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T Kohno

Publications and source records attributed to T Kohno.

At least 253 records · Page 14Linked to original sources
PubMed1995

Application of a new tactile sensor to thoracoscopic surgery: experimental and clinical study.

BACKGROUND: We developed a new tactile sensor that could quantify the hardness of objects as changes in the resonance frequency of the sensor (delta f). We have applied it to thoracoscopic operations for the localization of small invisible nodules in the lung. METHODS: When the sensor probe was moved over the lung surface, a delta f curve was depicted on the computer screen. When the sensor tip reached a point directly above a hard object, a sudden upward jump of the delta f curve was evoked. After experimental studies using pigs, the sensor was applied in 8 patients. More recently we produced a needle sensor to distinguish small nodules from bronchi that may evoke similar upward jumps of the delta f curve. Eight nodules and four bronchi in resected human lungs were probed directly using this sensor. RESULTS: In all of the patients, the hardness of various thoracic structures could be quantified. A total of 10 nodules were found using the sensor and resected thoracoscopically. The needle sensor distinguished nodules from bronchi, as the mean delta f of the bronchial walls (-64 +/- 45.9 Hz) was significantly higher than that of nodules (-526 +/- 168 Hz, p < 0.001). CONCLUSIONS: Thoracoscopic detection of small and invisible pulmonary nodules using our new tactile sensor is feasible.

Adenocarcinoma↗
PubMed1995

Prevention of chronic relapsing experimental autoimmune encephalomyelitis by soluble tumor necrosis factor receptor I.

We have evaluated the effect of the type I (p-55, type beta) soluble tumor necrosis factor receptor (sTNFrI) in an animal model of multiple sclerosis. Experimental autoimmune encephalomyelitis (EAE) was induced in SJL/J mice by adoptive transfer of T lymphocytes sensitized to myelin basic protein (MBP). sTNFrI completely blocked both clinical signs of disease and pathological changes that included CNS demyelination and inflammatory cell infiltration. Effective inhibition of disease expression was obtained using several different regimens of subcutaneous (s.c.) injection. These included daily doses starting at day 0, every other day injections starting at day 0, daily doses starting on day 4, and two doses separated by 12 h on day 1 and 2. Furthermore, treatment with sTNFrI for 15 days completely protected these animals from the recurrent episodes of disease normally associated with adoptively transferred EAE. These findings suggest that TNF plays a major causative role in EAE and that the sTNFrI may prove to be a useful therapeutic approach in multiple sclerosis.

Animals↗
PubMed1995

Sandwich capture enzyme immunoassay for water soluble blood group B substance in secretor saliva.

Sandwich capture enzyme immunoassays (EIA I and EIA II) are described. Water soluble B substance was reacted simultaneously with affinity-purified dinitrophenyl goat anti-B IgG and affinity-purified goat anti-B IgG-peroxidase conjugate. The complex formed of B substance, dinitrophenyl IgG and IgG-peroxidase conjugate was trapped onto a polystyrene ball coated with affinity-purified goat anti-dinitrophenyl bovine serum albumin IgG. After washing, peroxidase activity bound to the ball was assayed by fluorometry (the sandwich capture EIA I). In the sandwich capture EIA II, the complex was, after thorough washing, eluted from the ball with dinitrophenyl-L-lysine, and then peroxidase activity in the eluate was assayed. The thorough washing and elution processes improved the sensitivity 3.3-fold, and B substance in saliva samples from type B and AB secretors could be detected 200- to 500-fold more sensitively than hemagglutination inhibition, a method commonly used in forensic practices.

ABO Blood-Group System↗
PubMed1995

Identification of a novel phospholipase C family gene at chromosome 2q33 that is homozygously deleted in human small cell lung carcinoma.

Since a considerably high incidence of allelic loss on chromosome 2q was detected in lung carcinoma and a homozygous deletion at chromosome 2q33 was detected in a small cell lung carcinoma cell line, NCI-H82, a novel tumor suppressor gene has been suggested to be present in this chromosomal region. In the present study, we constructed a cosmid contig map covering the homozygous deleted region, which was estimated as being 220 kbp in size, and identified a gene from the deleted region. All of the coding exons of this gene were homozygously deleted in this cell line, while a 5'-non-coding exons was retained. Since the gene encodes a protein with striking similarity to several members of a family of phospholipase C, we designated this gene as PLC-L (phospholipase C-deleted in lung carcinoma). The PLC-L gene was expressed in a variety of fetal and adult organs including the lung. However, its expression was greatly reduced in seven of 13 (53.8%) of small cell lung carcinoma and 13 of 15 (86.7%) of non-small cell lung carcinoma cell lines. Since its homology to phospholipase C genes suggests the involvement of the PLC-L gene in inositol phospholipid-based intracellular signaling cascade, it is possible that aberrant expression of the PLC-L gene contributes to the genesis or progression of human lung carcinoma.

