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T Harada

Publications and source records attributed to T Harada.

At least 829 records · Page 46Linked to original sources
PubMed1988

Three-dimensional reconstruction of the temporal bone from histologic sections.

To increase understanding of the stereoscopic anatomy of the temporal bone, we have developed a computer system for three-dimensional reconstruction of the temporal bone from human histologic sections. The results were satisfactory for reconstructing details of complicated temporal bone structures. This system is equipped with such functions that it is possible to observe the reconstructed structures from an arbitrary direction, and to investigate their internal aspects by cutting and drilling. Three-dimensional reconstruction by this method is useful not only in understanding the fundamental anatomy and stereoscopic relationship of various parts of the temporal bone, but also in simulating temporal bone surgery on reconstructed three-dimensional images.

Humans↗
PubMed1988

Blood pressure in Japanese children during the first three years of life. The Hisayama Study.

Blood pressure (BP) measurements were obtained from 522 healthy young children aged from 3 months to 3 years in Hisayama, Japan. The measurements were performed using a Doppler ultrasound device applied to children who were awake and sitting quietly on their mothers' laps. This method of obtaining BP was successful in 80% to 90% of children aged 3, 6, and 36 months, and in 60% to 70% of children aged between 12 and 18 months. Mean systolic BP varied from 88 mm Hg at 3 months to 96 mm Hg at 3 years and showed a tendency to elevate with increasing age, with the increment being the greatest between ages 3 and 6 months. Mean diastolic BP was constant throughout the first three years of life.

Aging↗
PubMed1988

Three cases with light-induced retinopathy.

Three patients presented a characteristic retinopathy presumably induced by light arising from operating microscope during extracapsular cataract extraction combined with intraocular lens insertion. The operating microscope was equipped with video-recorder. Light sources were tungsten bulb. All cases were asymptomatic and an inspection at the post-operative control examination led to the detection of this type of retinopathy.

Aged↗
PubMed1988

The effects of an intracellular calcium antagonist HA 1077 on delayed cerebral vasospasm in dogs.

The effectiveness of calcium antagonists on a chronic cerebral vasospasm after an SAH is still under debate. Calcium channel blockers such as nimodipine, nifedipine etc. can dilate spastic arteries by intrathecal administration, but not by systemic (iv or po) use. HA 1077 is a novel and potent calcium antagonist vasodilator which is considered to act by employing different mechanisms from the usual calcium channel blockers since it inhibits 1. calcium ionophore A 23187 induced contraction in arterial strips and 2. phenylephrine induced contraction in calcium free media, suggesting that its site of action is in the intracellular space. HA 1077 is water soluble and relatively stable in light. In the present study, the efficacy of HA 1077 was evaluated on dogs by using the spiral arterial strips in vitro and by angiography in vivo. In the arterial strips from the control dogs, a 50% relaxation of KCl (15 mM) induced contraction was obtained by a 10(-6) M HA 1077 for the "intracranial" basilar and middle cerebral arteries, while a 10(-5) M was needed to obtain the same effect for the "extracranial" common carotid and vertebral arteries, indicating that HA 1077 is more effective for the intracranial arteries. A vasospasm was produced by the "two haemorrhage" model of Varsos et al. The average angiographic diameter of the basilar artery was reduced to 60% of the control on SAH day 7. Intravenous infusion of HA 1077 (0.5-3 mg/kg/30 min) significantly dilated the spastic basilar artery (up to 20-30%), for over 2 hours. A fall in the systemic BP remained less than 20% during this time.(ABSTRACT TRUNCATED AT 250 WORDS)

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1988

In vivo selection of tumorigenic subline from non-tumorigenic human gastric carcinoma cells: in relation to proliferative properties in vivo and in nude mice.

