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S Taniguchi

Publications and source records attributed to S Taniguchi.

At least 145 records · Page 8Linked to original sources
PubMed2000

Aortic stent-grafting with transrenal fixation: use of newly designed spiral Z-stent endograft.

PURPOSE: To evaluate the feasibility and efficacy of a newly designed stent-graft placed across the renal arteries for exclusion of abdominal aortic aneurysms (AAAs) with short or tortuous proximal necks. METHODS: Among a group of AAA patients treated with endovascular grafting, 5 had tortuous proximal necks and 13 had necks <20 mm (mean 13 mm). In these 18 cases, a 2- to 3-cm uncovered segment of the stent-graft was placed transrenally using a catheter inserted into the renal artery as a guide for graft margin positioning. A newly designed stent-graft was constructed from a custom-made spiral Z-stent covered with a thin-walled Dacron material; the endografts were deployed through 16-F (aortoaortic model) or 18-F sheaths (bifurcated devices). Renal function was assessed by preoperative and postoperative measurement of urea nitrogen and creatinine. Aneurysm exclusion and renal artery patency were evaluated during follow-up using spiral computed tomography and angiography. RESULTS: The stent-grafts were correctly placed at the intended site in all 18 patients. Renal function was not affected except transiently in 1 patient who developed bilateral renal artery stenoses 24 hours after the procedure; Palmaz stents were deployed in each renal artery to reestablish satisfactory blood flow. Of the 33 renal arteries crossed by the bare stent-graft segment, all were patent over a mean 14-month follow-up (range 7-24), including the patient with Palmaz stents implanted for postprocedural renal stenosis. Complete aneurysm exclusion was maintained in 15 (83%) of 18 patients; proximal leaks persisted in 3 patients, including 2 with severely angled proximal necks. CONCLUSIONS: Transrenal placement of the uncovered leading edge of custom-made spiral Z-stent-based endografts appears feasible and clinically effective in the treatment of AAAs with short or tortuous proximal necks.

Aged↗
PubMed2000

Inhibition of glucose-induced insulin secretion by 4-hydroxy-2-nonenal and other lipid peroxidation products.

Lipid peroxidation due to oxidative stress is accelerated under hyperglycemic conditions such as diabetes mellitus. The effect of 4-hydroxy-2-nonenal (HNE) and other lipid peroxidation products on the ability of isolated rat pancreatic islets to secrete insulin was examined in this study. HNE concentration- and time-dependently deteriorated glucose-induced insulin secretion: insulin secretion was decreased by 50% when measured after incubation of islets with 100 microM HNE for 1 h. Other lipid peroxidation products, e.g. 2-hexenal and 2-butenal, also inhibited glucose-induced insulin secretion. HNE at 100 microM lowered alpha-ketoisocaproate-induced insulin secretion, whereas leucine-induced insulin secretion was stimulated. Insulin secretion induced by 10 mM glyceraldehyde was slightly decreased by HNE. On the other hand, HNE severely decreased insulin secretion induced by 10 mM glyceraldehyde and 2.8 mM glucose. Glucose utilization and glucose oxidation were significantly lowered in islets treated with HNE. The amounts of fructose 1,6-bisphosphate and dihydroxyacetone phosphate in islets were decreased by treatment with HNE, whereas the amount of fructose 6-phosphate was increased. Our study indicates that HNE and other lipid peroxidation products impair insulin secretion induced by glucose probably through affecting both the glycolytic pathway and the citric acid cycle.

Aldehydes↗
PubMed2000

Pulmonary ventricular outflow reconstruction with a size-reduced cryopreserved pulmonary valve allograft: mid-term follow-up.

