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Biomedical subjects

T Ohtsuka

Publications and source records attributed to T Ohtsuka.

At least 145 records · Page 8Linked to original sources

The relation between nailfold bleeding and capillary microscopic abnormality in patients with connective tissue diseases.

BACKGROUND: Patients with connective tissue diseases, mainly scleroderma, show nailfold bleeding and nailfold capillary abnormality. An attempt was made to determine the possible relation between nailfold bleeding and nailfold capillary abnormality. METHODS: The correlation between nailfold bleeding and nailfold capillary abnormality was studied using quantitative nailfold capillary microscopy. RESULTS: The frequencies of nailfold bleeding in scleroderma, mixed connective tissue disease, dermatomyositis/polymyositis, and secondary Raynaud's phenomenon were significantly higher than those of normal controls. The distributions of abnormal values of capillary parameters in scleroderma, mixed connective tissue disease, dermatomyositis/polymyositis, systemic lupus erythematosus, primary Sjögren's syndrome, secondary Raynaud's phenomenon, primary Raynaud's phenomenon, and diabetes mellitus were significantly higher than those of normal controls. In normal controls, scleroderma, mixed connective tissue diseases, dermatomyositis/polymyositis, systemic lupus erythematosus, primary Sjögren's syndrome, primary Raynaud's phenomenon, and diabetes mellitus, all nailfold bleeding was observed in subjects with nailfold capillary abnormality. The distribution of nailfold bleeding in secondary Raynaud's phenomenon with abnormal values of capillary parameters was significantly higher than that with normal values. CONCLUSIONS: There is a close relationship between nailfold bleeding and nailfold capillary abnormality.

Adolescent↗

Time course of changes in the intestinal permeability of food-sensitized rats after oral allergen challenge.

Rats were sensitized with ovalbumin (OVA) with a molecular weight of 45 kd, challenged with OVA orally, followed by orally administered beta-lactoglobulin (BLG) as an intestinal permeability marker. BLG is a macro-molecular protein with a molecular weight of 18 kd. Blood BLG concentrations were measured (by ELISA) serially over 4 hours following BLG administration, which in turn was given 1 hour after OVA challenges. The maximum BLG concentration was at 2 hours. BLG was then administered orally 1, 3, 6, 12 and 24 hours after oral OVA challenge, and the serum BLG concentration at 2 hours after BLG administration was compared among the five groups. BLG appeared in the circulation of the animals 1, 6 and 24 hours after allergen challenge, but not after 3 and 12 hours. The serum BLG concentration was not significantly different at 1, 6 and 24 hours. Histopathological examinations of the intestines showed mast cell infiltration of the intestinal mucosa at 1 hour, remarkable edema of villi at 3 hours, eosinophil infiltration at 6 hours, an increase of goblet cells at 12 hours and villous atrophy and lymphocyte infiltration at 24 hours. The appearance in the serum of three BLG peaks of comparable heights suggested that the intestinal absorption of BLG may be related to a late and delayed phase as well as the immediate IgE-dependent phase response.

Administration, Oral↗

Life span of skin fibroblasts in patients with systemic sclerosis.

BACKGROUND: It remains unknown whether the life span of systemic sclerosis (SSc) skin fibroblasts (FB) and that of normals are the same or not, though SSc skin FB have been shown to present abnormalities such as elevated collagen synthesis. OBJECTIVE: To find out whether the life span of SSc skin FB and that of normals are the same or not. METHODS: Cell generation and colony-forming efficiency were calculated in 10 normal and 7 SSc FB, and total life spans were studied. RESULTS: Colony-forming efficiency decreased from 30 to 5% until the cells reached senescence. The cell generations of normal and SSc FB showed no significant difference. CONCLUSION: SSc FB is senescent and may indicate that the senescence of SSc FB is independent of its abnormal features.

Adult↗

An early systolic sound associated with midventricular obstruction in a patient with hypertrophic cardiomyopathy.

A 57-year-old woman was admitted for examination because of chest discomfort. Transthoracic echocardiography was performed and she was diagnosed as having hypertrophic cardiomyopathy. An echocardiogram also revealed that she had midventricular obstruction with a pressure gradient of 125 mmHg determined by Doppler echocardiography. A phonocardiogram showed an early systolic sound and the beginning of the sound coincided with the time of septal-posterior wall contact. In addition, the timing also corresponded to the sudden obstruction of blood flow in the region of the midventricular narrowing. Furthermore, this sound markedly decreased with the reduction in pressure gradient caused by cibenzoline treatment. Thus, it was concluded that the early systolic sound was associated with midventricular obstruction and produced by a rapid deceleration of the interventricular flow caused by midventricular obstruction.