Human gastric carcinoma cells from one of three long-term cultured cell lines (HPE-GAC-T) were injected into peritoneal cavities of BALB/c mice. The surviving celss in vivo were collected 3 days later. Following brief cultivation in vitro, those cells were reinjected into mice by the same route. This procedure was repeated 3 times. The cultured cancer cells recovered from the mice on the 3rd passage, at a 92.5% recovery rate, showed xenotransplantability in BALB/C nu/nu mice by subcutaneous injection. This subline (GAC-T.M-2) can be maintained in vitro but not in vivo while maintaining heterotransplantability. Three original cancer cell lines did not show tumorigenicity in nude mice. Animal passages by the same protocol failed to select tumorigenic sublines from the other cell lines (HPE-GAC-2 and -3). Factors affecting tumorigenic capacity of cancer cells in nude mice were studied in vivo and in vitro by comparing the properties of GAC-T.M-2 and parental cancer cells (GAC-T.O). Treatment of the hosts by injection of anti-asialoGM1 antibody or cyclophosphamide, adult thymectomy of BALB/c mice, and 400 rads whole body irradiation did not enhance the growth of either GAC-T.M-2 or -T.O cells. There was no detectable difference between in vitro growth properties of the original and variant cells at a rather high cell density. However, at a low cell density GAC-T.M-2 cells showed a higher cell growth rate and increased [3H] thymidine incorporation and possessed higher colony forming activity in the liquid medium than their parental cells. High dense expression of epidermal growth factor (EGF) receptors was evident equally in both GAC-T cells, however, GAC-T.M-2 cells were more sensitive to down-regulation by EGF in culture. Tumor cells of HPE-GAC-2 and -3 lines expressed minimum amount of EGF receptors on their cell surfaces and were refractory to additional EGF in culture. The results indicate that growth factors and their receptors are responsible for tumorigenicity in nude mice.

Animals↗
PubMed1988

Liver cell carcinomas in the medaka (Oryzias latipes) induced by methylazoxymethanol-acetate.

Medaka (Oryzias latipes) were treated with 0.3 ppm methylazoxymethanol-acetate (MAM-A) for 3 days (group I) and with 0.1 ppm MAM-A for 2 weeks (group II) and the effects on the medaka liver cells up to 6 weeks after commencement of the treatment and the induction of liver tumours at the 18th or 24th weeks were observed by light and electron microscopy. As an early effect, PAS-positive granules and basophilic liver cells appeared at the fourth or fifth week in group II. In group I, PAS-positive granules, basophilic liver cells and eosinophilic liver cells were observed from the second week. They tended to increase in number and formed aggregate bodies and basophilic liver cell foci. The aggregate bodies of PAS-positive granules resembled melano-macrophage centres (MMC). However, there were ultrastructural differences between these aggregate bodies and MMC. Basophilic liver cells contained much rough-surfaced endoplasmic reticulum and eosinophilic liver cells contained much smooth-surfaced endoplasmic retriculum and mitochondria by electron microscopical observation. Liver cell nodules appeared in 3 out of 21 fish but liver tumours were not found within 24 weeks in group II. In group I, basophilic liver cell foci progressed to liver cell nodules in 5 out of 9 fish. Furthermore, they progressed to liver cell adenomas in 3 and carcinomas in 3 of 9 fish at 18 weeks. The sequential morphological alterations observed in the present experiment were similar to those obtained in rats. Basophilic liver cell foci appeared to be an early aspect of hepatocarcinogenesis in medaka. Considering the susceptibility of medaka to the carcinogenic effect of MAM-A in a relatively short time and the low concentration of this material required for induction of tumours, medaka seems to be a useful animal for research on neoplasms and pre-screening carcinogenicity of chemicals.

Animals↗
PubMed1988

Bactericidal activity of middle ear effusion on a single isolate of non-typable Haemophilus influenzae.

Bactericidal activity of middle ear effusion (MEE) from children with otitis media with effusion (OME) on one strain of non-typable Haemophilus influenzae was measured and was compared with that of normal human serum. H. influenzae culture negative MEEs had a bactericidal activity on one strain of non-typable H. influenzae (P less than 0.01), and the activity of serous effusions was significantly stronger than that of mucoid ones (P less than 0.01). The bactericidal activity of 20% pooled MEE was almost equal to that of 4% normal human serum. Heat treatment (56 degrees C, 30 min) abolished this activity of both pooled MEE and normal human serum. Addition of fresh guinea pig serum (GPS) as a complement source to the heat-treated pooled MEE restored this activity, while its addition to the heat-treated normal human serum failed to do so. These results suggest that complement factor is important in the bactericidal activity of MEE.

Adolescent↗
PubMed1988

Pontine micturition center in the dog.

The function and location of the pontine micturition center was studied in ten decerebrate dogs by physiological experiments in which micturition induced by electrical stimulation of the pontine micturition center was compared with reflex micturition in response to bladder filling with physiological saline and by histological studies of the electrolytic lesions made at the stimulated areas. The micturition induced by electrical stimulation of the pontine micturition center showed the same pattern of detrusor contraction, simultaneous urethral relaxation and the elevation of the tail as reflex micturition in response to bladder filling. The peak contraction pressures in both micturitions showed no obvious differences. The electrolytic lesions were histologically identified at the locus coeruleus alpha in six out of 10 dogs, at the locus coeruleus in three and at the peri locus coeruleus alpha in one dog. The coordinated activities of bladder and urethra in the micturition induced by electrical stimulation of locus coeruleus or its subparts suggest that these areas perform an important role in the urine emptying function.

