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Biomedical subjects

T Negishi

Publications and source records attributed to T Negishi.

At least 55 records · Page 3Linked to original sources

Chronic inhalation exposure and phospholipids in lung surfactant and tissue.

Golden hamsters were exposed to 2 mg/m3 coal fly ash for 180 days. The exposure raised the phospholipid level in the tissue, whereas no such elevation was observed in the surfactant. Increased phospholipid in the tissue is thought to reflect the accumulated surfactant in type II cells. Fatty acid composition analysis indicated an increase of arachidonic acid in the surfactant and increases of palmitic acid and arachidonic acid in the tissue. In conclusion, the pulmonary surfactant high in fluidity was stored in the lung tissue more than control, and the surfactant was secreted into the alveoli normally.

Administration, Inhalation↗

Antihypertensive effects, determined by a telemetry method, of trichloromethiazide and 7-O-ethylfangchinoline, a derivative of tetrandrine, in spontaneously hypertensive rats.

1. The antihypertensive effects of 10 mg/kg trichloromethiazide (TCM), 10 mg/kg 7-O-ethylfangchinoline (7-O-EFC) and the combination of these drugs given orally once daily for 2 weeks were investigated by measuring the blood pressure (BP), heart rate (HR) and activity in conscious, freely moving spontaneously hypertensive rats (SHR) fitted with a telemetry device. 2. Clear diurnal rhythms of the HR and activity in synchrony with the light/dark cycle were observed during therapy, whereas the BP rhythm was obscure. 3. Alone, TCM and 7-O-EFC produced slight and insignificant reductions of 24h mean BP, whereas in combination they produced an additive and significant BP reduction, compared with the vehicle-treated controls, from the third day of therapy. The BP reduction induced by the combination of these drugs during the dark phase was more marked than that during the light phase. 4. None of the drug therapies affected the HR and activity diurnal rhythms. 5. The results of the present study demonstrate that the telemetry method is useful for monitoring the antihypertensive effects of drugs in SHR under physiological conditions with minimal stress.

Alkaloids↗

soxRS gene increased the level of organic solvent tolerance in Escherichia coli.

Escherichia coli strain JA300 grows in the presence of n-hexane, but not in the presence of cyclohexane. We isolated a 10.5-kb DNA fragment that provided cyclohexane tolerance on a multi-copy plasmid, from the chromosomal DNA of JA300. In this fragment, there were found C-terminal 10-amino acids truncated soxR (soxR') and soxS which control the superoxide response regulon genes. Characterization of subclones found that both the soxR' and overexpression of the soxS increased the levels of organic solvent tolerance in several E. coli strains.

Cyclohexanes↗

Lung clearance of particles following excessive deposition of fly ash in golden hamsters.

Male golden hamsters were exposed to coal fly ash (FA) at the concentration of 0 (control), 1, 2, or 20 mg/m3 for 3 or 6 months (20 hr/day, 7 days/week). They were sacrificed at 0, 1, 3 and 6 months after exposure to undergo morphological investigation of the lung clearance of particles ingested by alveolar macrophages (AMs) following excessive deposition of FA particles. Particle-laden AMs in a cluster decreased in inverse proportion to the dust burden after the cessation of exposure. AMs with well-spread lamellipodia frequently appeared on the degenerated AMs in a cluster. In addition, neutrophils also agglomerated mainly in the alveoli proximal to the terminal bronchioles and ingested a small amount of particles. These results suggest that AMs and neutrophils might recruit into alveoli enclosing AMs in necrosis and reingest released particles. Macrophages in bronchioles generally ingested fewer particles than those clustered in alveoli. This finding suggests that AMs ingesting a small amount of released particles could move on the mucociliary escalator of the terminal bronchioles. On the other hand, AMs ingesting a large amount of particles would agglomerate in alveoli due to the loss of their migrating ability. The latter agglomeration of particle-laden AMs might be responsible for the retardation of lung clearance in proportion to the lung burden of particles.

Air Pollutants↗

[Study on prevention of flare-up phenomenon following initial LH-RH analogue administration: combination therapy with diethylstilbestrol].