Amino Acid Sequence↗
PubMed1995

Combined inhibition of interleukin-1 and tumor necrosis factor in rodent endotoxemia: improved survival and organ function.

The interleukin (IL)-1 receptor antagonist (Ra) and a polyethylene glycol-linked dimer of the type I soluble receptor of tumor necrosis factor (TNF), PEG-(rsTNF-RI)2, were used to determine whether maximal protection against lethality and organ dysfunction is achieved by single or dual cytokine inhibition under rigorous conditions of rodent endotoxemia. Inhibition of IL-1 or TNF alone protected maximally against lethality when inhibitors were given simultaneously with lipopolysaccharide (LPS) under minimal lethal conditions. Combined inhibition of IL-1 and TNF was necessary to maximally protect against lethality when treatment was delayed until 7 h after LPS injection under minimal lethal conditions or when treatment was begun immediately after LPS injection under supralethal conditions. Improved survival in IL-1Ra- plus PEG-(rsTNF-RI)2-treated rats was associated with enhanced protection against renal and metabolic dysfunctions. Thus, under very severe conditions of endotoxemia, TNF and IL-1 may act independently to mediate lethality and some organ dysfunctions.

Animals↗
PubMed1995

Human T-lymphotropic virus type I-associated uveitis in patients with Graves' disease treated with methylmercaptoimidazole.

Human T-lymphotropic virus type I (HTLV-I) is responsible for a certain form of uveitis [HTLV-I-associated uveitis (HAU)]. A previous history of Graves' disease has been reported in 9-17% of the patients with HAU. In this study, the prevalence of patients with either HTLV-I antibody or uveitis was evaluated in 819 consecutive patients with thyroid disorders between 1991 and 1992. Serum HTLV-I antibody was found in 25 of 392 patients with Graves' disease, 19 of 257 with chronic thyroiditis, and 3 of 170 with nodular goiter. Five of 25 HTLV-I-positive patients with Graves' disease developed HAU. All of these 5 patients had been treated with methylmercaptoimidazole (MMI). Within a few months before the onset of uveitis, 3 patients were hyperthyroid, and 2 were hypothyroid. In 2 of 5 patients, an exacerbation of uveitis occurred soon after the readministration of MMI for the relapse of hyperthyroidism. None of the 367 HTLV-I negative patients with Graves' disease nor 22 HTLV-I-positive patients with chronic thyroiditis or nodular goiter developed uveitis. It was therefore suggested that Graves' disease, thyroid dysfunction and/or MMI administration might be related to the development of HAU.

Adult↗
PubMed1995

Enterogenous cyst in the fourth ventricle--case report.

A 53-year-old male presented with a rare enterogenous cyst in the fourth ventricle associated with repeated ventriculoperitoneal shunt malfunction. Surgical excision of the cyst resolved the shunt problems. Electron microscopy findings of the surgical sample were microvilli covered with electron-dense coating materials, basement membrane, and several intercellular junctional devices, suggesting the cyst was derived from the endodermal structure. The viscous and gelatinous contents of the cyst might be responsible for the shunt malfunction.

Cerebral Ventricles↗
PubMed1995

Three-dimensional structure of the perimysium in sternocleidomastoid muscle.

The morphology of the sternocleidomastoid muscle (SCM) of human fetuses, ranged from 12 to 32 weeks gestation, was investigated by a light microscopy and a scanning electron microscopy. The collagenous fibers of the perimysium of the SCM formed complex structures from 24 weeks gestation by contrast to fibers of the endomysium of the SCM. The cross-sectional area (CSA) of the bundle of muscle fibers and the CSA of the individual muscle fibers of the SCM increased during development from 12 to 32 weeks gestation, in a process linked to the development of the perimysium. Therefore the perimysium affects and controls to the muscle fiber of the developed SCM and acts to resisting stretch forces in the movements. The changes in the arrangement and development of the collagenous fibers in the perimysium may be correlated to with these of the muscle fibers.

