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T Ohsawa

Publications and source records attributed to T Ohsawa.

At least 55 records · Page 3Linked to original sources
PubMed1994

Results of combined resection of invaded organs in patients with potentially curable, advanced gastric cancer.

OBJECTIVE: To assess the role of combined resection of neighbouring organs that have been invaded by cancer in patients with potentially curable, but advanced, gastric cancer. DESIGN: Retrospective follow up study. SETTING: University department of surgery. SUBJECTS: 204 patients (from a consecutive series of 745 who had had gastric resection for cancer) all of whom had undergone potentially curative operations for advanced disease: 91 had had combined resection of other invaded organs. RESULTS: Five year survival was 65% for 113 patients who had gastrectomy alone and 46% for 91 patients who also had other affected organs resected (p < 0.02). CONCLUSION: We recommend resection of all organs that have been invaded by cancer, provided that there is no evidence such as widespread nodal involvement, peritoneal dissemination, or extensive hepatic metastases, that would make cure impossible.

Diaphragm↗
PubMed1993

Anti-B-series ganglioside-recognizing autoantibodies in an acute sensory neuropathy patient cause cell death of rat dorsal root ganglion neurons.

To examine the cytotoxicity of a patient's serum with an acute relapsing sensory neuropathy syndrome, dorsal root ganglion neurons from young adult rats were cultured in the presence of the patient's serum which had an extremely higher-titer monoclonal IgM antibody recognizing B-series gangliosides, GD2, GD1b, GT1b and GQ1b. By the addition of the inactivated patient's serum, the relatively larger cells died after undergoing of metamorphosis during several hours of culture, whilst the smaller cells survived. The IgM fraction isolated from the patient's serum showed similar cytotoxicity towards the neurons as the inactivated whole serum. No cytotoxicity was observed with the IgM fraction-containing medium after it had been absorbed with ganglioside GD1b. The results suggested that the anti-B-series ganglioside-directed antibody is the causal agent for the human neurologic disease.

Acute Disease↗
PubMed1993

[Ankylosing spondylitis with acute anterior uveitis--correlation between HLA-B27 and clinical and radiologic findings].

Six cases of ankylosing spondylitis (AS) complicated with acute anterior uveitis (AAU) were reviewed. Clinical and radiologic findings of these cases were correlated with HLA-B27. All the patients were men; four of them were HLA-B27 positive, and two were B27 negative. The average age of onset was younger in B27+ patients than in B27- patients. Ophthalmologic study showed no definite difference in inflammatory change of AAU between B27+ patients and B27- patients. AAU in B27+ patients was completely cured in three months. A history of low back pain was more apparent in B27+ than in B27- patients. Three out of four B27+ patients showed complete bony ankylosis in sacroiliac joints, whereas no ankylosis was seen in B27- patients. CT scan was useful to demonstrate sacroilitis in cases with equivocal radiologic findings. Spondylitic changes were more extensive in B27+ than in B27- patients. The results support the concept that HLA-B27+ AS and B27- AS are different entities with similar phenotypic expression, and HLA-B27 is an arthritogenic gene in the Japanese population as well.

Acute Disease↗
PubMed1993

Similar responses to pharmacological agents of 1,2-OAG-induced compaction-like adhesion of two-cell mouse embryo to physiological compaction.

A comparison was made of responses to pharmacological agents between cell adhesion induced by an activator of Ca(2+)-phospholipid-dependent protein kinase (PKC) and physiological compaction in mouse embryos. An activator of PKC, 1-oleoyl-2-acetyl-sn-glycerol (1,2-OAG) induced the compaction-like adhesion of cells in two-cell embryos within 5-10 min and the adhesion lasted during the course of treatment for 1 h. W-7 and W-5 (calmodulin antagonists) and cytochalasin B and cytochalasin D (inhibitors of the polymerization of microfilaments) each completely interfered with the 1,2-OAG-induced adhesion of cells. Two-cell embryos having once shown evidence of cell adhesion in response to 1,2-OAG were decompacted when they were transferred to a medium that contained 1,2-OAG and any one of the agents described above. Colchicine and colcemid (inhibitors of the polymerization of microtubules) and tunicamycin (an inhibitor of N-linked protein glycosylation) each had no effect on the 1,2-OAG-induced adhesion of cells. In Ca(2+)-free medium, treatment with 1,2-OAG failed to induce any cell adhesion. These results are very similar to those reported for physiological compaction at the late eight-cell stage. Thus, the compaction-like adhesion of cells in mouse embryos at the two-cell stage appears to be a calmodulin-dependent process, requiring assembled microfilaments and extracellular Ca2+ ions but not microtubules or N-linked glycoproteins as is the case for the physiological compaction.