Surgical reduction of pulmonary allografts is being performed because of the shortage of allografts of suitable size for pediatric use. However, the outcome of size-reduced pulmonary allografts for pulmonary conduits is unknown. In the present study, cryopreserved pulmonary allografts harvested from adults at the time of kidney donation were size-reduced and used in 4 children, 2 with pulmonary atresia and ventricular septal defect and 2 with atrioventricular discordance, pulmonary atresia and ventricular septal defect. They all had undergone right and/or left modified Blalock-Taussig shunt operations with a 5-mm synthetic graft prior to the reparative operations. They underwent definitive repair with a size-reduced cryopreserved pulmonary allograft valved conduit and were followed up for 2-5 years. Postoperative echocardiographic and cineangiographic assessments revealed excellent function of the pulmonary bicuspidalized valves with a minimal pressure gradient and no, or only trivial, regurgitation. Although the long-term result of a cryopreserved bicuspid pulmonary valved conduit remains unknown, the remodeled bicuspid pulmonary allograft conduits showed excellent hemodynamic characteristics in mid-term follow-up and appear to be a reasonable alternative to other types of conduits when an appropriate-sized allograft is not available.

Adult↗
PubMed2000

Retrospective study of porcine circovirus 2 infection in Japan: seven cases in 1989.

Retrospectively, we demonstrated that seven pigs necropsied in 1989 had characteristic porcine circovirus 2 (PCV-2) lymphoid tissue lesions of severe lymphoid depletion, syncytial giant cell formation, and intracytoplasmic inclusion bodies in macrophages. Immunohistochemically, PCV-2 antigen was detected in these tissues and the distribution of positive staining corresponded to the distribution of inclusion bodies. Electron microscopy demonstrated viral particles compatible with porcine PCV-2. Therefore, the disease occurred in Japan as early as 1989.

Animals↗
PubMed2000

Sequential chemoimmunotherapy with cisplatin, interferon-beta and interleukin-2 inhibits the growth of B16-F1 melanoma in syngeneic mice.

Sequential combinations of chemotherapy with biological response modifiers has recently been evaluated as systemic treatment for patients with advanced melanoma. The response rates of the chemoimmunotherapy were reported to be higher than conventional treatment using chemotherapy or biological agents alone. To investigate the effectiveness of such chemoimmunotherapy, we evaluated the antitumour effect of sequential chemoimmunotherapy in vivo using a B16 mouse melanoma system. In this sequential regimen, administration of cisplatin (CDDP) was followed by interferon-beta (IFNbeta) and interleukin-2 (IL-2). This combination therapy synergistically inhibited the growth of B16-F1 melanoma and prolonged the survival of mice bearing B16-F1. In contrast, this therapy did not show any antitumour effect on B16-F10 melanoma. The exact mechanism of the antitumour effect is not clear, but the following results were noted: no synergistic effect of this therapy was detected in nude mice, neutralizing anti-IFNgamma antibody significantly blocked the antitumour effect of this therapy, and the number of apoptotic melanoma cells was significantly increased in melanoma tissues removed from mice treated with this therapy. These results demonstrated the potent immunological antitumour effect of this sequential chemoimmunotherapy.

Animals↗
PubMed2000

[A case of posttraumatic severe ventriculitis treated by intraventricular lavage].

A 44-year-old male was admitted in a state of semicoma, tonic convulsion and elevated body temperature nine days after sustaining head injury. He had severe nuchal rigidity. Computed tomography revealed dilation of ventricles and swelling of the brain parenchyma. We performed cerebrospinal fluid (CSF) drainage of both lateral ventricles immediately. The fluid drained from both ventricles was just like pus. We diagnosed the patient's condition as posttraumatic ventriculitis and meningitis. We performed intraventricular lavage (IL) which was our ventricular irrigating technique. IL was repeated until the 7th day postoperatively. The CSF data improved immediately. Continuous spinal drainage (CSD) also was used for CSF drainage from the 7th day postoperatively. The patient recovered without the need for CSF shunt. Some authors have reported the usefulness of continuous intraventricular irrigation (CIVI) for treatment of severe ventriculitis. However, their patients required CSF shunt surgeries. Such shunts are likely to become infected more frequently than routine shunting. Our IL was able to drain pus and inflammatory products in the ventricles before the formation of septations in the ventricles. We emphasize that IL in combination with CSD is able to bring about good results for patients with severe ventriculitis.

