Dehydroepiandrosterone inhibits the death of immunostimulated rat C6 glioma cells deprived of glucose.

Pretreatment of interferon-gamma and lipopolysaccharides made C6 glioma cells highly vulnerable to glucose deprivation. Neither 12 h of glucose deprivation nor 2-day treatment with interferon-gamma (100 U/ml) and lipopolysaccharides (1 microg/ml) altered the viability of C6 glioma cells. However, significant death of immunostimulated C6 glioma cells was observed after 5 h of glucose deprivation. The augmented death was prevented by dehydroepiandrosterone (DHEA) treatment during immunostimulation, but not by DHEA treatment during glucose deprivation. DHEA reduced the rise in nitrotyrosine immunoreactivity, a marker of peroxynitrite, and superoxide production in glucose-deprived immunostimulated C6 glioma cells. DHEA, however, did not protect glucose-deprived C6 glioma cells from the exogenously produced peroxynitrite by 3-morpholinosydnonimine. Further, DHEA did not alter the production of total reactive oxygen species and nitric oxide in immunostimulated C6 glioma cells. Superoxide dismutase (SOD) and the synthetic SOD mimetic Mn(III)tetrakis (4-benzoic acid) porphyrin inhibited the death of glucose-deprived immunostimulated C6 glioma cells. In addition, a superoxide anion generator paraquat reversed the protective effect of DHEA on the augmented death. The data indicate that DHEA prevents the glucose deprivation-evoked augmented death by inhibiting the production of superoxide anion in immunostimulated C6 glioma cells.

Augmented death in immunostimulated astrocytes deprived of glucose: inhibition by an iron porphyrin FeTMPyP.

The present study shows that under glucose-deprived conditions immunostimulated astrocytes rapidly undergo death due to their increased susceptibility to endogenously produced peroxynitrite. Fe(III)tetrakis(N-methyl-4'-pyridyl)porphyrin (FeTMPyP), but not the structurally related compounds ZnTMPyP and H(2)TMPyP, prevented the death in glucose-deprived immunostimulated astrocytes. Consistently, FeTMPyP, not ZnTMPyP and H(2)TMPyP, completely blocked the elevation of nitrotyrosine immunoreactivity (a marker of peroxynitrite) and the depolarization of the mitochondrial transmembrane potential in glucose-deprived immunostimulated astrocytes. The present data suggest that peroxynitrite may be associated with glial cell death during metabolic deterioration in the cerebral ischemic penumbra.

Regional cerebral blood flow changes in patients with intractable obsessive compulsive disorders treated by limbic leukotomy.

The object of this study is to assess the changes in regional cerebral blood flow (rCBF) following stereotactic limbic leukotomy in patients with medically intractable Obsessive-Compulsive Disorder (OCD). Technetium-99-Hexa Methyl Propylene Amine Oxime (99mTc-HMPAO) Single Photon Emission Computed Tomography (SPECT) data obtained before and after limbic leukotomy were subjected to image fusion with MRI images. Eight samples were obtained from healthy voluteers. After localization of the ROI (Region Of Interest) in anatomical area, rCBF measurements were obtained by METLAB. The results of this study show a change of rCBF following limbic leukotomy in intractable OCD. Postoperative 99mTc-HMPAO SPECT findings implicate the medial frontal cortex, cingulate and striatum, which culd be linked to limbic leukotomy that blocks the functional connection of corticolimbic loop.

Cellular distribution of isozymes of protein kinase C in septal olfactory epithelium of mice.

To determine the presence of protein kinase C (PKC) isozymes in the septal olfactory epithelium of mice (mSOE), western blotting and immunohistochemistry were performed using antibodies against PKC isozymes. With the exception of PKC-betaI, all of the PKC isozymes were detected in the whole lysate of septal tissue layer and apparent molecular weights for each isoform were found. PKC-alpha, PKC-gamma and PKC-epsilon were detected in the olfactory glandular cells of the lamina propria, and PKC-betaI and PKC-betaII were located in the microvillar cells. Neither novel PKC nor atypical PKC was detected in olfactory glandular cells or microvillar cells, except for PKC-epsilon. PKC-lambda was localized in the mucous layer of the mSOE. Meanwhile, PKC-delta and PKC-xi were distributed in the receptor cells in the mSOE. These data demonstrate the isoform-specific expression of PKC in mSOE and suggest a role for the novel and atypical types of PKC in olfactory transduction.

