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Biomedical subjects

K Okada

Publications and source records attributed to K Okada.

At least 415 records · Page 23Linked to original sources
PubMed1998

Nephrogenic adenoma in a patient with transitional cell carcinoma of the bladder receiving intravesical bacillus Calmette-Guérin.

A 76-year-old-man was admitted to our hospital for a recurrent bladder tumor. He had received intravesical bacillus Calmette-Guérin (BCG) treatment for a transitional cell carcinoma of the bladder. A follow-up cystoscopy revealed a solitary papillary tumor in the left bladder wall. A transurethral cold cup biopsy revealed a nephrogenic adenoma without any evidence of malignant cells. We discuss the pathogenesis of nephrogenic adenoma and suggest that prolonged cystitis caused by intravesical BCG may play an etiological role.

Adenoma↗
PubMed1998

Numeric aberration of chromosome 17 is strongly correlated with p53 overexpression, tumor proliferation and histopathology in human bladder cancer.

BACKGROUND: This study investigated the relationships between the numeric aberrations of chromosome 17 and p53 expression, the proliferating cell nuclear antigen labeling index (PCNA-LI) and histopathology, to determine their prognostic significance in bladder cancer. METHODS: Using in situ hybridization (ISH) with a biotin-labeled chromosome-specific DNA probe, the copy number of pericentromeric sequences in chromosome 17 were detected within interphase nuclei in formalin-fixed paraffin-embedded sections from 59 nonmetastasized transitional cell carcinomas (TCCs) of the urinary bladder. Expression of p53 and PCNA-LI were determined in serial sections by an immunohistochemical method. RESULTS: The percentage of hyperdiploid cells for chromosome 17 correlated with p53 overexpression (P< 0.002), PCNA-LI (P< 0.002), increasing tumor grade (P< 0.002) and advanced pathologic stage (P< 0.002). The average percentage of hyperdiploid cells was lower in tumors with negative p53 expression than in tumors with p53 overexpression (P< 0.002). Also, more polysomic TCCs were found in muscle-invasive than in superficial cases (P< 0.01 ), and there was a difference in both p53 overexpression or PCNA-LI between disomic and polysomic TCCs (P< 0.01). Patients with chromosome 17 disomic tumors showed less frequent tumor progression than patients with polysomic tumors (P< 0.05). However, chromosome 17 polysomy was an independent prognostic indicator only for patient survival (P< 0.05). CONCLUSION: The occurrence and extent of numeric aberrations of chromosome 17 may be associated with the evolution of aggressive growth in TCC and may be a useful indicator for survival.

Aged↗
PubMed1998

Differential expression of hepatocyte growth factor in papillary and nodular tumors of the bladder.

BACKGROUND: The aim of this study was to investigate the expression of hepatocyte growth factor (HGF) and its receptor (c-met) during bladder tumorigenesis. METHODS: HGF and c-met expression were analyzed immunohistochemically in matched samples of normal, dysplastic, and carcinoma specimens from 49 human bladders resected at the time of radical cystectomy for nonmetastatic transitional cell carcinoma (TCC). The tumors were composed of papillary (n = 22), nodular (n = 16) or mixed papillary and nodular (mixed; n = 11) components. RESULTS: The normal urothelium showed no significant immunoreactivity to HGF. Expression of HGF was observed in 45.5%, 77.3% and 90.9% of specimens demonstrating mild, moderate, and severe dysplastic lesions adjacent to papillary TCCs, respectively, whereas all of the papillary TCC samples were positive for HGF. No immunoreactivity for HGF was found in dysplastic lesions from nodular tumors, and only 2 specimens had positive immunostaining for HGF in the tumor areas (1 showed weak immunostaining and 1 showed HGF immunostaining only in the deeper invasive compartment). Additionally, 3 nodular lesions taken from mixed tumors showed weak immunostaining for HGF while the concurrent papillary lesions were HGF-positive. There was a significant difference of HGF immunoreactivity between papillary and nodular tumors (P < 0.01). c-met immunostaining was consistently detected in all specimens. HGF and c-met immunoreactivity did not significantly correlate with tumor stage and grade, nor with overall patient survival irrespective of the tumor growth pattern. CONCLUSION: These results suggest that HGF expression may play a significant role in the development of papillary TCC.

