Mapping replicational sites in the eucaryotic cell nucleus.

We have used fluorescent microscopy to map DNA replication sites in the interphase cell nucleus after incorporation of biotinylated dUTP into permeabilized PtK-1 kangaroo kidney or 3T3 mouse fibroblast cells. Discrete replication granules were found distributed throughout the nuclear interior and along the periphery. Three distinct patterns of replication sites in relationship to chromatin domains in the cell nucleus and the period of S phase were detected and termed type I (early to mid S), type II (mid to late S) and type III (late S). Similar patterns were seen with in vivo replicated DNA using antibodies to 5-bromodeoxyuridine. Extraction of the permeabilized cells with DNase I and 0.2 M ammonium sulfate revealed a striking maintenance of these replication granules and their distinct intranuclear arrangements with the remaining nuclear matrix structures despite the removal of greater than 90% of the total nuclear DNA. The in situ prepared nuclear matrix structures also incorporated biotinylated dUTP into replication granules that were indistinguishable from those detected within the intact nucleus.

Epidemiological study of acute encephalitis in Tottori Prefecture, Japan.

BACKGROUND AND PURPOSE: To conduct an epidemiological survey of acute encephalitis focusing on non-herpetic acute limbic encephalitis (NHALE) in Tottori Prefecture, western area of Japan. METHODS: A questionnaire survey on the annual number of patients aged 16 years or more with acute encephalitis from 2001 to 2005 was undertaken in 2006. RESULTS: During the study period, 49 patients were diagnosed with acute encephalitis. The subtype of acute encephalitis was as follows: 10 patients with herpes simplex encephalitis (HSE), 12 patients with NHALE, 4 patients with paraneoplastic encephalitis, 2 patients with encephalitis associated with collagen disease, one patient with viral encephalitis other than HSE, 20 patients with encephalitis with unknown causes. The service-based incidence rate of acute encephalitis was 19.0 per million person-years. The incidence rate of NHALE subtype was 4.7 per million person-years. CONCLUSIONS: Our epidemiological survey indicated an estimated 550 patients would develop NHALE per year in Japan, suggesting that NHALE may not be a rare disorder.

Suppression of actively induced and passively transferred experimental allergic neuritis by cyclosporin A.

The effect of cyclosporin A (CyA) on experimental allergic neuritis (EAN) was examined. CyA suppressed the development of actively induced EAN. The earlier treatment with CyA was begun, the more effective was its effect. CyA was effective even after the development of clinical signs. In actively induced EAN, cessation of CyA treatment lead to the development of EAN. However, in passively induced EAN, it did not. We could not find any differences in the distribution of infiltrating T cell subsets between the control group and the CyA-treated group.

An alternative elastase-mediated degradation of fibrinogen and fibrin observed in a patient with herpes simplex encephalitis and pneumonia.

A 74-year-old female developed pneumonia following herpes simplex encephalitis. Her white blood cell counts reached 28,400/microliters, about 90% of which consisted of granulocytes. The polymorphonuclear (PMN) elastase/alpha 1-antitrypsin complex levels increased and reached the maximum of 5,019 ng/ml, indicating the release of a large amount of elastase derived from the granulocytes. The mechanism of PMN elastase release was most likely to be granulocyte destruction associated with phagocytosis. The cleavage of fibrinogen and fibrin by PMN elastase, independent of plasmin, was indicated by the presence of the fragments in immunoprecipitated plasma from the patient corresponding to elastase-induced FDP D and DD fragments and the absence of fragments corresponding to plasmin-induced FDP D and DD fragments on SDS-PAGE. These findings suggested that the large amount of PMN elastase released from the excessive numbers of granulocytes in this patient with herpes simplex encephalitis and pneumonia, induced the cleavage of fibrinogen and fibrin without the participation of plasmin.

The CD5+ B cells and myasthenia gravis.

