Search PubMed⌕ Search

Biomedical subjects

T Ota

Publications and source records attributed to T Ota.

At least 181 records · Page 10Linked to original sources
PubMed1996

[Clinical usefulness of trans-brachial angiography for abdominal diseases].

Trans-brachial angiography for abdominal disease has several advantages for the patient. For example, the patient can walk immediately following angiography and can return home or eat in the sitting position after examination. We performed trans-brachial angiography on 451 cases of abdominal disease from June 1992 to March 1995. The purpose of performing angiography in 215 of these cases was examination only, while that in the remaining 236 cases was embolization of liver tumor. Four hundred and five cases were used for the study of safety and accuracy, and the remaining 46 cases as well as another 51 cases of trans-femoral angiography were used for the study of technical difficulty. Based on these experience, we have concluded that trans-brachial angiography for abdominal disease is highly useful, safe and accurate, and can provide significant advantages for patients requiring abdominal angiography.

Adult↗
PubMed1996

[A case of surgically treated left atrial myxoma early after cerebral embolism].

A 48-year-old female had been visiting the outpatient clinic for treatment of polyarthritis before she was admitted to the hospital due to consciousness disorder and right hemiplegia. Brain computed tomography revealed a small infarction in the left cerebrum. Echocardiography revealed a mass in the left atrium. She was diagnosed cerebral embolism caused by left atrial myxoma. Extirpation of left atrial myxoma was performed 16 days after the onset of cerebral infarction. The postoperative course was good. Preoperative constitutional signs such as multiple arthralgia and abnormal sensation disappeared on the 2nd postoperative day. Open heart surgery performed early after the onset of cerebral embolism is generally considered contraindicated due to problems of hemorrhagic infarction or brain edema. Because relapse of embolism may deteriorate the condition, losing the chance of surgery, extirpation of left atrial myxoma early after the onset of cerebral infarction is advisable in cases of small infarction.

Female↗
PubMed1996

Age-related change of technetium-99m-HMDP distribution in the skeleton.

UNLABELLED: To understand age-related changes of whole-body and regional skeletal metabolism, it is important to investigate the mechanisms of age-related bone loss and to develop suitable treatments for it. Bone biopsies show metabolism of the particular site examined while biochemical markers for bone metabolism reflect total skeletal metabolism. Bone scintigraphy is a convenient and simple way to analyze whole-body and regional skeletal metabolism. We attempted to study and understand age-related changes in bone metabolism by quantifying the bone scan and correlating it with biochemical bone metabolic markers. METHODS: The whole-body skeletal uptake (WBSU) and tracer distribution pattern were studied in men and women by bone scintigraphy using 99mTc-hydroxy-methane-diphosphonate (HMDP). Bone scans were performed using a standard protocol and quantified by setting regions of interest (ROIs) on selected regions. WBSU and the skeletal distribution pattern were compared with simultaneously obtained serum biochemical markers. RESULTS: WBSU showed an increase with age in both sexes, but in women, uptake in the head and legs increased more relatively than in the thoracic region, while in men no such tendency was observed. Increase of WBSU and relative increase of uptakes in the head demonstrated a weak correlation with the serum levels of alkaline phosphatase and type 1 collagen metabolites. CONCLUSION: These results show an age-related increase of skeletal turnover and sex-dependent regional skeletal metabolism. The age-related changes seen in bone scintigrams might be a sign of progressive bone loss, reflecting changes in local bone metabolism.

Age Factors↗
PubMed1995

Biochemical analysis of ferritin subunits in sera from adult Still's disease patients.

To determine the origin of the increased serum ferritin that occurs in adult Still's disease (ASD), we analyzed subunits of the serum ferritin as follows. Gel filtration with Sepharose CL-6B demonstrated that the molecular weight of serum ferritin was about 490 kDa. Western blot analysis revealed only L-subunits (molecular weight 19 kDa) in patients with serum ferritin levels higher than 1,000 ng/ml. Patients with serum ferritin levels higher than 1,000 ng/ml, however, showed G-subunits (molecular weight 23 kDa) in addition to the L-subunits. When concanavalin A (Con-A) Sepharose 4B was used in an absorption test, the percentage absorption was extremely low in the patients with serum ferritin levels higher than 1,000 ng/ml. Isoferritin patterns of the patients determined by chromatofocusing revealed traces of acidic ferritin. The findings suggested that glycosylated ferritin does not account for the major portion of the increased serum ferritin.

Adult↗
PubMed1995

Acute left atrial thrombus causing cardiogenic shock following mitral valve replacement: report of a case.

We report herein the rare case of a 53-year-old woman who developed cardiogenic shock due to an acute left atrial thrombus following replacement of the mitral valve. A definitive diagnosis was not able to be made using precordial echocardiography because of the broad, flat shape of the thrombus; however, transesophageal echocardiography imaged the thrombus in detail. The patient was initially stabilized by percutaneous cardiopulmonary support after which a thrombectomy was successfully performed.

