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Biomedical subjects

T Fujiwara

Publications and source records attributed to T Fujiwara.

At least 613 records · Page 34Linked to original sources
PubMed1995

Wavelength specificity of photoparoxysmal responses in idiopathic generalized epilepsy.

Using optic filters, we analyzed the wave-length specificity of photoparoxysmal responses (PPR) in photosensitive patients with idiopathic generalized epilepsy (IGE). We specified the wavelength spectrum approximately 700 nm (660-720 nm) as the only visible spectrum essential for eliciting PPR in some normal trichromat IGE patients and showed that any flashing lights containing this essential wavelength spectrum could elicit PPR independent of the number of stimulated cones. Absorption of the wavelength spectrum approximately 700 nm by optic filters eliminated PPR in normal trichromat IGE patients. In an IGE patient with deuteranomaly, intermittent flashing lights containing a part of the wavelength spectrum from 580 to 700 nm elicited PPR. These data suggest a new interpretation of wavelength specificity of PPR: Flashing lights containing the wavelength spectrum that does not produce antagonistic cone interactions at the level of retinal ganglion cells can elicit PPR in some photosensitive IGE patients.

Adolescent↗
PubMed1995

Self-induced photogenic seizures in a child with severe myoclonic epilepsy in infancy: optical investigations and treatments.

In a 2-year-old patient with severe myoclonic epilepsy in infancy, we studied self-induced photogenic seizures using optical filters and blue-tinted contact lenses. The patient induced absences and/or myoclonic jerks by two kinds of behaviors: flickering hand movement (FHM) and forced eye closure (FEC). The placebo inhibitory effect on FHM by a blank goggle frame indicated that acquisition of learning affected the frequency of FHMs per se. Optical studies suggested that the degree of absorption from approximately 600-700 nm might determine the inhibitory effect of filters on FHM. Investigations using contact lenses showed that blue-tinted lenses gradually reduced photosensitivity and inhibited FHMs.

Child, Preschool↗
PubMed1995

Nonphotosensitive video game-induced partial seizures.

We report a 9-year-old boy with a ring 20 chromosome anomaly whose complex partial seizures (CPS), presumably of frontal lobe origin, were often induced by playing video games. Neither photosensitivity nor pattern sensitivity was observed. An intensive video-EEG investigation showed that video games as well as mental calculation elicited rhythmic runs of bilateral high-voltage slow waves, which eventually evolved into ictal discharges. This case suggests that higher brain functions can be involved in seizure induction.

Brain↗
PubMed1995

Clinical, microbiological and host defense parameters associated with a case of localized prepubertal periodontitis.

A 4-year-old Japanese boy was referred to Osaka University Dental Hospital because of severe mobility and pain of the right lower primary canine. The canine had severe bone loss and a pocket depth exceeding 5-6 mm. The left lower canine showed slight mobility and moderate alveolar bone loss. The other primary teeth showed no pathogenic findings. The subgingival microflora from the right lower canine was dominated by gram-negative rods, especially capnocytophaga and fusobacterium, while actinomyces sp. were the most common gram-positive bacteria. While neutrophil functions of the patient were within the normal ranges of healthy subjects, some lymphocyte functions such as IL-2 production and IgG and IgM syntheses were lower in the patient. 7 months after the extraction of the right lower primary canine, the patient complained of pain around the right lower primary lateral incisor. In 3-4 weeks, the alveolar bone was lost rapidly and mobility of the lower anterior teeth increased significantly. The primary lateral incisor was extracted and the other primary teeth were treated by sealing and systemic and local administration of antibiotics. After treatment, the lower anterior teeth became less mobile and the gram-positive cocci predominated.

Actinomyces↗
PubMed1995

[Usefulness of endotoxin-specific limulus test for the measurement of endotoxin in cerebrospinal fluid in diagnosis of bacterial meningitis].

Using a new endotoxin-specific chromogneic limulus assay (Endoscopy test), endotoxin concentrations were measured in 93 specimens of cerebrospinal fluid (CSF) from 66 pediatric patients. Eighteen patients were diagnosed as having menigitios. Of these, 6 cases (group A) with gram-negative meningitis proven by culture had high CSF endotoxin concentrations of 115.3, (82-133) (median, range) pg/ml. Ten cases (group B) with gram-positive or aseptic meningitis had endotoxin concentrations of 2.15 (0.1-3.6) pg ml. Other 2 cases with bacterial meningitis (group C), in whom no pathogen was detected, had CSF endotoxin concentrations of more than 100 pg/ml. Four cases with encephalitis (group D) and 45 cases with non-meningitis or non- encephalitis (group E), had CSF endotoxin concentrations of less than 5 pg/ml. Despite a negative culture after antibiotic treatment in group A patients, endotoxin was cleared slowly from the CSF. A clearing of endotoxin from CSF was followed by alleviation of fever with a more gradual decline in CRP values. In 2 cases of group C, the negative bacterial culture appeared to be attributable to the previous treatment with antibiotics. However, these patients had high CSF endotoxin levels, indicating gram negative bacterial meningitis. In 17 CSF specimens from 5 patients of group A, in whom Haemophilus influenzae was detected on admission, an additional a latex agglutination test for the detection of H. influenzae polysaccharide antigen was performed. Only 3 specimens from 3 patients with CSF endotoxin concentrations of more than 80 pg/ml had a positive agglutination test. These results suggest that quantitation of endotoxin concentrations is useful for the diagnosis of gram-negative meningitis. And also, the clearance of endotoxin from CSF during treatment appears to be useful in determining the timing of when antibiotic should be stopped.

