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T Mashimo

Publications and source records attributed to T Mashimo.

At least 109 records · Page 6Linked to original sources
PubMed1995

[Bladder tumor associated with von Recklinghausen's neurofibromatosis: a case report].

A 47-year-old female was admitted to our hospital complaining of macrohematuria. The patient had a history of von Recklinghausen's disease. Her skin showed multiple cafe-au-lait spots and neurofibromatosis. Thorough examinations were done. Urine cytology was positive. Intravenous pyelography and cystography demonstrated an irregular wall of the bladder. A computerized tomographic scan demonstrated a 7 cm nodular mass. Cystoscopy revealed a papillary tumor on the right lateral and anterior wall of the bladder. She was diagnosed as having a bladder tumor in von Recklinghausen's neurofibromatosis. Total cystectomy was performed. Histopathological diagnosis was transitional cell carcinoma with squamous cell carcinoma (Grade III, pT3N2N0). Fifty three cases of von Recklinghausen's disease in the literature were accompanied with malignancy.

Carcinoma, Squamous Cell↗
PubMed1995

[Change in serum prostate specific antigen values in men who had no evidence of prostate cancer on initial biopsy].

To determine the need for repeat prostatic biopsy, we retrospectively evaluated 19 men for longitudinal prostate specific antigen (PSA) for more than 20 weeks from initial biopsy. Their initial biopsy results revealed no evidence of prostatic cancer. They had no surgical therapy or hormone therapy after it. If they had a 50% increase in the PSA level from initial biopsy, we performed the second biopsy. Of the 5 men who had the second biopsy, 3 men had prostatic cancer.

Biopsy↗
PubMed1994

The alymphoplasia (aly) mutation co-segregates with the intercellular adhesion molecule-2 (lcam-2) on mouse chromosome 11.

A new spontaneous autosomal recessive mutation alymphoplasia (aly), which causes a systemic defect of lymph nodes and Peyer's patches, was mapped on mouse chromosome 11 by linkage analysis using (ALY x MSM)F1 x ALY backcross progeny (155 mice). The gene order and map distances on the chromosome were as follows (cM +/- SD); D11Mit14 (AntP91a), Krt-1 -(0.7 +/- 0.6)--D11Mit59--(1.9 +/- 1.1)--D11Mit52, D11Nds7 (Gfap)--(0.7 +/- 0.6)--aly, D11Mit10, D11Mit13 (Ace), D11Mit58 (Myla), lcam-2--(8.4 +/- 2.2)--D11Mit12. No recombinant was found among aly, D11Mit10, D11Mit13, D11Mit58 and lcam-2, suggesting the possible involvement of lcam-2 in the aly mutation. However, the nucleotide sequence of the lcam-2 gene of aly/aly mouse was identical to that of the control mouse. No difference was detected between aly/aly and the control mouse for expression of the gene by both Northern blot and reverse transcriptase polymerase chain reaction analyses. Furthermore, immunohistochemical analysis using a mAb revealed that the ICAM-2 protein was normally distributed in various tissues. These findings indicate that aly/aly mice do not suffer from defects of lcam-2. The four polymorphic microsatellite markers tightly linked with the aly gene will serve as admirable guideposts for a chromosomal walk to the aly gene.

Animals↗
PubMed1994

Low plasma lidocaine concentration does not affect oxygen uptake at awakening from isoflurane anesthesia.

To clarify the effects of lidocaine in plasma after epidural administration on oxygen uptake (VO2) at awakening from isoflurane anesthesia, we measured VO2 in 45 patients undergoing abdominal hysterectomy under four conditions: control group, intravenous normal saline; epidural group, 3 mg/kg of 1.5% lidocaine epidurally as a bolus; and groups CIV-A and CIV-B, continuous intravenous infusion of 2% lidocaine, 0.5 and 1 mg/kg, respectively, for 5 min followed by 30 micrograms.kg-1 x min-1. VO2 at both periods of steady state during anesthesia before lidocaine administration and awakening from anesthesia were measured using a mass spectrometer system during spontaneous breathing. At awakening, VO2 in the control, CIV-A, and CIV-B groups increased significantly (P < 0.02) from 142 to 262-328 mL.min-1 x m-2 which as more (P < 0.01) than that in the epidural group which increased from 166 to 159 mL.min-1 x m-2. These results indicate that epidural lidocaine prevents the increase in VO2 associated with arousal from isoflurane anesthesia. This effect is not due to the absorbed plasma lidocaine but due to the epidural neural block.

Adult↗
PubMed1994

Epidural lidocaine delays arousal from isoflurane anesthesia.

