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Biomedical subjects

A Tsunoda

Publications and source records attributed to A Tsunoda.

At least 55 records · Page 3Linked to original sources
PubMed1997

Influence of phylogeny on jugular fossa shape and otological disorders.

We examined the shape of the jugular fossa and its protrusion into the tympanic cavity in 51 human skulls and in 355 various monkey skulls. All human specimens had a done-shaped fossa, and the right fossa was larger than the left in 60 per cent of the specimens. Fossae protruded into the tympanic cavity in 20 per cent of these specimens. In contrast, none of the monkey specimens had a dome-shaped fossa. Some monkeys had saucer-shaped jugular fossa; the frequency of such fossa became higher as phylogeny progressed. Furthermore, the jugular fossae in monkeys did not protrude into the tympanic cavity. The shapes of both the jugular fossa and sulcus of the transverse sinus were generally symmetrical. The shape of the jugular fossa and its positional relationship to the tympanic cavity were considered from the viewpoint of the influence of phylogeny and the possible relationship to various otological problems.

Animals↗
PubMed1997

Osteopontin antisense deoxyoligonucleotides inhibit bone resorption by mouse osteoclasts in vitro.

Osteopontin (OPN) is an acidic phosphoprotein synthesized by osteoblasts and osteoclastic cells that are localized in the mineralized phase of bone matrix. OPN is thought to bind to the vitronection receptor on the osteoclast membrane and regulates bone resorption by the osteoclast. In this study, we investigated whether or not OPN can relate to osteoclast differentiation and bone resorption in a co-culture system. When C57Black/6N mouse bone marrow cells suspended on ivory slices coated with collagen were inoculated onto a MC3T3-G2/PA6 cell layer, colonies containing TRAP(+) mononuclear and multinuclear cells were formed in the presence of 1 alpha, 25-dihydroxyvitamin D3 and dexamethasone. At the end of culture period the number of TRAP(+) osteoclast-like cells were counted and the resorption pits were evaluated by reflected light microscopy. The mRNA of OPN was detected by in situ hybridization. Osteoclast-like cells expressed OPN mRNA. The addition of an OPN antisense oligomer (5' AAT CAC TGC CAA TCT CAT 3') at the start of the co-culture period decreased the number of TRAP(+) cells present after 7 d (30.3 +/- 3.4 vs 56.9 +/- 12.4), and the ratio of mononuclear and multinucleated cells was changed (77.6:23.2 vs 60.8:39.3). The total area of pits per ivory slice was also decreased by adding the OPN antisense oligomer (246813 vs 303139 microns2). These results showed that OPN can be an important mechanism for regulating differentiation and bone resorption.

3T3 Cells↗
PubMed1997

Implantation on the suture material and efficacy of povidone-iodine solution.

Suture implantation of viable exfoliated tumour cells may be responsible for local recurrence of colorectal cancer. Using a colon cancer cell line, we obtained a suture implantation without intraperitoneal metastasis in about 80% of the control animals, when sacrificed on the 2nd postoperative week. The cytotoxic efficacy of povidone-iodine (PVP-I) was tested in vivo by a rat model with viable intracaecal tumour cells, and in vitro by trypan blue exclusion and the MTT assay. In vivo PVP-I at 5% significantly reduced the incidence of tumour growth, while the product at 2.5% had a significant effect in only the monofilament polypropylene group. In an in vitro toxicity study, PVP-I higher than 0.16% was effective at killing almost all tumour cells. PVP-I had effective cytotoxicity in vivo and in vitro, being less cytotoxic in vivo than in vitro.

Animals↗
PubMed1997

[Clinical study in vertiginuous patients suspected of having neurovascular compression syndrome of the eighth cranial nerve].