Animals↗
PubMed1988

Squamous cell carcinoma antigen in the serum of oromaxillary cancer.

Squamous cell carcinoma (SCC) antigen levels in sera and several tissues were estimated in patients with oral and maxillary cancer. The normal value of serum SCC antigen level was 1.7 ng/ml in this experiment, and 43.3% of squamous cell carcinoma was positively higher than 1.7 ng/ml as a whole, including cases of carcinoma in situ and of recurrence and metastasis in the oral region. In relation to the clinical staging of tumors, 20.0% in stage I, 14.3% in stage II, 42.9% in stage III, and 77.8% in stage IV were positive for SCC antigen. In the group with definite regional lymph node metastases, 80% of patients revealed a higher value than the normal cut-off value. Patients with recurrent SCC demonstrated elevated SCC antigen values in sera except 1 case with an early condition of recurrence. Serum SCC antigen also presented good responses to various cancer treatments. The measurement of SCC antigen does not appear to be useful for the detection of early stage oral and maxillary SCC; however, for detection of recurrence and for lymphatic and/or remote metastases in the follow-up period, it would appear that SCC antigen level would be some value.

Adult↗
PubMed1988

Effect of human epidermal growth factor on cell growth and its receptor in human gastric carcinoma cell lines.

The effect of human epidermal growth factor (hEGF) on the growth of various histological types of six human gastric carcinoma cell lines was examined. The cell lines had relatively high affinity EGF receptors (dissociation constant Kd = 10(-9) to 10(-10) M). One gastric cancer cell line, MKN-74 (well differentiated adenocarcinoma) showed no response to hEGF, in cell growth, DNA synthesis or 125I-hEGF cell binding. There were no apparent correlations between histological type and cell growth, DNA synthesis or number of EGF receptors in these cells. The number of EGF receptors and the Kd value of the gastric carcinoma cell lines varied with their internal and external environments. hEGF concentrations corresponding to maximum stimulation in DNA synthesis varied between cell lines. The results suggest some gastric carcinoma cells to have EGF receptors and their growth seemingly to be stimulated by EGF in vitro. There are, however, no obvious correlations between the effect of hEGF on the growth of human gastric carcinoma cell lines or their histological type.

Adenocarcinoma↗
PubMed1988

Characterization and partial purification of a non-interferon macrophage activating factor produced by human leukemic T cell line.

Culture supernatants from several human leukemic T cell lines were found to contain a macrophage activating factor which enhanced hydrogen peroxide release from human peripheral blood monocyte-derived macrophages. The macrophage activating factor from a T cell line, CCRF-CEM, was characterized biochemically and compared with interferon-gamma, which is also an immunological product of T cells and has a potent macrophage activating activity. In contrast to interferon-gamma, the macrophage activating factor in the culture supernatants bound to an anion exchanger and did not adsorb onto concanavalin A gel. Culture supernatants and active fractions from chromatographies were essentially devoid of anti-viral activity. Anti-human interferon-gamma monoclonal antibody also failed to neutralize the macrophage activating factor from CCRF-CEM. MAF was eluted in the fractions with molecular weight of 40,000 to 60,000 on gel filtration in the presence of a detergent and a salt. MAF was partially purified to about 1,300-fold by the methods described above: chromatography with anion exchangers and gel filtration. It was concluded that MAF from CCRF-CEM was biochemically and immunologically different from interferon-gamma.

Chromatography, Ion Exchange↗
PubMed1988

Fine structure of melanocytes and macrophages in the Harderian gland of the mouse.

The presence of dendritic cells containing melanin granules has been demonstrated employing silver impregnation and electron microscopy in the interstitial tissue of the Harderian gland of the mouse. Two types of melanocytes, either with or without the various developmental stages of melanin granules, were found in the gland. Cells with developing granules were more dendritic and contained a large number of cytoplasmic organelles. The other cells were ellipsoidal or slender in shape and contained few cytoplasmic organelles and a large number of fully melanized granules, but no developing granules. In general, the granules of the Harderian gland melanocytes resembled granules from other organs (particularly the skin of the eyelids). The general size range of the granules was 0.2-0.9 micron. Each granule was enclosed by a membrane. The Harderian gland macrophages contained fully pigmented melanin granules of various sizes. The granules were enclosed by a membrane either singly or in groups. Some of the melanin granules within the phagosomes showed signs of degradation, revealing the underlying matrix.

Animals↗
PubMed1988

Viral infection and the inner ear.

