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T Horiguchi

Publications and source records attributed to T Horiguchi.

At least 109 records · Page 6Linked to original sources
PubMed1991

[Effect of endotoxin on plasma angiotensin-converting enzyme in dogs].

We calculated angiotensin converting enzyme (ACE) index (ACE/CO) to exclude the influence of pulmonary perfusion and investigated the relationship among ACE, ACE index, hemodynamic changes in 6 endotoxin dogs. Systemic arterial pressure and cardiac output (CO) decreased significantly after 3 mg.kg-1 of endotoxin administration, but neither pulmonary arterial pressure nor pulmonary arterial wedge pressure changed. Lung wet/dry ratio was higher. Although endotoxin administration caused the pulmonary capillary endothelial damage in this experiment, plasma ACE showed a nonsignificant increase. The main reason may be related to the reduction of surface area of pulmonary capillary endothelial cells caused by the decrease in cardiac output. The increased ACE index lasted for 15 to 90 min and began to return to baseline at 120 min after endotoxin administration. We conclude that ACE index is more useful than plasma ACE as an early marker of the pulmonary capillary endothelial damage induced by endotoxin.

Animals↗
PubMed1991

[A statistical analysis of serum sialyl Lewis X-1 (SLX), CEA, SCC and NSE levels in patients with lung cancer].

Serum SLX, CEA, SCC and NSE levels were serially measured in 266 patients with lung cancer and compared with those in 345 patients with benign respiratory disorders (BRD). The positive rate for CEA in lung cancer (44.4%) and the false-positive rate in BRD (15.3%) were the highest among the 4 markers. The positive rate for SLX in lung cancer (32.0%) was lower than that of CEA, while the false-positive rate for SLX in BRD (7.2%) was lower than that of CEA. The positive rate for SLX was highest in adenocarcinoma and correlated better with the clinical stages than did CEA. SCC and NSE were specifically elevated in squamous cell carcinoma and small cell carcinoma, respectively. Using these 4 markers, only 70.2% of patients were correctly diagnosed as having lung cancer or BRD. In monitoring treatment effect, only SLX showed a statistically significant correlation with regression and progression in adenocarcinoma, while NSE and SLX showed such a correlation in small cell carcinoma. Serum tumor markers seem to be less sensitive for the diagnosis of lung cancer than chest X-ray and sputum cytology, indicating that a search for more specific markers is still required. However, in monitoring treatment effect, SLX appeared to be suitable for adenocarcinoma, while NSE and SLX seemed to be useful in small cell carcinoma.

Adenocarcinoma↗
PubMed1991

[Effect of isoflurane on muscle relaxation in a patient with myotonic dystrophy].

We did anesthetic management by isoflurane for total thyroidectomy under the neuromuscular transmission monitoring in a patient with myotonic dystrophy. In three patients without neuromuscular disorders, T1 was 85% of control and fade was not observed, while in this case T1 was 40% of the control and TOFR was decreased to 50%. We conclude that isoflurane has a good muscle relaxation effect in this disease and, we could manage without administering any muscle relaxants.

Adult↗
PubMed1991

[Effect of short-term administration of medroxyprogesterone acetate on side reactions of combination chemotherapy with ADR, VDS and CDDP in primary lung cancer].

The effect of short-term (10 days) Medroxyprogesterone acetate (MPA) administration on side reactions of combination chemotherapy with ADR, VDS and CDDP for primary lung cancer was studied by comparisons of MPA administration group (20 cases) with non administration group (30 cases). 1) Frequency of vomiting, duration of nausea and body weight loss were significantly improved in MPA administration Group (p less than 0.01). 2) Leukocyte and neutrophil counts in MPA administration group especially 7-10 days after of chemotherapy were maintained higher than these of non administration group (p less than 0.05). 3) Major side effects including thromboembolism in MPA administration group had not been observed. These results indicated that short-term MPA administration was relatively safe and effective in combination chemotherapy including CDDP.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

[The evaluation of incremental positive end-expiratory pressure on right ventricular hemodynamics as determined by the thermodilution technique].

