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Biomedical subjects

H Okano

Publications and source records attributed to H Okano.

At least 181 records · Page 10Linked to original sources
PubMed1994

Cellular kinetics and lectin distribution in hamster buccal carcinomas.

As part of an evaluation of the progression to malignancy, the cellular kinetics of DMBA-induced tumors in the buccal mucosa of hamsters were examined using 5-bromodeoxyuridine (BrdU), peanut agglutinin (PNA), Ulex europaeus agglutinin I (UEA-I) and wheat germ agglutinin (WGA). BrdU-positive cells were localized in the basal layer in both normal and hyperplastic epithelium, whereas they were distributed from the basal to the prickle cell layer in squamous cell carcinoma (SCC). The extent of BrdU labeling increased as the tissues progressed towards malignancy. PNA and UEA-I showed binding only in the prickle cell layer of normal and hyperplastic epithelium, and WGA showed binding mainly in the prickle cell layer. However, in SCC, PNA and UEA-I showed no binding in the prickle cell layer and WGA binding was observed throughout the epithelium. A study of cellular kinetics using BrdU labeling and the lectin binding pattern may be useful in the evaluation of tissue changes on the way to malignancy.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1994

Physical exercise increases bone mineral density in postmenopausal women.

To examine whether physical exercise is beneficial in preventing postmenopausal osteoporosis, we measured bone mineral density (BMD) in three distinct groups of healthy postmenopausal Japanese women aged 49-61 yrs: 11 volleyball players (V) and 5 joggers (J), and 9 controls (C) who had not been participating in regular physical activity. BMD was measured at the lumbar spine (L2-L4) and proximal femur using dual energy X-ray absorptiometry, and at the radius using single X-ray photon absorptiometry. Serum levels of estradiol (E2), parathyroid hormone (PTH) and calcitonin were also measured by radioimmunoassay. Osteocalcin was determined by enzyme immunoassay. BMD in the lumbar spine was greater in the V and J groups than in the C group (P < 0.01). The J group had a significantly lower PTH level than the C group. In contrast to weight-bearing bones, we found no significant differences in BMD at the radius among the three groups. BMD at the distal radius was negatively correlated with years after menopause in both the V group and the J group significantly. These results indicate that regular physical exercise has a positive effect on the maintenance of bone mineral in postmenopausal women and that the protective action is localized in skeletal sites used predominantly for the sport without opposing the negative regulation caused by estrogen deficiency in systemic bones.

Aged↗
PubMed1994

Rare case with metastatic involvement of hypothalamo-pituitary and pineal body presenting as hypopituitarism and diabetes insipidus.

An unusual case with metastatic spread of a small oat cell lung carcinoma to the hypothalamo-pituitary region and pineal body presenting as pituitary insufficiency is reported. Computed tomographic scan revealed an isodense mass in the hypothalamo-pituitary region and pineal body that was strongly enhanced by contrast medium. Magnetic resonance imaging demonstrated a downward displacement of the posterior lobe of the pituitary by the hypothalamo-pituitary mass. Dynamic assessment of hypothalamo-pituitary function showed hypopituitarism and diabetes insipidus; partial recovery was observed with the improvement in the carcinoma by chemotherapy. The brain was subsequently irradiated. The patient survived 10 months.

Aged↗
PubMed1994

[A case of Castleman's disease that recurred nine years after initial surgical removal].

Castleman's disease (CD) is a lymphoproliferative disorder with resemblance in histopathology of thymoma. Here we describe a 48-year-old man with bloody sputum and a mass lesion of the right hilum on chest roentgenogram. He had undergone an incomplete surgical removal of a mediastinal tumor nine years earlier, which proved to be CD with characteristics of hyaline-vascular type pathology. The regrown mass lesion as well as the right upper and middle lobes were removed surgically. Histological examination of the tumor specimen revealed characteristics of hyaline-vascular type CD which were nearly identical to those of the tumor removed nine years earlier. Recurrence of CD as observed in the present report is very uncommon, since only 5 cases, including this one, have been reported. We suggest that in CD the primary tumor as well as regional lymph nodes should be completely removed, and the patients should be kept under long-term postoperative observation to check for recurrence.

Castleman Disease↗
PubMed1994

[An autopsied case of pleuro-pulmonary cryptococcosis].