Echocardiography, Transesophageal↗
PubMed1995

Fluorodeoxyglucose positron emission tomography in pancreatic cancer: an unsolved problem.

The aim of this study was to examine the significance and problems of 2-[fluorine-18]-2-deoxy-d-glucose (FDG) positron emission tomography (PET) in diagnosing pancreatic cancer and mass-forming pancreatitis (MFP). PET, X-ray computed tomography (CT) and magnetic resonance (MR) imaging were performed in 15 patients with pancreatic cancer and nine patients with MFP. The areas of the PET scan were determined according to the markers drawn on the patients at CT or MR imaging. Regions of interests (ROIs) were placed by reference to the CT or MR images corresponding to the PET images. Tissue metabolism was evaluated by the differential absorption ratio (DAR) at 50 min after intravenous injection of FDG [DAR = tissue tracer concentration/(injected dose/body weight). The DAR value differed significantly in pancreatic cancer (mean +/- SD, 4.64 +/- 1.94) and MFP (mean +/- SD, 2.84 +/- 2.22) (P < 0.05). In one false-negative case (mucinous adenocarcinoma), the tumour contained a small number of malignant cells. In one false-positive case, lymphocytes accumulated densely in the mass in the pancreatic head. Further studies are necessary to investigate the histopathological characteristics (especially the cellularity) and other factors affecting the FDG DAR on PET images.

Adenocarcinoma↗
PubMed1995

Usefulness of femoro(ilio)-axillar bypass surgery for the treatment of subclavian steal syndrome caused by aortitis syndrome.

In two patients with subclavian steal syndrome associated with aortitis syndrome, retrograde bypass grafting from the femoral or common iliac artery to the axillary artery resulted in the disappearance of symptoms. One patient, a 37-year-old female, was treated with a bypass from the left femoral artery to the left axillary artery with a 10-mm ring-supported double velour knitted Dacron graft. The other patient, a 54-year-old female, with the complication of moderate aortic regurgitation, was treated with a bypass from the left common iliac artery to the left axillary artery with an 8-mm EPTFE graft. These bypass grafts were angiographically confirmed to be patent after the operation. When changes in graft flow in different body positions (supine, sitting, and standing) were examined, using a transcutaneous Doppler flow meter, 5 years after the operation, resting graft flow to the upper extremities showed no consistent changes among the three different positions and was maintained in a stable condition, regardless of the patients' positions. Furthermore, graft flow increased while the left arm exercised. This finding, together with the clinical efficacy, indicates that this mode of retrograde bypass grafting may be effective in some selected patients with this complicated syndrome.

Adult↗
PubMed1995

Electroporation-mediated transfection of mammalian cells with crude plasmid DNA preparations.

We designed a simple and reproducible electroporation-mediated transfection procedure with which to screen mammalian expression vector-constructed cDNA libraries. Using a specific chamber composed of five parallel electrodes, the recipient cells can be electroporated separately with 40 plasmid DNA preparations in a single experiment. Over 300 crude plasmids prepared from E. coli (DH-5) carrying a pcD2neo-vector-derived cDNA library were tested. The efficiency of stable transfection by electroporation with crude plasmid DNA preparations was 10-times higher than with the CsCl-purified plasmid DNA. When the crude plasmids were digested with RNase, the efficiency of stable transfection markedly decreased, indicating that the contaminating bacterial RNA in the crude plasmid preparations has a strong carrier effect during the electroporation. Even when salmon sperm DNA or genomic DNA from the recipient cells was used as the carrier of the purified plasmid, the efficiency was not higher than that using the crude preparations. This procedure is useful not only for screening a number of cDNAs but also for routinely introducing biologically active foreign genes into cultured mammalian cells.

3T3 Cells↗
PubMed1995

Pharmacologic intervention for ischemic brain edema after retrograde cerebral perfusion.

