PubMed Health⌕ Search

Biomedical subjects

T Yoshie

Publications and source records attributed to T Yoshie.

At least 19 recordsLinked to original sources
PubMed2004

Vacuum Rabi splitting with a single quantum dot in a photonic crystal nanocavity.

Cavity quantum electrodynamics (QED) systems allow the study of a variety of fundamental quantum-optics phenomena, such as entanglement, quantum decoherence and the quantum-classical boundary. Such systems also provide test beds for quantum information science. Nearly all strongly coupled cavity QED experiments have used a single atom in a high-quality-factor (high-Q) cavity. Here we report the experimental realization of a strongly coupled system in the solid state: a single quantum dot embedded in the spacer of a nanocavity, showing vacuum-field Rabi splitting exceeding the decoherence linewidths of both the nanocavity and the quantum dot. This requires a small-volume cavity and an atomic-like two-level system. The photonic crystal slab nanocavity--which traps photons when a defect is introduced inside the two-dimensional photonic bandgap by leaving out one or more holes--has both high Q and small modal volume V, as required for strong light-matter interactions. The quantum dot has two discrete energy levels with a transition dipole moment much larger than that of an atom, and it is fixed in the nanocavity during growth.

Journal Article↗
PubMed2000

Dynamical quark effects on light quark masses

Light quark masses are calculated in lattice QCD with two degenerate flavors of dynamical quarks. The calculations are made with improved actions with lattice spacing a = 0.22-0.11 fm. In the continuum limit we find m(M&Smacr;)(ud)(2 GeV) = 3.44(+0.14)(-0.22) MeV using the pi and rho meson masses as physical input, and m(M&Smacr;)(s)(2 GeV) = 88(+4)(-6) MeV or 90(+5)(-11) MeV with the K or straight phi meson mass as additional input. The quoted errors represent statistical and systematic combined, the latter including those from continuum and chiral extrapolations, and from renormalization factors. Compared to quenched results, two flavors of dynamical quarks reduce quark masses by about 25%.

Journal Article↗
PubMed2000

Quenched light hadron spectrum

We present results of a large-scale simulation for the flavor nonsinglet light hadron spectrum in quenched lattice QCD with the Wilson quark action. Hadron masses are calculated at four values of lattice spacing in the range a approximately 0.1-0.05 fm on lattices with a physical extent of 3 fm at five quark masses corresponding to m(pi)/m(rho) approximately 0.75-0.4. The calculated spectrum in the continuum limit shows a systematic deviation from experiment, though the magnitude of deviation is contained within 11%. Results for decay constants and light quark masses are also reported.

Journal Article↗
PubMed1993

Pharmacokinetics of temocapril and enalapril in patients with various degrees of renal insufficiency.

Temocapril is a novel ACE inhibitor that is cleared via dual excretion routes in humans. Borderline or mildly hypertensive patients with normal renal function [group 1, creatinine clearance (CLCR) > 70 ml/min (4.2 L/h), n = 12], moderate renal impairment [group 2, CLCR 30 to 70 ml/min (1.8 to 4.2 L/h), n = 12] or severe renal impairment [group 3, CLCR < 30 ml/min (1.8 L/h), n = 12] received a single oral dose of either temocapril 1 mg (n = 6, each group) or enalapril 5mg (n = 6, each group). These 2 drugs gave similar values for the area under the plasma concentration-time curve (AUC) of the active diacids. The maximum plasma concentration of enalapril diacid was increased 2- and 6-fold in moderate and severe renal impairment, respectively, whereas that of temocapril diacid was not altered. The AUC of enalapril diacid increased 13-fold at CLCR values < 30 ml/min, but that of temocapril diacid increased only 2-fold. The duration of plasma ACE inhibition due to enalapril was greatly prolonged by the impairment of renal function, whereas that due to temocapril was affected very little. Urinary recovery of temocapril diacid was decreased markedly in patients with severe renal dysfunction, most probably because the diacid was excreted through the biliary route. On the other hand, urinary recovery of enalapril diacid remained fairly high even in patients with severe renal impairment, because of extremely high plasma diacid concentrations resulting from the lack of biliary excretion. These observations suggest that temocapril is beneficial in the treatment of hypertension in patients with severely impaired renal function.

Adult↗
PubMed1993

[The effects of rhodamine 123 on the cell growth of the cultured cells derived from urogenital carcinoma].