Neurovascular compression syndrome of the 5th and 7th cranial nerves has been recognized as the cause of trigeminal neuralgia and hemifacial spasm. On the other hand, it is still difficult to diagnose vertigo as neurovascular compression syndrome of the 8th cranial nerve. To detect some specific finding in this syndrome of the 8th cranial nerve, 5 patients with vertigo with hemifacial spasm were examined for the clinical course and neuro-otological features. In all patients MRI and/or angiography suggested vascular compression against the 8th cranial nerve. The clinical courses of these patients revealed various symptoms resembling benign paroxysmal positional vertigo, vestibular neuronitis and Meniere's disease. Audiograms showed two normal hearing patterns, bilateral high frequency hearing loss probably due to aging in one case, bilateral C5-dip in one and fluctuating unilateral hearing loss like Meniere's disease in one. The prolongation of IPL I-III on auditory brainstem response proposed as a criterion by Møller was detected in one case. No response in the caloric test was found in two cases. These abnormalities in the auditory brainstem response and caloric test appeared to be useful for diagnosis but were uncommon findings in all cases. Electronystagmographic examinations including the eye tracking test, optokinetic nystagmus and optokinetic pattern were all normal. We could not find any specific clinical findings valuable for diagnosis of neurovascular compression syndrome of the 8th cranial nerve. It is proposed that the indication of microvascular decompression should be decided carefully.

Cerebral Angiography↗
PubMed1997

MR height of the pituitary gland as a function of age and sex: especially physiological hypertrophy in adolescence and in climacterium.

PURPOSE: To clarify the age- and sex-related changes in pituitary height. METHODS: We reviewed sagittal T1-weighted MR images in 1020 subjects to analyze the size of the pituitary gland. RESULTS: The pituitary height in female subjects (mean, 5.35 mm; SD, 1.2) was significantly greater than that in male subjects (mean, 4.93 mm; SD, 1.0). When the data were analyzed for different age ranges, sex-related differences were statistically significant only in the 10- to 19-, 20- to 29-, and 50- to 59-year-old age groups. The pituitary height peaked in the 20-to-29 age group and tended to decline with age. In female subjects, however, there was a tendency for pituitary height to increase again in the 50-to-59 age group. CONCLUSION: The pituitary height may reflect physiological neuroendocrine differences between younger and older subjects and between male and female subjects. The second increase observed in female subjects may likewise reflect high concentrations of gonadotropic hormones, apparently due to an age-related decline in circulating gonadal steroids and an increase in gonadotropin-releasing hormone.

Adolescent↗
PubMed1997

CMP-NeuAc:Gal beta 1-->4GlcNAc alpha 2-->6sialyltransferase catalyzes NeuAc transfer to glycolipids.

Using mammalian gene-overexpression system, in vitro catalytic activities of CMP-NeuAc:Gal beta 1-->4GlcNAc alpha 2-->6sialytransferase on glycosphinogolipid acceptors were analyzed. We transfected the mammalian expression vector containing the cDNA that was cloned from Daudi cells into COS-1 cells, and selected monoclonal transfectants in the presence of G418. Although the transfected alpha 2-->6sialytransferase can catalyze NeuAc transfer onto glycoprotein acceptors more than glycolipids based on kinetic analyses, the substantial synthesis of IV6NeuAc-nLcOse4Cer was observed and the activities were 7- to 9-times higher in the transfected cells than in the mock transfectants. In addition, the transfected COS-1 cells with alpha 2-->6sialytransferase cDNA were revealed to contain a higher amount of ganglioside that has the terminal NeuAc alpha 2-->6Gal sequence in the in situ situation than the mock transfectants. These results using transfectants, together with those using the purified enzyme protein, suggest that the alpha 2-->6sialytransferase enzyme from Daudi cells can also catalyze NeuAc transfer in alpha 2-->6 linkage onto glycosphingolipid acceptors.

Amino Acid Sequence↗
PubMed1996

Interleukin-3-associated ganglioside GD1a is induced independently of normal interleukin-3 receptor in murine myelogenous leukaemia NFS60 cells transfected with the interleukin-3 gene.

