Biomedical subjects

T Tashiro

Publications and source records attributed to T Tashiro.

At least 199 records · Page 11Linked to original sources

PubMed1993

[Parapsoriasis en plaque suspected of progression to mycosis fungoides associated with extranodal malignant B cell lymphoma of the cheek].

A 59-year-old female, clinically diagnosed as having parapsoriasis en plaque for ten years, was referred on June 1991 to the Department of Oral Surgery in the Dental School of showa University with a complaint of painless swelling of the left malar area. The swelling was found to have been caused by a tumor. Since the excised tumor was suspected to be a malignant lymphoma, she was admitted to our hospital. The specimen was subsequently confirmed to be a malignant lymphoma of the diffuse large cell type according to the LSG classification, and was immunologically confirmed to be a B cell lymphoma. In addition, the excised skin was suspected of incipient mycosis fungoides. She was classified as having stage IE disease according to her bone marrow biopsy and other examinations. she was treated with combination of chemotherapy (CHOP) and radiation therapy. This subject was interesting because her tumor probably resulted from a parapsoriasis en plaque skin lesion.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1993

[Clinical experience with continuous warm blood cardioplegia].

We applied the Continuous Warm Blood Cardioplegia (CWBC) as an approach to improve myocardial preservation. From March to June in 1992, we used the CWBC in six patients and the conventional cold crystalloid cardioplegia (CCCP) in seven patients. All of them underwent isolated coronary artery bypass grafting. There was no marked difference between the CWBC and CCCP in post operative serum level of creatine kinase (MB type), cardiac output and dose of dopamine during they weaned from cardiopulmonary bypass. All patients treated with CWBC spontaneously restored the normal sinus rhythm shortly after removal of the aortic crossclamp, which was distinct from the fact that the CCCP group showed no such recovery. This result suggest that CWBC kept high-energy phosphate level without disturbing production of ATP in myocardium. Furthermore, reperfusion injury was also likely to be prevented by CWBC.

Aged↗

PubMed1993

Anomalous origin of the left coronary artery from the pulmonary artery. New operative technique.

We report a new operative technique for repair of anomalous origin of the left coronary artery from the pulmonary artery. The principles of the proposed technique are left main coronary angioplasty using a transected main pulmonary artery, side-to-side anastomosis of the aorta and newly created left coronary artery, and direct anastomosis of the transected pulmonary artery. No prosthetic material is used in this procedure. Our experience in two adults (a 35-year-old man and a 68-year-old woman) indicated that this technique permits two coronary system repair for any anatomic variation of the left coronary artery without the use of prosthetic material. This is more advantageous in infants.

Adult↗

PubMed1993

[Antitumor activity of a new antiestrogenic drug, toremifene (NK622) against human breast cancer xenografts in nude mice].

NK622, a novel tamoxifen(TAM) analog with nonsteroidal structure is an antiestrogenic drug with less toxicity compared with that of TAM. We studied the in vivo antitumor activity against human breast cancer xenografts in nude mice. NK 622 significantly inhibited the growth of estrogen-dependent Br-10 breast cancer but not inhibited the growth of estrogen-independent MC-2-JCK and MC-5-JCK when orally administered once daily for 14 days at the maximum tolerated dose (200mg/kg/day). The dose of NK622 in animal studies was calculated by measuring plasma level in patients receiving 40 mg/body/day oral treatment and clinically equivalent dose (CED) was determined. At the calculated CED, NK622 significantly inhibited the growth of Br-10. These results indicate that NK622 is a promising drug comparable to TAM because of the growth inhibition of estrogen-dependent breast cancers.

Animals↗

PubMed1993

[Coronary artery bypass surgery in patients with poor left ventricular function].