Retrograde cerebral perfusion has recently been the focus of interest as a simple new technique of brain protection during aortic arch operations. We undertook the experimental protocol of 120 minutes of retrograde cerebral perfusion followed by antegrade reperfusion. Eighteen mongrel dogs were used. Retrograde cerebral perfusion was maintained at a flow rate of 150 to 250 ml/min to keep the perfusion pressure from 15 to 25 mm Hg. Animals were divided into three groups as follows: in group I, no treatment was received during and after retrograde cerebral perfusion; in group II, mannitol (2 gm/kg) was administered before cardiopulmonary bypass was restarted; and in group III, antivasospastic substance (1,2-bis nicotinamido]-propane) was continuously injected during and after retrograde cerebral perfusion (1 mg/kg per minute). Cerebral blood flow decreased during retrograde cerebral perfusion in all three groups. Cerebrovascular resistance showed marked increases 30 and 60 minutes after cardiopulmonary bypass was restarted in group I compared with the values in groups II and III (group I: 3.35 +/- 0.73 and 5.00 +/- 1.57 mm Hg/ml per 100 gm per minute; group II: 1.30 +/- 0.33 and 1.03 +/- 0.17 mm Hg/ml per 100 gm per minute; group III: 1.24 +/- 0.41 and 0.98 +/- 0.24 mm Hg/ml per 100 gm per minute). The oxygen extraction level was reduced by cooling, but it rose to a higher level as a result of significant desaturation of returned blood even in deep hypothermia during retrograde cerebral perfusion. Both cerebral metabolic rate of oxygen and cerebral metabolic rate of glucose remained at low levels during retrograde cerebral perfusion. Ratios of cerebral blood flow to cerebral metabolic rate of oxygen and cerebral blood flow to cerebral metabolic rate of glucose were markedly reduced during retrograde cerebral perfusion. Intracranial pressure showed significant increases 30 and 60 minutes after cardiopulmonary bypass was restarted in group I compared with values in group II or group III (group I: 22.7 +/- 2.8 and 20.6 +/- 5.1 mm Hg; group II: 6.3 +/- 1.8 and 5.3 +/- 1.3 mm Hg; group III: 4.2 +/- 1.7 and 7.7 +/- 2.8 mm Hg). Water content of the brain tissue in group I (77.54% +/- 0.29%) was significantly higher than that in group II (74.71% +/- 0.76%) or group III (74.14% +/- 0.48%). These data suggest that the supply of oxygen or glucose by retrograde cerebral perfusion is not enough to maintain sufficient cerebral metabolism, which may cause brain edema during antegrade reperfusion.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1995

Evolution of immunoglobulin VH pseudogenes in chickens.

In chickens, there is a single functional gene (VH1) coding for the heavy chain variable region of immunoglobulins, and immunoglobulin diversity is generated by gene conversion of the VH1 gene by many variable region pseudogenes (psi VH's) that exist on the 5' side of the VH1 gene. To understand the evolution of this unique genetic system, we conducted statistical analyses of VH1 and psi VH genes together with functional VH genes from other higher vertebrate species. The results indicate, first, that chicken VH genes are all closely related to one another and were derived relatively recently from an ancestral gene belonging to one of the three major groups of VH genes in higher vertebrates. Second, the rate of nonsynonymous substitution is slightly higher than that of synonymous substitution in the complementarity-determining regions (CDRs), which suggests that diversity-enhancing selection has operated in the CDRs even for pseudogenes. However, both the rates of synonymous and nonsynonymous substitution are higher in the CDRs than in the framework regions (FRs), apparently because of an interaction between positive selection and meiotic gene conversion in the CDRs. Third, a dot matrix analysis of the psi VH genes and genomic diversity (D) genes has indicated that the 3' end of psi VH genes is attached by D-gene-like sequences, and this region of psi VH genes has high similarity with D gene sequences. This suggests that V and D genes were fused at some point of evolutionary time and this fused element multiplied by gene duplication. Finally, two alternative hypotheses of explaining the evolution of the chicken VH gene system are presented.

Animals↗
PubMed1995

Positive selection is a general phenomenon in the evolution of abalone sperm lysin.

Lysin is a 16kDa acrosomal protein used by abalone sperm to create a hole in the egg vitelline envelope (VE). The interaction of lysin with the VE is species-selective and is one step in the multistep fertilization process that restricts heterospecific (cross-species) fertilization. For this reason, the evolution of lysin could play a role in establishing prezygotic reproductive isolation between species. Previously, we sequenced sperm lysin cDNAs from seven California abalone species and showed that positive Darwinian selection promotes their divergence. In this paper an additional 13 lysin sequences are presented representing species from Japan, Taiwan, Australia, New Zealand, South Africa, and Europe. The total of 20 sequences represents the most extensive analysis of a fertilization protein to date. The phylogenetic analysis divides the sequences into two major clades, one composed of species from the northern Pacific (California and Japan) and the other composed of species from other parts of the world. Analysis of nucleotide substitution demonstrates that positive selection is a general process in the evolution of this fertilization protein. Analysis of nucleotide and codon usage bias shows that neither parameter can account for the robust data supporting positive selection. The selection pressure responsible for the positive selection on lysin remains unknown.

Amino Acid Sequence↗
PubMed1995

Polysialogangliosides expressed by amelanotic melanoma: a possible explanation for the poor response to anti-monosialoganglioside antibody 202 in a patient with melanoma.