Animals↗
PubMed1993

Involvement of protein kinase C in nuclear migration during compaction and the mechanism of the migration: analyses in two-cell mouse embryos.

Compaction and nuclear migration occur in mouse embryos at the late eight-cell stage. It has been reported that activators of protein kinase C (PKC) increase adhesion of cells at the two-cell, four-cell, and uncompacted eight-cell stage. We report here that nuclear migration followed the increased adhesion of cells in such embryos when they were treated with PKC activators. These cellular events resembled those in normal embryos at the late eight-cell stage and were blocked by sphingosine, a PKC inhibitor. The responses were proportional to the dose of the PKC activator. Molecular analogues of the PKC activators, which do not affect PKC, did not induce these events. These results suggest an important role for PKC in initiation of nuclear migration as well as in compaction. Experiments were also conducted to identify the source of the mechanical force that moves the nucleus. Nuclear migration was suppressed in embryos pretreated with colchicine. Calmodulin is known to have effects on Ca(2+)-induced assembly and disassembly of microtubules. The calmodulin antagonists W-7 and W-5 suppressed nuclear migration. These results suggest that microtubules are essential for the migration and that nuclei are migrated via the Ca(2+)-induced, calmodulin-mediated assembly and disassembly of the microtubule networks. Together, these results obtained with PKC activators/inhibitor, colchicine, and calmodulin antagonists suggest that nuclear migration is mediated by increases in PKC activity, requires intact microtubules, and is accompanied by PKC-dependent increases in cell-cell adhesion.

Animals↗
PubMed1993

Susceptibility effects of bone trabeculae. Quantification in vivo using an asymmetric spin-echo technique.

RATIONALE AND OBJECTIVES: The authors assessed the capability of magnetic resonance imaging in measuring bone mineral density in vivo. METHODS: Using the in-phase asymmetric spin-echo technique, the susceptibility effect (T2*susceptibility) was measured in lumbar vertebrae in vivo. Calcium density was measured with single energy quantitative computed tomography scan. The values of the susceptibility effect were correlated with calcium density. RESULTS: A statistically significant positive correlation was observed between signal loss due to susceptibility-induced inhomogeneity and the calcium density in the region of interest. The change in 1/T2*susceptibility per unit change in density was 0.114 seconds-1/mg/cm3. T2*susceptibility was 14.3 mseconds in volunteers and 17.4 mseconds in postoophorectomy patients. CONCLUSIONS: To some extent, quantification of bone density is possible using magnetic resonance imaging; however, the relatively wide dispersion of the susceptibility effect, plotted against the calcium density in the axial skeleton, indicates that other factors, such as the three-dimensional structure of bone trabeculae, may play important roles in determining magnetic resonance parameters.

Adult↗
PubMed1993

Frequent presence of anti-GQ1b antibody in Fisher's syndrome.

We used the enzyme-linked immunosorbent assay to investigate autoantibodies against the gangliosides GM1, GD1a, GD1b, GT1b, GD2, and GQ1b in sera from 16 patients with Fisher's syndrome. We found high anti-GQ1b antibody titers, mainly those of the IgG class, in the sera of 13 of these patients. The titers decreased with the clinical course of the illness. Moreover, anti-GQ1b antibody-positive patients had more severe ataxia of cerebellar type than the antibody-negative patients.

Adult↗
PubMed1993

CT visualization of the major pulmonary fissures: value of 25 degrees cranially tilted axial scans.