Cloning and characterization of the 5'-flanking region for the mouse phospholipase C-delta1 gene.

To date, little is known about the molecular mechanisms controlling the regulation of phospholipase C-delta1 (PLC-delta1) gene expression. To understand the mechanisms responsible for the regulation of PLC-delta1 gene expression, the 5'-flanking region of the mouse PLC-delta1 gene was isolated from a mouse genomic DNA library. Primer extension analysis revealed that there is a single transcriptional start site located at 127 bases upstream from the translation start codon in the mouse PLC-delta1 gene. DNA sequence analysis showed that the sequence around the transcriptional start site is very GC-rich and has no TATA or CAAT boxes. Transient expression of a luciferase reporter gene under the control of serially deleted 5'-flanking sequences revealed that the 160-base-pair region from -622 to -462 upstream of the transcriptional start site includes a positive cis-acting element(s) for the efficient expression of the PLC-delta1 gene. Gel retardation analysis suggests that multiple transcription factors bind to separate sites on the promoter region. Based on these results, our study suggests that the minimal essential region located at -622 to +70 is fully sufficient to confer high-level transcriptional activity and contains high-affinity binding elements for multiple transcription factors.

Effect of norepinephrine release on adrenoceptors in severe seizure genetically epilepsy-prone rats.

The genetically epilepsy-prone rat (GEPR) seizure model is characterized by extensive abnormalities in brain noradrenergic function. Earlier studies had suggested that GEPRs might not regulate adrenoceptors in a normal fashion. The purpose of the present study was to determine if GEPR-9s are capable of up and down regulation of alpha(1)- and beta-adrenoceptors in response to increments or decrements in extracellular norepinephrine. Seizure induction has been shown to increase extracellular norepinephrine. Chronic sound or electroshock-induced seizures caused down regulation of beta-adrenoceptors in frontal cortex and in hippocampus from GEPR-9s. Similarly, chronic daily treatment with the norepinephrine reuptake inhibitor desmethylimipramine produced down regulation of beta-adrenoceptors in frontal cortex and in hippocampus from GEPR-9s. As is the case in neurologically normal animals, chronic electroshock-induced seizure did not cause down regulation of beta-adrenoceptors in 6-hydroxydopamine pretreated GEPR-9s. Chronic electroshock treatment also caused up-regulation of alpha(1)-adrenoceptors in frontal cortex but not in hippocampus. In 6-hydroxydopamine pretreated GEPR-9s, chronic electroshock treatment caused a further up-regulation of alpha(1)-adrenoceptors in frontal cortex but not in hippocampus. Taken together, these results indicate that GEPR-9s are capable of up and down regulation of alpha(1)- and beta-adrenoceptors in a manner that is qualitatively similar to the regulation of these receptors in normal animals. Whether the regulation of brain adrenoceptors is quantitatively different in GEPRs from normal animals remains to be established.

An improved linkage map of rat chromosome 3 with three mapping panels.

Our purposes were to develop an improved linkage map for rat Chromosome 3 and to develop new markers polymorphic between Dahl salt-sensitive (S) and Dahl salt-resistant (R) rats. The linkage mapping panel consisted of three F2 populations totaling 359 rats. Twenty-five new markers were developed and placed on the linkage map. About half of these markers (13) were polymorphic between S and R rats. The final map spans 124.7 centiMorgans (cM) and includes 64 markers. The average distance between adjacent markers is 1.9 cM, and the largest separation is 10.5 cM.

Hereditary protein C deficiency with recurrent thrombosis: identification of a missense mutation (C6218T).

Protein C is the central component of a major anti-thrombotic regulatory system and individuals with hereditary protein C deficiency (PCD) tend to have an increased risk of thromboembolism. During the last several years, mutations causing PCD have been identified in Western countries and in Japanese. In the present study, we report a case of hereditary PCD with a missense mutation (C6218T) in a 44 year old female with recurrent pulmonary thromboembolism. The protein C activity (35%) and antigen (58%) levels in this patient were decreased. Furthermore, we have identified the same molecular defect and PCD in other asymptomatic family members including proband's mother and two daughters and one son. To our knowledge, this is the first case of hereditary PCD with identified genetic defect in the Korean population, which may be one of hot spots for mutation in the protein C gene.