A 52-year-old Japanese woman developed numerous amelanotic metastatic melanomas on the skin and in various organs three years after a surgical operation for primary melanoma on the right axilla. The patient was treated with monosialoganglioside specific monoclonal antibody 202; however, no apparent clinical effects were observed. Ganglioside analysis of a metastatic tumor demonstrated that it expressed GM3, GM2, GD3, GD2, and polysialogangliosides. Since polysialogangliosides rarely appear in melanomas, their expression may explain the patient's poor response to MAb 202. The relationship between ganglioside composition and the effect of anti-ganglioside monoclonal antibody is discussed.

Antibodies, Monoclonal↗
PubMed1995

Reduction of left ventricular hypertrophy with St. Jude Medical 19 mm valve prosthesis.

To determine the permissible range of the St. Jude Medical 19 mm valve (SJM19) as an aortic prosthesis, transvalvular maximal pressure gradient (maxPG) and postoperative reduction of left ventricular (LV) hypertrophy were examined in 21 patients (body surface area [BSA] 1.28-1.56 m2, mean 1.42 m2). Doppler echocardiographically measured maxPG at rest was 31 +/- 16 mmHg, which showed no significant difference from the differences in patients' diseases (aortic regurgitation = AR or stenosis = AS), or BSA. The maxPG, also measured during dobutamine administration when they were less than 40 mmHg at rest, increased significantly from 21 +/- 11 mmHg to 32.1 +/- 15 mmHg, having no differences from the differences in diseases or BSA. Reduction of LV hypertrophy was achieved postoperatively (mean postoperative period of ten months), with the reduction rates of 26 +/- 19% in LV mass and 21 +/- 15% in LV cross-sectional area. No significant differences were found between the reduction rates and the differences in the patients' diseases or BSA. These results indicate that, following the implantation of SJM19, LV hypertrophy was reduced in patients with AR as well as with AS, when their BSA values were less than 1.6 m2. However, limited use is recommended because the increase in pressure gradient during exercise cannot be ignored.

Adult↗
PubMed1995

Immunohistological reaction mechanism of anti-monosialoganglioside monoclonal antibody, MAb 202, showing predominant cytotoxicity for malignant melanoma.

Mouse monoclonal IgM antibody (MAb 202) can cause melanoma cell necrosis in vivo. We analysed its immune mechanism in three melanoma patients to whom MAb 202 was administered. After the MAb 202 administration, histopathological analysis showed necrosis of melanoma cells expressing only GM3 in two patients. Another patient carrying both GM3 and GD3 showed infiltration of lymphocytes within the tumor nest but no tumor cells or nest necrosis. Immunohistological examination using anti-mouse IgM antibody revealed MAb 202 bound on the surface of melanoma cells in two patients but not in the third (positive for both GM3 and GD3). In vitro, MAb 202 reacted with the melanoma cells of the same two patients, but not with any other tissues of these individuals. We found no reaction of MAb 202 to non-melanoma cells including normal melanocytes and glia cells. Our trials suggest, 1) MAb 202 reacts directly to monosialogangliosides on the melanoma cell surface and then leads to the cytotoxicity reaction, or 2) MAb 202 induces lymphocyte infiltration and possibly then promotes the secretion of some cytokines.

Adult↗
PubMed1995

Periodic angioedema with eosinophilia: increased serum level of interleukin 5.

A 48-year-old man developed episodic non pitting edema and eosinophilia. Symptoms were alleviated promptly when treated with prednisolone. However, major basic protein (MBP), eosinophil cationic protein (ECP), and eosinophil-derived neurotoxin (EDN) levels in the serum as well as the total number of eosinophils remained high. During periods of attack serum levels of interleukin-5 (IL-5) were elevated, but the levels were lowered following treatment, suggesting that IL-5 is involved in periodic angioedema with eosinophilia.

Angioedema↗
PubMed1995

Sjögren's syndrome terminating with multiple myeloma.

We describe a patient (49 years old, female) with a more than 7-year history of both Sjögren's syndrome (SjS) and benign monoclonal gammopathy (BMG) of IgG lambda who later developed multiple myeloma (MM). SjS is frequently complicated with malignant lymphoproliferative disorders, especially malignant lymphoma or Waldenström's macroglobulinemia. Association of SjS with MM seems to be extremely rare, although BMG has been observed frequently in SjS, and there are many reports concerning the association between rheumatoid arthritis and MM.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

[Use of epicardial leads for transvenous pacing lead insufficiency with venous thrombosis: a case report].

Recent progress in the electrode tip to prevent dislodgement makes difficult to extract itself in some patients. And when multiple leads are placed through a transvenous route, more frequent occurrence of venous thrombosis is easily suspected. We experienced a case of transvenous lead insufficiency with venous thrombosis. In this patient, two of unextractable transvenous leads were already placed, and venous thrombosis was detected by venography, so we implanted the new epicardial leads instead. In case of long-term placement of transvenous leads, especially when multiple, the possibility of venous thrombosis is ever thought, and the use of the extractable leads or anticoagulant therapy is recommended.

Aged↗