A high frequency of CD5+ B lymphocytes in the peripheral blood of patients with myasthenia gravis (MG) has been reported recently. These results seem to indicate an attractive linkage between CD5+ B lymphocytes and autoantibodies against Acetylcholine receptor in MG. We examined the frequency of CD5+ B cells in 20 patients with MG and 21 normal healthy controls by two-color flow cytometry. However, there were no significant differences in the percentages of CD5+ B lymphocytes between the two groups. We also examined the frequency of CD5+ B lymphocytes in the resected thymus of patients. The frequency of CD5+ B lymphocytes in the thymus was low and similar pattern to that in the peripheral blood. We checked the antibody (Ab) production against the human acetylcholine receptor in either CD5+ B or CD5- B lymphocytes using B lymphoblastoid cell line generated from the lymphocytes of 11 patients with anti-AChR Abs in the sera. Abs against the AChR in the human were mostly produced by CD5- B, not CD5+ B lymphocytes. The anti-AChR Abs (IgG) production of CD5+ B cells and CD5- B cells (mean +/- SD) were 6.8 +/- 2.4 fmol/ml and 18.5 +/- 17.6 fmol/ml, respectively. These results suggest that in MG, the frequencies of the CD5+ B lymphocytes in PBL may be genetic background and that there may be no strong linages between AChR Ab production and CD5+ B lymphocytes.

Structure and function of cerebral GABAA and GABAB receptors.

The receptor for GABA (gamma-aminobutyric acid), an inhibitory neurotransmitter in the brain, has been classified into GABAA and GABAB types. The GABAA receptor was purified by means of affinity column chromatography using benzodiazepine as an immobilized ligand. The results indicated that the GABAA receptor consists of several subunits and forms a GABA-gated Cl- channel, which is coupled with the benzodiazepine receptor. The molecular weight of the GABAA receptor complex was estimated to be approximately 300 kDa. Furthermore, cDNA cloning of GABAA receptor subunits was performed and the primary structure of these subunits was deduced. The results suggested that these subunits possess four transmembrane domains in their structure which are important for the formation of the Cl- channel. On the other hand, activation of GABAB receptors induced the inhibition of adenylyl cyclase activity and phosphatidylinositol turnover via inhibitory GTP-binding proteins such as G(i) and/or G(o). The GABAB receptor was purified using baclofen affinity and immunoaffinity column chromatographies. It was confirmed that the purified GABAB receptor protein is about 80 kDa in its molecular weight. This protein is capable of inducing the inhibition of adenylyl cyclase when it is reconstituted with G(i)/G(o) protein in the phospholipid vesicle system. Currently available data indicate that GABAA and GABAB receptors in the central nervous system are distinct not only in terms of their molecules but also their signal transduction systems. However, the primary structure and synaptic localization of GABAB receptor molecules in the brain remain to be clarified.

Ex vivo culture of isolated zebrafish whole brain.

We have succeeded in culturing whole zebrafish brains ex vivo for 1 week. While isolated cells and tissue slices have previously been employed for neurobiological studies, these techniques are limited, because while local networks may be preserved, their original context in the whole brain is lost. Culture of the whole brain would facilitate the study of cells and systems within an intact brain infrastructure. Our culture method entailed isolating the whole brain and placing it on a sterile and porous membrane, after which it was maintained with a conditioned medium in a six-well plate in a CO2 incubator at 28.5 degrees C. Whole brains cultured by this simple method were relatively unaltered in terms of their morphology, cytoarchitecture, immunohistochemistry and ability to transport horse radish peroxidase (HRP). This method of cultivation may be very useful for neurobiological research.

A novel monoclonal antibody recognizes a previously unknown subdivision of the habenulo-interpeduncular system in zebrafish.