Aged↗
PubMed1998

Long-term results of definitive treatment in elderly patients with localized prostate cancer.

BACKGROUND: The indication and effectiveness of definitive local treatment for prostate cancer in patients with a limited life expectancy remains to be established. This study is a retrospective analysis of the long-term clinical outcome of elderly patients with localized prostate cancer treated by radiotherapy or a radical prostatectomy. METHODS: From 1982 to 1992, 37 patients with localized prostate cancer, aged 70 years or older, were treated initially by a pelvic lymphadenectomy and then with either external radiotherapy (n = 1 7) or a radical retropubic prostatectomy (n = 20). Lymph node metastasis was negative in all the cases, and no patients received hormonal treatment after the lymphadenectomy. The outcome of all patients was evaluated in June 1997. RESULTS: The 10-year overall and relative survival rates for the radiotherapy group were 27% and 85%, which were not significantly different from the rates of patients in the prostatectomy group (38% and 74%, respectively). The 5-year progression free rates for the radiotherapy group and the prostatectomy group were 63% and 95%, respectively (P= 0.06). CONCLUSION: In elderly patients with localized prostate cancer, the superiority of a radical prostatectomy over radiotherapy was not demonstrated in terms of either overall or relative survival rates, although the progression rate tended to be higher in patients in the radiotherapy group. The indication of definitive treatment in elderly patients should be further studied incorporating a quality of life assessment.

Aged↗
PubMed1998

[A case of tuberculous pyothorax after an interval of four years of finishing with the first treatment for pulmonary tuberculosis].

We reported a case of tuberculous pyothorax which developed at four years after finishing with the first treatment for pulmonary tuberculosis. A 50-year-old female was admitted to our hospital with right chest pain. Tuberculous pyothorax was diagnosed by means of polymerase chain reaction (PCR method) of pleural effusion and of histological findings of the pleural section. She was cured by operation, pleural drainage and anti-tuberculous drugs. The bone scincigram of 99mTc revealed accumulation in the right 9th rib, tuberculous empyema might have been a secondary development from osteomyelitis.

Empyema, Tuberculous↗
PubMed1998

[Early manifestation of septic shock and disseminated intravascular coagulation complicated by acute myocardial infarction in a patient suspected of having Legionnaires' disease].

Legionellosis is an important cause of severe pneumonia in the community. Inadequate therapy will lead to respiratory distress syndrome, disseminated intravascular coagulation (DIC) and finally fatal multiple organ failure. We encountered a rare case in which early manifestation included septic shock and DIC complicated by acute myocardial infarction (AMI) suspected to be derived from Legionnaires' disease. A 54-year-old healthy female complained of lumbago, high fever and dry cough 10 days after visiting a hot spring spa. She was emmergently admitted due to shock. Physical examination demonstrated hypotension, high fever, course creakle in the right lower lung. Hepatosplenomegaly, lymphadenopathy and eruption were not found. WBC count was 34600/microliters with nuclear shift. CRP elevated. FDP, D dimer and TAT also elevated CPK elevated with dominance of the MB isozyme. Chest roentogenography revealed congestive heart failure, pleural effusion and obscure pneumonic shadow and EKG showed ST segment elevation in leads I, II, III, aVF, V4, V5, and V6. The patient was diagnosed as having septic shock, DIC and AMI. She was treated with gabexate mesilate, high dose methyl prednisolone and dopamine hydrochloride as well as piperacillin, meropenem, isepamycin and fluconzaole. Despite intensive care, the blood pressure fell again and pneumonia had progressed on the 8th hospital day. These antibiotics appeared to be ineffective. Erythromycin was then administered and a dramatic effect. was obtained as the patient recovered. Serum titer of Legionella pneumophila (serogroup 1) rose to 128-fold 2 weeks after the onset. Other serum titers such as Chlamydia psittaci, Rickettsia, Mycoplasma were all negative. Cultures obtained from the sputum, throat swab, urine and blood did not yield any microorganisms. Although the diagnosis could not be confirmed because the titer did not elevate over 256-fold of 4-fold within 2 weeks after the onset, Legionella infection was highly suspected from the clinical features. This is a rare case in which septic shock and DIC with AMI preceded pulmonary symptoms in a non-immunocompromised patient.