The mechanism of interleukin-3 (IL-3) independent cell growth and of IL-3-associated ganglioside expression was analysed using the IL-3 dependent murine myelogenous leukaemia cell line NFS60-I7 and IL-3 gene-transfected sublines. The transfected cell lines showed autonomous cell growth, tumorigenicity, and IL-3 associated ganglioside GD1a expression in spite of their IL-3 production. While the parental NFS60-I7 cells did not express significant amounts of GD1a, exogenous recombinant IL-3 (rIL-3) was demonstrated to induce IL-3-associated ganglioside GD1a expression in NFS60-I7 cells. Furthermore, the growth potential of the transfected cells was not blocked by anti-IL-3 antibody and expression of GD1a was not affected by anti-IL-3 antibody. These findings suggest that IL-3 expressed intracellularly by gene transfection might act independently of the normal IL-3 receptor on autonomous cell growth and on IL-3-associated GD1a expression in murine myelogenous leukaemia NFS60 cells.

Animals↗
PubMed1996

Three-dimensional imaging of ENT diseases with helical computed tomography.

We have employed helical computed tomography (CT) to evaluate ear, nose and throat diseases, and present herein seven typical cases: middle ear surgery, osteoma of the external ear canal, maxillary fracture, tripod fracture, submandibular gland calculus, epiglottic abscess and vocal fold palsy. Helical (CT) facilitates the assessment of these diseases and its high diagnostic value is described.

Adult↗
PubMed1996

Three-dimensional computed imaging using a personal computer for nasal surgery.

Three-dimensional (3-D) computed imaging was applied before surgery in 16 patients with nasal or paranasal disease. The images obtained by computed tomography (CT) were scanned by a personal computer. The contours of the organs were outlined on the scanned images, and the images were then reconstructed using 3-D imaging software. The resulting 3-D images were evaluated and compared with actual surgical images. The 3-D images were found to be useful for surgical procedures, because they facilitated recognition of the topologic relation between structure and lesion. Although this method requires a personal computer and an image scanner, it is cheaper than, and in some respects even superior to, a 3-D CT system.

Adult↗
PubMed1996

[Functional imaging of the sensorimotor cortex using an ultra-fast MR imaging method].

UNLABELLED: The aim of this study was to assess changes in brain activity during a motor task and variable sensory stimulation using echo planar imaging, which represents the fastest clinically usefull imaging technique available. MATERIALS AND METHODS: The subjects of this study were 11 healthy-volunteers, 4 males and 11 females, with an average of 26.4 years. The subjects were instructed to tap the fingers of one hand as the motor task. Compressed air was applied 5 times a second as "simple" sensory stimulation. Simple figures were drawn on the subjects palm as "complex" sensory stimulation. In all cases, functional imaging was performed by T2*-weighted echo planar imaging (TE = 53 msec, TR = 3000 msec, flip angle = 90 degrees, matrix 64 x 64, FOV = 205 mm, slice thickness = 8 mm) alternately at rest and during the task (intervals: 30 sec). A total of 60 images was collected in 3 minutes. Images obtained by subtracting images at rest and during the task were analyzed. RESULTS AND DISCUSSION: Almost all subjects showed a transient signal increase in the contralateral paracentral region during simple sensory stimulation. Continuous signal increases in the contra- and/or ipsi-lateral para-central region were observed during complex sensory stimulation. Some exhibited signal increases in the parietal or frontal association cortex, but they disappeared when subject's attention was distracted during stimulation. All subjects displayed signal increases in the contralateral para-central region during the motor task. Some of them exhibited signal increases in the medial frontal area (supplementary motor area) and ipsilateral para-central region. These results suggest that the signal increases of functional MRI reflect not only simple reactions to stimulation but higher cerebral function as well.

Adult↗
PubMed1996

[Dual biochemical modulation therapy using 5-FU, leucovorin and cisplatin on human rectal carcinoma xenografts in nude mouse].