Effects of incremental positive end-expiratory pressure (PEEP) on right ventricular (RV) hemodynamics were studied in 10 patients undergoing coronary artery bypass grafting, abdominal aneurysmectomy and partial hepatectomy, using Swan-Ganz catheter mounted with the rapid response thermistor. PEEP was increased from 0 (baseline) to 15 cmH2O with increment of 5 cmH2O, and right ventricular ejection fraction (RVEF), RV end-diastolic volume (RVEDV), RV end-systolic volume (RVESV), and cardiac output (CO) were computed with a thermodilution technique at each PEEP. At 15 cmH2O PEEP, RVEF, RVEDVI and RVESVI were comparable with the baseline, while right arterial pressure, RV peak systolic pressure and mean pulmonary arterial pressure increased significantly compared with the baseline. Increased afterload of RN caused by PEEP did not affect RV contractility. Decreased cardiac and stroke volume indices were attributed to the decrease of preload caused by the increase of intrathoracic pressure. We conclude that PEEP at 5 to 15 cmH2O does not influence right ventricular hemodynamics, and RVEDV is a reliable index to monitor RV hemodynamics instead of right arterial pressure to determine optimal PEEP.

Aged↗
PubMed1990

[Weibull statistical analysis of bending strength data measured either in air or in distilled water for sintered hydroxyapatite ceramics coated on the metal substrate].

To assess the effects of H2O on the fracture stress of sintered hydroxyapatite (HAP) ceramics prepared by procedures similar to those used for HAP coated on the metal substrate, four-point bending tests were carried out at 0.5 mm/min either in air (20 C, R.H. 73%) or in distilled water (37 degrees C). Then, strength data obtained were analyzed using two-parameter weibull statistics. In each condition, the bending strength data gave a good fit to single-mode weibull distribution. Weibull analysis of the data gave weibull parameter m = 7.8, sigma 0 = 26.2 MPa in air and m = 8.1, sigma 0 = 18.5 MPa in distilled water, which were calculated assuming a surface flaw model. The mean value of bending strength was 27.3 MPa in air and 18.2 MPa in distilled water. These results indicated that a corrosive environment such as H2O affects fracture stress when measured at a constant stress rate. This effect is considered to be caused by slow crack growth of cracks, occurring at a loading level lower than those at which specimens will fail. Using the weibull distribution function estimated in this study, the effects of both dimension of specimen and stress distribution in the specimen on the mean fracture stress have been predicted.

Air↗
PubMed1990

[Estimation of fatigue parameter and life-time prediction using SPT diagram for hydroxyapatite coating layer in 37 degrees C distilled water].

Lifetime and survival probability of brittle materials under given conditions of stress distribution, environment and component size can be predicted using an SPT (Strenght-Probability-Time) diagram. The SPT diagram for sintered hydroxyapatite (HAP) coated on the metal substrate via the fused glass was drawn and the safe working stress in 37 degrees C distilled water was estimated. The dynamic fatigue test carried out in 37 degrees C distilled water gave the fatigue parameter n = 19 for sintered HAP. This parameter is constant except that it depends on material and environment, and the greater the value of n, the greater the resistance to fatigue failure. For sintered HAP, therefore, the resistance to fatigue failure under this wet condition is low. To draw the SPT diagram, anchor points were taken from the fracture stress and time-to-failure data measured at 1 mm/min. The SPT diagram obtained suggested that a lifetime of 20 years with survival probability of 99.9% required the safe working stress of less than 3.2 MPa. The effects of accuracy of fatigue parameter on the uncertainty in SPT diagram were estimated.

Corrosion↗
PubMed1990

[Apatite-collagen complex. Preparation of a new apatite-collagen complex].

A new apatite-collagen complex was prepared in calcium beta-glycerophosphate solutions at pH 8.50. For this preparation, reconstituted type I collagen was cross-linked with phosvitin in the presence of alkaline phosphatase by use of a cross-linking agent of dimethyl suberimidate. After two weeks of immersion in daily-renewed solution of calcium beta-glycerophosphate, the complex contained apatite approximately two times the modified collagen in weight. When viewed in a scanning electron microscope, needle-like crystals precipitated densely on the collagen fibrils. However, in some portion of the complex, dot-like precipitate was observed as well. X-ray diffraction and IR analyses of the complex suggested that the apatite precipitated on the collagen fibrils was very similar to bone mineral in two aspects, crystallinity and carbonate content.

Apatites↗
PubMed1990

[Progress and obstacles in chemotherapy and combined modality treatment of small cell lung cancer].

In order to assess the development of treatment of small cell lung cancer (SCLC), we analyzed a total of 183 patients who had been entered into our protocol studies since 1976. Between 1976 and 1981, 39 patients (20 LD and 19 ED) received COMP, a 4-drug combination of cyclophosphamide (CTX), vincristine (VCR), methotrexate and procarbazine. During the period, chest irradiation (RT) was optimal for those with LD. Between 1981 and 1986, 112 patients (56 each of LD and ED) were treated with a cyclic alternating chemotherapy (CT) of COMP and VAN, a 3-drug combination of etoposide (VP-16), adriamycin (ADM) and nimustine. In this study, we randomized patients with LD either to receive CT alone or CT plus RT of 40 Gy to assess the role of RT in the treatment of LD. Thereafter, a pilot study of CAV-PVP hybrid CT has been conducted in 32 patients (16 each of LD and ED), in which CTX, ADM and VCR were given on day 1 (CAV), and cisplatin on day 8 and VP-16 on days 8 and 9 (PVP). RT was administered mandatory to LD in this study.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Small cell lung cancer; a retrospective analysis of results of chemotherapy and chemo-radiotherapy].

