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T Ichihara

Publications and source records attributed to T Ichihara.

At least 127 records · Page 7Linked to original sources
PubMed1993

[A study of myocardial disorders in an autopsy case of mitochondrial encephalomyopathy].

We report an autopsy case of a 19 year-old man with MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) a subgroup of mitochondrial encephalomyopathy presenting cardiomyopathy. He had repeatedly suffered from transient unconsciousness, hemiplegia, hemianopsia and convulsion attacks since the age of 9, and he died of severe congestive heart failure. In laboratory findings, blood lactate and pyruvate were markedly increased. Skeletal muscle biopsy demonstrated numerously scattered ragged-red fibers with modified Gomori's trichrome staining. Enzymatic activities of the mitochondrial respiratory chain showed a marked decrease of NADH cytochrome c reductase (complex I). In postmortem examination, the heart was 310g in weight and had right ventricular dilatation. Microscopically, degenerated and scattered myocardial cells (ragged-red fibers), interstitial edema and microvascular hyperplasia were demonstrated in the myocardium. Under the electron microscope, abnormal mitochondria proliferated and myofibrils were unusually sparse. Immunohistochemical studies with specific antibodies against the mitochondrial electron transfer enzyme subunits revealed a reduction of immunoreactive materials for complex I in the myocardium. These results suggested the relationship of myocardial disorders and decreased activity of complex I in electron transfer enzymes in this patient.

Adult↗
PubMed1992

Serial change of iodine-123 metaiodobenzylguanidine (MIBG) myocardial concentration in patients with dilated cardiomyopathy.

Serial change of the metaiodobenzylguanidine iodine-123 (123I-MIBG) myocardial concentration was investigated in patients with dilated cardiomyopathy (DCM). Eight DCM patients and 6 control subjects were examined. After the injection of thallium-201 and 123I-MIBG, planar chest images were obtained simultaneously for both tracers in every 30-60 min over 5 h. Serial changes of myocardial uptake ratio (MUR) were compared for both tracers. In DCM, the initial MUR of 123I-MIBG did not differ significantly from that of the controls. The washout of 123I-MIBG from the myocardium, however, was significantly increased in DCM. In particular, the decrease in the early phase (15-45 min) was significantly larger in DCM than in the controls (21.2% +/- 7.5% vs. 5.3% +/- 4.0%, P less than 0.01), showing a significant negative correlation with the left ventricular ejection fraction (r = -0.72 P less than 0.05). For 201Tl, neither the initial MUR nor the washout rate different significantly between the two. Thus, an early rapid decrease of the 123I-MIBG myocardial concentration might characterize DCM and reflect the severity of this disease.

3-Iodobenzylguanidine↗
PubMed1992

T-cell-dependent production of IgG by human cord blood B cells in reconstituted SCID mice.

Reconstitution of severe combined immunodeficient (SCID) mice with human lymphocytes has recently allowed the elucidation of abnormalities of immune responses in various immunological disorders. In the present study, mononuclear cells (MNC) from neonatal cord blood and adult peripheral blood were intraperitoneally injected into SCID mice to examine induction of human Ig in respective mice recipients. Human IgG was consistently detected in the serum of SCID transferred with adult MNC, but only a few SCID recipients of cord blood MNC showed detectable but low levels of IgG in the serum. The combination experiments of isolated B and T cells disclosed that some interactions between B and T cells might be necessary for IgG production in transferred SCID mice. Notably, transfer of cord blood B cells with adult but not cord blood T cells resulted in efficient induction of IgG, associated with a change in subclass distribution. The results suggest that inability of neonatal B cells to produce IgG can be overcome by transfer with adult mature T cells into SCID mice.

Animals↗
PubMed1992

[Problems and prevention in using arterial grafts for coronary artery bypass grafting].