The work of Japanese research committees on the relation of viral infection to sudden deafness and acute profound deafness is briefly introduced. The criteria for making a diagnosis of sudden deafness and mumps deafness are described. A new method of detecting IgM antibody to mumps virus was developed in research done for one of the committees. Use of this method revealed that sudden deafness in 1 out of 39 patients was due to mumps virus. Experimental viral labyrinthitis was produced in guinea pigs using herpes simplex virus (types 1 and 2) and guinea pig cytomegalovirus (GPCMV). Histopathological studies were conducted, and the results are discussed and compared with those for human viral labyrinthitis. Anomaly of the cochlea was found in the offspring of a guinea pig which became pregnant just after GPCMV was inoculated into its cochlea.

Animals↗
PubMed1988

Combination therapy with microwave coagulation and intracavitary irradiation for bladder cancer. Technique and preliminary clinical results.

Twenty-five patients with transitional cell carcinoma of the bladder have been treated with combined therapy consisting of microwave regional coagulation and intracavitary irradiation. A remote-controlled after-loading system was utilized for the radiation therapy. The follow-up period ranged from 6 to 19 months with an average of 11.4 months. Tumor stages were Tis (n = 2), Ta or T1 (n = 17), T2 (n = 2), T3 (n = 3) and T4 (n = 1), and grades were G1 (n = 10), G2 (n = 11) and G3 (n = 4). In 23 patients (92%), there was no endoscopic or histologic evidence of tumor after the initial treatment. Heterotopic recurrences were found after 2 or 3 months in 3 patients who received microwave regional coagulation or intracavitary regional irradiation. Additional intracavitary whole bladder mucosal irradiation was performed for 10 patients with multiple tumors and frequent recurrent tumors. Nine patients had no recurrence (average follow-up 11 months). Our preliminary findings indicate that combination therapy of microwave coagulation and intracavitary irradiation is a useful treatment for bladder cancer.

Brachytherapy↗
PubMed1988

Microwave coagulation therapy for urinary bladder tumors.

A new device has been developed for microwave coagulation of urinary bladder tumors. Twenty-one patients with urinary bladder tumors were treated by irradiation with microwave energy of 2,450 MHz. Results were obtained as follows: (1) microwave coagulation was performed in 21 patients with transitional cell carcinoma of the urinary bladder. Excluding 4 patients who subsequently received radical cystectomy, 17 patients showed a complete response, although 2 patients subsequently developed recurrences in different parts of the bladder within the following several months. Histological examination of the excised specimen revealed complete eradication of the tumor in 2 patients. In the remaining 2 patients with high-stage tumor (T4), viable tumor cells were noted in the urethra or vaginal wall. (2) Although neither technical difficulties nor severe complications were encountered, transient urinary frequency and calcification of the bladder wall were noted. The results of this study indicate that microwave coagulation may be used in the treatment of both superficial and invasive tumors.

Aged↗
PubMed1988

Mortality, major cause of moribundity, and spontaneous tumors in CD-1 mice.

Mortality, major causes of moribundity, and spontaneous tumors in CD-1 mice were studied in 891 males and 890 females, which were used as controls in 11 different 2-year chronic and oncogenicity studies during the past 5 years. Average mortality of males and females at 83 weeks of age was 32.6% and 28.6%, respectively, and at 109 weeks of age was 66.4% and 63.3%, respectively. Mortality was significantly lowered in males and females born after 1980 in accordance with an abruptly decreased occurrence of systemic amyloidosis in these animals. The major cause of death or moribundity included systemic arteritis, systemic amyloidosis, auricular thrombosis, glomerulosclerosis, lymphoma, and pulmonary adenocarcinoma in both sexes. Dysuria and hepatocellular carcinoma in males and mammary adenocarcinoma in females were also critical lesions. The major tumors occurring at more than 3% incidence were systemic lymphoma, adenoma/adenocarcinoma of the lung, adenoma/carcinoma of the liver and adenoma/adenocarcinoma of the Harderian gland for males, and systemic lymphoma, adenoma/adenocarcinoma of the lung, adenoma/carcinoma of the liver, leiomyoma/leiomyosarcoma of the uterus, adenoma/adenocarcinoma of the pituitary (anterior), adenoma/adenocarcinoma of the mammary gland and adenoma/adenocarcinoma of the Harderian gland for females. Intralaboratory heterogeneities in the incidence were recorded as follows: systemic lymphoma in 1 of 11 control groups (1/11) and adenoma/adenocarcinoma in 1/11 for males, and systemic lymphoma in 3/11, adenoma/adenocarcinoma of the lung in 2/11, adenoma/adenocarcinoma of the liver in 1/11, and adenoma/adenocarcinoma in 1/11 for females.

Amyloidosis↗