As the indications for coronary artery bypass grafting (CABG) among patients with poor left ventricular function remain incompletely defined, We undertook the study to assess the results of CABG surgery for a group of such patients. We retrospectively reviewed the clinical features and outcome for 7 patients with poor left ventricular function defined as an ejection fraction below 0.3 who underwent CABG. The mean age of the patients was 63 years (range, 38 to 78 years), and 4 were 70 years of age or older. All patients had history of previous myocardial infarction, and all had left main trunk stenosis or left main equivalent stenosis. The patients underwent CABG with three to six distal anastomoses (mean, 4.3/patient), the internal thoracic artery could be used in all patients, for one or two distal anastomoses (mean, 1.6/patient). Combined coronary endarterectomy was performed in 2 patients. With the exception of one 78-year-old patient with renal failure who died during the early postoperative period, all patients showed marked postoperative improvement in cardiac function. Cardiac catheterization and exercise stress test studies revealed significant improvement in left ventricular function and exercise tolerance in these six patients. These results suggest that excellent results can be obtained with CABG surgery in patients with poor left ventricular function when the viability of the myocardium in the bypassed area has been confirmed.

Adult↗

PubMed1993

[Coronary artery bypass grafting surgery without cardiopulmonary bypass].

Improved technique in coronary artery surgery has allowed coronary artery bypass graftings (CABG) to be placed on beating heart. The effects of extracorporeal circulation and cardiac arrest are eliminated. From Jan. 1991 to June, 1992, we performed CABG surgery without cardiopulmonary bypass and cardiac arrest in 15 patients; the age ranged from 47 to 82 years with the mean of 65. Patients who had LAD and/or RCA stenosis were candidate of this procedure in early series. However in recent series, we extended the candidate to three-vessel or LMT stenosis cases who were considered ineligible for standard CABG because of renal failure or poor left ventricular function. Distal anastomoses were performed with interruption of coronary flow. From one to two distal anastomosis to the LAD and/or RCA (mean 1.4/patient) were performed. The ITA was used in all 15 patients. Combined cardiac or vascular operation was performed in 5 patients (AAA repair, TAA repair, carotid endarterectomy or coronary endarterectomy). There were no deaths and no perioperative myocardial infarction. Postoperative angiography were performed in 12 patients with a patency rate of 89%.

Aged↗

PubMed1992

Molecular basis for the interaction of histamine with the histamine H2 receptor.

We undertook these studies to characterize the molecular basis of the interaction of histamine with the H2 receptor. Key areas of homology in the structures of the histamine H2 and beta 2 adrenergic receptor suggested specific transmembrane amino acids that might be important for binding of histamine. A third transmembrane aspartic acid of the histamine receptor (Asp98), thought to serve as a counter anion that interacts with the cationic amine moiety of histamine, was mutated to Asn98, and the mutated receptor was expressed in Hepa cells. Removal of the negatively charged amino acid abolished both binding of the H2 receptor antagonist [methyl-3H]tiotidine and histamine stimulated increases in cellular cAMP content. Mutation of a fifth transmembrane aspartic acid (Asp186) to Ala186 or Asn186 by itself or in conjunction with mutation of another fifth transmembrane amino acid (Thr190 to Ala190) resulted in a loss of [methyl-3H] tiotidine binding, although the generation of cAMP in response to histamine was maintained. The histamine receptor with only a Thr190 to Ala190 or Cys190 mutation retained the ability to bind [methyl-3H]tiotidine, but both the affinity and efficacy of binding were reduced. These data lead us to propose a model for histamine binding in which Asp98 is essential for histamine binding and action, Asp186 defines H2 selectivity, and Thr190 is important in establishing the kinetics of histamine binding, but is not essential for H2 selectivity.

Amino Acid Sequence↗

PubMed1992

Actin-binding proteins in the growth cone particles (GCP) from fetal rat brain: a 44 kDa actin-binding protein is enriched in the fetal GCP fraction.