In order to assess the development of treatments and the curability of small cell lung cancer, we analysed a total of 239 patients entered in our protocol study since 1976. Median survival time was 68 weeks for 127 patients with limited disease and 48 weeks for 112 with extensive disease. Three-year survival rate was 18% for those with limited disease, whereas it was only 5% for extensive disease. The median survival time and long-term disease-free survival rate has been improved with an introduction of aggressive chemotherapy including new drugs such as etoposide and cisplatin. Chest irradiation in addition to intensive chemotherapy played a substantial, but not significant, role for prolonging patient survival in those with limited disease. Nevertheless, the pace of therapeutic advances has been slowed and appears to reach a plateau. In this paper, the authors try to find some obstacles in the treatment of the disease, and to indicate some strategies to gain a progress.

Aged↗
PubMed1990

[EEG analysis of the effectiveness of the benzodiazepine antagonist RO 15-1788 after diazepam sedation].

In ten volunteers given diazepam, a new diazepam antagonist RO 15-1788 was administered and the effectiveness of this drug was analyzed on EEG. EEG electrodes were attached at C3 and C4 taking right and left ear lobes as indifferent electrodes. EEG trend monitor used by us was equipped with a Fourier analyzer as well as a conventional EEG recorder. EEG was recorded first for about 15 minutes at rest with eyes closed, followed by intravenous injection of 10 mg diazepam. At the end of the test, the antagonist, RO 15-1788 0.5-0.8 mg was administered. Slow waves and alpha waves were frequently found at rest with eyes closed. After diazepam administration, however, power spectrum percent in rapid waves (13-17.5 Hz) mainly consisting of beta waves increased from 8.0 +/- 1.3% (mean +/- SE) to 19.9 +/- 2.2%. These changes were statistically significant (P less than 0.05). At the end of procedures RO 15-1788 was administered and percent of power spectrum in beta waves decreased from 17.4 +/- 2.8% to 9.5 +/- 1.5%. These changes were also statistically significant (P less than 0.05). The sedative effect of diazepam may be evaluated by monitoring these rapid waves since the antagonizing effect of RO 15-1788 is demonstrated on EEG.

Adult↗
PubMed1989

Uterine vascular resistance during compression of the umbilical arterial and/or venous circulation in sheep.

Total umbilical cord occlusion and selective occlusion of the umbilical arteries and veins is associated with changes in uterine blood flow. In the present study, the resistance to uterine blood flow during selective occlusions of the umbilical arteries and/or veins was analysed in five chronically instrumented pregnant sheep in the last third part of pregnancy. An occluding device which allows separate occlusion of umbilical veins and arteries was applied to the umbilical cord. Median uterine artery blood flow was measured using an electromagnetic flow meter. Maternal pressures were measured in a branch of the uterine artery and vein. Two occlusions of the umbilical veins and/or arteries with a duration of 30-60 s were performed in each animal. Selective occlusion of the umbilical arteries resulted in a small increase in uterine blood flow from 637 +/- 79 ml/min during control toward 664 +/- 77 ml/min at the end of occlusion (p less than 0.05). Uterine perfusion pressure (uterine arterial pressure - uterine venous pressure) did not change. No changes were observed in calculated uterine vascular resistance (Poiseuille equation). Selective occlusion of the umbilical veins on the other hand caused a decrease in uterine blood flow from 617 +/- 75 ml/min during control to 546 +/- 69 ml/min at the end of occlusion (p less than 0.001), and a return to control value at 1 min after occlusion. The uterine perfusion pressure increased from 40.1 +/- 6.8 mmHg during control to 42.8 +/- 7.0 mmHg at the end of occlusion (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Lectin peroxidase conjugate reactivity in acquired cystic disease of the kidney.