Adolescent↗
PubMed1995

Different roles of bases within the integration signal sequence of human immunodeficiency virus type 1 in vitro.

To investigate the roles of bases near the tips of each strand of the long terminal repeat of the human immunodeficiency virus type 1 in the integration reaction, we examined the efficiencies of both binding and integration activities of staggered-ended substrates and mismatched mutant substrates by the integration assay and the UV cross-linking assay. Our results suggest that some bases of the human immunodeficiency virus type 1 long terminal repeat are required primarily for binding, whereas others are more critical for later reaction steps in vitro.

Base Sequence↗
PubMed1995

Wild-type human p53 and a temperature-sensitive mutant induce Fas/APO-1 expression.

Fas/APO-1 is a cell surface protein known to trigger apoptosis upon specific antibody engagement. Because wild-type p53 can activate transcription as well as induce apoptosis, we queried whether p53 might upregulate Fas/APO-1. To explore this possibility, we examined human p53-null (H358 non-small-cell lung adenocarcinoma and K562 erythroleukemia) and wild-type p53-containing (H460 non-small-cell lung adenocarcinoma) cell lines. When H358 or H460 cells were transduced with a replication-deficient adenovirus expression construct containing the human wild-type p53 gene but not with vector alone, a marked upregulation (approximately a three-to fourfold increase) of cell surface Fas/APO-1 was observed by flow cytometry. Similarly, K562, cells stably transfected with a plasmid vector containing the temperature-sensitive human p53 mutant Ala-143 demonstrated a four- to sixfold upregulation of Fas/APO-1 by flow-cytometric analysis at the permissive temperature of 32.5 degrees C. Temperature-sensitive upregulation of Fas/APO-1 in K562 Ala-143 cells was verified by immunoprecipitation and demonstrated to result from enhanced mRNA production by nuclear run-on and Northern (RNA) analyses. Stably transfected K562 cells expressing temperature-insensitive, transcriptionally inactive p53 mutants (His-175, Trp-248, His-273, or Gly-281) failed to upregulate Fas/APO-1 at either 32.5 degrees or 37.5 degrees C. The temperature-sensitive transcription of Fas/APO-1 occurred in the presence of cycloheximide, indicating that de novo protein synthesis was not required and suggested a direct involvement of p53. Collectively, these observations argue that Fas/APO-1 is a target gene for transcriptional activation by p53.

Adenocarcinoma↗
PubMed1995

Types of collagen synthesised by the lens epithelial cells of human cataracts.

AIMS/BACKGROUND: Residual lens epithelial cells (LECs) undergo fibrous proliferation after cataract surgery, resulting in capsular fibrosis. The purpose of this study was to determine the types of collagen produced in cultured LECs derived from human cataract LECs. METHODS: A circular section of the anterior capsule, about 5 mm in diameter, with LECs attached was obtained by anterior capsulotomy during cataract surgery and cultured directly without dispersion of the cells in a well, on the bottom of which a disc-shaped, thin plate of poly(methyl methacrylate) had been placed. At 5 to 6 weeks of culture, the proliferated cells of the culture were stained immunohistochemically with antibodies against human collagens I-VI by the avidin-biotin-peroxidase complex method. RESULTS: Collagens I, IV, V, and VI were positive in the cultured cells. Types IV and V were strongly present in almost all the cells whereas types I and VI were only observed in a few cells. Collagens II and III were negative. CONCLUSIONS: Since the lens capsule is known to be comprised of collagen IV, collagens I, V, and VI seem to be produced newly in culture. The capsular fibrosis seen after cataract surgery in vivo as a wound healing process of the lens capsule, may contain these types of collagens. The present culture model is useful for studying secondary cataract formation.

Cataract↗
PubMed1995

Location of focal silver staining at endothelial gaps in inflamed venules examined by scanning electron microscopy.