Diagnosis, Differential↗
PubMed1998

Pharmacokinetic evaluation of amphotericin B in lung tissue: lung lymph distribution after intravenous injection and airspace distribution after aerosolization and inhalation of amphotericin B.

We have studied the pharmacokinetics of amphotericin B (AmB) in lung lymph circulation and bronchial-wash fluid after intravenous infusion and inhalation, respectively. For two experiments with awake sheep, we used lung lymph fistulas and tracheotomy. In experiment 1, AmB concentrations in plasma and lung lymph after intravenous infusion of AmB (1 mg/kg of body weight) over 1.5 h were measured. The mean peak in plasma level was 756.0 +/- 188.8 ng/ml at 3 h after the start of infusion, and the level then decreased gradually to 194.8 +/- 28.9 ng/ml at 24 h. The stable and maximal levels in lung lymph last 5 to 9 h after the start of AmB infusion. The concentrations in lung lymph after 9 h were slightly higher than those in plasma. Thus, the lung lymph-to-plasma ratio of AmB concentrations increased gradually during infusion, and the ratio was more than 1.0 after the end of infusion, suggesting that AmB could be easily moved from plasma to pulmonary interstitium and/or lung lymph circulation. In another experiment, 5 or 30 mg of aerosol AmB was inhaled, and the concentration of AmB in the bronchial-wash fluid was determined by bronchoalveolar lavage. The peak AmB concentration in the fluid was observed at 0.5 h. After that, AmB was slowly eliminated over 24 h. The area under the concentration-time curve for 30 mg of inhaled AmB was higher than that for 5 mg, but maximum concentrations of AmB in serum for 5 and 30 mg were almost similar. These observations identify the pharmacokinetic characteristics of AmB in the lung and may provide a new insight into the strategy for clinical treatment of fungal pneumonia.

Administration, Inhalation↗
PubMed1998

DNA supercoiling factor localizes to puffs on polytene chromosomes in Drosophila melanogaster.

DNA supercoiling factor (SCF) was first identified in silkworm as a protein that generates negative supercoils in DNA in conjunction with eukaryotic topoisomerase II. To analyze the in vivo role of the factor, we cloned a cDNA encoding Drosophila melanogaster SCF. Northern analysis revealed 1.6- and 1.8-kb mRNAs throughout development. The longer mRNA contains an open reading frame that shares homology with mouse reticulocalbin whereas the shorter one encodes a truncated version lacking the N-terminal signal peptide-like sequence. An antibody against SCF detected a 45-kDa protein in the cytoplasmic fraction and a 30-kDa protein in the nuclear fraction of embryonic extracts. Immunoprecipitation suggests that the 30-kDa protein interacts with topoisomerase II in the nucleus, and hence that it is a functional form of SCF. Immunostaining of blastoderm embryos showed that SCF is present in nuclei during interphase but is excluded from mitotic chromosomes. In larvae, the antibody stained the nuclei of several tissues including a posterior part of the salivary gland. This latter staining was associated with natural or ecdysteroid-induced puffs on polytene chromosomes. Upon heat treatment of larvae, the staining on the endogenous puffs disappeared, and strong staining appeared on heat shock puffs. These results implicate SCF in gene expression.

Amino Acid Sequence↗
PubMed1998

Blockade of neuronal nitric oxide synthase alters the baroreflex control of heart rate in the rabbit.

In previous studies we used NG-nitro-L-arginine (L-NNA) to investigate the role of nitric oxide (NO) in baroreflex control of heart rate (HR) and renal sympathetic nerve activity (RSNA). L-NNA increased resting mean arterial pressure (MAP), decreased HR, and did not change or slightly decreased RSNA. These changes complicated the assessment of the central effects of NO on the baroreflex control of HR and RSNA. Therefore, in the present study the effects of the relatively selective neuronal NO synthase inhibitor 7-nitroindazole (7-NI) on the baroreflex control of HR and RSNA were investigated in rabbits. Intraperitoneal injection of 7-NI (50 mg/kg) had no effect on resting HR, MAP, or RSNA. 7-NI significantly reduced the lower plateau of the HR-MAP baroreflex curve from 140 +/- 4 to 125 +/- 4 and from 177 +/- 10 to 120 +/- 9 beats/min in conscious and anesthetized preparations, respectively (P < 0.05). In contrast, there was no significant difference in the RSNA-MAP curves before and after 7-NI administration in conscious or anesthetized preparations. These data suggest that blockade of neuronal NO synthase influences baroreflex control of HR but not of RSNA in rabbits.