Rhodamine 123 (Rh123) is a red fluorescence dye, which is accumulated more and retained longer in the mitochondria of malignant transformed cells. In this study, the suppressive effects on the growth of cultured urogenital carcinoma cells (PC-3 and LNCaP from prostate carcinoma, T-24 from bladder cancer, and SV-HUC-1 human ureteral transitional cell transformed by SV virus in vitro, ACHN, YCR-1 and RCF213 from renal cell carcinoma) were examined. The cell growth of PC-3, LNCaP, T-24 and SV-HUC-1 was suppressed significantly in a dose dependent manner, but that of cells derived from renal cell carcinoma was not suppressed. The uptake and elimination of Rh123 in PC-3, ACHN and YCR-1 were not significantly different. When administered with verapamil and buthionine sulfoximine, which are reported to be chemical modulators of anticancer agents, Rh123 suppressed the growth of ACHN and YCR-1 significantly. Rh123 seems to have an anticancer effect against the urogenital carcinomas, and the role of Rh123 with hyperthermia, photodynamic therapy and chemotherapy requires further investigation.

Antimetabolites, Antineoplastic↗
PubMed1992

Effects of pravastatin on serum lipids and apolipoproteins in hyperlipidemia of the nephrotic syndrome.

The nephrotic syndrome is often accompanied by hyperlipidemia associated with an increased risk of accelerated atherosclerosis. The present study was undertaken to evaluate the effects of pravastatin, a novel competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, on the serum lipids and apolipoproteins in patients with this syndrome and marked hyperlipidemia. Eleven adult patients received 10 mg of pravastatin twice daily for 4 to 8 weeks. The total serum cholesterol decreased from 426 +/- 44 to 309 +/- 18 mg/dl (-27.4%, mean +/- S.E.; p less than 0.01) following administration of pravastatin. The serum triglyceride decreased from 332 +/- 122 to 229 +/- 50 mg/dl (-30.9%), although this change was not significant. Despite the fact that the HDL cholesterol level was barely changed (51 +/- 7 to 51 +/- 6 mg/dl), the LDL cholesterol fell from 313 +/- 30 to 211 +/- 16 mg/dl (-32.5%; p less than 0.005), and the LDL to HDL cholesterol ratio fell from 7.57 +/- 1.59 to 4.94 +/- 0.88 (-34.8%; p less than 0.05). These changes caused the atherogenic index to decline from 9.6 +/- 2.4 to 6.1 +/- 1.2 (-36.5%; p less than 0.05). No significant alterations could be found among apolipoproteins A-1, A-2, B, C-2, C-3, and E. During the present study period, pravastatin was well tolerated and did not affect the serum protein, albumin, serum urea nitrogen, creatinine levels, or urine protein excretion. Also, there were no serious adverse effects. Pravastatin appears to be effective for treating patients with hyperlipidemia of the nephrotic syndrome.

Adult↗
PubMed1991

[Chemotherapy of prostatic cancer].

CDDP combined chemotherapy was performed in 55 cases out of 229 prostatic cancer patients who were treated in Nara Medical University and Nara Prefectural Nara Hospital between January 1979 and August 1989. The previously untreated 33 patients received chemotherapy with anti-androgen treatment as an initial treatment, as well as 7 cases of unresponsive to antiandrogen treatment, 14 relapsing cases and one case with recurrence after total prostatectomy. The major regimens of chemotherapy were cis-diammine dichloroplatinum (CDDP) alone in 16 cases, PVB regimen (bleomycin or peplomycin + vincristine + CDDP) in 19 cases, and CAP regimen (cyclophosphamide + adriamycin + CDDP) in 16 cases. Complete response was not achieved or partial response was observed in 20 cases (34%), no change was seen in 20 cases (34%), and progression was seen in 19 cases (32%). Among each evaluable lesion, effects (CR + PR) were observed in 40% in the prostate, in 18% in the bone lesions, in 44% in the soft tissue lesions, and in 42% in the prostatic tumor marker. The 7-year survival rate of the chemotherapy group (35.6%) was better than that of the antiandrogen treatment group (26.6%) in stage D patients, but was not significant statistically When evaluated by the regimen, a partial response was observed in 56% of CDDP alone, in 21% of PVB regimen, and in 38% of the CAP regimen. However, there was no significant difference in survival rate among the regimens. As an adverse effect, myelosuppression and renal toxicity seemed to be dose limiting factors of CDDP combined chemotherapy for advanced prostatic cancer patients.

Aged↗
PubMed1991

[Study on the swine glomerulopathy resembling human IgA nephropathy].

