Biomedical subjects
Publications and source records attributed to K Fujii.
A multiplex typing method of the tetrameric short tandem repeat (STR) loci TH11, D9S304, and D3S1744 was developed. The allelic ladder included alleles 6-11 (80-100bp) and 9.3 (95bp) for TH01, alleles 6-15 (125-161 bp) for D9S304, and alleles 13-22 (174-210bp) for D3S1744. The observed heterozygosity of D9S304 was 0.851. The combined discrimination power of the three loci was 0.991.
OBJECTIVES: The present investigation was undertaken to determine the reinforcing effect of woven glass fibers on deflection, flexural strength, flexural modulus and impact strength of acrylic denture base polymer. METHODS: Three silanized or unsilanized woven glass fibers were used. Specimens were made by heating the denture cure resin dough containing glass fibers, which were sheathed in the dough. Specimens with four different thicknesses and of five different types were made, incorporating the glass fiber. Three-point flexural test and flywheel type impact test were employed to determine the flexural properties and impact strength. RESULTS: When specimens contained unsilanized glass fiber, the flexural strength in specimens of 1 and 2 mm thickness and the impact strength in specimens of 2 mm thickness were higher than those of specimens without glass fiber (p < 0.01). On the contrary, the flexural strength and deflection in specimens reinforced with silanized glass fiber of 1 mm thickness were significantly higher (p < 0.01, p < 0.05) than those of unreinforced specimens. Further, the impact strength in specimens reinforced with silanized glass fiber of 2 mm thickness was significantly higher (p < 0.01) than that of unreinforced specimens. Statistically significant differences were found in the flexural strength (p < 0.05) and in the impact strength (p < 0.01) when specimens of 4 mm thickness were reinforced with two or three unsilanized glass fibers. SIGNIFICANCE: The reinforcement with glass fiber was effective in thin specimens, and the reinforcing effect increased with the increase of the number of glass fibers in the case of thick specimens.
BACKGROUND: Although some previous research has focused on the relationship between panic disorder (PD) and a high total cholesterol (TC) level, it is still controversial. Recently, researchers have reported the heterogeneity of clinical symptoms in PD and the complexity of the correlations found among them. Therefore, the controversy on the TC level in PD may be due to the existence of clinical subgroups in PD. It is important to ascertain whether or not an elevated TC level in patients with PD is associated with specific panic symptoms. METHODS: In 104 drug-free patients with PD, we examined the relationship between TC level and each of several panic symptoms occurring at the time of panic attacks (PAs), which included anticipatory anxiety, agoraphobia, and 13 panic symptoms based on the DSM-III-R. RESULTS: Stepwise regression analysis revealed a significant effect of the presence of the symptom 'fear of dying' on TC levels. Patients with a fear of dying had a significantly higher TC level than those without it. LIMITATIONS: The relatively small sample size may limit the generalizability of our findings. DISCUSSION: These data suggest that TC level may be associated with panic symptoms in patients with PD.
The effects of adrenomedullin (AM) and proadrenomedullin N-terminal 20 peptide (PAMP) on membrane potential and sympathetic neurotransmission were studied in rat mesenteric arteries by using microelectrodes. AM (10(-7) M) but not PAMP (10(-6) M) produced membrane hyperpolarization, which was abolished by high K solution or by glibenclamide, an ATP-sensitive K(+) (KATP) channel blocker. Neither AM nor PAMP affected excitatory junction potentials, a measure of sympathetic, purinergic neurotransmission. These findings suggest that AM hyperpolarizes the membrane via activation of KATP channels, which may contribute to the vasodilatory action of AM, whereas the mechanisms of the vasodepressor action of PAMP remain unclear.
We reported the magnetic resonance imaging of four young patients (13 to 19 years) with nevoid basal cell carcinoma syndrome (NBCCS), which showed empty sella, agenesis of the corpus callosum and empty sella, an interhemispheric lipoma with callosal dysgenesis, and an arachnoid cyst in the posterior fossa, respectively. Calcification of the diaphragma sellae, which is a protective barrier against the pulsating action of the cerebrospinal fluid, may cause the empty sella in NBCCS.
A rare case of persistent hypoglossal artery in conjunction with arteriovenous malformation was presented. MRA could delineate persistent hypoglossal artery and arteriovenous malformation very clearly. The patient suffered from intracranial hemorrhage from in the 37th week of pregnancy. MRI, MRA, angiography, and CT of this rare condition are reported.