Adult↗
PubMed2000

[Two cases of ischemic changes indicated in the amplitude of motor evoked potentials during thoracoabdominal aortic aneurysm repair].

Monitoring of motor-evoked potentials (MEPs) is employed to examine functional integrity of descending motor pathway during thoracic aortic surgery. We experienced two cases of intraoperative changes in MEPs during thoracic aortic replacement. In one case, MEPs recovered after the intercostal artery reattachment, and in another case after the release of aortic clamping. No postoperative paraplegia was found in both cases. We conclude that monitoring of MEPs is useful not only because we can detect symptoms of the spinal cord injury from ischemia immediately but also because they give us a clue to decide operative procedures.

Aged↗
PubMed1999

Roxithromycin and clarithromycin, 14-membered ring macrolides, potentiate the antitumor activity of cytotoxic agents against mouse B16 melanoma cells.

We previously reported antiangiogenic activity of roxithromycin and clarithromycin, 14-membered ring macrolide antibiotics. In the present study, we examined the antitumor effects of roxithromycin and clarithromycin, alone and in combination with several cytotoxic drugs, on mouse B16BL6 melanoma cells in vivo and in vitro. Both roxithromycin and clarithromycin potentiated the inhibition of tumor growth induced by cyclophosphamide, cis-diamminedichloroplatinum(II), Adriamycin and vindesine in vivo. However, neither roxithromycin nor clarithromycin, altered the cytotoxicity of 4-hydroperoxycyclophosphamide, cis-diamminedichloroplatinum(II), Adriamycin or vindesine in an in vitro cell proliferation assay. These results suggest that the antiangiogenic activity of roxithromycin and clarithromycin may provide beneficial effects in combination with cytotoxic therapies against solid tumors.

Animals↗
PubMed1999

ASC, a novel 22-kDa protein, aggregates during apoptosis of human promyelocytic leukemia HL-60 cells.

The cytoskeletal and/or nuclear matrix molecules responsible for morphological changes associated with apoptosis were identified using monoclonal antibodies (mAbs). We developed mAbs against Triton X-100-insoluble components of HL-60 cells pretreated with all-trans retinoic acid. In particular, one mAb recognized a 22-kDa protein that exhibited intriguing behavior by forming an aggregate and appearing as a speck during apoptosis induced by retinoic acid and other anti-tumor drugs. Cloning and sequencing of its cDNA revealed that this protein comprises 195 amino acids and that its C-terminal half has a caspase recruitment domain (CARD) motif, characteristic of numerous proteins involved in apoptotic signaling. We referred to this protein as ASC (apoptosis-associated speck-like protein containing a CARD). The ASC gene was mapped on chromosome 16p11.2-12. The antisense oligonucleotides of ASC were found to reduce the expression of ASC, and consequently, etoposide-mediated apoptosis of HL-60 cells was suppressed. Our results indicate that ASC is a novel member of the CARD-containing adaptor protein family.

Amino Acid Sequence↗
PubMed1999

Decreases in Ikaros activity correlate with blast crisis in patients with chronic myelogenous leukemia.

Gene targeting studies in mice have shown that the lack of Ikaros activity leads to T-cell hyperproliferation and T-cell neoplasia, establishing the Ikaros gene as a tumor suppressor gene in mice. This prompted us to investigate whether mutations in Ikaros play a role in human hematological malignancies. Reverse transcription-PCR was used to determine the relative expression levels of Ikaros isoforms in a panel of human leukemia/lymphoma cell lines and human bone marrow samples from patients with hematological malignancies. Among the cell lines examined, only BV-173, which was derived from a chronic myelogenous leukemia (CML) patient in lymphoid blast crisis, overexpressed the dominant-negative isoform, Ik-6. In 9 of 17 samples of patients in blast crisis of CML, Ikaros activity had been reduced either by drastically reducing mRNA expression (4 of 17) or by overexpressing the dominant-negative isoform Ik-6 (5 of 17). Significantly, expression of Ikaros isoforms seemed normal in chronic phase CML patients and patients with other hematological malignancies. In some cases, overexpression of the dominant-negative Ik-6 protein was confirmed by Western blot analysis, and Southern blot analysis indicated that decreases in Ikaros activity correlated with a mutation in the Ikaros locus. In summary, these findings suggest that a reduction of Ikaros activity may be an important step in the development of blast crisis in CML and provide further evidence that mutations that alter Ikaros expression may contribute to human hematological malignancies.