The arterial graft has proved to be superior to the saphenous vein graft for coronary bypass grafting (CABG), because of its excellent long-term patency. However, there mains controversial on the choice of the arterial grafts. Six hundreds and twenty seven patients who had CABG using both arterial grafts and saphenous vein grafts, operated upon over 11-years period between 1980 and 1991, have been analysed. Some disadvantages and complications associated with the use of arterial grafts were demonstrated in our series. We discussed, the flow capacity, myocardial protection and postoperative complications in using arterial grafts for CABG.

Aged↗
PubMed1992

[A case report on the sliding commissuroplasty for mitral regurgitation due to posterior commissural chordal rupture].

We have performed a mitral valve reconstruction on a 31-year-old man who suffered from infective endocarditis four years ago. Severe mitral regurgitation and posterior commissural chordal rupture were noted. The mitral valve was repaired by Carpentier's sliding commissuroplasty and ring annuloplasty. The postoperative course was uneventful, and mitral regurgitation completely disappeared. It appears that Carpentier's sliding commissuroplasty is a superior new reconstructive technique for mitral regurgitation due to commissural chordal rupture.

Adult↗
PubMed1992

High-resolution cardiac SPET study using fanbeam collimators in infants.

High-resolution three-headed single photon emission computed tomography (SPET) equipped with fan-beam collimators was applied to myocardial perfusion imaging in infants aged from 1 to 11 months (n = 5). A tabletop designed specifically for infants was fixed on the SPET couch to reduce the radius of camera rotation to 13.2 cm. Significant improvement in resolution was achieved with the fan-beam collimators compared to parallel-hole high-resolution collimators. With the administration of approximately 37 MBq (26-44 MBq) 201Tl, 5 min acquisition time was possible for SPET imaging, which provided good image quality in all patients. Thus, a smaller administration dose is possible within a practical short acquisition time. High-resolution fan-beam SPET imaging can be a routine diagnostic method for heart disease in newborn babies and infants.

Female↗
PubMed1992

A simulation of dynamic SPECT using radiopharmaceuticals with rapid clearance.

Data acquisition in SPECT assumes that there is no change in radionuclide distribution during data collection. However, this assumption is not valid in radiopharmaceuticals with rapid temporal changes in radioactivity. Artifacts and quantitative errors are studied using phantom studies, mathematical models, and clinical myocardial data. Projection data of each model were sequentially multiplied by weighting coefficients that varied mono-exponentially with time, and the SPECT images were reconstructed. A long data acquisition time in comparison to the clearance of the tracer can be a significant cause of artifact. When the myocardial septum-to-lateral count ratio is used as an index of distortion, a shorter acquisition time than the effective half-life of the tracer is required to reduce the error of the septum-to-lateral count ratio to within 10%. Since 180 degrees rotation acquisition causes artifacts depending on the direction of rotation, 360 degrees acquisition is preferable. Continuous repetitive rotation acquisition is a suitable method for dynamic SPECT to reduce quantitative errors and artifacts.

Artifacts↗
PubMed1991

A new approach to chemoembolization for unresectable hepatocellular carcinoma using aclarubicin microspheres in combination with cisplatin suspended in iodized oil.

Sixty-six consecutive patients with unresectable hepatocellular carcinoma (HCC) were treated with transcatheter arterial chemoembolization (TACE) using aclarubicin microspheres (ACRms) in combination with cisplatin suspended in iodized oil (Lipiodol, Laboratoire Guerbert, Paris, France) (CSL). The stages of the disease were as follows: Stage I (n = 1), Stage II (n = 10), Stage III (n = 26), and Stage IV (n = 29). The effectiveness of TACE was assessed by comparing ACRms with CSL with ACRms without CSL. Of 66 patients treated with ACRms and CSL, 62 (93.9%) could be examined for response. According to response criteria, there were 31 (50.0%) partial responses and 17 (27.4%) minor responses. In 13 cases (21.0%) there was no change and in 1 case (1.6%) there was progressive disease. The cumulative survival rate was 80.7% at 1 year, 64.2% at 2 years, and 50.6% at 3 years. The rates were significantly higher than those of the group treated with ACRms. Eleven patients in the ACRms and CSL group experienced clinical complications: cholecystitis (4.5%), pancreatitis (3.0%), liver abscess (3.0%), hepatic failure (3.0%), gastrointestinal bleeding (1.5%), and renal failure (1.5%). No lethal side effects related to the therapy were observed. TACE using ACRms in combination with CSL prolongs the survival of patients with unresectable HCC.