Naturally occurring swine glomerulopathy was investigated and its glomerular tissue injury was compared with that of human IgA nephropathy. Mild proteinuria (30%) and microhematuria (17%) was found in 30 six-month-old swine. Serum creatinine level was 1.8 +/- 0.4 (mean +/- SD) mg/dl. Light microscopy (LM) disclosed diffuse or focal glomerulopathy with mesangial enlargement and hemispherical deposits in six-month-old swine. Electron microscopy revealed dense deposits in the mesangial, para-mesangial and sub-endothelium areas. On immunofluorescence+ (IF) staining findings, granular deposits of IgA (97%), IgG (97%), IgM (80%), C3 (100%), and mycoplasma hyorhinis (MH) antigen (90%) were found in the mesangial areas and along the capillary walls. One three-month-old pig and one five-year-old Goettingen mini pig were also found to have granular deposits of immunoglobulin and MH antigen in the glomerulus. In contrast, no glomerular lesion was found in all 4 new-born pigs and 4 fetal pigs by LM and IF study. In six-month-old swine anti-nuclear factor and anti-DNA antibody were negative, and no pathological lesion was found in the liver by LM. And IgA and MH antigen containing circling immune complexes were positive in sera by Raji cell assay, and moreover IgA and MH antigen was found co-depositing by the double stain techniques. These findings suggest that swine glomerulopathy is similar in appearance to human IgA nephropathy and MH antigen may contribute to the development of this nephropathy.

Animals↗
PubMed1990

Tubulointerstitial nephritis induced by Tamm-Horsfall protein sensitization in guinea pigs.

Experimental tubulointerstitial nephritis (TIN) was induced in guinea pigs by immunization with homologous Tamm-Horsfall protein (THP). This disease was characterized by focal interstitial mononuclear cell infiltration around the distal nephron segments with degeneration of renal tubular cells. Although concomitant granular immunoglobulin deposition on the tubular basement membrane and a rise of serum anti-THP antibodies were recognized, they were related to the severity of the lesion. Lymphocytes from lymph nodes of animals with TIN showed blast transformation in the presence of THP in vitro. Following the transfer of lymphocytes and spleen cells from guinea pigs with THP-induced TIN to nonimmunized animals, the recipient animals developed TIN 7 days later. These observations suggest that TIN induced in guinea pigs by challenge with homologous THP may, at least in part, be related to a cell-mediated immune response.

Animals↗
PubMed1990

Production of monoclonal antibody against human prostatic adenocarcinoma and its immunohistochemical properties.

We have generated a monoclonal antibody against prostatic adenocarcinoma, PC-Ab (IgM) was derived from a fusion using the fresh prostatic tissue of adenocarcinoma as the immunogen. Initial screening was performed by enzyme-linked immunosorbent assay (ELISA) on the soluble fraction of the immunogen. The specific analysis was performed by the avidin-biotin-complex immunoperoxidase method on paraffin-embedded sections of normal, benign and malignant neoplastic tissues from the prostate and various organs. PC-Ab reacted with well differentiated adenocarcinoma (83.3%), moderately differentiated adenocarcinoma (92.2%), and poorly differentiated adenocarcinoma (90.2%), respectively. According to classification by stage, the reaction rates with stage T0, T1, T2, T3 and T4 were 77.3%, 80.0%, 95.2%, 91.3% and 92.9%, respectively but no significant differences in the stages were seen among these groups. PC-Ab reacted with the epithelium of the normal prostate and benign prostatic adenoma, and human fetal tissues. Molecular weight and isoelectric point of the antigen recognized by this PC-Ab was estimated to be 57,000 daltons and 7.0, respectively. These results indicate that PC-Ab reacts with the antigen associated with human prostatic adenocarcinoma.

Adenocarcinoma↗
PubMed1986

[Complete remission obtained in advanced testicular cancer treated by etoposide (NK-171)].

A 38-year-old man was admitted to Nara Medical University Hospital on Feb.7,1983, because of swelling of the scrotal contents on the right side and elevated serum AFP, beta-HCG and LDH suggestive of testicular tumor. Right orchiectomy was carried out and a pathological diagnosis of embryonal cell carcinoma of the right testis (pT3N0M1) was made. The patient, upon evidence of multiple pulmonary metastases, was treated with a combination chemotherapy of cis-Diamminedichloroplatinum, vincristine and peplomycin. After three courses of combination chemotherapy, pulmonary metastases were decreased, but their foci persisted. The patient was then treated with Etoposide 62 mg/m2 daily for 5 days every three weeks, and after this course, complete remission of pulmonary metastases was obtained. The patient recieved 3 courses of Etoposide and retroperitoneal lymph node dissection, and has since shown no evidence of disease for 2 years and 4 months after surgery.