Neuronal growth cones, the motile tips of growing neurites, are thought to play a significant role in nerve growth. To study the role of actin in their motility, we examined actin-binding proteins in growth cone particles (GCP) isolated from fetal rat brain, using a blot-overlay method with biotinylated actin. Among the more than ten species of actin-binding proteins in the GCP, a 44 kDa protein was found specifically in growth cones and was enriched in the cytoskeletal and the membrane skeletal subfractions from the GCP. This protein binds to actin in a Ca(2+)- and Mg(2+)-dependent manner, and ATP enhances its binding to actin. The protein was predominantly present in the fetal GCP, but it is expressed at a much lower level in the neonatal GCP and not detected in adult synaptosomes. The protein also bound to a deoxyribonuclease I column and was eluted by EGTA-containing buffer. The 44 kDa protein appears to be a novel actin-binding protein, since none of the known actin-binding proteins exhibit this combination of properties. Our results suggest that the protein may be involved with the early stages of neurite extension.

Animals↗

PubMed1992

[Magnetic resonance (MR) imaging of chordoma and chondroma in the skull base--differential diagnosis by IR sequence].

Differential diagnosis of chordoma and chondroma in the skull base is sometimes difficult. We retrospectively reviewed the MR images of 14 patients with skull base tumors (nine chordomas, four chondromas and one chondrosarcoma). MR imaging was performed with a 0.5 Tesla system (Picker International). Inversion recovery (IR) (2500-2100/600-500/40), T1-weighted spin echo (SE) (800-600/40), and T2-weighted SE (2500-1800/120) images were obtained. On IR images, seven of eight chordomas showed heterogeneous low signal intensity, and one chordoma and all chondromas showed markedly low signal intensity similar to that of CSF. Calcified or ossified portions of the chondromas were demonstrated as areas of moderately low intensity on IR images. Chondrosarcoma showed moderately low intensity similar to that of chordoma. T1-weighted SE images of chordoma and chondroma showed no difference in signal intensity. On T2-weighed SE images, six of nine chordomas and all chondromas showed markedly high signal intensity. Three chordomas and one chondrosarcoma showed moderately high signal intensity. In the diagnosis of skull base tumors, the IR sequence seems to be useful for differentiating chondroma from chordoma.

Adolescent↗

PubMed1992

Synthesis and antitumor activity of tropolone derivatives. 7. Bistropolones containing connecting methylene chains.

Bistropolone derivatives (4-12) containing differing lengths of linkage between the two tropolone rings were prepared and examined for their antitumor activity in in vitro (KB cell) and in vivo (leukemia P388 in mice) systems. Parent compound 3, related compounds previously prepared, and the new compounds 4-12 were evaluated for inhibitory activity against ribonucleotide reductase by indirect means to measure their effects on the dNTP pool imbalance. Present structure-activity relationship results would suggest that potently active bistropolones in vivo inhibit intracellular ribonucleotide reductase through chelating with the two irons at the two active sites of the enzyme.

Animals↗

PubMed1992

Characterization of acquired resistance to cis-diamminedichloroplatinum(II) in mouse leukemia cell lines.

We have established in vivo cisplatin-resistant mouse leukemia cell lines, L-1210/DDP and P388/DDP, in order to elucidate the mechanism of acquired resistance to cisplatin. Resistance indices were 22 and 14, respectively, when the cells were exposed to cisplatin for 48 h. Uptake of cisplatin by both resistant lines was significantly reduced, compared with values for the respective parent lines (17% for L-1210/DDP and 27% for P388/DDP, at 100 microM for 1 h). While glutathione contents in the resistant cells were 1.7-1.9 times higher than those in the sensitive ones, their reduction by preincubation with buthionine sulfoximine did not influence the sensitivity of the cells to cisplatin. In addition, the resistant lines did not show lower sensitivity to CdCl2 than the respective sensitive ones, suggesting that intracellular SH groups might contribute little to the mechanism of cisplatin resistance in these cells. Postincubation with DNA repair inhibitors, caffeine and aphidicolon, did not selectively enhance the sensitivity of the resistant cells to cisplatin. These results suggested that reduced drug uptake would be a primary mechanism of cisplatin resistance in L-1210/DDP and P388/DDP. Cross-resistance patterns to platinum complexes were quite different between L-1210/DDP and P388/DDP. Colon 26/DDP, another cisplatin-resistant mouse tumor showed a different pattern from those observed with L-1210/DDP and P388/DDP. In the development of new platinum complexes we should use plural resistant lines for examining cross-resistance patterns to candidate platinum complexes.