Aclarubicin↗
PubMed1991

Structure of benzyloxycarbonyl-L-isoleucyl-L-alanyl-alpha- aminoisobutyryl-alpha-aminoisobutyrate methyl ester, Z-L-Ile-L-Ala-Aib-Aib-OMe.

C26H40N4O7, Mr = 520.6, tetragonal, P4(3)2(1)2, a = 10.433 (1), c = 54.476 (7) A, V = 5930 (1) A3, Z = 8, Dm = 1.155 (3), Dx = 1.166 Mg m-3, lambda (Cu K alpha) = 1.54178 A, mu = 0.665 mm-1, F(000) = 2240, T = 295 K, R = 0.057 for 2037 observed reflections. The tetrapeptide adopts a type II beta-turn conformation with an extremely weak 4----1 intramolecular hydrogen bond [3.479 (7) A]. The molecules are held together in the crystal by three kinds of N-H---O intermolecular hydrogen bonds.

Amino Acid Sequence↗
PubMed1991

Serum concentration and immunohistochemical localization of SPan-1 antigen in pancreatic cancer. A comparison with CA19-9 antigen.

We studied SPan-1 antigen in 64 patients with pancreatic cancer by measuring serum concentrations with RIABEAD and examining the intratumor staining patterns immunohistochemically. Serum concentrations were elevated (greater than 30 U/ml) in 46 patients (72.0%), roughly the same percentage as with elevated serum CA19-9 concentrations. Ten out of 19 patients without CA19-9 antigen expressed SPan-1, and the combined rate of positivity was 86% (55/64). Immunohistochemically, CA19-9 was localized to the apical surface and the supranuclear cytoplasm of normal epithelial cells, but SPan-1 was localized to the supranuclear cytoplasm or throughout the cytoplasm. After malignant degeneration, both antigens were found over the entire plasma membrane, throughout the cytoplasm (loss of polar distribution) and in the stroma surrounding the cells. SPan-1 was detected in 48 out of 54 adeno-carcinomas of the pancreas (89%), and all cases with an elevated serum concentration displayed stromal staining in the cancer tissues. The utility of SPan-1 antigen as a tumor marker for diagnosing pancreatic cancer was found to be equal to that of CA19-9.

Adenocarcinoma↗
PubMed1991

[A treatment of intractable sternal osteomyelitis--significant use of pedicle muscular flaps].

In recent years, the greater omentum of pedicle muscular flap has been used to treat chest wall infection and Sternal Osteomyelitis following cardiac or respiratory surgery. In Japan, however, there has been an increasing number of cases in which neither the greater omentum Nor the rectus muscle can be used due to the comparatively young age of the patient. There are also many cases undergoing abdominal surgery for malignant tumor and bypass surgery of the coronary artery in which the internal thoracic artery (ITA) and gastroepiploic artery (GEA) are used. We studied three such cases; a case of coronary aortic bypass graft (CABG) where ITA from both the right and left sides were used following stomach resection; a case in which CABG and gallbladder resection were carried out simultaneously; and a case of sternal osteomyelitis is years following surgery for ventricular septal defect. All three cases had undergone reconstructive surgery using the pectoralis major muscle or a pedicle muscular flap from the latissimus dorsi muscle. It is estimated that cases of CABG using both the right and left sides of ITA and GEA, cases of the elderly as well as cases of children will continue to increase. Consequently, cases of sternal osteomyelitis in which neither the omentum nor rectus muscle can be used will also increase. Therefore, it is considered that treatment using pedicle muscular flaps from the breast or dorsal area may be very effective. Herein, we report on the choice of treatment and its results.