Anti-Arrhythmia Agents↗

Increased circulating soluble form of Fas in patients with dilated cardiomyopathy.

To examine the prognostic role of the circulating soluble form of Fas (sFas), circulating sFas levels were measured in 33 patients with dilated cardiomyopathy (DCM) and 12 age-matched normal control subjects (NC) using an enzyme-linked immunosorbent assay (ELISA). Circulating sFas levels in DCM were significantly higher than those in NC (2.42+/-1.02 vs 1.66+/-0.20 ng/ml, p=0.015). Patients with DCM were stratified into 2 groups [group I (n=15): sFas > or =2.06 ng/ml; group II (n=18): sFas <2.06 ng/ml] on the basis of the mean value plus 2SD of circulating sFas level in NC. The circulating sFas level was significantly increased in relation to the severity of heart failure and correlated positively to left ventricular end-diastolic pressure in DCM. However, there were no significant differences in left ventricular dimension between the 2 groups. There were 5 deaths from worsening heart failure in group II, but there were no deaths in group I during the follow-up period. In conclusion, circulating sFas levels were increased in patients with DCM. Circulating sFas levels are increased in proportion to the severity of heart failure and may provide prognostic information independent of left ventricular geometry.

Cardiomyopathy, Dilated↗

Relation between coronary blood flow and left ventricular mass in hypertension: noninvasive quantification of coronary blood flow by thallium-201 myocardial scintigraphy.

This study was conducted to quantify coronary blood flow (CBF) noninvasively according to the fractionation principle and to elucidate the relation between CBF and left ventricular hypertrophy. CBF/cardiac output (CO), estimated on the basis of the ratio of myocardial uptake/total injected dose of thallium-201 (% cardiac uptake), was determined in 14 control subjects and 40 patients with essential hypertension. CBF and CBF per 100 g of myocardium (unit CBF) were calculated according to the following formulas: CBF= % cardiac uptake x CO, and unit CBF = (CBF/LVM) X 100, where CO and left ventricular mass (LVM) are echocardiographically determined. There was good reproducibility of % cardiac uptake (r = 0.983, p < 0.0001). Percent cardiac uptake was greater in hypertensive patients (4.65+/-1.44%) than in control subjects (3.64+/-0.64%), and there was a positive correlation between % cardiac uptake and LVM. CBF (ml/min) was greater in hypertensive patients (240.7+/-80.5) than in control subjects (194.9+/-36.9), but unit CBF (ml/min/100 g) was less in hypertensive patients (102.2+/-26.7) than in control subjects (150.3+/-30.5). Multiple regression analyses showed that LVM was the most potent independent predictor of resting CBF in hypertension. Our results indicate that CBF, determined by thallium-201 myocardial scintigraphy, increases parallel to the increase in LVM, but unit CBF decreases even in the resting condition in patients with essential hypertension.

Adult↗

[Video-assisted mammary harvest technique with harmonic scalpel].

We have developed a video-assisted mammary harvest technique using the Harmonic Scalpel. The clinical method and results are reported here. Since Nov. 1995, 70 left and 5 right internal mammary arteries (L/RIMAs) were taken down thoracoscopically and utilized for minimally invasive coronary artery bypass grafting. Each of the IMAs was harvested up to the upper margin of the first rib or higher and down to the bifurcation. Coagulation and cutting of the branches were achieved with excellent hemostasis using only the Harmonic Scalpel with a hook dissector. A CO2 insufflation technique with 8-10 mmHg of intrathoracic pressure safely improved visualization of the IMA in each case. The mean operative time was 65 minutes (range 45-95) for the left and 35 minutes (range 25-45) for the right. All the pedicled IMAs but one which was lost due to intimal dissection had satisfactory free flows. Video-assisted mammary harvest can be accomplished with insufflation technique and facilitated by using the Harmonic Scalpel with a hook dissector.

Coronary Artery Bypass↗

Marked attenuation of mitral regurgitation by stent implantation: a patient with unstable angina.

A 69-year-old woman was admitted because of increase of chest pain and dyspnea. Systolic murmur of Levine III/VI was heard. Electrocardiography showed ST depression caused by ischemia. Echocardiography revealed severe mitral regurgitation (MR) and inferoposterior hypokinetic wall motion. Left ventriculography revealed the presence of MR (II/IV). Coronary angiography showed severe organic stenosis of the right coronary artery. Based on these findings, the diagnosis was severe papillary muscle dysfunction caused by unstable angina. The lesion of the right coronary artery was successfully stented with a Palmaz-Schatz stent. During balloon inflation, the v wave of the pulmonary capillary pressure curve was greatly elevated. After the stent implantation, ST depression was normalized and MR improved dramatically. Therefore, we suppose that acute MR was induced by temporary papillary muscle dysfunction, and could be relieved with coronary angioplasty.