Animals↗
PubMed1998

Respiratory quotient in patients with non-insulin-dependent diabetes mellitus treated with insulin and oral hypoglycemic agents.

The respiratory quotient (RQ) reflects the amount of energy derived from carbohydrate as apposed to fat metabolism. To assess the metabolic state of patients with non-insulin-dependent diabetes mellitus, the RQ was measured five times a day (at 09.00, 11.00, 13. 00, 14.00, and 17.00 h) in 20 healthy subjects and 60 diabetic patients. Diabetic patients treated with insulin or sulfonylurea showed significantly higher RQ values than normal subjects and nontreated diabetic patients. Diabetic patients without treatment showed higher glucose levels, and their RQ values were significantly lower than those of treated patients. There was a significant inverse correlation between RQ and blood glucose levels at 11.00 h (r = -0.361, p < 0.01) in diabetic patients, but no significant relation with HbA1c. Treated diabetic patients with a higher body mass index tended to show a higher RQ than those with a lower one (r = -0.269, p = 0.083). Within 1 year, 7 of 13 patients, who had RQ > 1.0, gained more than 3 kg, while only 5 of the remaining 32 treated diabetic patients gained more than 3 kg (p < 0.05). This demonstrates that diabetic patients with a higher RQ tended to gain weight despite the use of insulin or oral hypoglycemia agents. The RQ increased by infusing both insulin and glucose in normal subjects. These results suggest that a high RQ results from excess insulin and excess food. The RQ is a good predictor of weight gain in diabetic patients treated with either insulin or oral hypoglycemic agents.

Calorimetry, Indirect↗
PubMed1998

Angiotensin-converting enzyme inhibition delays pulmonary vascular neointimal formation.

Primary pulmonary hypertension (PPH) is a disease characterized pathologically by pulmonary artery medial hypertrophy, adventitial thickening, and neointimal proliferation. Increasing recognition of the importance of remodeling to the pathogenesis of PPH suggests new therapeutic possibilities, but it will be necessary to (1) identify essential mediators of remodeling, and (2) demonstrate that inhibiting those mediators suppresses remodeling before new antiremodeling therapies can be considered feasible. The effect of angiotensin-converting enzyme (ACE) inhibition on pulmonary vascular remodeling was studied in a newly developed rat model in which neointimal lesions develop between 3 and 5 wk after monocrotaline injury is coupled with increased pulmonary artery blood flow after contralateral pneumonectomy. Neointimal formation was significantly suppressed at 5 wk by ACE inhibition whether it was started 10 d before or 3 wk after remodeling was initiated, although medial hypertrophy and adventitial thickening still developed. By 11 wk, the extent of neointimal formation in rats treated with ACE inhibition was similar to rats without ACE inhibition at 5 wk. Pulmonary artery pressures and right ventricular weights correlated with the extent of neointimal formation. Northern blot analysis and in situ hybridization demonstrated marked suppression of lung tropoelastin and type I procollagen gene expression in the presence of ACE inhibition. An angiotensin II type I receptor antagonist partially, but not completely, replicated the effects of ACE inhibition. These data suggest that the tissue angiotensin system may be a target for therapeutic efforts to suppress the vascular remodeling that is characteristic of primary pulmonary hypertension.

Angiotensin Receptor Antagonists↗
PubMed1998

Tamsulosin: alpha1-adrenoceptor subtype-selectivity and comparison with terazosin.