The effect of osmotic stabilizers on protoplast formation of yellow/white color mutants of Chlorella ellipsoidea was studied. The UF-1 strain, one of the mutants, had the same growth rate as the parent C. ellipsoidea at 4.02 microE/m2/s and no reversion to normal cells at 0-26.8 microE/m2/s. Therefore, protoplast formation from UF-1 was carried out, and it was found that the yield of protoplasts was 93% in the medium containing 1.0 M NaCl as an osmotic stabilizer.
New adjuvant therapy individualized by the results of reverse transcription-polymerase chain reaction (RT-PCR) for drug-resistance genes has been used to treat malignant gliomas. Protocol studies for malignant gliomas were not so encouraging in their therapeutic results because of heterogeneity and the various drug-sensitivities of the tumors. Individualization of glioma therapy is recommended. Drug-resistance genes messenger ribonucleic acid (mRNA) expressions were investigated in drug-resistant human glioma cell lines derived from U87MG and 46 frozen samples of retrospectively examined neuroepithelial tumors (12 low grade neuroepithelial tumors, 16 Grade III gliomas, 11 glioblastomas, and 7 other malignant neuroepithelial tumors such as medulloblastomas and primitive neuroectodermal tumors) by RT-PCR with the specific primers for O6-methylguanine DNA methyltransferase (MGMT), multidrug-resistance gene 1 (MDR1), multidrug-resistance-associated protein (MRP), and glutathione-S-transferase-pi (GST-pi). Thirty-seven preliminary individual adjuvant therapies (IAT) based on RT-PCR results, mainly in MGMT expression, were performed on 30 consecutive patients with neuroepithelial tumors. In the retrospectively examined series, the initial response to 1-(4-amino-2-methyl-5-pyrimidynyl) methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) was correlated most significantly to the MGMT mRNA expression among 11 independent prognostic factors (p = 0.0037) in multivariate logistic regression analysis. In the preliminary IAT, 17 of 32 evaluable therapies had a partial or complete response (53.1% response rate). Our IAT based on RT-PCR seemed to be more effective than conventional therapies for malignant gliomas.
The direct effects of the nucleoside transporter inhibitor dilazep on the cell cycle of mesangial cells have not before been investigated. The purpose of this study was to elucidate whether dilazep can inhibit the proliferation of mesangial cells and how it interferes with the cell cycle of these cells. DNA histograms were used and BrdUrd uptake rate was measured by flow cytometry. There was no significant difference in the cell numbers among the untreated group and the 10(-5) M, 10(-6) M or 10(-7) M dilazep-treated groups at 24 h of incubation. However, at 48 and 72 h, the cell numbers in the dilazep-treated groups were significantly lower compared with that of the untreated group (P < 0.005). The DNA histograms of cultured rat mesangial cells at 12, 24, and 48 h of incubation with 10(-5) M dilazep showed that the ratio of the S phase population in the dilazep-treated group decreased by 2.2% at 12 h, by 9.6% at 24 h, and by 18.9% at 48 h compared with the untreated group. The ratio of the G0/G1 phase population in the dilazep-treated group significantly increased: 6.8% at 12h (P < 0.05), 13.9% at 24 h (P < 0.001), and 76.5% at 48 h (P < 0.001) compared with the untreated group. A flow cytometric measurement of bivariate DNA/BrdUrd distribution demonstrated that the DNA synthesis rate in the S phase decreased after 6 h (P < 0.005) and 12 h (P < 0.05) of incubation compared with the untreated group. These results suggest that dilazep inhibits the proliferation of cultured rat mesangial cells by suppressing the G1/S transition by prolonging G2/M and through decreasing the DNA synthesis rate.
The viscoelastic properties of denture base polymers, such as poly(methylmethacrylate) (PMMA), polycarbonate (PC), polysulfone (PSF) and polyethersulfone (PES) which have been used in current clinical dentistry were investigated. In addition, water absorption, diffusion coefficient of water into material, cubical expansion, specific volume and residual monomer were also determined. From the results of this study, the viscoelastic behaviours of the denture base polymers in water have been discussed. The relaxation modulus (Er(5)) which was calculated using a stress at 5 s from the start of measurement for the specimen which reached an equilibrium moisture content (wet specimen), decreased from 23.1 to 25.5% compared with that of PMMA stored in a desiccator (37 degrees C) for 1 week (dry specimen). In contrast, this decreasing ratio was 7.0 to 10.0% for PC, PSF and PES. It is suggested that this phenomenon is caused by the increase of specific volume (cm3/g) with water absorption in each material. The water absorption of the PMMA group was relatively large in comparison with other material and was 1.81-1.85%. This value was within the range from 0.38 to 1.74% for PC, PSF and PES. The diffusion coefficients of water for PC, PSF and PES increased by approximately 1.5-2.7 times that of PMMA. Furthermore, the coefficient of cubical expansion of the wet specimen was larger than that of the dry specimen. The increasing ratio was 1.03-1.10 times for the PMMA group and 1. 18-2.38 times for PC, PSF and PES. The variation of Er(5) of the PMMA group with temperature in water was larger than those of PC, PSF and PES.