Aged↗
PubMed1991

[Carbohydrate antigens as a tumor-associated antigen and prognostic indicators in carcinomas of the breast, esophagus, stomach, colorectum, and pancreas].

The immunohistochemical analysis using the monoclonal antibodies to the carbohydrate antigens were performed and suggested that CA19-9 is a tumor-associated antigen in gastric cancer, Leb, Ley, CA19-9, CSLEX1, SLX in colorectal cancer and pancreatic cancer, and Lex, Ley, and CSLEX1 in breast and esophageal cancers, respectively. Expression of the type 2 carbohydrate antigens had relation to the prognosis of patients with breast cancer. In colorectal cancer, the patients with high degree of expression of CA19-9 had a poor prognosis, and high risk of distant metastasis. Higher intensity of staining was observed in hepatic in comparison with primary lesion. Thus carbohydrate antigens showed important role as tumor-associated antigens and good indicator for evaluation of prognosis.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1991

Dynamic acquisition with a three-headed SPECT system: application to technetium 99m-SQ30217 myocardial imaging.

A method for SPECT data acquisition, "continuous repetitive rotation acquisition," was developed with a high-sensitivity three-headed SPECT system. The method was applied to the dynamic imaging of 99mTc-SQ30217, a new myocardial imaging agent. After acquisition and reconstruction of SPECT data every minute, projection images at arbitrary intervals were used for tomographic reconstruction to determine the best timing of SPECT imaging in 99mTc-SQ30217. Based on a comparison of several possible acquisition intervals, SPECT data acquisition within 9 min after injection is recommended because of high myocardial uptake (myocardium-to-lung ratio, 2.83 +/- 0.42 (mean +/- s.e.m.) at 3-6 min) and relatively low hepatic uptake (myocardium-to-liver ratio, 0.85 +/- 0.13 at 3-6 min). The rate constant of the clearance of 99mTc-SQ30217 from the myocardium obtained by SPECT was: k1 = 0.249 +/- 0.050 per min (average half-life = 2.8 min) and k2 = 0.012 +/- 0.004/min (average half-life = 58 min). The continuous repetitive rotation acquisition SPECT study appears useful for imaging SQ30217 with its rapidly changing myocardial distribution.

Adult↗
PubMed1991

[Myocardial perfusion imaging with 99mTc-SQ30217: application of three-headed SPECT system].

The early dynamic change of a new myocardial imaging agent, 99mTc-SQ30217, was investigated in SPECT study. A three-headed high sensitivity SPECT system was employed to evaluate the serial changes of accumulation pattern in the heart, lung and liver using a "continuous repetitive acquisition" mode. The myocardial activity reached a peak rapidly and decreased with rapid clearance rate. The analysis of myocardial clearance curve showed a T1/2 of 2.8 minutes (k1 = 0.25 +/- 0.12/min) in the rapid phase, and a T1/2 of 57 minutes (k2 = 0.012 +/- 0.011/min) in the slow phase. The tracer clearance in the lung was more rapid, while the hepatic uptake reached a peak approximately 10 to 15 minutes after injection. When the serial SPECT images were reviewed, the early 3-minute acquisition within 10 minutes after injection showed better image quality than the images obtained after 10 minutes. The hepatic activity did not obscure the infero-septal wall in the earlier images, but did in the images 10 minutes after injection. Thus, quick SPECT data acquisition seemed to be desirable for this agent. We concluded that 99mTc-SQ30217 was a promising radiopharmaceutical for myocardial perfusion imaging.

Aged↗
PubMed1990

Coronary artery bypass in a 15-year-old girl with pseudoxanthoma elasticum.

A 15-year-old girl with pseudoxanthoma elasticum and associated severe coronary artery disease underwent double coronary artery bypass using left internal mammary artery and saphenous vein. Preoperatively the patient had life-threatening syncope and positive treadmill test results. The postoperative course was uneventful, and the patient has been doing well for 3 years. Pseudoxanthoma elasticum is a rare disease that can cause premature coronary arterial obstructive disease in children and adolescents.

Adolescent↗