Search PubMed⌕ Search

Biomedical subjects

K Hamada

Publications and source records attributed to K Hamada.

At least 415 records · Page 23Linked to original sources
PubMed1989

[Arthrography of recurrent dislocation of the TMJ--with special reference to the movement of the articular disk].

To investigate the movement of the articular disk in recurrent luxations, 4 temporomandibular joints in three patients were studied with the arthrotomographs. All the superior articular cavities were extended anteriorly. On the mouth open in two patients with recurrent subluxation, the mandibular head accompanied with the articular disk located very anterior position from the articular tubercle. At this time, the retro-discal pad were stretched, but the relation between mandibular head and articular disk were normal findings: the mandibular head located on the central thin part of the articular disk. One of them showed anterior disk displacement with reduction. The other patient showed the bone cavity at the anterior slope of the articular tubercle. On the mouth open, the mandibular head and posterior band fitted that cavity. The other hand, remaining one patient was recurrent luxation on the left side. On the mouth open, the relation between mandibular head and articular disk were abnormal findings: The mandibular head located very anterior position, over the articular tubercle and anterior band of the disk. Therefore, the inferior articular cavity was extended, but the retro-discal pad was not stretched. The anterior slope of the articular tubercle was steep. The other side TMJ of this patient was recurrent subluxation and anterior disk displacement with reduction. On the mouth open, it was showed the hypermobility of mandibular head. But the relation between mandibular head and articular disk were normal findings. As mentioned above, in luxation and subluxation, it was made obvious that there were tow types about the relation between mandibular head and articular disk on the mouth open: one type was that mandibular head located anteriorly to the anterior band of the disk, the other was under the disk.

Arthrography↗
PubMed1989

Examination of the inhibitory effects of interferon-gamma on interleukin-4-induced stimulation of resting B cells from NZB/NZW F1 mice.

Percoll fractionation of NZB/NZW F1 mouse B cells revealed an increased ratio of low-density fraction ('activated' B cell fraction) and a decreased ratio of high-density fraction ('resting' B cell fraction), in comparison to normal mouse B cells. Resting B cells of B/W F1 mice were hyperresponsive to interleukin-4 (IL-4), with increased proliferation and IgG anti-DNA antibody production, in comparison to normal mice. The hyper-responses of resting B cells from NZB/NZW F1 mice to IL-4 were affected with dose dependency by interferon-gamma (INF-gamma); specifically, cell proliferation and anti-nuclear antibody production were suppressed in the presence of IFN-gamma. This suppressor action of IFN-gamma was most noticeable when it was added to the culture system simultaneously with IL-4. These findings suggested that the abnormally activated state of NZB/NZW F1 mice B cells can be attenuated by the action of IFN-gamma on resting B cells.

Animals↗
PubMed1989

[Qualitative and quantitative changes of luteinizing hormone (LH) in the pituitary glands in female Japanese monkeys (Macaca fuscata) during the menstrual cycle and after castration].

The present study was designed to investigate qualitative and quantitative changes in luteinizing hormone (LH) in the pituitary glands of female Japanese monkeys (Macaca fuscata) during the menstrual cycle and after castration. The pituitary glands were removed from 10 intact cycling Japanese monkeys and 3 castrated ones: The former sacrificed in the early, late follicular phase, and mid luteal phase, and the latter 8 weeks after castration. All 13 pituitary glands were fractionated by isoelectrofocusing (IEF). The mid cycle peaks of estradiol (E2) and bioactive LH occurred simultaneously in 11 out of 13 monkeys. No animals showed luteal phase peaks in the plasma E2 concentration. Bioactive LH content (IU/mg wet weight) in the pituitary gland was significantly correlated with plasma E2 levels in the cycling monkeys (R2 = 0.974) and it was the highest in monkeys in the late follicular phase. Bioactive LH in the pituitary gland was separated into 6 distinct species in terms of pI values by IEF; A(9.31 +/- 0.19), B(8.88 +/- 0.17), C(8.36 +/- 0.17), D(7.92 +/- 0.18), E(7.32 +/- 0.16) and F(acidic LH). Among alkaline LH species, the most predominant ones were Fractions B, C and D in the early follicular phase, Fraction A followed by B in the late follicular phase and Fraction B followed by C in the mid luteal phase. The neutral and acidic LH (Fraction E and F) was increased more in the early follicular phase and in the castrates. In conclusion, LH species separated by IEF may correspond to the stage of molecular maturation of pituitary LH.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[Clinical study of aminoglycosides on renal dysfunction--pharmacokinetics of arbekacin and its elimination effects by hemodialysis and adsorption with charcoal].

In vitro studies of elimination of arbekacin (HBK), a new aminoglycoside antibiotic, from blood by means of hemodialysis or adsorption with charcoal, and pharmacokinetic studies in patients with renal dysfunction were examined. HBK was well eliminated by hollow fiber type artificial kidney (HFAK) with a half-life of 0.13 hr. HBK was also well eliminated by an adsorption tube containing charcoal with even shorter half-life of 0.03 hr. As to pharmacokinetics of HBK in patients with renal dysfunction, blood levels became higher with a greater reduction in 24 hr endogenous creatinine clearance (Ccr). A decreasing tendency was also seen in urinary recovery rate. These results indicated that hemodialysis and adsorption with charcoal are useful for elimination of HBK from blood. It is recommendable in patients with renal dysfunction to take some measures such as prolongation of administration interval of HBK according to the extent of decrease in Ccr.