The habenulo-interpeduncular system is an evolutionarily conserved structure found in the brain of almost all vertebrates. We prepared a monoclonal antibody (6G11) which very specifically recognizes only a part of this system. 6G11 is a monoclonal antibody prepared from a neuronal membrane protein in adult zebrafish brain. In western blot analysis of the adult zebrafish brain, the antibody recognized a 95 kDa protein, and the class of the antibody was determined to be IgM. The 6G11 antigen was not detected in zebrafish muscle, intestine, testis or ovary. A group of neurons stained by the 6G11 antibody was located in the caudomedial part of the zebrafish habenula. The 6G11-immunopositive neurons extended their axons into the fasciculus retroflexus (FR). One group of immunopositive neurons projected toward the interpeduncular nucleus (IPN), especially to the intermediate and the central subnucleus (type 1 neuron). The other group projected to the ventral midline at the level of the raphe nucleus; these axons passed ipsilaterally beside the IPN and converged in the ventral midline under the raphe nucleus (type 2 neuron). Both type 1 and type 2 fibers are relatively minor components of the FR. Little has previously been known about this topological pattern in any species. The 6G11 monoclonal antibody could be a useful tool for expanding knowledge of the habenulo-interpeduncular system.

Monoclonal antibody stains oligodendrocytes and Schwann cells in zebrafish (Danio rerio).

We prepared a monoclonal antibody that recognizes oligodendrocytes and Schwann cells in zebrafish. On immunoblots, the antibody mainly recognized three protein bands of 34 kDa in a membrane fraction from adult zebrafish brain. Medaka fish (Oryzias latipes) also possessed the same protein bands in a membrane fraction. The antibody did not stain neurons, but stained cells in fiber tracts and cranial and spinal nerves. In order to determine the nature of these cells, the staining pattern of the monoclonal antibody was compared with that of a myelin basic protein antiserum. Both antibodies stained oligodendrocytes and Schwann cells in fixed sections from the adult zebrafish. Both antigens were also co-localized in cultured glial cells. Taken together, these results indicate that the new monoclonal antibody recognizes myelinating glial cells in zebrafish and will be useful for the analysis of piscine glia.

The two-color analysis of the T-lymphocyte subsets in experimental allergic neuritis in rats.

We examined the T-cell subsets in the peripheral blood, spleen and lymph nodes during the course of experimental allergic neuritis (EAN) by using two-color analysis. In the acute phase, the percentages of CD4+ major histocompatibility complex (MHC)-II+ cells and CD8+ MHC-II+ cells in the lymph nodes of EAN rats were significantly higher than in the control rats. In the recovery phase, the percentage of CD4+ CD45RC+ cells and CD8+ CD45RC+ cells in the lymph nodes in EAN rats were significantly higher than in the control rats. However, significant changes of the T-cell subsets were not detected in either the spleen or the peripheral blood during the course of EAN. These results suggest that CD4+ MHC-II+ cells, CD8+ MHC-II+ cells, CD4+ CD45RC+ cells and CD8+ CD45RC+ cells may play a role in the course of EAN. The relationship between these double staining cells and EAN is discussed.

[Effect of folic acid for treatment of homocystinuria due to 5,10-methylenetetrahydrofolate reductase deficiency].

Deficiency of 5,10-methylenetetrahydrofolate reductase (MTHFR) leads to deficient remethylation of homocysteine and is one of the causes of homocystinuria. Only 28 patients have been reported so far. A 15-year-old boy with mild mental retardation was admitted in our hospital because of progressive difficulty in walking. He is the second child. The paternal grandparents are first cousins. On admission, clinical examination revealed mild disturbance of consciousness, left hemiparesis, truncal ataxia, pyramidal tract signs in the lower limbs and sensory disturbance in his feet. There was no marfanoid symptoms nor ectopia lentis. EEGs showed slow activity with sporadic spike and wave complexes. Peak latencies of N20 of median nerves SEPs, the third and 5th wave of ABR and P100 of VEP were delayed. The CT scan showed mild cortical atrophy and MRI revealed increased intensity on T2-weighted images in the cerebral white matter. Biochemical studies revealed homocystinuria with homocystinemia. Both plasma methionine and serum folic acid were low. Serum vitamin B12 and methylmalonic acid in urine were normal. The lymphoblastoid cell line, transformed by Epstein-Barr virus of lymphocytes of the patient, could not grow when homocysteine was substituted in the culture medium for methionine. The normal control cell line grew naturally under the same condition. A diagnosis of homocystinuria due to MTHFR deficiency was made. The patient was on various therapeutic regimens for about 70 days. Treatment with high doses of folic acid (400 mg/day) resulted in disappearance of homocysteine in plasma, remarkable decrease of homocysteine in urine and increase of methionine in plasma of the patient.(ABSTRACT TRUNCATED AT 250 WORDS)

[Intracranial multiple granuloma preceded by rheumatic disease--a case report].