To eliminate the initial testosterone (T) surge and prevent the risk of flare-up induced by the first administration of luteinizing hormone-releasing hormone (LH-RH) analogue, we examined the effectiveness of short-term combination therapy with diethylstilbestrol (DES). Sixteen previously untreated patients with prostate carcinoma (Stage C: 4 cases, Stage D2: 12 cases) were randomly assigned to 4 groups. Each group included 4 patients. Group 1 received DES (500 mg daily injection) for 7 days, staring before the first subcutaneous injection of luteinizing hormone releasing hormone (LH-RH) analogue (3.6 mg of Zoladex depot); Group 2 received 500 mg of DES injection for 7 days prior to the initiation of therapy with the LH-RH analogue, and moreover received a DES injection for 7 days; Group 3 received 500 mg of DES injection for 7 days simultaneously with the first injection of the LH-RH analogue; Group 4 was pretreated with 500 mg of DES injection for 7 days prior to the initiation of therapy with the LH-RH analogue, with additional DES injection for 3 days. In groups 1, 2 and 4 the level of T decreased during the 7 days of DES therapy, and at 3 days after the first injection of LH-RH analogue increased again. The mean T value in groups 1, 2 and 4 decreased by 33.2 +/- 27.6% (mean +/- SE), 20.5 +/- 20.8%, 13.2 +/- 9.8%, respectively, at the day of the first injection of LH-RH analogue, and increased by 75.2 +/- 21.6%, 70.7 +/- 63.4%, 56.7 +/- 46.4%, respectively, at 3 days after the first injection of LH-RH analogue.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗

[Study of medical economy in home parenteral nutrition].

UNLABELLED: The authors studied the relation between home parenteral nutrition (HPN) and medical economy. The items of study are 1) cost benefit of HPN compared with TPN, 2) hospital intention to promote HPN, 3) economical demerits for outpatients receiving HPN. RESULTS: 1) HPN had the advantage of cost benefit compared with TPN in reimbursement; however, hospitals did not have such an intention. 2) It is necessary for advanced home care to improve reimbursement in the health insurance system; and in the existing situation, hospitals do not profit from HPN. 3) Home care companies are unprofitable because of nursing visits and reimbursement issues which do not ease legal restrictions. 4) HPN in the present situation depends on the ability of patients to pay and the ability of care givers to provide care.

Cost-Benefit Analysis↗

Inhibitory activity of chlorophyllin on the genotoxicity of carcinogens in Drosophila.

Antimutagenic activity of copper chlorophyllin against various carcinogenic mutagens was assayed with Drosophila genotoxicity tests, i.e., the wing spot test for detecting somatic cell mutations and the DNA repair test for detecting DNA damage. In these tests, Drosophila larvae were fed carcinogens together with chlorophyllin. Polycyclic aromatic compounds, including heterocyclic amines, polycyclic aromatic hydrocarbons, aromatic amines and aromatic nitro compounds, were subject to inhibition, with a few exceptions. The results support the view that chlorophyllin traps carcinogens by forming complexes, thereby inhibiting the absorption of these compounds from the digestive tract. Consistent with this mechanism, Sepharose-supported chlorophyllin in the feed inhibited the Trp-P-2-induced wing spot formation, while Sepharose itself was ineffective.

Animals↗

Cloning of organic solvent tolerance gene ostA that determines n-hexane tolerance level in Escherichia coli.

A variety of genes are involved in determining the level of organic solvent tolerance of Escherichia coli K-12. Gene ostA is one of the genes contributing to the level of organic solvent tolerance. This gene was cloned from an n-hexane-tolerant strain of E. coli, JA300. A JA300-based n-hexane-sensitive strain, OST4251, was converted to the n-hexane-tolerant phenotype by transformation with DNA containing the ostA gene derived from JA300. Thus, the cloned ostA gene complemented the n-hexane-sensitive phenotype of OST4251.

Cloning, Molecular↗

Chlamydia trachomatis infection in the semen of asymptomatic infertile men: detection of the antigen by in situ hybridization.

The prevalence of Chlamydia trachomatis and other microbes was studied in 94 semen samples from asymptomatic infertile males. Simultaneously, we sought evidence for inflammation of the genital tract by determining the polymorphonuclear granulocyte (PMN)-elastase concentration in the seminal plasma. The C. trachomatis genome was detected in 8 cases using in situ hybridization. The antigen, however, was undetectable by enzyme-linked assay (Chlamydiazyme) in the same samples. Ureaplasma urealyticum was isolated from 16 cases. The PMN-elastase concentration in the semen positive for the C. trachomatis genome was significantly higher than in C. trachomatis-negative and U. urealyticum-positive cases, but no significant difference was observed between C. trachomatis-negative and U. urealyticum-positive cases. C. trachomatis trachomatis in situ hybridization-positive cases correlated well with C. trachomatis-specific IgA antibody positivity and a PMN-elastase concentration over 250 ng/ml. These findings suggest that in situ hybridization is a reliable method for the detection of C. trachomatis infection and that the presence of C. trachomatis, but not U. urealyticum, in the male genital tract correlated well with evidence of inflammation.

Adult↗

Early tensile bond strengths of several enamel and dentin bonding systems.