We report a case of pleuro-pulmonary cryptococcosis. An 86-year-old man was admitted to the hospital with dyspnea, a high fever and an oppressive sensation in the chest. Chest X-ray on admission revealed massive pleural effusions, interstitial shadows and consolidation with air bronchograms in both lung fields. The cause of pleural effusion was unknown. The patient died one month later. Autopsy revealed severe pleural cryptococcosis and organizing pneumonia with a small number of cryptococci but without granuloma. To our knowledge, there have been very few documented cases of pleuro-pulmonary cryptococcosis with such massive bilateral pleural effusions.

Aged↗
PubMed1994

[A case of allergic bronchopulmonary fungosis caused by several kinds of fungi].

A 36-year-old man, who had been treated for bronchial asthma since 10 years of age was admitted to Haibara General Hospital because of asthma attack and abnormal chest X-ray shadows. Chest roentgenogram on admission revealed patchy and consolidation shadows in both lung fields. Blood eosinophilia (15%, 1,155/mm3) and elevation of total IgE (7,800 IU/ml) were demonstrated by laboratory examination. Bronchography showed central bronchial ectasia in right B2, B3, B6 and left B1+2, B3 and B6. Investigations of allergy demonstrated elevated specific IgE levels, positive immediate and late skin reactions, positive "dual" asthmatic responses and positive precipitating antibodies for Aspergillus fumigatus, Penicillium luteum and Cladosporium cladosporioides. Aspergillus fumigatus, Penicillium spp. and Cladosporium spp. were cultured from his sputa. From these clinical symptoms and findings of tests of allergy, all three kinds of fungi, Aspergillus fumigatus, Penicillium and Cladosporium, were considered as causative antigens in this case of allergic bronchopulmonary fungosis.

Adult↗
PubMed1993

Establishment and characterization of an erythropoietin-dependent subline, UT-7/Epo, derived from human leukemia cell line, UT-7.

UT-7 is a human leukemic cell line capable of growing in interleukin-3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF), or erythropoietin (Epo) (Komatsu et al, Cancer Res 51:341, 1991). To study the effect of Epo on proliferation and differentiation of UT-7, we maintained the UT-7 cell culture for more than 6 months in the presence of Epo. As a result, a subline, UT-7/Epo, was established. The growth of UT-7/Epo could be supported by Epo but not by GM-CSF or IL-3. UT-7/Epo showed a greater level of heme content and ratio of benzidine-positive staining cells than did UT-7. Butyric acid promoted the synthesis of hemoglobin in UT-7/Epo, but not UT-7. Further, the mRNA concentrations of the c-myb oncogene and GM-CSF receptor beta-subunit were decreased substantially in UT-7/Epo cells. These findings showed that UT-7/Epo cells had progressed further in erythroid development than UT-7 cells, and suggested that long-term culture in Epo had promoted this differentiation. Whereas availability of the Epo receptor (Epo-R) for binding of Epo was reduced in UT-7/Epo cells compared with UT-7 cells, the Epo-R showed a similar affinity for Epo. This observation suggested that change(s) in postreceptor signaling step might be involved in the establishment and maintenance of the UT-7/Epo phenotype.

Butyrates↗
PubMed1993

The Xenopus IP3 receptor: structure, function, and localization in oocytes and eggs.

To study the role of the IP3 receptor (IP3R) upon egg activation, cDNA clones encoding IP3R expressed in the Xenopus oocytes were isolated. By analyses of the primary structure and functional expression of the cDNA, Xenopus IP3R (XIP3R) was shown to have an IP3-binding domain and a putative Ca2+ channel region. Immunocytochemical studies revealed polarized distribution of XIP3R in the cytoplasm of the animal hemisphere in a well-organized endoplasmic reticulum-like structure and intensive localization in the perinuclear region of stage VI immature oocytes. In ovulated unfertilized eggs, XIP3R was densely enriched in the cortical region of both hemispheres in addition to its polarized localization. After fertilization, XIP3R showed a drastic change in its distribution in the cortical region. These results imply the predominant role of the XIP3R in both the formation and propagation of Ca2+ waves at fertilization.

Amino Acid Sequence↗
PubMed1993

Pre- and postmenopausal bone mineral density of the spine and proximal femur in Japanese women assessed by dual-energy x-ray absorptiometry: a cross-sectional study.