In 1980, a 38-year-old man had remittent fever, swelling and arthralgia of the knee, ankle and wrist joints, as well as visual disturbance due to bilateral iritis. On his admission to our hospital, his laboratory data showed neutrophilia, normocytic normochromic anemia, hepatomegaly, hepatocellular damage, and a strongly positive RA test. All the microbiological examinations were negative. Thirty mg of prednisolone improved his symptoms and abnormal laboratory findings. Due to persistent mild arthralgia, he had continued to take 5-10 mg of prednisolone and analgesics until 1985 when he was readmitted to our hospital. In 1983, he began to complain of a steady pain around his left eye, and he sometimes had double vision. In 1985, he began to complain of decreasing left visual acuity and sensory disturbance in his left face in addition to pain in and around the eye. On his 2nd admission to our hospital, the neurological examination revealed involvement of the 2nd and 3rd cranial nerves and the 1st branch of the 5th cranial nerves of the left side. Laboratory data showed a positive RA test with RAHA titer at 1:320 and IgM at 216 mg/dl, but he had no joint deformities. The computed tomography (CT) of the brain demonstrated a high density mass of his left cavernous sinus extending to the left orbital apex. The prescription of the high dose of prednisolone (100 mg/day) relieved ophthalmic pain and improved visual acuity and neurological involvement within a week. Prednisolone was then gradually decreased to 10 mg. In 1986, he had partial and complex partial seizures.(ABSTRACT TRUNCATED AT 250 WORDS)

[A mechanism of cheiro-oral syndrome due to brainstem lesions, a case of a dissecting aneurysm of the basilar artery].

A 42-year-old woman developed an abrupt onset of severe headache, nausea, vomiting, unstable gait and numbness around the right side of her mouth and in her right hand. Neurological examination revealed bilateral pyramidal tract signs and hypesthesia of her right palmar tip and the right side of her mouth. However, pain and temperature sensibility was preserved. Cerebrospinal fluid was clear and colorless. CT scan showed an enhancing mass in the prepontine cistern compressing the pontine base. Vertebral angiography revealed irregular narrowing of bilateral vertebral arteries (string sign) proximal to a fusiform aneurysm on the entire length of the basilar artery. MRI showed double lumina in the wall of the aneurysm. The medial lemniscus conducts the discriminatory tactile and the deep sensory impulses from the extremities. The ventral ascending tract of the trigeminal nerve conducts the discriminatory tactile sensory impulses from the face. These two tracts lie close together in the pontine tegmentum, which is also a watershed area of the paramedian branches and circumferential branches of the basilar artery. We suggest that in this case the dissecting aneurysm caused ischemia of these two tracts in the left pontine tegmentum, presenting right cheiro-oral syndrome.

[Two cases of adult Down's syndrome presenting parietal low uptake in 123I-IMP-SPECT].

We performed 123I-IMP-SPECT to patients with Down's syndrome who were supposed to have neuropathological findings of dementia of the Alzheimer's type. In case 1, a 52-year-old man with dementia, bilateral posterior parietal low uptake and right temporal low uptake were noted. Uptake was markedly lower in the right hemisphere. Case 2, a 38-year-old man not exhibiting clinical features of dementia, presented slightly decreased uptake in bilateral posterior parietal areas. We conclude that the patterns of abnormally decreased uptake in these cases of Down's syndrome are similar to those in dementia of Alzheimer's type, and that there is a possibility to detect the predemented stage of Down's syndrome by 123I-IMP-SPECT.

[A case of dissecting aneurysm of the basilar artery presented as superior pons type of Foville's syndrome].

