(84-102)) to MBP-specific T cells from multiple sclerosis patients. We have previously demonstrated that the peptide binding/T cell recognition domains of rat MHC class II (alpha1 and beta1 domains) could be expressed as a single exon for structural and functional characterization; Burrows, G. G., Chang, J. W., Bächinger, H.-P., Bourdette, D. N., Wegmann, K. W., Offner, H., and Vandenbark A. A. (1999) Protein Eng. 12, 771-778; Burrows, G. G., Adlard, K. L., Bebo, B. F., Jr., Chang, J. W., Tenditnyy, K., Vandenbark, A. A., and Offner, H. (2000) J. Immunol. 164, 6366-6371). Single-chain human recombinant T cell receptor ligands (RTLs) of approximately 200 amino acid residues derived from HLA-DR2b were designed using the same principles and have been produced in Escherichia coli with and without amino-terminal extensions containing antigenic peptides. Structural characterization using circular dichroism predicted that these molecules retained the antiparallel beta-sheet platform and antiparallel alpha-helices observed in the native HLA-DR2 heterodimer. The proteins exhibited a cooperative two-state thermal unfolding transition, and DR2-derived RTLs with a covalently linked MBP peptide (MBP-(85-99)) showed increased stability to thermal unfolding relative to the empty DR2-derived RTLs. These novel molecules represent a new class of small soluble ligands for modulating the behavior of T cells and provide a platform technology for developing potent and selective human diagnostic and therapeutic agents for treatment of autoimmune disease.

Microvascular decompression of the facial nerve for the treatment of hemifacial spasm: preoperative magnetic resonance imaging related to clinical outcomes

BACKGROUND

The objective of this study was to investigate the role of preoperative three dimensional short-range magnetic resonance angiography (3D-TOF MRA) in predicting the clinical outcomes following microvascular decompression for the treatment of hemifacial spasm.

METHOD

Preoperative magnetic resonance (MR) imaging was performed on all patients with hemifacial spasm (564 cases) between January 1992 and September 1998. Of the 564 patients, 440 patients were included in this retrospective study. The presence of vascular contact, offenders, and anomalies in the vertebro-basilar system, were determined by 3D-TOF MRA prior to microvascular decompression of the facial nerve. The preoperative findings were compared with the surgical findings and clinical outcomes. Findings. A correlation was found between the clinical outcome (p < 0.01) and the presence of a vascular indentation at the root entry zone (REZ) of the facial nerve. A shift of the vertebrobasilar system to the symptomatic side was found in 214 (48.6%) patients with hemifacial spasm, compared to only 10 (13.5%) patients in the control group (p < 0.01). The unilateral vertebral artery was observed in 43 (9.8%) patients with hemifacial spasm and in 8 (10.8%) of the control patients. A hypoplasia of the artery was found in 8 (1.8%) patients with hemifacial spasm and in 1 (1.4%) control patient. The compressing offenders in the patients, discovered by MRI in conjunction with MRA, were as follows: 45.9% (202 patients) in the anterior inferior cerebellar artery (AICA), 34.8% (153 patients) in the posterior inferior cerebellar artery (PICA), 12.5% (55 patients) in the vertebral artery (VA) and 6.8% (30 patients) in multiple vessels. In contrast to the compressing offenders seen on the MRA, the offenders confirmed during surgery were as follows: 43% (189 patients) in the AICA, 36.4% (160 patients) in the PICA, 1.4% (6 patients) in the VA, 19% (84 patients) in multiple vessels, and 0.2% (1 patient) in the vein. In our long-term follow-up series of the 440 patients with hemifacial spasm, an excellent surgical outcome was obtained in 86.3% of cases and a good outcome was achieved in 6.4% (mean follow-up duration, 45.5 months).

INTERPRETATION

Preoperative 3D-TOF MRA can identify the relationship between the facial nerve and adjacent vessels in patients with a hemifacial spasm and assist in preoperative planning. This study suggests that 3D-TOF MRA is useful for selecting appropriate patients for surgical treatment and, to some extent, as an additional role for predicting the clinical outcome.

Microvascular decompression of the facial nerve for hemifacial spasm in youth

OBJECTS

The goal of this study was to investigate the differences between clinical findings in youth and in adulthood on microvascular decompression (MVD) of the facial nerve for the treatment of hemifacial spasm (HFS).