To clarify the effect of epidural lidocaine on arousal from inhaled anesthesia, we investigated the minimum alveolar anesthetic concentration at awakening (MAC-Awake) of isoflurane and the duration between discontinuance of isoflurane inhalation and arousal from anesthesia in 60 female abdominal hysterectomy patients. All patients received epidural catheterization and were randomly assigned to one of five groups. The control group, A, was given normal saline intravenously (IV) and epidurally. Group B was given 1 mg/kg of 2% lidocaine IV as a bolus. Groups C and D were given 0.5 and 1 mg/kg, respectively, of 2% lidocaine IV for 5 min, followed by 30 micrograms.kg-1.min-1. Group E was given 3 mg/kg of 1.5% lidocaine epidurally as a bolus. These doses of lidocaine or control saline were administered 15 min before the end of the surgical procedure. MAC-Awake values in Groups A, B, C, D, and E were 0.30% +/- 0.05%, 0.28% +/- 0.04%, 0.29% +/- 0.04%, 0.31% +/- 0.04%, and 0.18% +/- 0.05% (mean +/- SD), respectively. MAC-Awake in Group E was lower than in the other groups (P < 0.001). The duration until arousal in Group E (21.0 +/- 2.0 min) was longer than in Groups A, B, C, and D (12.6 +/- 1.8 min, 12 +/- 2.3 min, 13.3 +/- 2.5 min, and 14.3 +/- 2.7 min, respectively) (P < 0.001). Plasma lidocaine levels in Groups B, C, D, and E were 0.95 +/- 0.17 microgram/mL, 1.07 +/- 0.16 microgram/mL, 2.09 +/- 0.31 micrograms/mL, and 1.02 +/- 0.16 micrograms/mL, respectively. We conclude that analgesia produced by epidural lidocaine delays arousal from isoflurane anesthesia. Furthermore, lidocaine plasma levels are shown to be too low to cause any sedative effect, thus suggesting that postoperative pain may cause significantly faster arousal from anesthesia.

Adult↗
PubMed1994

Decrease in vecuronium infusion dose requirements by nicardipine in humans.

This study was designed to analyze quantitatively the interaction of nicardipine with vecuronium using a constant infusion technique. Forty-seven patients undergoing elective otolaryngeal surgery were anesthetized with isoflurane (1% end-tidal) and nitrous oxide (67%). Patients were randomly assigned to receive one of four doses of nicardipine (0, 1, 2, and 3 micrograms.kg-1.min-1). Vecuronium infusion dose requirement was determined as a constant infusion rate which maintained 90% depression of control twitch tension. Nicardipine significantly decreased the vecuronium requirement in a dose-dependent manner, i.e., the vecuronium doses were 0.70 +/- 0.03, 0.55 +/- 0.04, 0.42 +/- 0.04, and 0.37 +/- 0.05 micrograms.kg-1.min-1 at nicardipine doses of 0, 1, 2, and 3 micrograms.kg-1.min-1, respectively. Nicardipine also reduced both the plasma concentration of vecuronium to maintain the 90% depression and the total plasma clearance of vecuronium. The reversal of the vecuronium effect with neostigmine was not influenced by nicardipine. The results indicate that the vecuronium infusion dose requirements are reduced as much as 53% by a clinical dose of nicardipine.

Adult↗
PubMed1994

[Investigation of ultrasound guided systematic biopsy of the prostate].

From August 1991 to February 1993, a total of 114 men with mean age of 68 years underwent ultrasound guided systematic biopsy of the prostate. These patients were clinically suspected of having prostate cancer by elevated PA or digital rectal examination. Systematic biopsies were performed on two different sites of peripheral zone and transition zone of each lobe, and echographically detected hypoechoic area was also biopsied. There were 42 prostate cancers detected: 7 (30%) in 23 men between 50 and 59 years old, 17 (45%) in 38 men between 70 and 79 years old, 6 (55%) in 11 men more than 80 years old. Three (11%) were detected in 27 men with a PA level of less than 3.1 ng/ml, 39 (45%) were detected in 89 men with a PA level of no less than 3.1 ng/ml. Thirty-three (44%) were detected in 75 men with positive rectal examination. Non-palpable cancers were detected in 9 men. These results suggest that systematic biopsy may be useful and a sensitive means in detecting prostatic cancer.

Aged↗
PubMed1993

Ultrasonic diagnosis of 3,2'-dimethyl-4-aminobiphenyl induced tumors in the urogenital organs of F344 rats.

The usefulness of transabdominal ultrasonography in the diagnosis of 3,2'-dimethyl-4-aminobiphenyl- and testosterone propionate-induced tumors of the urogenital organs was evaluated in F344 rats. Seven mass lesions (1 ventral prostate, 1 dorsolateral prostate, 3 seminal vesicles, and 1 kidney) in the urogenital organs could easily be diagnosed concerning size and localization by ultrasound. Histological examination revealed a lesion in the ventral prostate to be an abscess and the other tumors to be malignant. Three hydronephroses by tumor invasion to the ureter, and six tumors in organs other than the urogenital organs could be detected by ultrasound. The threshold of malignant tumor detection by ultrasound was 7 mm in actual length. The size of the mass lesion estimated by ultrasound correlated well with the direct measurement (r = 0.96). Transabdominal ultrasonography is useful for diagnosing the localization of experimental tumors and accurately measuring their size in the urogenital organs of rats.