To investigate the influence of menopause on bone mineral density (BMD) of Japanese women, BMD of the spine and proximal femur was measured by dual-energy x-ray absorptiometry (DXA) in 220 premenopausal and 166 postmenopausal Japanese women. The peak bone density of the spine in premenopausal women was detected between 35 and 39 years of age, and that of femur before 20. Thereafter spinal and femoral BMD showed a slight decrease, but they did not show a significant decrease until menopause or menstruation became irregular. Duration of substantial bone loss at lumbar spine continued for about 10 years after menopause, but that at the femur was much longer. To investigate the effect of early menopause on bone loss, postmenopausal women were divided into two groups according to the age at onset of menopause. The BMD of postmenopausal women whose menopause occurred before 50 was significantly less over the latter part of life than that of women whose menopause occurred after 50. These results suggest that bone loss is related to menopause or irregular menstruation rather than age per se, and early menopause should be recognized as one of the risk factors for involutional osteoporosis.

Absorptiometry, Photon↗
PubMed1993

A case of renal cell carcinoma with metastasis to the thyroid gland and concomitant early gastric cancer.

Metastatic lesions from renal cell carcinoma are commonly recognized in the lung and bone, however, thyroid metastasis has rarely been reported in the literature. We present herein a case of a man with lung and thyroid metastatic tumors from renal cell carcinoma. Although making a preoperative diagnosis of thyroid metastasis is difficult because there is no established diagnostic criteria, we were able to identify this thyroid lesion as a metastatic tumor from renal cell carcinoma by the pathological findings. Interestingly, hypercalcemia was recognized in this patient whose serum parathyroid hormone (PTH) level was not increased. Moreover, this patient also had early gastric cancer simultaneously, being a so-called 'double cancer'. After surgical resection of the right kidney and stomach, interferon was administered without any efficacy against the metastatic lesions of the lung and thyroid gland.

Carcinoma, Renal Cell↗
PubMed1993

The effects of walking at the anaerobic threshold level on vertebral bone loss in postmenopausal women.

The purpose of this study was to determine the optimal intensity of exercise necessary to prevent the postmenopausal bone loss on the basis of anaerobic threshold (AT). Thirty-three postmenopausal women were randomized to control (group C: n = 12) or two exercise groups (group H and group M). All women performed a treadmill exercise test, and the AT was measured by expired gas analysis. The exercise regimen consisted mainly of walking at a speed that kept the exercise heart rate above the AT (group H: n = 12) or below the AT (group M: n = 9). Exercise was performed for 30 minutes, three times a week for 7 months. The bone mineral density (BMD) of the lumbar vertebrae was measured using dual energy X-ray absorptiometry. The BMD level in group C decreased by 1.7 +/- 2.7%, but there was a significant increase of 1.1 +/- 2.9% in group H. In group M there was a decrease of 1.0 +/- 3.1% which did not differ from group C. In group C, serum osteocalcin and urinary hydroxyproline excretion were significantly increased, but no changes were seen in either of the exercise groups. Urinary calcium significantly decreased in the exercise groups. We conclude that short-term (7 months) exercise with intensity above the AT is safe and effective in preventing postmenopausal bone loss.

Absorptiometry, Photon↗
PubMed1993

Effect of trimebutine maleate on emptying of stomach and gallbladder and release of gut peptide following a solid meal in man.

We investigated the effect of orally administered trimebutine maleate on gastric and gallbladder emptying and on the release of gut peptide, pancreatic polypeptide (PP), and gastrin in humans for 120 min after ingestion of a solid meal. Gastric emptying was measured by a radionuclide technique. Gallbladder emptying was estimated by real-time ultrasonography. The oral administration of 200 mg of trimebutine maleate significantly shortened the lag time in starting gastric emptying (P < 0.05). Considering gallbladder emptying, trimebutine significantly inhibited the fasting emptying induced by neural reflex. Postprandially, there was a tendency toward an accelerated gallbladder emptying in the early phase. Neither the maximal percentage of gallbladder emptying nor the time of peak gallbladder emptying were affected. Trimebutine significantly blunted the post-prandial PP response in the cephalic and gastric phases, reflecting a vagal-cholinergic activity (P < 0.05). The PP response in the intestinal phase was also blunted. Gastrin release was significantly augmented only during the period of fasting after drug administration (P < 0.05). The major effect of trimebutine maleate appears to be a shortening of the lag time at the start of gastric emptying probably via its anticholinergic activity.

Administration, Oral↗
PubMed1993

Isolation of a Drosophila gene encoding a head-specific guanylyl cyclase.

We have isolated and characterized a new guanylyl cyclase gene (dgc1) in Drosophila. The deduced amino acid sequence (683 amino acids) most closely resembled the mammalian soluble-type guanylyl cyclase alpha subunit. The cyclase catalytic domain was highly conserved between the mammalian and Drosophila guanylyl cyclases. The dgc1 mRNA was detected in wild-type heads but not in bodies, and its level was reduced in the mutant eyes absent (eya), indicating that dgc1 is preferentially expressed in the CNS and in the eye. The enriched distribution in the eye suggests that dgc1 may have a role in phototransduction.