METHODS

We retrospectively evaluated 855 patients who underwent MVD from January 1985 to July 1999. In our series of 33 young HFS patients, all patients had definite offending vessels. Interestingly, pathologic tortuous vertebral artery as a possible etiology was more rarely observed in young HFS patients (1/33 patients, 3.0%) than in adult patients (61/822 patients, 7.4%) (P < 0.05). We did not observe any atomical variations of the vessels or any arachnoidal thickening around the root entry zone and cerebellopontine cistern in youths. Furthermore, young HFS patients did not necessarily have poorer surgical outcomes than adult HFS patients.

CONCLUSIONS

Our results suggest that the cause and progress of HFS are the same in youth as in adulthood, even though the pathogenesis of early onset remains unclear.

Highly diastereoselective Michael addition of alpha-hydroxy acid derivatives and enantioselective synthesis of (+)-crobarbatic acid

[reaction: see text]. Michael addition of enolates of 2a and 2b to alpha,beta-unsaturated esters took place selectively on different faces (Si and Re, respectively) of the double bond to give the corresponding products 4 and 5, respectively, with >98% de. Subsequent hydrolysis of these Micheal adducts gives 3,4-disubstituted gamma-lactones with high enantiomeric excesses.

Gene therapy for Parkinson's disease: determining the genes necessary for optimal dopamine replacement in rat models

This article reviews the mechanism of dopamine delivery in the CNS in order to determine the optimal set of genes for effective gene therapy in Parkinson's disease (PD). Systematic neurobiological investigation of the biochemical steps has revealed that tyrosine hydroxylase (TH), which has been used in earlier studies, functions only when the essential cofactor, tetrahydrobiopterin (BH1) is present. Transduction of the gene for GTP cyclohydrolase I, the first and rate-limiting step in BH1 synthesis, along with the TH gene, generated cells that are capable of producing L-DOPA spontaneously both in vitro and in vivo. When the aromatic L-amino acid decarboxylase (AADC) gene was added as a third gene, in an attempt to increase the conversion of L-DOPA to dopamine, feedback inhibition by the end product, dopamine, on TH activity resulted. To circumvent this problem, we employed a complementary strategy. Gene transfer of the vesicular monoamine transporter was combined with AADC and produced genetically modified cells that can convert L-DOPA to dopamine and store it for gradual release. This approach provided a means to regulate final dopamine delivery by controlling precursor doses and to achieve more sustained delivery of dopamine. Our investigation into determining the genes necessary for optimal dopamine delivery has been facilitated by in vivo biochemical assays using microdialysis. This technique has provided us with a clear and quantitative tool to compare the effects of various genes involved in dopamine synthesis and processing.

Efficient gene transfer of VSV-G pseudotyped retroviral vector to human brain tumor

A retroviral vector constructed from the murine leukemia virus (MLV) can only express transgenes in cells undergoing mitosis, indicating its suitability as a delivery vehicle for cancer gene therapy. However, the transduction efficiency (TE) of retroviruses embedding endogenous envelope proteins in human cancer cells was found to be unsatisfactory. Recently, several research groups have demonstrated the feasibility of a retroviral vector pseudotyped with a vesicular stomatitis virus G (VSV-G) protein. In this study, the potential of VSV-G pseudotyped MLV-based retrovirus was examined as a delivery vehicle in a variety of human cancer cells including brain tumor cells in vitro and in vivo. The transduction efficiency of the 293T/G/GP/LacZ retrovirus in cell culture was superior in most cancer cells, particularly in brain tumor cells, compared with that of other retroviruses, such as PA317- or PG13-derived. The relative growth rate and phosphatidylserine expression level on the plasma membrane of target cells mainly influenced the transduction efficiency of VSV-G pseudotyped retrovirus, which suggested that both the relative growth rate and phosphatidylserine expression level were major determinants of TE. Furthermore, 293T/G/GP/LacZ could efficiently transduce human cancer cells regardless of the presence of chemical additives, whereas in other retroviruses, cationic chemical additives such as polybrene or liposomes were essential during virus infection. Finally, an average of 10% gene expression was routinely obtained exclusively in the tumor mass when 293T/G/GP/LacZ concentrated by simple ultracentrifugation was directly administrated to pre-established brain tumors in animal models (U251-N nu/nu mice or C6 Wistar rats). All told, the present study suggests that the VSV-G pseudotyped retrovirus is a suitable vector for brain tumor gene therapy.