Clavicle↗
PubMed1995

Effects of delayed visual information on the rate and amount of prism adaptation in the human.

Accurate reaching towards a visual target is initially disturbed when the visual field is displaced by prisms, but recovers with successive trials. To determine how the improvement depends on the visual error signals associated with the motor output, the time course of prism adaptation was studied with delayed visual information on the error. Subjects were trained to reach rapidly at a target on a tangent screen. Vision was always blocked during the movement, and allowed again only after the index finger touched the screen. One experiment consisted of three sets of 30 trials. In the first set, the subject wore no prisms and vision was allowed without delay. In the second, the visual field was displaced by prisms, and vision was available only after a delay period of 0-10,000 msec while the subjects maintained their final pointing position. Initially, the subject misreached the target by about the amount of visual displacement (60 mm). Errors decreased with trials by an amount proportional to the error in the preceding trial. The rate of decrease of error was generally largest when the delay was 0 msec, became significantly smaller when the delay was 50 msec, and showed only gradual change with longer delays. In the third set, the subject wore no prisms and vision was allowed without delay. Initial misreaching in the direction opposite to the visual displacement, reflecting the amount of adaptation in the second set, was generally largest with no delay (median of 46 mm) and significantly smaller with 50 msec and longer delays (17-33 mm).(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗
PubMed1995

[Bronchogenic carcinoma associated with right aortic arch and postaortic left brachiocephalic vein--report of a case].

61-year-old male was admitted to our hospital for surgical treatment of bronchogenic squamous cell carcinoma arising from left B8. The patient had right aortic arch with aberrant left subclavian artery and postaortic left brachiocephalic vein. Intraoperatively, left ligamentum arteriorsus forming vascular ring between the left subclavian artery and the pulmonary artery was found, however the ligamentum arteriorsus was not divided because no symptom of esophago-tracheal compression was observed. The left brachiocephalic vein was located between the ascending aorta and the arterial ligament. The lower lobe of the left lung was resected, and lymph nodes in the left side of the mediastinum were dissected easily because the aortic arch was positioned on the other side. Preoperative assessment of the type of branching and the course of arteries and veins is important for safe operation.

Aorta, Thoracic↗
PubMed1995

[New tactile sensor for thoracoscopic detection of intrapulmonary nodules].

We have developed a new tactile sensor which can be used for thoracoscopic detection of invisible intrapulmonary nodules. We applied this new device for consecutive ten cases to excise twelve intrapulmonary nodules thoracoscopically from August 1994 to January 1995. In this report, one of ten cases was presented. The patient was a forty-three-year-old female and admitted with an indeterminate nodule on chest X-ray and computed tomography. When the sensor probe quantifying the hardness of objects by the changes in resonance frequency of the sensor (delta f) passed above the nodule, a sudden jump was evoked in delta f curve on the computer screen. The nodule was resected thoracoscopically and proved pathologically to be adenocarcinoma. Thoracoscopic procedure was then converted to open thoracotomy and lobectomy with lymph node dissection was performed.

Adenocarcinoma↗
PubMed1995

[Solitary rectal carcinoma metastasis to the left hilar lymph nodes: a case report].

A 66-year-old woman was referred to this institution for treatment of hemoptysis, atelectasis of the left upper lobe, and marked hypoxia necessitating oxygen therapy. A low anterior resection of the rectum had been performed for rectal adenocarcinoma 6 years and 3 months before this admission, and was followed by another resection after a local recurrence 20 months later. Bronchoscopy revealed an endobronchial tumor obstructing the left upper lobe bronchus. Tissue from a transbronchial biopsy revealed metastatic rectal carcinoma of the endobronchial lumen. There was no evidence of local recurrence or metastasis to other organs. A left pneumonectomy and lymph node dissection were performed successfully. The postoperative course was uneventful, and the patient was discharged after marked improvement of the arterial blood gas results. The pathological diagnosis of a resected tissue specimen was metastatic adenocarcinoma of the left hilar lymph nodes with invasion of the left main bronchus and protrusion into the endobronchial lumen. The patient remained disease-free for 6 months. At that time, computed tomography of the chest disclosed small metastases in the right lung and chemotherapy was begun.