The century-old histological technique of silver nitrate staining has proven to be extremely useful for visualizing endothelial cell borders and localizing endothelial gaps, but the significance of the staining is still not fully understood. To gain some insight into what silver nitrate stains, we developed a method that enabled us to use scanning electron microscopy with backscattered and secondary electron imaging to examine silver staining at endothelial cell borders of venules of the rat tracheal mucosa. We found that in normal venules, silver lines followed the smooth contour of cell borders. However, 1 min after endothelial permeability was increased by substance P, cell borders were irregular and displaced from the silver lines by as much as 4.3 microns, and the lines were accompanied by three types of silver deposits. Most common (46% of total) were annulus-shaped silver deposits that surrounded endothelial gaps. These deposits averaged 1.5 microns in width, were positioned symmetrically across cell borders, and were located at a depth of 0.3 micron beneath the luminal surface. Many endothelial gaps were partitioned into multiple pores (mean, 2.4) by fingerlike processes of endothelial cells. Surprisingly, the gaps occupied only 5.4% of the total area of the silver deposits and constituted 0.15% of the luminal surface of the leaky postcapillary venules. A second type of silver deposit (19% of total) was positioned asymmetrically with respect to the cell border and marked sites where endothelial cell margins still overlapped but appeared to be vertically separated by obliquely oriented gaps. A third type marked gaps at three-cell junctions; these were no more abundant than deposits elsewhere around the cell perimeter, suggesting that three-cell junctions were not unusually leaky sites. We conclude that silver nitrate marks endothelial cell borders and outlines endothelial cell gaps by staining an element of intercellular junctions. The annular shape of many silver deposits around gaps suggests that junctional elements in the apposing cells are separated during gap formation but are still present at the gap perimeter.

Animals↗
PubMed1995

Molecular cloning, characterization, and chromosomal mapping of a novel human gene (GTF3A) that is highly homologous to Xenopus transcription factor IIIA.

We have isolated a novel human cDNA that is highly related to Xenopus transcription factor IIIA (TFIIIA). This clone contains an open reading frame of 1,269 nucleotides encoding 423 amino acids, including nine repeats of the Cys2His2-type of zinc-finger domain. A comparison of its sequence with Xenopus TFIIIA revealed 63% identity in nucleic acids and 58% identity in amino acids over a large portion of the gene and predicted peptide, indicating that the human homologue is likely to function as a transcription factor. The zinc-finger domains of the predicted protein also showed homology with those of human genes such as WT1, transcriptional repressor YY1, and MYC-associated zinc-finger protein (MAZ). Northern analysis showed expression in various tissues examined. The human TFIIIA gene (GTF3A) was localized to chromosome band 13q12.3-->q13.1 by fluorescent in situ hybridization (FISH).

Amino Acid Sequence↗
PubMed1995

Adhalin gene mutations in patients with autosomal recessive childhood onset muscular dystrophy with adhalin deficiency.

Homozygous adhalin gene mutations were found in three patients from two consanguineous families with autosomal recessive childhood onset muscular dystrophy. Muscle biopsies from patients in each family showed complete absence of adhalin. Sequencing of adhalin cDNA prepared from skeletal muscle by reverse transcription PCR demonstrated a cytosine to thymidine substitution at nt 229 in the patient in family 1 and an adenine to guanine substitution at nt 410 and a 15-base insertion between nt 408 and 409 in the two patients in family 2. Sequencing of genomic DNA prepared from peripheral blood leukocytes by PCR confirmed these mutations. The parents in each family were found to be heterozygous for the respective mutations. These adhalin gene mutations are presumed to be responsible for the absence of adhalin in the skeletal muscle. Adhalin deficiency likely causes disruption of the muscle cell membrane, resulting in dystrophic changes in the skeletal muscle similar to dystrophin deficiency in Duchenne muscular dystrophy.

Adult↗
PubMed1995

Morphological changes in human cerebral arteries after percutaneous transluminal angioplasty for vasospasm caused by subarachnoid hemorrhage.

Light and electron microscopy were used to study morphological changes in cerebral arteries after percutaneous transluminal angioplasty (PTA) for vasospasm in two patients with aneurysmal subarachnoid hemorrhage. One patient died of gastric bleeding 5 days after PTA. Postmortem examination of the inflated middle cerebral arteries revealed heterogeneously extended walls and dilated lumina. Throughout the vessel walls, the extracellular matrix, which was composed of nonmuscle components such as increased collagen, was stretched in conjunction with the medial muscle component. Also, torn and thinned areas of the wall and intramural hemorrhages were caused by overinflation. The second patient died of massive cerebral infarction caused by diffuse vasospasm 5 days after PTA. Prominent stretching of the walls at the atheromatous plaque margin in the dilated vessel was found in addition to the morphological changes observed in the first patient. These observations suggest that characteristic pathological alterations might be present in the vessel wall at the site of angioplasty. The major mechanism of the long-lasting effects of PTA seems to be the stretching and disruption of both the degenerative muscle and the proliferative nonmuscle components, mainly in the media of the vasospastic vessels.