Aged↗

[Snare injury in coronary artery bypass grafting on the beating heart: report of 2 cases].

From June to November 1997, 8 patients underwent coronary artery bypass grafting on the beating heart. The first 2 patients had snare injury. Postoperative angiography showed coronary stenosis distal to the LITA-LAD anastomosis in the first case and a pseudo-aneurysm at the septal branch of the LAD in the second case, most likely due to snaring maneuver with 3-0 prolene or 3-0 GORE-TEX suture with a sharp needle. Since then, we have been satisfactorily utilizing the RETRACT-O-TAPE (a silicone tape with blunt needle, QUEST Medical, Inc.) for coronary occlusion to avoid injury to the native vessels and their branches.

Angina Pectoris↗

[201T1C1 accumulation dynamics in glioma with different grades of malignancy: an investigation using dynamic SPECT].

Dynamic SPECT was performed using 201TICI in a total of 21 gliomas, 14 cases of glioblastoma multiforme (GM) and 7 cases of anaplastic astrocytoma (AA), to investigate the relationship between test results and malignancy. The accumulation of isotope (counts/pixel) in the tumor was measured every 3 minutes with dynamic SPECT. The initial 3-minute value was reduced from subsequent accumulations (counts/minute) to obtain the time-activity curve (TAC). Thallium index (TL index), the ratio of 15-minute accumulation in the tumor to that in the same region of the contralateral normal brain, was also calculated. TL index was significantly higher (p < 0.05, Mann-Whitney test) in GM (6.25 +/- 1.97) than in AA (4.10 +/- 1.66), although no clear differential value could be determined between the two. TAC in the GM group showed that compared with the initial 3-minute value, accumulation increased significantly (p < 0.05) at every measurement point after isotope injection: 6 minutes, 0.660 +/- 0.671; 9 minutes, 1.322 +/- 1.319; 12 minutes, 1.315 +/- 1.632 and 15 minutes, 1.234 +/- 1.552. The increase in isotope accumulation in the tumor after 6 minutes or later was noted in 11 of the 14 cases in the GM group. In the AA group, however, there were no significant differences between the initial 3-minute value and value after 6 minutes (-0.283 +/- 0.462), 9 minutes (-0.574 +/- 0.681), 12 minutes (-0.690 +/- 0.611) and 15 minutes (-0.707 +/- 0.636) after isotope injection. A decrease in isotope accumulation in the tumor after 6 minutes or later was noted in 6 of the 7 cases in the AA group. Compared with static SPECT, dynamic SPECT, which can be performed easily and quickly, is more useful in clinical settings because of its high ability to differentiate the grade of malignancy of gliomas.

Adult↗

The stiffness of lymph nodes containing lung carcinoma metastases: a new diagnostic parameter measured by a tactile sensor.

BACKGROUND: It is believed that the stiffness or hardness of a lymph node containing a metastasis differs from that of lymph node without a metastasis because of the difference in tissue density, which is derived from the lymph node's histopathologic features. Prior to this study, however, there had been no attempts to quantify the hardness or stiffness of lymph nodes. The authors developed a new tactile sensor and system for measuring the stiffness (g/cm) of lymph nodes accurately, and they studied its utility as a tool for diagnosing lymph node metastases. METHODS: Clinical specimens were obtained from 14 patients who underwent lobectomy or pneumonectomy with hilar and mediastinal lymph node dissection for nonsmall cell lung carcinoma at the University of Tokyo between January and July 1996. With the tactile sensor developed by the authors, 212 resected lymph nodes were measured for their stiffness. RESULTS: Among these 212 resected lymph nodes, 57 were diagnosed as containing metastases (38 from adenocarcinomas and 19 from squamous cell carcinomas). The mean stiffness of the lymph nodes that contained metastases was 3.35 +/- 1.57 g/cm, and that of lymph nodes without metastases was 1.23 +/- 0.50 g/cm (P < 0.001). Receiver operating characteristic analysis revealed that the area under the curve was 0.93, indicating excellent accuracy of the method. When the cutoff was 1.5 g/cm, the sensitivity was 91.2% and the specificity was 78.1% for detection of lymph node metastases. CONCLUSIONS: Measurement of the stiffness of resected lymph nodes was confirmed as an accurate approach to diagnosing lymph node metastases without knowledge of other factors, such as lymph node size or color.