Adult↗
PubMed1999

The induction of smooth muscle alpha actin in a transformed rat cell line suppresses malignant properties in vitro and in vivo.

A normal rat fibroblast 3Y1 cell line expresses smooth muscle a actin and the expression of alpha actin is suppressed in the transformant (SR-3Y1-2) induced by a Raus sarcoma virus. Gene transfer with smooth muscle alpha actin into the SR-3Y1-2 cell line reduced growth and invasiveness in vitro, as well as tumor growth and experimental lung metastasis depending on the expression of the alpha actin. These results indicated that smooth muscle alpha actin is involved in the regulation of cell growth as well as cell motility and thus leads to the suppression of malignant phenotypes in transformed cells.

Actins↗
PubMed1999

Acarbose-induced generalised erythema multiforme.

A 58-year-old man with diabetes mellitus was treated with acarbose 300 mg daily. 13 days after the start of treatment with acarbose, generalised erythema multiforme developed with blood eosinophilia. Tissue eosinophilia was also found histologically. A challenge test for acarbose confirmed allergic reaction clinically and histologically.

Acarbose↗
PubMed1999

A TSH/dibutyryl cAMP activated Cl-/I- channel in FRTL-5 cells.

An iodide (I) and chloride (Cl) channel has been identified in the continuously cultured FRTL-5 thyroid cell line using a cell attached patch clamp technique. The channel is activated by TSH and dibutyryladenosine cyclic monophosphate (Bt2-cAMP) but not by phorbol 12-myristate 13-acetate (TPA). Gluconate can not replace chloride or iodide and the channel is impermeable to Na+,K+ and tetraethylammonium ions. The current-voltage relationship demonstrates that the single channel current is a linear function of the clamp voltage. Single channel currents reversed at a pipette potential close to 0 mV. The mean single channel conductance was 60 pS for Cl- and 50 pS for I-. From the I-V relationship there was a strong outward rectification with Cl-, and a complete block with I-, in the single channel current above +40 mV. The feature of the channel is manifested in the single channel records by four distinct, equally spaced conductance levels. We suggest the channel is important for the transport of I and Cl ions across the apical membrane into the colloid space and is important for hormone synthesis and follicle formation.

Animals↗
PubMed1999

Possible role of calponin h1 as a tumor suppressor in human uterine leiomyosarcoma.

BACKGROUND: Calponin h1, a basic actin-binding protein capable of inhibiting smooth muscle contraction, is a constitutive element of smooth muscle cells. However, in leiomyosarcoma (a type of smooth muscle neoplasm of the uterus), reduced expression of calponin h1 is observed, as we have reported previously. In this study, we sought to assess the effects (in vitro and in vivo) of increasing calponin h1 expression in leiomyosarcoma cells. METHODS: A plasmid containing a human calponin h1 complementary DNA and a bacterial neomycin-resistance gene was transfected into the human leiomyosarcoma cell lines SKN and SK-LMS-1 by electroporation. Southern blotting, reverse transcription-polymerase chain reaction analysis, western blotting, and immunohistochemistry were used to confirm DNA transfer and expression of the calponin h1 protein in neomycin-resistant clones. We characterized the morphology of calponin h1-transfected cells, and we evaluated their proliferative activity and tumorigenicity by use of a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay, an anchorage-independent growth assay, and a nude mouse tumorigenicity assay. RESULTS: The morphology of calponin h1-transfected cells in culture resembled that of cultured normal myometrial smooth muscle cells. With SK-LMS-1 cells, proliferation of calponin h1-transfection cells was reduced to 69% of control; with SKN cells, calponin h1 transfection reduced proliferation to 70% of control. In assays of anchorage-independent growth and in vivo tumorigenicity, both growth and tumorigenicity were statistically significantly reduced in calponin h1-transfected leiomyosarcoma cells. CONCLUSIONS: Calponin h1 may function as a tumor suppressor in leiomyosarcoma. Clinically, transfer of a calponin h1 complementary DNA into poorly differentiated leiomyosarcoma cells may be of potential therapeutic value through induction of a normal, differentiated cellular phenotype.