OBJECTIVE: CT visualization of the major (oblique) pulmonary fissures is often hampered by partial volume effects of adjacent lung parenchyma. We attempted to improve visualization of the fissures by using 25 degrees cranially tilted axial scans. An initial in vitro study also was performed. MATERIALS AND METHODS: Both conventional and 25 degrees tilted axial CT scans were obtained in 40 adult patients. After scans with 2-mm collimation were obtained at 1 cm and 6 cm below the carina, the gantry was tilted 25 degrees cranially to be perpendicular to the plane of the major fissures, and scans with 2-, 5-, and 10-mm collimation were obtained at the same two levels. The appearance of the fissures was classified as linear opacity, band-like opacity, or avascular area for each lung at each level. RESULTS: On 2-mm conventional axial scans, the major fissures were seen as linear opacities in three to 23 patients (8-58%), as band-like opacities in 13-31 (32-78%), and as avascular areas in one to seven (2-18%). (Ranges indicate lowest and highest values when data for the two levels in the two lungs are grouped separately.) On 2-mm tilted scans, the ranges were 32-38 patients (80-95%), one to eight (2-20%), and zero to one (0-2%), respectively. The 2-mm tilted scans were significantly superior to the 2-mm conventional axial scans for showing the fissures (p < .01). Direct visualization as linear or band-like opacities was possible even on 10-mm tilted scans in 15-32 cases (38-80%). CONCLUSION: Our results show that visualization of the major fissure is improved when tilted CT scans rather than conventional axial scans are used.

Adult↗
PubMed1993

[Hyperlipidemia].

Explore the source record for details and available documents.

Adolescent↗
PubMed1992

Obliteration of the descending aortic interface in pectus excavatum: correlation with clockwise rotation of the heart.

Obliteration of the descending aortic interface is a new radiographic finding in pectus excavatum. Seventy frontal and lateral chest radiographs and 33 computed tomographic (CT) scans of patients with pectus excavatum were retrospectively reviewed to evaluate the frequency, possible cause, and clinical significance of this finding, which was detected in 21 of 70 cases (30%) of pectus excavatum. No significant relationship was found between this finding and the extent of the thoracic deformity. In patients with this finding, the left inferior pulmonary vein (PV) entered the left atrium at an acute angle to the sagittal plane, as demonstrated at CT, and this angle was significantly smaller than that in patients without this finding. The PV angle also significantly correlated with the cardiac rotation angle. In pectus excavatum, partial obliteration of the descending aortic interface can be mistaken for adjacent disease.

Adult↗
PubMed1992

Laser diffraction estimation of particle size distribution of slightly water-soluble drugs coexisting with additives: application to solid dosage forms.

A simple and quantitative evaluation method for particle size distribution (fx(r)) of slightly water-soluble drugs dispersed in an aqueous medium together with other water-insoluble additives was developed using a laser diffraction method. The particle size distribution function of the powder mixture, (f(r)), was assumed as f(r) = phi x.fx(r) + phi a.fa(r), where phi is the volume fraction of each component dispersed in a measurement medium and fa(r) is the distribution function of another water-insoluble additive "a". In order to calculate fx(r) from f(r), it is necessary to know the density of drug and additive in the measurement medium, d(x) and d(a), but this is difficult to determine since particles usually swell in the medium. Thus, a method was developed to use their relative value, delta a (= da/dx). As a practical application, oxolinic acids (OA) of three sizes (OA-S (about 2 microns), OA-M (about 7 microns) and OA-L (about 24 microns)) were used as model drugs. delta a values were determined for various additives using the mixture of OA-S and each additive. Then, using delta as, fx(r) of OA-M or OA-L in the mixture containing OA-M or OA-L and additives was calculated from the f(r) experimentally determined for the mixture. They agreed well with their original distributions. The method was applied to some dosage forms, and the results obtained had good correlation with those from turbidity, wet sieving or dissolution test.

Algorithms↗
PubMed1991

Age-related alteration of brain gangliosides in senescence-accelerated mouse (SAM)-P/8.