As a member of the alpha-amylase superfamily of enzymes, amylomaltase catalyzes either the transglycosylation from one alpha-1,4 glucan to another or an intramolecular cyclization. The latter reaction is typical for cyclodextrin glucanotransferases. In contrast to these enzymes, amylomaltase catalyzes the formation of cyclic glucans with a degree of polymerization larger than 22. To characterize the factors that determine the size of the synthesized cycloamyloses, we have analyzed the X-ray structure of amylomaltase from Thermus aquaticus in complex with the inhibitor acarbose, a maltotetraose derivative, at 1.9 A resolution. Two acarbose molecules are bound to the enzyme, one in the active site groove at subsite -3 to +1 and a second one approximately 14 A away from the nonreducing end of the acarbose bound to the catalytic site. The inhibitor bound to the catalytic site occupies subsites -3 to +1. Unlike the situation in other enzymes of the alpha-amylase family, the inhibitor is not processed and the inhibitory cyclitol ring of acarbose, which mimicks the half chair conformation of the transition state, does not bind to catalytic subsite -1. The minimum ring size of cycloamyloses produced by this enzyme is proposed to be determined by the distance of the specific substrate binding sites at the active site and near Tyr54 and by the size of the 460s loop. The 250s loop might be involved in binding of the substrate at the reducing end of the scissile bond.
The possible relationship between deep white matter hyperintensity (WMHI) lesions detected by magnetic resonance imaging and response to lithium was examined in 16 patients with bipolar disorder who had been under maintenance treatment with lithium for more than 1 year. Bipolar patients who had higher scores of WMHI responded significantly better to lithium (r = 0.57, P < 0.05) than did those who had lower scores. This preliminary result suggests that the presence of WMHI may be associated with a better response to lithium.
Cerebral arteriovenous malformations (AVMs) are classified angiographically into two types: the arteriovenous fistula (AVF) type and the plexiform type. However, the differences in vascular structure of these two types have not been clarified. The purpose of the present study is to elucidate the vascular structure of plexiform AVMs and to discuss the clinical significance of this classification of AVMs. Specimens of AVMs resected in 8 cases and identified by cerebral angiography as plexiform AVMs were examined. Immediately after their removal, microdissection of the terminal arterial feeder, the nidus, and the venous drainer was performed under a microscope. A histological examination of each element was then conducted. Microdissection of a portion of the vascular mass that formed the nidus made it possible to separate individual vessels of the mass from each other. Many of these individual vessels connected with the feeder on one side, while the other side anastomosed with the drainer, thus exhibiting the morphology of an AVF. From our examination of the AVMs in the present study, we inferred that the plexiform type is fundamentally a conglomeration of AVFs. It is therefore suggested that the vascular structure of this type of AVM is not fundamentally different from that of the AVF type.
The authors review their experience with 19 consecutive cases with either astrocytic tumour (glioblastoma multiforme one, anaplastic astrocytoma one, astrocytoma 4, pilocytic astrocytoma 4) or ependymoma (10 tumours in 9 patients) of the spinal cord who were treated during the period from 1982 to 1996. The patients included 10 male and 9 female patients with a median age of 38 years. The main tumour locations included the cervicomedullary region 5 the cervical cord (8), the thoracic cord (5) and one each in the thoracolumbar region and conus medullaris. While a total removal of the tumour was achieved in 8 out of 10 ependymomas, the initial treatment for astrocytic tumours was a partial resection in 5, and biopsy in the remaining 5. As adjuvant treatment, 8 patients received radiation therapy and 2 received chemotherapy. Two patients with an astrocytic tumour received chemotherapy only, while the remaining 9 received neither radiation therapy nor chemotherapy initially. After these treatments, 6 out of the 8 patients with low grade astrocytoma have remained alive for 1.3-12.6 years, while 2 patients with high grade astrocytic tumours died within 15 months following surgery. Eight out of 9 patients with an ependymoma have remained alive for 3.0-12.3 years, while one committed suicide 2 years after surgery. As a result, 14 patients are still alive; half of them are accompanied by a mild neurological dysfunction, while the remaining one has a moderate deficit. The postoperative results and the rationale for surgery is discussed, and an approach for utilising adjuvant therapy for high grade tumours is also suggested.