Animals↗
PubMed1999

Simple and rapid analytical method for carbapenems using capillary zone electrophoresis.

A simple and rapid analytical method for carbapenems using high-performance capillary electrophoresis is described. All therapeutic carbapenem injections in Japan (imipenem, panipenem and meropenem) and four other beta-lactams (piperacillin, cefotiam, cefotaxime, latamoxef) were separated and determined with good repeatability in about 10 min using simple free zone capillary electrophoresis. The electrophoresis buffer was 100 mM phosphate buffer of pH 8.0, and a fused-silica capillary of 25 microm I.D. and 47 cm length was adopted. The present method was successfully applied to monitor the degradation of carbapenems under various conditions (at various temperatures or in coexistence with other drugs prescribed in the case of methicillin-resistant Staphylococcus aureus).

Anti-Bacterial Agents↗
PubMed1999

Motor-evoked potentials elicited from human erector spinae muscles by transcranial magnetic stimulation.

STUDY DESIGN: The compound muscle action potentials elicited from the erector spinae muscles by transcranial magnetic stimulation was studied in 15 healthy adults. OBJECTIVE: To describe the recording procedure for consistent compound muscle action potentials elicited from the human erector spinae by transcranial magnetic stimulation and to establish the normal latency ranges of the responses, at respective spinal levels, for the practical use of this test. SUMMARY OF BACKGROUND DATA: Although recording of the compound muscle action potentials from limb muscles after transcranial magnetic stimulation has been extensively studied, the use of the erector spinae as the target muscle has not, probably because of the difficulty of consistently evoking compound muscle action potentials. METHODS: Compound muscle action potentials from the erector spinae muscles were recorded with the subject prone during tonic voluntary background contraction of the back extensor muscles at approximately 20% of maximum effort. The compound muscle action potentials were recorded concurrently at multiple levels after magnetic stimulation to the brain with a round coil centered over the vertex. RESULTS: The onset and peak latencies (mean +/- SD) of the major negative potential increased progressively toward the caudal level from 13.4 +/- 2.2 msec and 17.6 +/- 2.2 msec at T5-T6 to 20.8 +/- 1.5 msec and 26.3 +/- 3.0 msec at L4-L5 in healthy subjects. The latencies changed significantly between two adjacent segments from T5-T6/T6-T7 through T12-L1/L1-L2. CONCLUSIONS: The compound muscle action potential was elicited from the voluntarily contracted erector spinae at all spinal levels from T5-T6 through L4-L5 in all subjects tested. This noninvasive test has potential for evaluating the functional integrity of the motor pathway in the thoracic spinal cord, the spinal nerves, or both.

Adult↗
PubMed1999

Quantitative determination of E5880 in rat plasma by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry.

A simple and sensitive method is described for the determination of E5880 in rat plasma. The method is based on high-performance liquid chromatography/electrospray ionization mass spectrometry, using deuterated E5880 as an internal standard. Selected reaction monitoring is employed for selectivity and sensitivity, this in turn enables quantification in a short period of time (within 7 minutes) over the extended range of 0.1-1000 ng/ml with acceptable precision and accuracy. The method demonstrated to be suitable for the quantitative analysis of E5880 in rat plasma. The pharmacokinetic profile of E5880 after a single intravenous administration of E5880 was elucidated.

Animals↗