Adult↗
PubMed1995

Growth, hemorrhage, and regression of multiple intracerebral vasoformative tumors: report of an unusual case.

A rare case of multiple hemorrhagic vascular tumors of the cerebrum and cerebellum is reported. Computed tomographic scans in a 16-year-old girl revealed multifocal brain lesions with "jewel ring"-like areas of contrast enhancement. An old hematoma cavity was found inside the surgical specimen. Histologically, it was a vascular tumor composed of anastomosing vascular channels with proliferating endothelial cells and hemorrhages at different stages. Upon further histopathological study, this lesion could not be classified as any known vascular tumor entity, although it resembled some vascular tumors, such as cavernous hemangioma and hemangioendothelioma. The patient received steroid and alpha interferon treatment. The lesions initially increased in number once, then resolved 10 months after onset. The neuroradiological and histopathological features in the present case were characteristic, and the clinical course was unusual.

Adolescent↗
PubMed1995

Maternal placenta-like endometrial hyperplasia in a beagle dog (Canine deciduoma).

Three thumb-sized segmental swellings were found in both uterine horns of a 15 month-old, non-pregnant and non-pseudopregnant female beagle dog. Histopathological examination of the uterus revealed a marked proliferation of the endometrium that was characterized by two distinct parts, an inner tightly-folded banded layer and an outer dilated spongy layer, quite similar to the maternal placenta except for the fetus and chorion in the lumen. Because the plasma level of progesterone was unusually high at autopsy, this hormonal disorder might be related to the pathogenesis of the endometrial hyperplasia in the present case.

Animals↗
PubMed1995

Human papillomavirus DNA in cell lines derived from malignancies.

The presence of high-risk types of human papillomavirus (HPV) 16, 18 and 33 in cell lines established from several malignancies including 5 of cervical cancer and 6 of head and neck cancer was studied. HPV DNA, either type 16 or 18, was detected by polymerase chain reaction, and by Southern blot hybridization in all of the cell lines derived from cervical cancers. The hybridization patterns of HPV DNA after endonuclease digestion differed among cell lines, suggesting that all of these cell lines were independent isolates. Accordingly, high-risk types of HPV DNA seem to be ubiquitous in cervical cancer. HPV DNA was not detected in the cell lines derived from head and neck cancers or from any other malignancies besides cervical cancer in this study.

Base Sequence↗
PubMed1995

Acute hyperglycemia provides an insulin-independent inducer for GLUT4 translocation in C2C12 myotubes and rat skeletal muscle.

GLUT4 translocation and activation of glucose uptake in skeletal muscle can be induced by both physiological (i.e., insulin, nerve stimulation, or exercise) and pharmacological (i.e., phorbol ester) means. Recently, we demonstrated that high glucose levels may mimic the effects of phorbol esters on protein kinase C (PKC) and insulin receptor function (J Biol Chem 269:3381-3386, 1994). In this study, we tested whether the previously described effects of phorbol esters on translocation of GLUT4 in myotubes in culture and also in rat skeletal muscle might be mimicked by glucose. We found that stimulation of C2C12 myotubes with both insulin (10(-7) mol/l, 5 min) and glucose (25 mmol/l, 10 min) induces a comparable increase of the GLUT4 content in the plasma membrane. To test whether this effect occurs in intact rat skeletal muscle as well, two different model systems were used. As an in vitro model, isolated rat hindlimbs were perfused for 80 min with medium containing 6 mmol/l glucose +/- insulin (1.6 x 10(-9) mmol/l, 40 min) or 25 mmol/l glucose. As an in vivo model, acute hyperglycemia (> 11 mmol/l glucose, 20 min) was induced in Wistar rats by intraperitoneal injection of glucose under simultaneous suppression of the endogenous insulin release by injection of somatostatin. In both models, subcellular fractions were prepared from hindlimb skeletal muscle, and plasma membranes were characterized by the enrichment of the marker enzyme alpha 1 Na(+)-K(+)-ATPase.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Characterization of a wild poliovirus type 3 isolated Japan in 1993.

A wild poliovirus type 3 was isolated from a throat swab of a patient with upper respiratory symptoms without paralysis in Shiga Prefecture, in 1993. Wild poliovirus has never been isolated in these nine years in Japan. The most recent isolation of wild poliovirus was of type 1 in 1984 from a case of encephalomyelitis in Aichi Prefecture. Antigenic and PCR-restriction fragment length polymorphism analyses revealed that the Shiga strain was non-Sabin origin. Sequence analysis of the VP1 region confirmed that the isolate was a wild poliovirus type 3. Furthermore, this isolate had higher homology to the isolates from North Vietnam than those from Pakistan or Finland, suggesting that the Shiga strain was imported from Asian area. This strain was also shown to be neurovilurent in transgenic mice carrying human poliovirus receptor gene.

Adolescent↗