The origins of acquired cysts, hyperplastic epithelia of cyst walls, and renal cell carcinomas were investigated by evaluating their lectin conjugate reactivity. Paraffin-embedded blocks from 9 patients with acquired cystic disease were examined by the high-sensitivity lectin-antilectin immune peroxidase method. 11-176 lesions in each patient, 690 lesions in total, were stained both with Tetragonolobus lotus lectin (T) and peanut lectin (P); the former is specific for proximal tubules and the latter for distal tubules and collecting ducts. Out of 606 acquired cysts with single-layered epithelia, 559 (92.2%) were positive for T and negative for P, and 66 out of 75 (88.0%) cysts with hyperplastic multilayered epithelia were positive for T and negative for P. Three out of 4 solid adenomas and, to varying degrees, 5 renal carcinomas revealed the same reaction. These results suggest that almost all cysts accompanying acquired cystic disease of the kidney, including those with single-layered and multilayered epithelia, as well as solid adenomas and renal cell carcinomas, are derived from proximal tubules.

Adult↗
PubMed1989

[Self-setting apatite cement. 6. Possibility as bone substitute].

Self-setting apatite cement was investigated to evaluate its use as a possible bone substitute in the rat femur. The implant sites were recovered at intervals up 12 weeks postoperatively and investigated by the use of x-ray diffraction, contact microradiography, light and electron microscopy. By x-ray diffraction analysis, the cement placed for at least one day in the medullary canal of rats was found to be completely converted to a set phase of hydroxyapatite resembling the main inorganic phase of bone. In any specimens prepared at 1, 4, 12 weeks after implantation, no appreciable foreign body response was observed in the tissue around the set cement. At four weeks after implantation the set cement was in tight contact with the newly formed bone which appeared to involve osteocytes in lacunae and osteoblastic cells on its surface. At twelve weeks after implantation, the newly formed bone tended to grow into the interior of the set cement. With scanning electron microscopy, the newly formed bone was found to be directly deposited on the set cement. The newly formed bone consisted of fine needle-like crystals. These results strongly suggest that this cement is well tolerated by bone tissue and osteogenesis when used as a bone substitute. The advantage of the present material as a promising bone substitute is that it can be filled in surgical or traumatic bone defect as a slurry or paste.

Animals↗
PubMed1989

[Self-setting apatite cement. 8. Dissolution and remineralization behavior of 45Ca-apatite cement].

Self-setting apatite cement hardens into a mass of single phase apatite when mixed with diluted phosphoric acid. Structurally this mass consists of two types of apatite, i.e. the seed apatite used as a setting accelerator and the matrix apatite formed afterward in the reaction of dicalcium phosphate dihydrate (DCPD) and tetracalcium phosphate (Te-CP). To investigate the dissolution behavior of self-setting apatite cement in detail, two types of 45Ca labeled apatite cement were prepared. In one, the seed apatite was labeled with 45Ca (45Ca-HAp cement) and in the other the matrix apatite was labeled with 45Ca through use of 45Ca-DCPD (45Ca-DCPD cement). Solubility, estimated from the concentration of 45Ca released in 1 mM of organic acid (e.q. acetic, lactic, or citric acid) with initial pH adjusted to 4.0 at 37 degrees C, was approximately zero for 45Ca-HAp cement, whereas the solubility of 45Ca-DCPD cement was approximately the same as unlabeled cements used so far. This finding suggests that dissolution of the matrix apatite governs dissolution of the set cement, though comparison of X-ray diffraction patterns and electron micrographs of the seed apatite and apatite in the set cement showed no essential difference in crystallinity and crystal shape. The fact that the matrix apatite was formed by enveloping the seed apatite may account for the preferential dissolution of matrix apatite. In synthetic saliva labeled with 45Ca having a degree of supersaturation with respect to apatite comparable to rest saliva, 45Ca concentration in solution decreased once the cement pellet was introduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Apatites↗
PubMed1989

[Self-setting apatite cement. VII. Barium-apatite as radio-opaque medium].

Addition of barium hydroxyapatite (BaAp) successfully bestowed clinically acceptable radioopacity to the self-setting apatite cement consisting of an equimolar mixture of tetracalcium phosphate and dicalcium phosphate dihydrate. To accelerate the setting reaction which was retarded by Ba2+ released from BaAp at a lower pH during first stage of spatulation with 20 mM phosphoric acid, calcium hydroxyapatite (CaAp) was added to the cement mixture. At about 20 wt% of BaAp and 20 wt% CaAp, the setting reaction proceeded at a neutral or weak alkaline pH, which is one of the most promising aspects of the self-setting cement and assures that this type of cement may be the least irritating of the dental cements presently available. The cement spatulated at L/P = 0.4 set within 10 minutes and its radiopacity was comparable to or more than that of tooth enamel. The wet compressive strength of the set cement stored for one day in synthetic saliva at 37 degrees C was approximately 100 kgf/cm2. Although this value is almost one fourth that of 40 wt% CaAp cement, this cement appears to be strong enough to apply as root canal filling material.

Barium↗