Animals↗

PubMed1992

Antitumor activity and cellular accumulation of a new platinum complex, (-)-(R)-2-aminomethylpyrrolidine(1,1-cyclobutanedicarboxylato)platinum( II) monohydrate, in cisplatin-sensitive and -resistant murine P388 leukemia cells.

We have examined the cytotoxicity and accumulation of (-)-(R)-2-aminomethylpyrrolidine(1,1-cyclobutanedicarboxylato++ +)platinum(II) monohydrate (DWA2114R) in parent and cisplatin-resistant mouse P388 leukemia cells (P388 and P388/DDP), in comparison with those of cisplatin (CDDP) and carboplatin (CBDCA). The degrees of resistance to CDDP and CBDCA, expressed as the ratio of IC50 for P388/DDP cells to IC50 for P388 cells, were 75-33 and 100-27, respectively, under the conditions of 2-24 h exposure to each drug at a density of 10(6) cells/ml. The corresponding values (25-7) for DWA2114R were relatively low. Accumulations of CDDP and CBDCA were reduced in P388/DDP cells; however, no reduction in accumulation of DWA2114R was observed at various exposure periods and concentrations of the drugs. The accumulations of CDDP in P388 and P388/DDP cells at drug concentrations corresponding to the IC50 values for drug exposure periods of 2-24 h were 0.41-0.97 and 13.1-33.7 ng Pt/10(7) cells, respectively, suggesting that an intracellular mechanism of resistance against CDDP could be activated in P388/DDP cells. P388/DDP cells also showed relatively low resistance to DWA2114R via this mechanism in comparison with CDDP and CBDCA. From the relationship between structure and activity of several Pt-complexes, these different properties of DWA2114R compared with CDDP and CBDCA could be due not only to the differences in carrier ligand structure but also to the properties of the whole molecule associated with the carrier ligand and leaving group.

Animals↗

PubMed1992

Muscle nerve sympathetic activity during sleep and its change with arousal response.

Muscle nerve sympathetic activity (MSA) was recorded from the peroneal nerve during wakefulness and in different sleep states in healthy young adults. The burst rate (BR) of MSA significantly decreased in NREM, but not in REM sleep, compared with that during wakefulness. Transient increases of MSA frequently appeared in association with rapid eye movements during REM sleep. K-complexes in Stage 2 were almost always accompanied by a burst of MSA, and were followed by a transient elevation of arterial blood pressure. Auditory stimuli applied in sleep induced a burst of MSA followed by a transient increase of arterial blood pressure, only when they elicited an arousal response in the EEG, such as a K-complex, transient EEG desynchronization, or a short train of alpha waves. The same stimuli applied during wakefulness did not induce such changes in MSA and in arterial blood pressure.

Journal Article↗

PubMed1992

[A case of tracho-bronchial aspergillosis complicated with acute myeloblastic leukemia].

A 59-year-old male was admitted to our hospital in Jan. 1991 with complaints of general malaise and palpitation. Laboratory findings on admission showed anemia, thrombocytopenia and leukopenia consisted of 2.0% myeloblasts with Auerbodies. The bone marrow study showed granuloid hyperplasia with 45.5% myeloblasts. The diagnosis of acute myeloblastic leukemia (M1) was made. After BHAC-AMP therapy, he obtained complete remission. However, he complained of fever and cough, and his chest X ray film showed a focal infiltrative shadow in the right upper lung field. Antibiotics for bacteria and fungus were administered and the abnormal shadow improved in a week. However, as he had hemosputum, the bronchoscopic examination was performed, and multiple ulcers covered by yellow-white tissue were revealed on the wall of the trachea and bilateral main bronchi. Biopsy specimens obtained by transbronchial biopsy showed bronchial aspergillosis. Though intravenous infusion and inhalation of amphotericin B were effective for aspergillosis, he had a relapse of the leukemia and died in autumn, 1991.