The senescence-accelerated mouse (SAM)-P/8 was examined with respect to changes in the content and composition of brain gangliosides during aging from juvenile to senescence. The gangliosides were compared with those of control mice, senescence-accelerated resistant mouse (SAM)-R/1. The ganglioside contents in the whole brains of SAM-P/8 and -R/1 were at almost constant level from 0.5 to 6 months, but decreased thereafter until senescence to about 80% of the levels reached at the younger ages. Upon aging, the ganglioside compositions changed with an increase of GM1, and decreases of GD1a, GD1b and GT1b in both strains (GT1b greater than GD1a greater than GD1b). A minor component, GM3 was two to four fold higher in the molecular distributions of the whole brain gangliosides of SAM-P/8 than those of -R/1 at any age examined throughout the life span. The regional gangliosides in olfactory bulb, cerebral cortex, hippocampus, hypothalamus, cerebellum, corpora quadrigemina region, brain stem and medulla oblongata were compared between the two strains at the age of three months. The ganglioside contents in the brain stem and medulla oblongata were lower in SAM-P/8 than -R/1, but there was no significant difference between the two strains in the other regions. As a minor component, GM3 was found to occur in a higher concentration in SAM-P/8 than -R/1 in all brain regions examined, except in the olfactory bulb where GM3 was detected as a major component with no difference in the distribution level between the two strains.

Aging↗
PubMed1990

[MR imaging of the carpal tunnel syndrome].

Magnetic resonance (MR) imaging of the carpal tunnel was performed in 23 wrists of 13 patients who were suspected to have carpal tunnel syndrome (CTS). In ten out of 23 wrists, diagnostic images of the carpal tunnel could be obtained. MR images were analysed retrospectively as to swelling of the median nerve, signal intensity of the median nerve on T2 weighted image, and swelling of the tendon sheath. In 8 wrists the median nerve was significantly swollen at the inlet of the carpal tunnel. Four of them showed increased signal intensity of the median nerve on T2 weighed image at the inlet. Swelling of the tendon sheath was demonstrated in two cases. These finding seem to represent edematous change of the median nerve due to compression. Surgical correlation was obtained in two wrists. Since MR imaging is capable of demonstrating pathological changes of the median nerve in CTS, it can be a diagnostic tool in selected cases.

Adult↗
PubMed1990

Rat dorsal root ganglion gangliosides during early development until senescence.

The gangliosides of male rat dorsal root ganglia were studied during aging from the first day postnatally until senescence at 24 months. The ganglioside contents increased drastically until 12 months after birth and thereafter did not change considerably, and the increase pattern was in parallel with the increase of wet weight of the tissues. The major gangliosides of the dorsal root ganglia were GM3, LM1 (sialosyl-lactoneotetraosylceramide), unknown ganglioside X, GD1a, GD1b, GT1b and GQ1b. The most drastic changes in ganglioside composition were observed between the ages of postnatal day 1 and 1.5 months. The unknown ganglioside X (dominant at postnatal day I) decreased up to 1.5 months. In contrast, LM1, a minor ganglioside postnatal day 1, increased until 1.5 months of age. Except for these changes, the other gangliosides were present at almost constant ratios in the component profiles during aging until senescence.

Aging↗
PubMed1990

Prosthetic treatment for speech disorders due to surgically acquired maxillary defects.

To evaluate speech following prosthetic obturation of surgically acquired maxillary defects, the speech intelligibility of eight patients was measured preoperatively and postoperatively, with and without prostheses. Oro-nasal separation and velopharyngeal function were also evaluated by use of a specially designed spirometer and endoscope. Following placement of maxillary obturator prostheses, four patients achieved dramatic improvement in speech intelligibility, while four patients did not. In the latter, insufficient improvement in speech intelligibility was attributed to velopharyngeal incompetence or unstable prosthesis. Two of three patients with velopharyngeal incompetence did achieve adequate improvement in speech following placement of a speech appliance in combination with maxillary obturator prostheses.

Adult↗
PubMed1990

[High-resolution CT in evaluation of temporal bone trauma].

High-resolution CT (HRCT) examinations were performed in 22 patients with temporal bone trauma. The CT findings were correlated with the clinical signs and symptoms, routine head CT findings were also examined. HRCT was able to demonstrate fracture lines, ossicular chain disruptions, facial nerve injuries, and hemotympanums in majority of cases. Associated many severe head injuries (brain contusion etc.) were noted in the routine head CT.

Adolescent↗