This study examined a combined treatment for colorectal carcinoma, the dual biochemical modulation therapy, consisting of 5-FU, Leucovorin (LV) and Cisplatin (CDDP). We compared its anti-tumor effects with other treatments: 5-FU alone, CDDP alone and 5-FU with LV. Primary diffuse infiltrated colorectal carcinoma is well known for its biological malignancy and its lack of response to chemotherapy. We used SRM cells from a cell line of carcinoma of the rectum, and subcutaneously injected them into nude mice. The anti-tumor effects were estimated from the growth rate, inhibition rate and thymidylate synthetase inhibition rates in the tumor tissue. Results indicated that even if the concentration of 5-FU and LV were reduced by half, these combined with CDDP were more effective than other therapies. Dual biochemical modulation therapy is particularly promising because the reduction of the dosages would reduce the side effects while still serving as an excellent anti-tumor therapy.

Animals↗
PubMed1995

Biosynthesis of the so-called "a" and "asialo" pathway glycosphingolipids is differentially regulated in murine myelogenous leukemia NFS60 cells.

Regulation of "a" and "asialo" series ganglioside biosynthesis was analyzed. COS-1 cells expressing only GD1a showed high synthetic activities of GM3, GM2, GM1a, and GD1a, but little activity for GA2 synthesis. However, IL-3-dependent murine NFS60-I7, which has GM1b and GD1 alpha, exhibited high synthetic activities of GM2, GM1a, and GD1a, but GM3 synthase was only 1/6 of COS-1 and GA2 synthetic activity was low. By contrast, IL-3 gene-transfected subline NFS60-H7 expressing GD1a in addition to GM1b and GD1 alpha displayed up-regulated GM3 synthase and GA2 synthase activities, while GM2, GM1a, and GD1a synthase activities were in the same levels as in NFS60-I7 cells. Since GA2 synthetic activities were not parallel with GM2 synthase in the investigated machinery of ganglioside biosynthesis, it is strongly suggested that biosynthesis of "a" and "asialo" series gangliosides is regulated differentially from each other in murine NFS60 cell lines.

Animals↗
PubMed1995

Characterization of blood-group-ABO(H)-active glycosphingolipids in type-AB human erythrocytes.

Neutral glycolipids in Folch's upper phase were isolated from human erythrocyte membranes of 22 individuals with blood type AB. On immunostaining by TLC with anti-A IgG, all reactive glycolipids in type A corresponded to reactive glycolipids in type-AB erythrocytes. With anti-B IgM, all reactive glycolipids in type-B erythrocytes also corresponded to reactive glycolipids in type-AB erythrocytes. By comparison of the reactivity to that of the anti-A and anti-B antibodies, it was found that, in type-AB erythrocytes, all glycolipids reactive with either one of the anti-A or anti-B antibodies were detected in both type-A and type-B erythrocytes, and that A-active glycolipids had higher Rf values than B-active glycolipids on TLC plates. A series of glycolipids reactive with both antibodies were purified from the Folch's upper neutral glycolipid fraction of erythrocyte membranes by column chromatography, and was characterized by TLC-immunostaining and negative secondary-ion mass spectrometry. The results strongly suggested that A-active and B-active carbohydrate chain epitopes existed separately as glycolipid molecules in blood-type-AB erythrocytes. It was also confirmed that these phenotypes observed in erythrocyte membranes were exhibited by blood-group-active glycosphingolipids in the small intestine of blood-type-AB individuals. Furthermore, upon treatment of fractions obtained from silicic acid column chromatography with alpha-N-acetylhexosaminidase or alpha-galactosidase, a branched hybrid-type molecule with both A and B determinants was not detected.

ABO Blood-Group System↗
PubMed1995

Interleukin-3-associated expression of gangliosides in mouse myelogenous leukemia NFS60 cells introduced with interleukin-3 gene: expression of ganglioside GD1a and key involvement of CMP-NeuAc:lactosylceramide alpha 2-->3-sialyltransferase in GD1a expression.

