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T Mashimo

Publications and source records attributed to T Mashimo.

At least 19 recordsLinked to original sources
PubMed1995

NOC, a nitric-oxide-releasing compound, induces dose dependent apoptosis in macrophages.

The ability of exogenous nitric oxide (NO) to induce apoptosis in macrophages was analyzed using NOC, a NO-releasing compound, as a source of NO. Exogenous NO was shown to induce apoptosis in a dose dependent manner. Quantitative analysis revealed that the amount of NO required to induce apoptosis in more than half of macrophages exposed was 100 times larger than that for endogenous NO-induced apoptosis. NOC proved to be a convenient and useful tool for investigation of apoptosis related to NO.

Animals↗
PubMed1995

Pulmonary resistance in dogs: a comparison of xenon with nitrous oxide.

Xenon (Xe) may cause an increase in airway resistance due to its high density and viscosity. The object of this study was to examine the effects of Xe on pulmonary resistance using dog models with normal and methacholine-treated airways. During anaesthesia 22 mongrel dogs' tracheas were intubated and the lungs were mechanically ventilated with 70% N2/30% O2 as a control gas. The gases 70% nitrous oxide (N2O), 50% N2O, 70% Xe and 50% Xe were administered in a random order for 25 min. Bronchoconstriction was produced by a continuous infusion of methacholine, 0.22 mg.kg-1.hr-1. Pulmonary resistance (RL) was calculated by the isovolume method using flow at the airway opening, volume and transpulmonary pressure. In normal dogs, RL breathing 70% Xe (mean +/- SEM, 0.84 +/- 0.12 cm H2O.L-1.sec-1) was greater (P < 0.05) than with 70% N2O, 50% N2O or control gas (0.61 +/- 0.08, 0.59 +/- 0.06 and 0.62 +/- 0.06 cmH2O.L-1.sec-1). Breathing 50% Xe the RL (0.77 +/- 0.10 cmH2O.L-1.sec-1) was not different from 50% N2O or control. Methacholine infusion increased RL 3.92 +/- 1.98 (mean +/- SD) times. The RL breathing 50% Xe (2.55 +/- 0.44 cmH2O.L-1.sec-1) was not greater than during 50% N2O or control (2.08 +/- 0.33 and 2.13 +/- 0.33 cmH2O.L-1.sec-1) in methacholine-treated dogs. The data suggest that inhalation of high concentrations of Xe increases airway resistance, but only to a modest extent in dogs with normal or methacholine-treated airways.

Airway Resistance↗
PubMed1995

Analgesic and hypnotic effects of subanaesthetic concentrations of xenon in human volunteers: comparison with nitrous oxide.

The purpose of this study was to examine the effects of xenon and nitrous oxide in equipotent doses of 0.3 MAC on pain threshold and auditory response time in six healthy male volunteers. Compared with 100% oxygen inhalation, xenon and nitrous oxide significantly increased the pain threshold as measured by a radiant heat algometer. There was no significant difference in analgesic effects between xenon and nitrous oxide. Xenon significantly prolonged the response time to auditory stimuli compared with 100% oxygen, but nitrous oxide did not. The inhibitory effect of xenon on the auditory response time was significantly greater than that of nitrous oxide. The same six volunteers were studied to test if naloxone antagonized analgesia induced by xenon or nitrous oxide. The analgesic effects of xenon and nitrous oxide did not differ with or without naloxone.

Adult↗
PubMed1995

Fourteen anonymous DNA markers of laboratory rats identified with arbitrarily primed polymerase chain reaction (AP-PCR).

In order to develop genetic markers in rats, arbitrarily primed polymerase chain reaction (AP-PCR) was performed with single primers originally designed for microsatellite loci, instead of primers with short-sized and arbitrary nucleotide sequences. Each primer generated reliable and reproducible segments under optimal conditions. The fourteen amplification products have been successfully mapped to rat chromosomes by either linkage analysis using backcross progeny or chromosomal assignment with somatic cell hybrids. All of the loci were located on different chromosomes from those of the microsatellite loci, suggesting that sequence-specifically designed single primers can produce anonymous segments of genomic DNA showing polymorphisms. These markers should contribute to finding linkages for traits of interest in rats.

Animals↗
PubMed1995

Eosinophils infiltration in the rat seminal vesicle associated with estradiol-17-beta-related stromal proliferation.

We performed a histological quantitative analysis of collagen and smooth muscle in seminal vesicle (SV) stroma after Estradiol-17 beta (E2) administration to the immature castrated rat. On day 14 after E2 administration, collagen and smooth muscle had increased approximately five and fifteen times, respectively, over the baseline of day 0. On day 28 (14 days after the cessation of E2 administration), smooth muscle decreased to the same level as that on day 7, but collagen did not decrease during the 14 days after the cessation of E2 administration. As the proliferation of stroma, the infiltration of eosinophils was seen in the perigrandular stroma that consisted of rich collagen. The number of infiltrated eosinophils increased exponentially in the period in which collagen proliferated. But in the peripheral stroma which consists of rich smooth muscle, no eosinophil infiltration was seen. These results suggest that eosinophil infiltration into SV is related to E2 administration and to stromal proliferation, especially to collagen proliferation in this condition.

Animals↗
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↗
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

[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↗
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↗
PubMed1992

Segmental analgesic effect and reduction of halothane MAC from epidural fentanyl in humans.

To clarify the site of action of epidural fentanyl, we compared the effects of epidural and intravenous fentanyl on the change in pressure pain threshold (PPT) and the minimum alveolar concentration (MAC) of halothane. Seventy patients who underwent gastrectomy in the PPT study group and 84 female patients who underwent hysterectomy in the MAC study group were assigned randomly to seven groups in each study. The seven groups each received a bolus injection of 1, 2, or 4 micrograms/kg of fentanyl, either intravenously or epidurally, and of saline solution epidurally. Compared with intravenous fentanyl, epidural fentanyl significantly increased (P less than 0.01) PPT around surgical incisions by approximately 50%, 100%, and 150% of preadministration levels 1 h after administration of 1, 2, and 4 micrograms/kg, respectively, and significantly reduced (P less than 0.05) halothane MAC at the same doses. These data suggest that the more potent analgesic and anesthetic effects of epidural fentanyl, compared with intravenous fentanyl, are due mainly to the segmental analgesia produced by its spinal analgesic action.

Adult↗
PubMed1992

[Prostatic specific antigen (PA) in mass screening for prostate cancer].

The usefulness of prostatic specific antigen (PA) was compared with that of prostatic acid phosphatase (PAP). PA was determined in the serum of 2,183 patient examined by the mass screening for prostate cancer from 1987 to 1990. The serum samples of these patients were obtained from our serum bank. PA was measured by the E test "TOSOH" II (PA). The relationship of PA and PAP to prostate size estimated by digital rectal examination (DRE) and ultrasound tomography (US), and age was investigated. PA and PAP correlated with aging and prostate size estimated by DRE. However PA was more apparently related with these things. The correlation between PA and prostatic size estimated by US was relatively high (r = 0.53), but the correlation between PAP and prostate size estimated by US was low (r = 0.20). When the upper limit of normal range was set at 6.0 ng/ml, the sensitivity, specificity and efficiency was 64%, 97% and 62%, respectively. PA was more sensitive than PAP and could be more useful since none of the patients with prostate cancer was PAP positive and PA negative. We conclude that PA should be a reliable tumor marker in our mass screening system.

Acid Phosphatase↗