Tensile bond strength tests are commonly used for the evaluation of adhesive dental materials. The majority of these tests are carried out after 24 h of storage in water. However, determination of the early tensile bond strength could be more important, especially in relation to gap formation between the cavity surface and the restorative material. This study investigated the tensile bond strengths of five enamel/dentin bonding systems and two experimental dentin bonding systems. Tensile bond strengths were obtained at one min, ten min, and 24 h after the resin composite was cured. Bond strengths at the early stages were always somewhat less than the 24-hour test results. For the enamel/dentin bonding systems, a significant difference was found between the enamel and dentin bond strengths at all time periods, except with Superbond D-liner and Liner Bond. The experimental group with glyceryl methacrylate as the primer produced a good 24-hour result (14.3 MPa), but the early bond strengths were no different from those in the non-primer-treated groups. It was concluded that this material may actually retard the polymerization of the bonding resin. Previous workers have suggested that a tensile bond strength in the order of 20 MPa is necessary for gap-free restorations to be obtained. Should this be the case, then all of the materials tested, from the aspect of early bond strength, lack the strength for prevention of gap formation, although Superbond D-liner and Liner Bond approached this hypothetical figure. These systems, Superbond D-liner and Liner Bond, also exhibit small differences between the enamel and dentin tensile bond strengths.

Analysis of Variance↗

Mapping of organic solvent tolerance gene ostA in Escherichia coli K-12.

The extent of organic solvent tolerance was variable among strains of Escherichia coli K-12. Genetic analyses of n-hexane-tolerant strains indicated that a number of genes were involved in the solvent-tolerance phenotype. One such gene, designated ostA, was mapped at 1.2 min, close to pdxA. Transduction of ostA from a n-hexane-sensitive strain to a n-hexane-tolerant strain generated n-hexane-sensitive transductants. The sensitive transductant restored n-hexane-tolerance by transduction of ostA from a tolerant strain. Thus, the gene ostA is one of the genes that contributes to deciding the level of organic solvent tolerance in E. coli.

Conjugation, Genetic↗

Accumulation of alveolar macrophages induced by inhalation exposure of coal fly ash in golden hamster lungs.

To investigate the possible mechanisms of the accumulation of particle-laden alveolar macrophages (AMs) in alveoli, male golden hamsters were exposed to coal fly ash (FA) at the concentration of 0 or 2 mg/m3 for 6 months (20 hr/day, 7 days/week) in the first series of experiments, and at 0, 1, 2, or 20 mg/m3 of FA for 3 months in the subsequent experiments. Particle-laden AMs accumulated dose- and time-dependently in alveoli. In the lungs of 1 and 2 mg/m3-exposed groups. AMs first appeared in a cluster in alveoli at the alveolar-bronchiole junctions proximal to the lobar bronchus. Agglomerated AMs in these regions were generally larger in size and ingested more particles than those in the peripheral regions. These results indicate that the accumulation of AMs is closely related to the amount of particles deposited in alveoli and that ingested by AMs. Histochemical analysis revealed that AMs with small amount of particles showed the positive activity of acid phosphatase. On the other hand, heavily particle-laden AMs showed no such activity. Scanning electron microscopic observations revealed the time-related formation of small blebs and loss of surface features on the cell surface of AMs. These results suggest that the accumulation of particle-laden AMs might be caused by the decrease and/or loss of their activities, especially their mobility during migration toward terminal bronchioles from alveoli, due to the increase of ingested particles in parallel with the prolongation of exposure time.

Animals↗

[Significance of transrectal ultrasonography in surgery for stress urinary incontinence and cystocele. Assessment of the bladder neck suspension by measuring posterior urethrovesical angle and angle of inclination of the upper urethra].

We treated 42 females (26 with genuine stress urinary incontinence, 13 with incontinence and cystocele, and 3 with cystocele) with bladder neck suspension using transrectal ultrasonography during operation. The optimum tightness of suspension was decided by adjusting the posterior urethrovesical angle to about 90 degrees in 26 patients with genuine stress urinary incontinence accompanied with flattened posterior urethrovesical angles and by adjusting the angle of inclination of the upper urethra to about 10 degrees in 16 patients with cystocele accompanied with rotationally descended urethra. Urinary continence was achieved in 35 of 39 patients presenting with urinary incontinence. Three patients with cystocele without urinary incontinence remained dry after the operation. The average of maximum urinary flow rate significantly increased after operation. The angles of inclination of the upper urethra measured on the ultrasonogram during operation corresponded well with those measured on the post-operative lateral urethrocystogram. In 26 patients without cystocele, the angles of inclination of the upper urethra and the posterior urethrovesical angles were correlated significantly on the pre-operative urethrocystograms. Roentgenographic changes in pre- and post-operative urethrocystograms showed concomitant restoration in the angles of inclination of the upper urethra and in the posterior urethrovesical angles as well as significant elevation of the bladder neck. Present results indicate that the angles of inclination of the upper urethra measured by transrectal ultrasonography during operation as well as the posterior urethrovesical angles are useful and reliable to decide the optimum tightness of bladder neck suspension for the patients with stress urinary incontinence accompanied with rotationally descended urethra.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Experience of ileal neobladder for bladder cancer by Hautmann procedure].