Aspergillosis↗

PubMed1992

[Cytomegalovirus pneumonia treated with ganciclovir and intravenous CMV-hyperimmune globulin: case report].

A 60-year-old male with adult T-cell leukemia (ATL) complained of fever, cough and dyspnea, after anti-leukemic chemotherapy. Chest X-ray film showed a diffuse interstitial shadow, and cytomegalic inclusions and cytomegalovirus (CMV) antigen were detected in the bronchoalveolar lavage specimen and sputum. The diagnosis of CMV pneumonia was made, then ganciclovir and intravenous CMV-hyperimmune globin was administered. Although CMV pneumonia was improved with the treatment, the patient died of ATL. There was no cytomegalic inclusions in the lung but in the adrenal at autopsy. The combination therapy of ganciclovir and intravenous CMV-hyperimmune globulin is considered to be effective for CMV pneumonia.

Cytomegalovirus↗

PubMed1992

[A case of penicillin-resistant pneumococcal pneumonia and penicillin-binding proteins of the clinical isolates].

We experienced a case of a 68-year-old female with beta-lactam antibiotics including penicillin G (PCG) resistant pneumococcal pneumonia, leading to death during the treatment with ceftizoxime (CZX). We reported the clinical course and the mechanism of resistance of isolated bacteria. The present case is the first in Japan. Minimum inhibitory concentration (MIC) against Streptococcus pneumoniae 88031 isolated from the present case was 1.56 micrograms/ml in PCG and 6.25 micrograms/ml in CZX, showing PCG resistance. The isolate was no beta-lactamase production and serotype 23. The drug susceptibility in 34 strains of S. pneumoniae which were isolated as causative organism of respiratory infection in our department in 1988 was studied. PCG high resistant strain (PCG MIC greater than 1.56 micrograms/ml) was only observed in the isolated strain in the present case and PCG low sensitive strains (PCG MIC = 0.1-1.0 micrograms/ml) were observed in 3 strains (8.8%). The CZX resistance was observed only in the present case. The detection of penicillin-binding protein (PBP) and binding affinity of beta-lactam antibiotics were studied using PCG sensitive strain, S. pneumoniae type I (preserved strain PCG MIC = 0.05 micrograms/ml, CZX MIC = 0.1 micrograms/ml, CMX MIC = 0.025 micrograms/ml) and PCG resistant strain, S. pneumoniae 88031. The result obtained showed that PBP1a, detected in sensitive strain type I, was not detected in resistant strain 88031 and PBP1b was increased. The binding of 14C-PCG of PCG resistant strain to PBP1b showed lower affinity for CZX and CMX than PCG sensitive strain.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1992

Intramedullary spinal cord tumors: significance of associated hemorrhage at MR imaging.

Magnetic resonance (MR) images obtained in 35 patients with intramedullary spinal tumors were reviewed. Hypointense areas on both T1- and T2-weighted images were seen within or around eight tumors, all of which were in the cervical cord. Hypointensity at the tumor margin was seen in seven cases. Hypointensity within the tumor was seen in two cases. (One case had both types of hypointensity). In seven surgically confirmed cases, hypointensity at the tumor margin was found to be a relatively firm pseudocapsule, and hypointensity within the tumor corresponded to intratumoral hematoma. All of the tumors with hypointensity were ependymomas at histologic examination. When MR imaging shows an intramedullary tumor with hypointensity at the tumor margin, it is suggestive, but not pathognomonic, of an ependymoma.

Adult↗

PubMed1992

Synthesis and antitumor activity of fused quinoline derivatives. III. Novel N-glycosylamino-indolo[3,2-b]quinolines.

Novel indolo[3,2-b]quinolines (1b-k), having a nitro, amino, acetamido, methanesulfonamido, or glycosylamino group at the 2, 7, or 8-position, were prepared and their antitumor activities against P388 leukemia in mice were examined. The 7-galactopyranosylamino derivative (1g) showed the most potent activity (optimal dose = 25 mg/kg, T/C greater than 333%, cure rate 5/6).

Animals↗