Adult↗
PubMed1985

Abortive infection with human cytomegalovirus induces an alteration of growth pattern: morphological changes with cytocidal effect in rabbit kidney epithelial cells. Brief report.

Rabbit kidney epithelial cells (RK13) exhibited a cytopathic effect (CPE) characterized by cell rounding after infection with human cytomegalovirus (HCMV). Although HCMV-specific immediate early and early antigens were detected by indirect immunofluorescence techniques, neither late antigens nor infectious progeny virus could be observed in virus-infected RK13 cells. HCMV-infected RK13 cells showed a prolonged doubling time and a decreased saturation density in cell growth compared to uninfected control cells. Moreover, colony forming ability (CFA) of virus-infected cells decreased by approximately 70 per cent compared to that of uninfected cells during the first 24 hours after infection. These results indicate that an abortive infection of RK13 cells with HCMV induces an alteration of growth pattern including morphological changes with cytocidal effect.

Animals↗
PubMed1985

[Effect of UFT on urinary bladder tumors in rats induced by N-butyl-N-(4-hydroxybutyl)nitrosamine].

The effect of combined tegafur and uracil (UFT) on the development of rat urinary bladder tumors induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) was studied. Two hundred F344 male rats were divided into 10 groups. Groups 1 to 5 were given 0.05% BBN in drinking water for the initial 8 weeks of the experiment, and Groups 6 to 10 were the controls of the prior 5 groups treated with BBN. UFT in commercial diet was administered at daily doses of 100mg (30.9 mg as FT-207) per kg of body weight in Groups 2 and 4 and 200 mg (61.7 mg as FT-207) per kg of body weight in Groups 3 and 5. Groups 2 and 3 received UFT throughout the period of the experiment, and Groups 4 and 5 for 12 weeks after 8 week treatment with BBN. All animals were sacrificed at 20 weeks, and studied histopathologically. In Groups 1 to 5, urinary bladder tumors developed in 20 of 20, 13 of 20, 6 of 20, 14 of 20 and 6 of 20, respectively. Incidences of tumors in the 4 groups treated with UFT were significantly lower than that in Group 1 treated with BBN alone. This result shows that UFT inhibits the development of urinary bladder tumors in rats induced by BBN.

Animals↗
PubMed1985

[Fundamental studies on intravesical instillation of cis-diamminedichloroplatinum for treatment of urinary bladder tumors. I: On the effects of intravesical instillation of cis-diamminedichloroplatinum in normal beagle dogs].

Cis-Diamminedichloroplatinum (II) (DDP) is one of the most effective agents in the treatments of advanced bladder cancer, but little is known of its local and systemic toxicity when it is instilled intravesically. The objectives of this experiment were to study the local and systemic toxicity of intravesical DDP in order to know whether intravesical DDP is applicable for prophylaxis and/or definitive treatment of superficial bladder cancers. Six female Beagle dogs were used for the 48-hour retention study and 2 mongrel dogs were used for the 3-hour study. Plasma and bladder platinum concentration were measured following intravesical DDP, and also histopathological examination, urinalysis, complete blood count and blood chemistry were performed in order to know the toxicity of intravesical DDP. Plasma platinum concentration was not elevated significantly and no remarkable changes were observed in blood examinations after intravesical DDP. Bladder tissue platinum concentration was significantly elevated up to 16.96 micrograms/g . wet after 3 hours DDP retention and 4.02 +/- 2.8 micrograms/g . wet after 48 hours retention in dogs. At present, intravesical instillation of DDP seems to have minimum local toxicity and no systemic toxicity, but further study is necessary for long term topical instillation of DDP.

Animals↗
PubMed1984

Dexamethasone enhances human cytomegalovirus replication in human epithelial cell cultures.

An epithelial human hepatoma cell line (PLC/PRF/5) and a primary epithelial human baby kidney (HBK) cell culture showed restricted growth of human cytomegalovirus (HCMV). Treatment of these two epithelial cell cultures with dexamethasone greatly enhanced their ability to support HCMV replication. Growth kinetic experiments and infectious center assay revealed that in both the hormone-treated cultures infectious progeny virus appeared earlier by 1 or 2 days and 5- or 10-fold more cells are able to produce infectious virus. There was an approximate 50- or 100-fold increase in virus yield compared to that in the untreated control cultures. Enhanced HCMV replication in the hormone-treated cultures was not due to differences in the cell growth or the virus adsorption and was supported by evidence of increased synthesis of HCMV-specific immediate early antigens and DNA.

Carcinoma, Hepatocellular↗