Operative results of ileal neobladder by the Hautmann procedure were studied in the patients with bladder cancer. From 1990 to 1993, 23 patients underwent total cystoprostatectomy for transitional cell carcinomas of the bladder. In 12 of these patients, an ileal neobladder was constructed for total bladder replacement under the following criteria; patients 1) with cancer confined in the bladder (T3b, M0, N0 or less), 20 without carcinoma in situ extending to more than half of urothelium of the bladder, 3) without cancerous lesion in the bladder neck or the prostatic urethra, 4) with performance status of 0 and the age of 75 or less. Pathologically, the disease was grade 2 in 3 patients, grade 3 in 9, stage pT1b in 3, stage pT2 in 4, stage pT3a in 1 and stage pT3b in 4. Two of 3 patients with the disease of stage pT1b had multiple papillary tumors. The remaining one patient had microinvasive cancer that carcinoma in situ infiltrated into submucosal area. Radical cystoprostatectomy and total bladder replacement by Hautmann procedure was performed in all patients. The maximum neobladder capacity was 349.5 +/- 58.1 ml (mean +/- SD). The intravesical pressure at maximum capacity was 30.6 +/- 6.2 cmH2O. At half maximum capacity, the intravesical pressure was 17.1 +/- 6.8 cmH2O. the maximum urethral closure pressure and the functional urethral length were 89.2 +/- 38.1 cmH2O and 25.5 +/- 7.0 mm, respectively. One patient had stress urinary incontinence. Slight nocturnal incontinence was found in 2 patients and nocturia was 1.86 +/- 0.55 times.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[Analysis of continence mechanisms by stress urethral pressure profiles].

The urethral pressure profiles (UPP) at rest and under stress, using double lumens microtip transducer catheter, in 17 females without urinary incontinence (normal group) were compared with those in 39 females with stress urinary incontinence (SUI group). And UPP were compared pre- and postoperatively in 21 females of SUI group who had surgical cure of SUI by bladder neck suspension (operative group). Pressure transmission ratios (PTR) were calculated in each quartile dividing functional urethral length (FUL) into four equal lengths. Maximum urethral closure pressure (MUCP) and Functional urethral length (FUL) in normal group were significantly higher than those in SUI group. In normal group, although bladder neck opening under stress (bladder neck incompetence) existed in 41% of them, the PTR in the distal three-quarters of the FUL were significantly larger than those in SUI group and urinary continence was remained in all of them. On the contrary, in SUI group, there was an almost linear decrease in the value of the PTR along the FUL. Therefore, it was suggested that SUI patients might lose distal urethral compensatory mechanisms. The results, obtained from the resting UPP, show that there is no significant change in MUCP or FUL following bladder neck suspension. In contrast, the stress UPP shows that successful operation generated a magnification of the PTR in the proximal three-quarters of the FUL. Only 1 case of post operative group showed bladder neck incompetence. Therefore suspending the bladder neck in a high position might produce the ability to occlude proximal three-quarters of the FUL.

Adult↗

[Inverted Y ureteral duplication with a ureteral stone in atretic segment: a case report].

A 46-year-old male was admitted with the chief complaint of right side abdominal pain. A retrograde urogram disclosed right hydronephrosis and an anomalous branch in the shape of an inverted Y accompanied by a calculus on the right ureter. Extirpation of the calculus and vesicoureteroneostomy were performed just above the bifurcation. The anomalous branch was blind-ending.

Anastomosis, Surgical↗

[Effect of lentinan for advanced prostate carcinoma].

A prospective, randomized multi-center study was conducted to assess the clinical effectiveness of Lentinan, an immunomodulatory agent, in the metastatic prostate cancer. Of seventy-five patients enrolled from July 1987 to June 1992, 69 were eligible. All patients received hormonal therapy and chemotherapy using Tegafur p.o. at a dose of 400-800 mg/day. While 33 patients received Lentinan i.m. for at least three months, the other 36 did not. The dose of Lentinan was 2 mg weekly for inpatients and 4 mg every other week for outpatients. The mean age of treated and control patients was 70 (range; 53-83) and 71 (range; 50-86), respectively. The 50% survival length of treated and control patients was 48 and 35 months, respectively. The five-year survival rate of treated patients was 43% according to the Kaplan-Meier method, while that of control patients was 29% (p < 0.05). We conclude that Lentinan is effective in metastatic prostate cancer when incorporated into hormonochemotherapy.

Aged↗