Selectivity of tamsulosin and terazosin to functional alpha1-adrenoceptors was examined. Both drugs competitively inhibited the contractile responses to noradrenaline in different tissues where the responses were mediated through the alpha1D-, alpha1B- or alpha1L-subtype. Together with the affinities obtained in the binding study with cloned (alpha1a, alpha1b, alpha1d) and native (alpha1A and alpha1B) subtypes, the selectivity of tamsulosin was alpha1A>alpha1L, alpha1D>alpha1B. Terazosin had lower affinity at various subtypes than tamsulosin, but showed relatively high selectivity to the alpha1D-subtype. In the human prostate, tamsulosin was more than 30-fold higher in affinity than terazosin in functional and binding studies.

Adrenergic alpha-Antagonists↗
PubMed1998

Inter-laboratory difference among eleven clinical laboratories in the Okayama City area.

The aim of the present study was to find the cause of inter-laboratory differences in laboratory test data and to examine whether control assessment helps to reduce inter-laboratory differences. Blood and serum samples of one healthy subject and one subject with liver cirrhosis were analyzed by 11 laboratories in the Okayama City area. No differences were found in the assay units of 26 tests surveyed. However, considerable differences were observed in test data, reference interval, and clinical level (CL), though most laboratories pointed out that the test data for the normal subject was within the reference intervals and those for the patient with liver cirrhosis showed abnormalities in tests for liver function. The difference in reference intervals was serious in the tests of direct bilirubin (D-Bil), thymol turbidity test (TTT), alkaline phosphatase (ALP), gamma-glutamyltranspeptidase (GGTP) and choline sterase. Marked differences in CLs were found in the tests of D-Bil, TTT, ALP, GGTP, creatine phosphokinase, amylase, heavy density lipoprotein cholesterol and white blood cell count. However, three hepatologists independently suggested that such inter-laboratory differences would not seriously affect a clinical decision on the disease status of the cirrhotic patient. Most tests that showed a trend error in a recent quality control survey appeared to have the same trend in the present study. These results indicate that inter-laboratory differences occur at various levels and control assessment are helpful in establishing, and therefore reducing, the level of inter-laboratory differences.

Aged↗
PubMed1998

Plasma (1-->3)-beta-D-glucan measurement and polymerase chain reaction on sputum as practical parameters in Pneumocystis carinii pneumonia.

We report a case of Pneumocystis carinii pneumonia in a patient with acquired immunodeficiency syndrome diagnosed and monitored with polymerase chain reaction (PCR) for Pneumocystis carinii on sputum and measurement of plasma (1-->3)-beta-D-glucan (G-test). Results of both studies paralleled the clinical and radiographic improvement. However, the plasma (1-->3)-beta-D-glucan level remained higher than normal when PCR for Pneumocystis carinii became negative in sputum. Both PCR for Pneumocystis carinii on sputum and measurement of plasma (1-->3)-beta-D-glucan are useful for noninvasive diagnosis and monitoring of Pneumocystis carinii, although further investigation is necessary to quantify their relationship.

AIDS-Related Opportunistic Infections↗
PubMed1998

[Association between social environment and aging of the brain: evaluation with the event-related potential P300].

PURPOSE AND METHODS: To investigate the association between social environment and aging of the brain, we studied P300 event-related evoked potentials in 95 normal elderly subjects living in different social environments. The subjects were divided into two groups: 22 healthy people living in old-age homes (average age 76.5 +/- 5.6 years, average Hasegawa Dementia Scale-Revised 27.4 +/- 2.5), and 93 healthy people living in their own homes (average age 74.1 +/- 5.4 years, average Hasegawa Dementia Scale-Revised 28.3 +/- 2.3). Target and Novelty P300 were recorded by using an auditory oddball paradigm. There were no differences in risk factors for strokes or in findings on magnetic resonance imaging between the two groups. RESULTS: Cognitive function (Okabe's Score and Koh's Block Design Test) were lower in those living in an old-age home than in those living in their own homes. Both target and novelty N100 examinations showed no significant differences in amplitude or latencies between the two groups. However, P300 latencies were larger among those living in an old-age home than among those living in their own homes; P300 amplitudes in the two groups were similar. Those living in an old-age home also had greater age-associated declines in function, as shown by longer latencies in target P300 than in novelty P300. CONCLUSION: Social-environmental factors are closely associated with the aging of the brain.

Aged↗