Here we report a 47-year-old man with dissecting aneurysm of the basilar artery who developed Foville's syndrome due to upper pons involvement. At first he had an abrupt onset of dysarthria and weakness in his left upper and lower extremities during his work. Neurological examination on admission revealed mild disturbance of consciousness, absent light reaction on the left side, hypesthesia of the left face, absent gag reflex, dysarthria, and left hemiparesis with ataxia. On the second hospital day he developed paralysis of conjugate eye movement to the right, left central facial palsy, and left hemiplegia, and hyperhidrosis of the left side of the body. He was diagnosed to have superior pons type of Foville's syndrome. Computed tomography showed low density area in the right upper pons, and the basilar artery had marked lateral shift, dilatation, and calcification. Vertebral angiography demonstrated dissecting aneurysm of the basilar artery. Although it is very rare that dissecting aneurysm of the basilar artery causes the brain stem symptoms, its possibility should be considered when computed tomography shows marked lateral shift, dilatation, and/or calcification of the basilar artery.

[A case of late-onset carbamoyl phosphate synthetase I deficiency, presenting periodic psychotic episodes coinciding with menstrual periods].

Carbamoyl phosphate synthetase I deficiency (CPSID) is a rare metabolic disorder affecting the first enzymatic step of urea cycle. We report clinical manifestations of a female case of late-onset CPSID in Japan. An 18-year-old girl was admitted to emergency room due to acute comatose state. Her parents had no apparent consanguineous history. She had suffered from intermittent psychotic episodes (excitation, aggressive behavior and insomnia) with nausea and vomiting from the age of 13, mostly coinciding with menstrual period. She had minor learning disability without major neurological deficits and convulsions. Her mental status was estimated as normal in her intermenstrual period. She had been diagnosed as having hysteria and premenstrual syndrome. Her neurological findings on admission showed deep coma and hypotonic tetraparesis. Plasma ammonia level was markedly elevated (684 micrograms/dl) without significant liver dysfunction. Blood urea nitrogen decreased to 6 mg/dl. Continuous venovenous filtration with subsequential administration of sodium benzoate and l-arginine was started to eliminate blood ammonia. Although the plasma ammonia level decreased to 300 mu/dl in next 10 hours, severe cerebral edema was observed in head computed tomography subsequently, followed by marked cerebral atrophy. Finally, her consciousness status became almost alert a month after the onset, but her mental status was severely retarded. CPSI activity of her biopsied liver markedly decreased and she was diagnosed as having CPS ID. CPSI cDNA analysis of her biopsied liver demonstrated a V1149G mutation. Genomic DNA analysis showed that she was heterozygous in V1149G mutation. The mutation allele was derived from her father. The causative factor for absence or very low level of maternal CPSI mRNA will require further analysis.

[A case of intracranial multiple nonspecific granulomas related to rheumatic disease: with special reference to magnetic resonance imaging].

We encountered a rare case of a 48-year-old man with intracranial multiple granulomas secondarily caused by rheumatic disease. This was proven surgically after an 11-year course of remissions and deteriorations. In 1980, at the age of 32 years, the patient was first seen at the clinic of Neurology of the University Hospital, complaining of swelling and arthralgia of the joints of the knee, ankle, and wrist and with remittent fever and visual disturbance. The patient was diagnosed as having possible rheumatoid arthritis, and treated with administration of 30mg/day of prednisolone, which greatly improved the symptoms. The administration of 5 to 10mg/day of prednisolone had been continued after discharge from hospital. In 1985, visual acuity of the left eye decreased, and left facial hypesthesia developed. The patient was rehospitalized at the same clinic, and treated with 100mg/day of prednisolone, which again diminished the symptoms. Computed tomography(CT) on admission showed a high density mass with contrast enhancement in the left cavernous region. In addition to the left cavernous mass, a high density mass was detected by CT in the left parietal lobe, in 1987. Visual acuity of the left eye deteriorated in 1989. Because his response to prednisolone had decreased, the visual symptom was treated with gold sodium, which acted effectiveness. Symptoms deteriorated again in 1990. Early in 1991, CT and magnetic resonance imaging showed a new mass at the right frontal lobe, while the mass in the left cavernous region had increased in size. The patient was transferred to the clinic of Neurosurgery for surgical treatment.(ABSTRACT TRUNCATED AT 250 WORDS)