Adenocarcinoma↗
PubMed1993

Biodegradable poly(DL-lactic acid) formulations in a calcitonin delivery system.

A synthetic analogue of eel calcitonin, [Asu1, 7]-ECT, was incorporated into biodegradable poly(DL-lactic acids) with number-average molecular weights (Mn) of 1400-4400 by the melt-pressing technique. The in vitro release of drug from a parabolically degradable poly(DL-lactic acid) with Mn = 1400 showed an initial burst release and completed the release in 3 d from the start of the test. The drug release from a Mn = 4400 polymer with an S-type degradation pattern was kept at 14 +/- 5 units/d for an experimental period of 24 d.

Amino Acid Sequence↗
PubMed1993

Alterations in pain threshold and psychomotor response associated with subanaesthetic concentrations of inhalation anaesthetics in humans.

We studied the effects of six inhalation anaesthetics at subanaesthetic concentrations of 0.2 MAC on pain threshold and psychomotor function in six healthy volunteers. When compared with 100% oxygen inhalation, nitrous oxide and methyoxyflurane significantly increased pain threshold as measured by a radiant heat algometer, and prolonged the response time to auditory stimuli. In contrast, halothane, enflurane, isoflurane and sevoflurane produced prolongation of the response time to auditory stimuli but did not influence pain perception. The pain threshold with nitrous oxide remained significantly increased 30 min after its discontinuation, while the response time returned to the preinhalation value. We conclude that nitrous oxide and methoxyflurane possess both analgesic and hypnotic actions but halothane, enflurane, isoflurane and sevoflurane do not have an analgesic action at subanaesthetic concentrations, and the analgesic action of nitrous oxide persists after its elimination.

Adult↗
PubMed1993

[Symptoms and signs of benign prostate hypertrophy (BPH)].

Clinical characteristics of BPH were investigated in the relationship among prostate volume estimated by transrectal sonography, symptoms by questionnaire, residual urine volume, and voiding force evaluated by uroflowmetry. There was no apparent relationship among them, which might be caused by the poor reproducibility of residual urine volume, the difficult enumeration of the symptoms, contamination of other diseases of which voiding disorder is correlated with aging and other unknown factors. Under such a situation, this disease should be treated as a BPH syndrome. Moreover we propose that BPH syndrome should be classified into three types; type 1: symptomatic BPH without enlarged prostate, type 2: asymptomatic BPH with enlarged prostate and type 3: symptomatic BPH with enlarged prostate.

Aged↗
PubMed1993

[Age-related changes in the size and shape of the prostate observed by transrectal ultrasonography].

To elucidate the change with aging in prostatic morphology, 447 cases without acute diseases and prostate cancer of the first visit from January 1988 to December 1990 were examined by transrectal ultrasonography. Total weight of the prostate, area of maximum section, lateral and anteroposterior diameter on the maximum section and supero-inferior diameter were evaluated. The total weight of the prostate was not found to be correlated with aging. The total weight of the prostate showed a high variation with aging. Prostate growth with more than 30 g was greater in the fifties and increased gradually thereafter. Similar findings were observed for antero-posterior diameter on the maximum section and supero-inferior diameter. With aging, the total weight of the prostate in 20-30% of the patients showed an increase while in 30-40% of the patients, no increase. The total weight of the prostate increased in the fifties with subsequent gradual increase in the sixties. According to prostate shape, antero-posterior diameter on the maximum section and supero-inferior diameter was related to the weight of the prostate.

Adult↗
PubMed1993

[The characteristics of hormone responsiveness of glandular epithelium and stroma in male accessory sex organs].

We investigated the hormonal responsiveness of gland and stroma in the male accessory sex organs (ventral prostate, dorsolateral prostate and seminal vesicle). Immature rats (3 weeks old) were castrated and left untreated for 4 weeks and then distributed at random into 3 groups, A, B, C. The rats in groups A, B and C were injected subcutaneously with 0.2 ml of soybean oil, 5 alpha-dihydrotestosterone (DHT, 500 micrograms/day) or estradiol-17 beta (E2-17 beta, 5 micrograms/day), respectively, for 14 days before they were killed. DHT administration in prepuberal castrates stimulated collagen synthesis and accumulation in the stroma of male accessory sex organs as well as the proliferation and differentiation of the glandular epithelium in these organs. In E2-17 beta treated rats, the glandular epithelium of ventral prostate and seminal vesicle had mostly a single layer structure, but the glandular epithelium of dorsolateral prostate had a mostly multilayer structure. On the other hand, in E2-17 beta treated rats, the EMBP content, an indicator of glandular epithelium differentiation in male accessory sex organs, did not increase even in the dorsolateral prostate which showed a multilayer gland epithelium. Collagen synthesis and accumulation in the seminal vesicle was stimulated by E2-17 beta treatment several times as much as in the ventral and dorsolateral prostate. Histological investigation demonstrated that the seminal vesicle in prepuberal castrates treated with E2-17 beta resembled that of fibromuscular type human benign prostatic hyperplasia.