Effect of pH on drug release from polysaccharide tablets.

Controlled release formations of drugs were prepared with matrix materials of the natural polysaccharides sodium alginate and +/--carrageenan. The drugs used were sodium salicylate (anionic) and lidocaine-HCl (cationic). The release characteristics of the drugs were studied under different pH and compositions of aqueous media. The cationic drug (lidocaine-HCl) was released more slowly than the anionic one (sodium salicylate) because of the negative charge of the matrices. The release from both sodium alginate and +/--carrageenan tablet was retarded in acidic medium. At the same pH of the medium, the release into buffer solutions (containing metallic cations Na(+) and K(+), respectively) was slower than into HC1 solution.

Linkage map and congenic strains to localize blood pressure QTL on rat chromosome 10.

Our purposes were to develop a linkage map for rat Chromosome (Chr) 10, using chromosome-sorted DNA, and to construct congenic strains to localize blood pressure quantitative trait loci (QTL) on Chr 10 with the map. The linkage mapping panel consisted of three F2 populations totaling 418 rats. Thirty-two new and 29 known microsatellite markers were placed on the map, which spanned 88.9 centiMorgans (cM). The average distance between markers was 1.46 cM. No markers were separated by more than 6.8 cM. Four congenic strains were constructed by introgressing various segments of Chr 10 from the Milan normotensive strain (MNS) onto the background of the Dahl salt-sensitive (S) strain. A blood pressure QTL with a strong effect on blood pressure (35-42 mm Hg) when expressed on the S background was localized to a 31-cM region between D10Mco6 and D10Mcol. The region does not include the locus for inducible nitric oxide synthase (Nos2), which had been considered to be a candidate locus for the QTL.

Simple bone cyst of the axis.

A 12-year-old girl presented with a 1-month history of posterior neck pain and a large cyst in the second cervical vertebra. She underwent complete curettage of the cyst wall without any kind of bone graft, and the surgical result was good. Microscopic findings in the cyst wall were consistent with simple bone cyst, which is very rare in the spine.

Association of Br polymorphism of platelet GP Ia gene and immune thrombocytopenic purpura.

Studies on the molecular structure underlying Br(a)/Br(b) (HPA-5) platelet alloantigen show that a single base polymorphism at position 1648 on platelet mRNA coding for GP Ia results in a amino acid substitution at position 505 on the mature GP Ia which is associated with the two serologically defined Br types. While this polymorphism has no known effects on platelet function, the possible influence of this polymorphism in immune thrombocytopenia ITP is again unexplored. Therefore, the genotype frequency of Br polymorphism in ITP was compared with that of healthy general Korean population. Interestingly, there was a statistical difference (P=0.03) in genotype frequency of Br polymorphism. The association of Br(a)/Br(b) (HPA-5)genotype and occurrence of ITP may suggest the possible influence of genetic polymorphism on the pathogenesis of ITP.

Do N-methyl-D-aspartate antagonists have disproportionately greater effects on brain swelling than on ischemic damage in focal cerebral infarction?

Using a frozen section technique, we have assessed the effects of N-methyl-D-aspartate (NMDA) antagonist upon brain swelling caused by ischemic brain edema in a rat model of focal cerebral infarction. Although pretreatment with the competitive NMDA antagonist, D-CPPene or the noncompetitive NMDA antagonist, CNS 1102 reduced both the volumes of infarction and ischemic edema in the cerebral hemisphere, mean reduction in brain edema was proportionately similar to decrease in infarct volume in the same animals (correlation coefficient, r = 0.82, p < 0.001). There was, therefore, no evidence of disproportionately greater effects with NMDA antagonist upon brain edema.

Spontaneous evolution of posttraumatic subdural hygroma into chronic subdural haematoma.

Thirteen of 145 patients with post-traumatic subdural hygroma (SDHy) developed chronic subdural haematoma (CSDH) at the involved site over a period of 6 years. CSDHs were found at the site of SDHys with no history of further head injury at a mean interval of 56 days. It appeared that these 13 patients did not have any distinguishing clinical features early on. Old age and brain atrophy on CT scans do not seem to be reasonable causative factors in the evolution of SDHy into CSDH. Initial enlargement of subdural accumulations at an early stage of SDHy and a subsequent increase in density at a later stage may point to the development of CSDH from SDHy in some instances. Ten of these 13 CSDH cases underwent surgical drainage, and the remaining 3 cases received no specific management. All resolved completely. The prognosis was good in all patients. The possible mechanism for the evolution of SDHy into CSDH is discussed.