Amino Acid Sequence↗
PubMed1993

[A case of hypertrophic obstructive cardiomyopathy with marked T wave changes during the short-term].

A 72-years-old woman was admitted to our hospital for evaluation of giant negative T waves, which appeared for only two days. Chest X-p revealed a cardiomegaly of slight degree and UCG showed ASH (IVS = 21 mm). Coronary arteriography presented no significant stenosis and the left ventricle was spade-shaped. There was a pressure gradient of 65 mmHg between the aorta and the left ventricle during isoproterenol infusion. Furthermore, endomyocardial biopsy showed disarray and fibrosis to a slight degree and fatty degeneration of myocytes with contraction bands. Based on these findings, calcium blocker was administrated under the diagnosis of HOCM. One month after the initiation of this drug, negative T waves gradually became shallow and finally upright with thinning of IVS (12 mm) four month later. We swimise that this T-wave change is primarily based on myocardial hypertrophy as well as being due to the abnormality of myocardial depolarization. We presented a case of HOCM with negative T-wave change of very short duration, which was improved by calcium-blocker and beta-blocker.

Adrenergic beta-Antagonists↗
PubMed1993

Application of in vitro bromodeoxyuridine labeling of oral cancers.

We used immunohistochemical methods to investigate whether in vitro labeling with bromodeoxyuridine (BrdU) of oral cancer tissues is useful in pathological diagnosis. BrdU-positive cells were found around the basal region of the epithelium in normal oral mucosa, in a papilloma specimen and in tissue with moderate dysplasia. The labeling rates (percentage of BrdU-positive cells, LR) for these cases were 1.2%, 6.9% and 7.5%, respectively. In well-differentiated carcinoma, more layers of BrdU positive cells were observed from the basal layer toward the surface. The LR in this region was 13.9-17.0%. In vitro BrdU labeling of oral tumors may be useful in pathological diagnosis, since the LR is lowest in normal tissues, higher in benign tumors, and highest in malignant tumor tissues.

Bromodeoxyuridine↗
PubMed1993

[A case of bronchogenic squamous cell carcinoma associated with Swyer-James syndrome].

Swyer-James syndrome is considered to be a relatively uncommon disease entity presenting with unilateral hyperlucent lung due to hypoplasia of a pulmonary artery and bronchiectasis of the affected lung. Association of bronchogenic carcinoma with Swyer-James syndrome has not apparently been reported in any previous literature, except for one Japanese case. In the present paper, we describe a 48-year-old male individual, who developed poorly differentiated squamous cell carcinoma of the right upper lobe bronchus after he had been diagnosed to have Swyer-James syndrome with unilateral hyperradiancy of the left lung. It is suggested that the bronchial epithelium of the unaffected lung in Swyer-James syndrome is likely to be more exposed to extrinsic carcinogens than that of the affected, underventilated lung, hence resulting in a higher risk of developing bronchogenic carcinoma.

Carcinoma, Squamous Cell↗
PubMed1993

[Electrocardiographic study of sinus bradycardia associated with enterohemorrhagic Escherichia coli O157: H7 infection].

A severe outbreak of hemorrhagic colitis occurred at a kindergarten in Saitama, Japan in October, 1990. Children who were affected by enterohemorrhagic E. coli O157: H7 infection showed apparent bradycardia as well as severe bloody diarrhea, generalized convulsion, or hemolytic uremic syndrome. Cardiac involvement such as bradycardia observed in the patients of this outbreak has not been described in previous reports about EHEC infection, while bradycardia has been well known in typhoid fever due to salmonella typhosa infection. Electrocardiographic examination was performed to evaluate bardicardia, utilizing electrocardiography at rest and Holter's twenty-four hour electrocardiography. In the report, we demonstrate that the bradicardia was due to reduced frequency of sinus node. Both average heart rate and average minimum heart rate of the patients at night (74.0 +/- 5.6 BPM and 57.0 +/- 5.1 BPM, respectively) decreased significantly, as compared with controls (84.6 +/- 9.3 BPM and 66.3 +/- 8.0 BPM respectively) (p < 0.01). CVRR of the patients (0.120 +/- 0.019, respectively) increased significantly as compared with controls (0.090 +/- 0.010, respectively). These results indicate that an activated parasympathetic nervous system, that is, activation of the vagal nerve, might have induced the sinus bradycardia observed in the patients with EHEC infection.

Bradycardia↗