Animals↗
PubMed1993

Time-related differential effects of epidural morphine on the neuraxis.

To clarify the site and potency of the analgesic and anesthetic action of epidurally administered morphine, we investigated the effects of epidurally and intravenously administered morphine (100 micrograms/kg) on change in the pressure pain threshold (PPT) and the minimum alveolar concentration (MAC) of halothane. Epidural morphine (EM) increased PPT significantly (P < 0.01) at the points around the surgical incision by 40% and 60% from baseline compared with intravenous morphine (IM) with which PPT remained at baseline 1 and 2 h after administration, respectively. Duration of analgesia was much longer in EM than in IM (18 h vs 1.7 h). EM increased PPT from preoperative value at the forehead and the points around the surgical incision by 9.9% and -24.9% at 1 h, by 10.9% and 3.8% at 4 h, and by -19.5% and -50.4% at 12 h after administration at mean values, respectively. Halothane MAC in EM and IM were 0.54% and 0.57%, respectively, 40 min after administration. Halothane MAC in EM at 4 h and 12 h after administration were 0.45% and 0.70%, respectively. The results suggest that EM provides long-lasting analgesia by its time-related differential effects on the neuraxis.

Adult↗
PubMed1992

Volatile anesthetics-induced activation phenomena of alpha-chymotrypsin-catalyzed hydrolysis.

The rates of hydrolysis of p-nitrophenyl acetate (pNPA), p-nitrophenyl propionate (pNPP), p-nitrophenyl butanate (pNPB), and p-nitrophenyl valerate (pNPV) catalyzed by alpha-chymotrypsin (alpha-CHT) were measured with and without volatile anesthetics at 25.0 degrees C. Halothane activated the hydrolysis of pNPA and pNPP, meanwhile inhibited that of pNPB and pNPV. The activation phenomena were explained by the existence of a 1:1 enzyme-anesthetics complex and the opening of an activated pathway. The rate constant of pNPA hydrolysis catalyzed by alpha-CHT of the activated pathway kA by halothane was 0.269 s-1, whereas that of the normal pathway was k0 0.093 s-1. The free energy of activation was stabilized at 0.64 kcal/mol by halothane. The mechanisms of the activation and inhibition are discussed in terms of the molecular size of the substrate and anesthetics.

Anesthetics↗
PubMed1992

The solubility of volatile anaesthetics in water at 25.0 degrees C using 19F NMR spectroscopy.

Anaesthetic concentration is very important for the quantitative treatment of anaesthesia theory. Traditionally concentration values have been derived from the water/gas partition coefficient. However, the values from many investigators show discrepancies. This study reports the accurate solubility of methoxyflurane (9.1 mM), halothane (18.0 mM), enflurane (11.9 mM) and isoflurane (13.5 mM) in water at 25.0 degrees C using 19F NMR spectroscopy. The method has advantages in that the dissolved molecule in solution can be separately quantified from undissolved anaesthetic. Saturated solutions of the anaesthetic agents were prepared in situ in a NMR tube to avoid pressure and temperature changes in the solution.

Anesthetics↗
PubMed1992

Prolongation of canine epidural anesthesia by liposome encapsulation of lidocaine.

The purpose of our study was to produce a long-acting lidocaine by using a liposome that would entrap the drug. Egg yolk phosphatidylcholine and cholesterol were used as liposome materials. After epidural administration, the pharmacodynamics and pharmacokinetics of liposomal and free lidocaine were studied in 20 dogs. Two percent liposomal or free lidocaine (3.0 mL) was injected into the lumbar epidural space. Nerve blocking effects were estimated by measuring somatosensory evoked potentials. Recovery time from the epidural block in the liposomal lidocaine group (170 +/- 49.5 min) was approximately three times longer than that in the free lidocaine group (61 +/- 18.1 min). The areas under the drug concentration-time curves (AUC0-infinity) and time to maximal concentration (Tmax) in the liposomal lidocaine group were significantly larger than those in the free lidocaine group. These results suggest that the prolongation of epidural blockade by liposomal lidocaine is caused by a slow release of the drug from liposomes. The present study suggests that liposomal lidocaine can be used as a long-acting local anesthetic.

Amines↗