Murine interleukin-3 (IL-3)-associated expression of gangliosides has been investigated using a gene transfection technique. A murine IL-3 cDNA was introduced into the parental NFS60-17 cells that was exclusively dependent on IL-3. We analyzed the glycosphingolipids from the parental cells and the transfected cells by fast atom bombardment mass spectrometry analyses and/or immunostaining techniques using specific antibodies. Two major gangliosides, IV3NeuAc-GgOse4Cer (GM1b) and IV3-NeuAc,III6NeuAc-GgOse4Cer (GD1 alpha), were expressed, in the parental cells. By contrast, in the IL-3 gene-transfected cells, a ganglioside IV3NeuAc,II3NeuAc-GgOse4Cer (GD1a) was strikingly expressed, in addition to GM1b and GD1 alpha that were already present in the parental cells. In spite of various IL-3-secreting capabilities, all transfectants investigated have exhibited the same ganglioside patterns and expressed GD1a. Furthermore, the appearance of GD1a was a consequence of the up-regulation of a single glycosyltransferase, CMP-NeuAc:lactosylceramide alpha 2-->3-sialytransferase (GM3 synthase). Activities of the other downstream glycosyltransferases that were involved in GD1a synthesis were not significantly different between the parental and the transfected cells. According to these data, the progression of tumor stage by the acquisition of autonomous cell growth ability after IL-3 gene transfection resulted in dramatic changes in cell surface gangliosides and their biosynthetic pathways. GD1a could be considered as an IL-3-associated ganglioside and was expressed in a tight connection with a single glycosyltransferase (GM3 synthase) up-regulation and with IL-3 expression in murine myelogenous leukemia cells.

Animals↗
PubMed1995

A study by means of a new assay of the relationship between an outbreak of erythema infectiosum and non-immune hydrops fetalis caused by human parvovirus B19.

An enzyme-linked immunosorbent assay (ELISA), used to detect IgG and IgM antibody specific for human parvovirus B19, was established by use of human parvovirus B19 capsid protein VP-1 expressed in Escherichia coli. Paired samples of serum derived from 44 mothers and single samples derived from 24 babies having unexplained non-immune hydrops fetalis (NIHF), were tested by means of the assay. Five cases (11%) of NIHF were suspected of having been induced by intrauterine human parvovirus B19 infection because the samples of maternal serum were positive for parvovirus B19 IgM antibody. Four of the five cases arose during an outbreak of erythema infectiosum. According to our study and previous reports over 90% of NIHF caused by parvovirus B19 intrauterine infection have become clinically overt in the second trimester of pregnancy during a period ranging from 15 to 27 weeks of gestation.

Blotting, Western↗
PubMed1995

A case with symptoms of vestibular neuronitis caused by an intramedullary lesion.

We report on a patient with an intramedullary lesion who showed only symptoms of so-called vestibular neuronitis. From the neurological aspects and MRI findings, the lesion was thought to be localized to the vestibular nerve in the pons. Cerebrospinal fluid testing and MRI findings suggested a diagnosis of multiple sclerosis (MS), although the clinical features were not compatible with MS. This case may shed some light on the aetiology of vestibular neuronitis.

Adolescent↗
PubMed1995

Hypertrophic anterior falx artery associated with interhemispheric subdural empyema--Case report.

A 14-year-old boy presented with interhemispheric subdural empyema. Angiography demonstrated a hypertrophic anterior falx artery. He was treated with antibiotics and craniotomy to evacuate the lesion. The postoperative course was uneventful with no signs of neurological deficit. The abnormal artery was no longer visualized angiographically after the resolution of the empyema. Reactive appearance of the anterior falx artery is a pathognomonic sign of interhemispheric subdural empyema.

Adolescent↗