Pretreatment with a competitive NMDA antagonist D-CPPene attenuates focal cerebral infarction and brain swelling in awake rats.

The purpose of the study was to assess effects of the competitive N-methyl-D-aspartate (NMDA) receptor antagonist D-(E)-4-(3-phosphonoprop-2-enyl)piperazine-2-carboxylic acid (D-CPPene) upon focal cerebral infarction and brain oedema in the rat. Focal cerebral ischaemia was produced by permanent occlusion of the middle cerebral artery under halothane anaesthesia. The anaesthetic gas was discontinued immediately after the occlusion and the rats were killed 24 hours later. Cerebral infarction and brain swelling were each assessed on the frozen brain sections at 8 predetermined coronal planes. Pretreatment with D-CPPene (4.5 mg/kg i.v. followed by continuous infusion at 3 mg/kg/h until sacrifice) 15 minutes prior to MCA occlusion, significantly reduced the volume of infarction in the cerebral hemisphere by 29% (p < 0.05). Brain swelling, obtained by subtracting the nonischaemic hemispheric volume from the ischaemic hemispheric volume, was significantly reduced with D-CPPene treatment and the mean reduction in swelling (34% less than the controls: p < 0.001) proportionately similar to the decrease in infarct volume in the same animals. These data indicate that systemic administration of the competitive NMDA receptor antagonist D-CPPene has neuroprotective effects against ischaemic brain damage, and the reduction in brain swelling occurs in parallel with the reduction in ischaemic damage.

Efficacy of D-CPPene, a competitive N-methyl-D-aspartate antagonist in focal cerebral ischemia in the rat.

The effect of a novel and potent competitive N-methyl-D-aspartate (NMDA) antagonist D-(E)-4-(3-phosphonoprop-2-enyl)piperazine-2-carboxylic acid (D-CPPene) upon ischemic brain damage has been examined in a rat model of focal cerebral ischemia. Focal cerebral ischemia was produced by permanent occlusion of the left middle cerebral artery (MCA). The animals were sacrificed 24 h after MCA occlusion and the amount of ischemic brain damage was assessed at 8 predetermined coronal planes. Pretreatment with D-CPPene (1.5, 4.5 or 15 mg/kg, i.v.), initiated 15 min prior to MCA occlusion (followed by constant infusion at 1, 3 or 10 mg/kg/h), produced dose-dependent reductions in the volumes of infarction; the dose of 4.5 mg/kg being the most effective (reduced by 37%; P < 0.01). These results indicate that systemic administration of the competitive NMDA antagonist D-CPPene has neuroprotective effects in a model of focal cerebral ischemia and define the dose dependency of its neuroprotective effects.

Adrenal medullary transplantation for Parkinson's disease.

Autotransplantation of adrenal medullary tissue to the right caudate nucleus was performed in 8 patients (6 men and 2 women) with Parkinson's disease demonstrating mainly rigidity and bradykinesia. Their mean age was 52 years. The mean duration of Parkinson's disease was 7 years. Left adrenalectomy and open craniotomy were done to implant medullary tissue into the right caudate nucleus. The 6-month clinical findings were evaluated. 5 cases showed improvement, 2 cases remained unchanged and 1 was worse. There was no operative mortality, but 1 patient developed right frontal infarction postoperatively and 2 patients demonstrated subdural hygroma.

Intraventricular or epidural injection of morphine for severe pain.

Intraventricular or epidural injection of morphine through implantable infusion devices was used for severe pain in 50 patients with advanced cancer, arachnoiditis, or spinal injury. Intraventricular catheter was inserted for injection of morphine in 21 patients, 29 were treated through epidural infusion. For the evaluation of results the multimodal evoked potential (MEP) has been obtained before and after each treatment. 80% of the patients experienced good results. No significant side effects have been noted in patients with either epidural or intraventricular injection of morphine. These may be excellent methods for pain control in well selected patients.