Only limited information is available concerning dural arteriovenous malformations (AVMs) found in association with cerebral aneurysms. The present report focuses on six such cases, concentrating attention on clinical characteristics and significance. Of a total of 46 dural AVMs encountered over a given period, six (13%) were linked with cerebral aneurysms. Particularly strong associations were noted for dural AVMs in the anterior cranial fossa (three of four cases) and convexity (all of three cases). With dural AVMs in the anterior cranial fossa, subarachnoid haemorrhage is common, so that where this is encountered the possibility of a complicating aneurysm should be considered in order to select an appropriate treatment.
Child patients with Moyamoya disease initially present with ischemic symptoms. However, the long-term risk of intracranial hemorrhage for childhood Moyamoya disease is unknown. Hemodynamic overload to the fragile collateral vessels has been considered to cause hemorrhage. We reviewed angiograms to evaluate the effect of encephalo-myo-synangiosis (EMS) on abnormally dilated collateral vessels in 13 child patients with Moyamoya disease. EMS was performed on 24 sides in 13 patients ranging from 5 to 14 years of age. Post-operative angiography (6-88 months after surgery) revealed good revascularizations through EMS (larger than one-third of the middle cerebral artery (MCA) distribution) in 18 sides (75%) and smaller revascularizations in 6 sides (25%). In cases with a good revascularization through EMS, reduction of the abnormal collateral vessels was observed not only in the basal Moyamoya vessels (94% of sides) but also in the medullary arteries derived from the choroidal arteries (62% of sides), which are considered to cause intraventricular hemorrhages in adult patients. It is suggested that EMS may reduce the hemodynamic load on dilated collateral vessels and, subsequently, the long-term risk of intracranial hemorrhage in childhood Moyamoya disease.
Neuronal neoplasms of the CNS constitute a rarely encountered group of tumors. This report concerns the surgical management of seizures encountered in four cases (ranging from 2 to 10 years-of-age at onset; consisting of two males and two females) of a recently recognized morphologically unique tumor, called 'cerebral neurocytoma'. All patients were associated solely with intractable complex partial seizures. The tumor involved the temporal lobe in two cases, and the frontal in two. Magnetoencephalography (MEG) clearly demonstrated an accumulation of equivalent current dipoles originating from the interictal spikes on the cortex around the tumor. On intra-operative electrocorticography (ECoG), the epileptogenic zone was topographically distinct from the region of the tumor. No definite ECoG activities were observed at the tumor site, although this tumor did consist of small mature neuronal cells. Either a complete or a subtotal resection of the tumor and the epileptogenic cortex was performed and, post-operatively, universal freedom from seizures was demonstrated in all patients. A histological examination of the epileptogenic cortex revealed the presence of minute cortical dysplasia or tumor involvement in the hippocampus. A resection of the epileptogenic cortex along with the tumor was thus found to improve the seizure outcome in patients with neurocytoma-associated epilepsy without inducing any identifiable neurological deficits attributable to the incremental resection.
The peptide synthetase gene operon, which consists of mcyA, mcyB, and mcyC, for the activation and incorporation of the five amino acid constituents of microcystin has been identified [T. Nishizawa et al. (1999) J. Biochem. 126, 520-529]. By sequencing an additional 34 kb of DNA from microcystin-producing Microcystis aeruginosa K-139, we identified the residual microcystin synthetase gene operon, which consists of mcyD, mcyE, mcyF, and mcyG, in the opposite orientation to the mcyABC operon. McyD consisted of two polyketide synthase modules, and McyE contained a polyketide synthase module at the N-terminus and a peptide synthetase module at the C-terminus. McyF was found to exhibit similarity to amino acid racemase. McyG consisted of a peptide synthetase module at the N-terminus and a polyketide synthase at the C-terminus. The microcystin synthetase gene cluster was conserved in another microcystin-producing strain, Microcystis sp. S-70, which produces Microcystin-LR, -RR, and -YR. Insertional mutagenesis of mcyA, mcyD, or mcyE in Microcystis sp. S-70 abolished microcystin production. In conclusion, the mcyDEFG operon is presumed to be responsible for 3-amino-9-methoxy-2,6, 8-trimethyl-10-phenyldeca-4,6-dienoic acid (Adda) biosynthesis, and the incorporation of Adda and glutamic acid into the microcystin molecule.