Aged↗

Laser Spectroscopy of Vibration-Rotation Lines in the 3 <-- 0, 5 <-- 0, and 6 <-- 0 Overtones of HBr

The Doppler-limited vibration-rotation absorption spectrum of HBr in the near infrared wavelength region was measured using a GaAs semiconductor laser and a ring-type titanium sapphire laser. About 100 lines in the v = 3 <-- 0, 5 <-- 0, and 6 <-- 0 bands were assigned and 16 Dunham coefficients Y10-Y50, Y01-Y41, Y02-Y22, Y03-Y13, and Y04 for H79Br and H81Br species were determined by a global least-squares fit using the v = 0, v = 1 --> 0, and v = 2 --> 1 lines by V. Braun and P. F. Bernath (J. Mol. Spectrosc. 167, 282-287, 1994), the v = 7 <-- 0 lines by P. Bernage and P. Niay (C. R. Acad. Sci. Paris Ser. B 282, 243-245, 1976), and the v = 3 <-- 0, v = 5 <-- 0, and v = 6 <-- 0 lines by this work. Copyright 1997Academic Press

Journal Article↗

Thoracoscopic internal mammary artery harvest for MICABG using the Harmonic Scalpel.

BACKGROUND: Thoracoscopic internal mammary artery (IMA) harvest is technically demanding, particularly on the left side. We have devised a Harmonic Scalpel (Ethicon Endo-Surgery, Cincinnati, OH) technique to facilitate this procedure, and describe our clinical experience here. METHODS: The Harmonic Scalpel functions with ultrasonic energy, producing less smoke and lower heat than regular electrocautery. A total of 27 (22 left and 5 right) pedicles of the IMA in 23 patients were harvested from the upper margin of the first rib or higher to the lower margin of the fifth rib thoracoscopically using the Harmonic Scalpel with a hook blade. RESULTS: In each case, the IMA harvest was completed thoracoscopically with only the Harmonic Scalpel, decreasing instrument transfers. Each vascular branch was coagulated without charring and was transected with excellent hemostasis. Smokeless views were provided. In the first 17 harvests, Doppler studies 3 months after the procedures demonstrated patent IMAs to the coronary circulation. CONCLUSIONS: The Harmonic Scalpel facilitates thoracoscopic IMA harvest and is expected to minimize hyperthermic damage of the IMA.

Coronary Artery Bypass↗

Identification and localization of an immunoreactive AMPA-type glutamate receptor subunit (GluR4) with respect to identified photoreceptor synapses in the outer plexiform layer of goldfish retina.

L-glutamate, the main excitatory synaptic transmitter in the retina, is released from photoreceptors and evokes responses in second-order retinal neurons (horizontal, bipolar cells) which utilize both ionotropic and metabotropic types of glutamate receptors. In the present study, to elucidate the functional roles of glutamate receptors in synaptic transmission, we have identified a specific ionotropic receptor subunit (GluR4) and determined its localization with respect to photoreceptor cells in the outer plexiform layer of the goldfish retina by light and pre-embedding electron-microscopical immunocytochemistry. We screened antisera to mammalian AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate)-preferring ionotropic glutamate receptors (GluR 1-4) of goldfish retina by light- and electron-microscopical immunocytochemistry. Only immunoreactive (IR) GluR4 was found in discrete clusters in the outer plexiform layer. The cones contacted in this manner were identified as long-wavelength ("red") and intermediate-wavelength ("green") cones, which were strongly immunoreactive to monoclonal antibody FRet 43 and antisera to goldfish red and green-cone opsins; and short-wavelength ("blue") cones, which were weakly immunoreactive to FRet 43 but strongly immunoreactive with antiserum to blue-cone opsin. Immunoblots of goldfish retinal homogenate with anti-GluR4 revealed a single protein at M(r) = 110 kDa. Preadsorption of GluR4 antiserum with either the immunizing rat peptide, or its goldfish homolog, reduced or abolished staining in retinal sections and blots. Therefore, we have detected and localized genuine goldfish GluR4 in the outer plexiform layer of the goldfish retina. We characterized contacts between photoreceptor cells and GluR4-IR second-order neurons in the electron microscope. IR-GluR4 was localized to invaginating central dendrites of triads in ribbon synapses of red cones, semi-invaginating dendrites in other cones and rods, and dendrites making wide-cleft basal junctions in rods and cones; the GluR4-IR structures are best identified as dendrites of OFF-bipolar cells. The results of our studies indicate that in goldfish retina GluR4-expressing neurons are postsynaptic to all types of photoreceptors and that transmission from photoreceptors to OFF-bipolars is mediated at least in part by AMPA-sensitive receptors containing GluR4 subunits.

Amino Acid Sequence↗