Adsorption↗
PubMed1988

[Technical study for SPECT of the head using slant hole collimator].

The performance of a 160 keV slant hole collimator (160 keV SH) was compared with that of a 140 keV high resolution collimator (140 keV HR) for SPECT imaging of the head using 99mTc. The minimum radius of revolution was reduced from about 23 cm to 13 cm using 160 keV SH. Relative sensitivity of the 160 keV SH was 108% of that of the 140 keV HR. Compared with SPECT using 140 keV HR, 160 keV SH SPECT yielded approximately a 15% increase in resolution. The 160 keV SH SPECT images of phantom were superior in resolution and contrast to that of 140 keV HR SPECT. We concluded that high quality SPECT images of the head can be obtained from rotating gamma cameras equipped with slant hole collimators.

Head↗
PubMed1988

[Fundamental study of the influence of pixel size on the quality of scintigrams].

The effect of pixel size on image quality was investigated. The image quality was examined by abnormality detection and image preference for clinical images displayed with different pixel sizes. Smaller pixel size was found to be superior to large one in image quality using large field of gamma camera (FWHM 6.42 mm), 1.6mm pixel size (a 256 x 256 matrix) was found to be the best in image quality. Examined image minification effect, 3.2 mm pixel size (image size: 5 cm phi) was found to be superior to 1.6 mm pixel size (image size: 10 cm phi) in image preference and to be almost equal to 1.6 pixel size in abnormality detection.

Bone and Bones↗
PubMed1988

[A case of giant vesical calculus after ileocystostomy].

A 52-year-old female, who had undergone nephrectomy and ileocystostomy for right-renal tuberculosis and contracted bladder 19 years earlier was seen with anemia and metabolic acidosis. Radiographic findings demonstrated that the patient suffered from a giant vesical calculus. Cystolithotomy was performed and the removed calculus weighed 460 g. Of the 66 cases of giant vesical calculus weighing more than 200 g reported in our country only 7 were in females.

Anastomosis, Surgical↗
PubMed1988

[Bilateral asynchronous renal pelvic tumors: a case report].

A 42-year-old male who had undergone the total nephroureterectomy for transitional cell carcinoma (Grade 3) in the left renal pelvis 5 years ago was seen with asymptomatic macroscopic hematuria. An evaluation of the clinical investigations revealed the right renal pelvic tumor. The right nephroureterectomy was performed and histological examination showed transitional cell carcinoma (Grade 2) of the renal pelvis. Postoperatively, the patient has been treated with intermittent maintenance hemodialysis. He is well and has no evidence of recurrence or metastasis 10 months after the surgery. The previous reports of bilateral renal pelvic tumors (28 cases) are reviewed and the incidence, age, interval between the first and second tumors, prognosis and management including postoperative hemodialysis are discussed.

Adult↗
PubMed1988

[Congenital anterior urethral diverticulum: report of a case].

A case of congenital urethral diverticulum is reported. A 6-month-old male was admitted with difficulty to urinate and swelling of the base of penile shaft. Anterior urethral diverticulum was demonstrated by means of retrograde urethrography. A diverticulectomy combined with cystostomy was performed under the general anesthesia. Although the histological findings were insufficient to determine whether the urethral diverticulum was congenital or acquired, the former was strongly suspected judging from his clinical course. He developed urethrocutaneous fistula, one of the most common postoperative complication, on the 7th post-operative day. A complete cure of the fistula was achieved by the conservative treatment. We collected and analyzed 49 cases of congenital anterior urethral diverticulum of male children in Japan.

Diverticulum↗
PubMed1988

[Adult neuroblastoma of the adrenal with intraatrial tumor thrombus: report of a case].

A case of adult neuroblastoma of the right adrenal with tumor thrombus extending into the right atrium is reported. Because of right heart failure, the tumor thrombus in the right atrium was removed under the cardiopulmonary bypass. The histopathological examination of the tumor thrombus revealed neuroblastoma. Fourteen days after the first operation, the adrenal tumor, right kidney and tumor thrombus remaining in the vena cava were removed to prevent the recurrence of right heart failure. Two courses of chemotherapy and radiation were given postoperatively and the patient was doing well. Eight months after the second operation, however, the patient died of multiple metastases of the bone and liver.

Adrenal Gland Neoplasms↗
PubMed1988

[Preclinical evaluation of a new anthracycline derivative, SM-5887 by subrenal capsule assay].

SM-5887, a new totally synthetic anthracycline derivative was evaluated the antitumor activity by subrenal capsule assay (SRCA) and the activity was compared to that of doxorubicin. The method of SRCA was the same originally developed by Bogden et al and 200 mg/kg of bredinin was administered subcutaneously 3 times every 2 days in order to induce immunosuppression of mice. Mice were given a single intravenous dose of either 30 mg/kg of SM-5887 or 15 mg/kg of doxorubicin. Fourty-four cases out of 64 were evaluable in this assay. The mean tumor growth inhibition rate (TGIR) in either SM-5887 or doxorubicin group was similar and the TGIRs of these two groups correlated well (y = 10.4 + 0.67x, p less than 0.01). Using more than 50% decrease of TGIR to define "sensitive", the chemosensitivity rates of SM-5887 and doxorubicin were 23% (10/44) and 25% (11/44) respectively. SM-5887 was effective to sarcomas and ovarian cancer especially. These results suggest that SM-5887 might have a similar antitumor activity compared to doxorubicin in clinical use.

Anthracyclines↗