Adenocarcinoma↗
PubMed1994

Frequent allelic losses on chromosomes 2q, 18q, and 22q in advanced non-small cell lung carcinoma.

Although it is widely accepted that tumor suppressor genes play an important role in the genesis and progression of human cancer, little is known about genetic events that accumulate during multistage lung carcinogenesis. Thus, to determine a subset of tumor suppressor genes that are involved in the genesis and progression of non-small cell lung carcinoma (NSCLC), 22 brain metastases and 23 stage I primary lung tumors were examined for allelic losses at 40 loci on 10 chromosomes including the loci of 5 tumor suppressor genes, APC, WT1, RB, p53, and DCC. The incidence of allelic losses on chromosomes 3p, 13q, and 17p was high (> 60%) in both primary tumors and brain metastases. In brain metastases, a high incidence of allelic losses (> 60%) was also observed at loci on chromosomes 2q, 18q, and 22q, and the incidence of allelic losses on these chromosomes in brain metastases was significantly higher than that in primary tumors (P < 0.05). In two cases of brain metastases with corresponding primary lung tumors, sequential accumulation of allelic losses during progression of primary lung tumors was observed on several chromosomes including chromosomes 2q and 18q. These results indicate that, besides loss of heterozygosity for chromosomes 3p, 13q, and 17p, loss of heterozygosity for chromosomes 2q, 18q, and 22q also occurs frequently in advanced NSCLCS. Thus, it is possible that loss of heterozygosity on chromosomes 2q, 18q, and 22q occurs late in the progression of NSCLC and/or causes phenotypic alterations of NSCLC cells into more aggressive ones.

Base Sequence↗
PubMed1994

Hydroxyl group of Tyr13 is essential for the activity of omega-conotoxin GVIA, a peptide toxin for N-type calcium channel.

A series of analogs of omega-conotoxin GVIA, a peptide neurotoxin having 27 amino acid residues with three disulfide bridges, were synthesized by replacing each amino acid residue except for Cys and Hyp with Ala. CD spectra were virtually identical between native and all of the analogs, indicating the overall conformations were not changed by the substitutions. The inhibitory effects of these analogs on 125I-omega-conotoxin GVIA binding to chick brain synaptic plasma membranes showed that replacement of Tyr13 with Ala drastically lowered the affinity of the toxin to the N-type Ca2+ channel. Substitution of Tyr13 with Phe also showed reduction of the affinity, indicating that the hydroxyl group of Tyr13 is critical for binding. Since Lys2 is also important for binding (Sato, K. Park, N.-G., Kohno, T. Maeda, T., Kim, J.-I., Kato, R., and Takahashi, M. (1993) Biochem. Biophys. Res. Commun. 194, 1292-1296), we propose a two-point binding model in which Tyr13 and Lys2 interact with specific amino acid residues of the Ca2+ channel through hydrogen bonding and ionic interaction, respectively.

Amino Acid Sequence↗
PubMed1994

TNF and its receptor antibody agonist differ in mediation of cellular responses.

TNF binds to two distinct receptors designated p60 and p80. Because Abs to the p60 receptor (anti-p60) can mimic TNF, we therefore compared the cellular signaling of TNF with that of anti-p60. We demonstrate both qualitative and quantitative differences between TNF and anti-p60. HepG2 cells, which express the p60 receptor, were found to be completely resistant to TNF but highly sensitive to the antiproliferative effects of anti-p60. In contrast, normal fibroblasts were found to be several fold more sensitive to TNF than to anti-p60. Several other epithelial cell lines that also express primarily the p60 receptor showed quantitative differences in mediation of cellular responses by TNF and anti-p60. The blocking of the p60 receptor by TNF had no effect on the response of HepG2 cells to anti-p60, suggesting a difference in their binding sites. Anti-p60, however, inhibited the effect of TNF on fibroblasts. Ab against the p80 receptor had no effect by itself or on the effect of TNF and anti-p60. The difference in the response to TNF and anti-p60 could not be correlated to the differences in the level of expression of p60 receptor on these cells. Furthermore, cycloheximide potentiated the TNF-mediated effect but not that mediated through anti-p60, thus also indicating a difference in the mechanism of action of these two agents. Overall, these results demonstrate that TNF and anti-p60, although both working through the p60 receptor, differ in their cellular signaling.

Antibodies↗