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Biomedical subjects

H Miyake

Publications and source records attributed to H Miyake.

At least 181 records · Page 10Linked to original sources

Calcium ionophore, ionomycin inhibits growth of human bladder cancer cells both in vitro and in vivo with alteration of Bcl-2 and Bax expression levels.

PURPOSE: The objective of this study was to characterize the antiproliferative effects of the calcium ionophore, ionomycin on the human bladder cancer cell line HT1376 both in vitro and in vivo. MATERIALS AND METHODS: The in vitro growth rate of HT1376 after treatment with ionomycin was measured by using the MTT assay. The apoptotic features in HT1376 after ionomycin treatment were evaluated by flow cytometric analysis and DNA degradation assay. Bcl-2 and Bax expression levels in HT1376 after ionomycin treatment were examined by Northern and Western blot analyses. The effects of intratumoral injection of ionomycin on the growth of subcutaneous HT1376 tumors established in athymic nude mice were then tested. The efficacy of combined treatment with ionomycin and cisplatin against HT1376 growth was also examined. RESULTS: The in vitro growth rate of HT1376 was suppressed by ionomycin in a dose- and time-dependent manner, and characteristic apoptotic DNA degradation was observed in HT1376. Ionomycin treatment caused a marked decrease in the ratios of Bcl-2 to Bax mRNA and protein in HT1376 cells. Intratumoral injection of ionomycin into subcutaneous HT1376 tumors reduced the tumorigenicity in nude mice. Furthermore, these in vivo growth-inhibitory effects of ionomycin were significantly enhanced by pretreatment with cisplatin. CONCLUSIONS: These findings suggest that ionomycin-based therapy could be used as a novel therapeutic strategy for advanced bladder cancer through the effective induction of apoptosis by decreasing the ratio of Bcl-2 to Bax.

Animals↗

Beneficial effects of MET-88 on left ventricular dysfunction and hypertrophy with volume overload in rats.

We examined the effects of MET-88 on haemodynamics and cardiac hypertrophy in rats with an aortocaval shunt (A-V shunt). On the day of surgery, an A-V shunt was produced by using an 18-gauge needle in Wistar rats as described by Garcia and Diebold. MET-88 and captopril were orally administered to rats 1 week after surgery, and the administration was continued for 3 weeks. Four weeks after the surgery, A-V shunt-operated rats had biventricular hypertrophy and higher right atrial pressure (RAP) and left ventricular end-diastolic pressure (LVEDP) than sham-operated rats. Compared with untreated A-V shunt rats, those treated with MET-88 showed significant attenuation of the development of left ventricular (LV) hypertrophy and of the increased LVEDP. Captopril-treated A-V shunt rats also failed to show increases in LV weight and LVEDP. In in vitro studies, MET-88 had no effect on renin and angiotensin-converting enzyme (ACE) activities in the plasma of normal rats. These results suggest that MET-88 improved LV hypertrophy and LV dysfunction in rats with an A-V shunt. Furthermore, the data indicate that the beneficial effects of MET-88 may be attributed to some pathway, not involving the renin-angiotensin system, such as myocardial energy metabolism, venous return, etc. We conclude that MET-88 may be a novel agent for the therapy of chronic heart failure.

Animals↗

Analysis of Helicobacter pylori binding site on HEp-2 cells and three cell lines from human gastric carcinoma.

Helicobacter pylori (H. pylori) is a pathogen responsible for chronic gastritis and peptic ulcer diseases. It colonises the gastric mucus layer and adheres to the gastric epithelial cell surface. As this adherence is the first step of infection, it is important to study the adherence mechanism. The aim of this study was to analyse the specific binding assay of H. pylori to HEp-2 cells and three gastric phenotype cell lines, AGS, MKN-45 and AZ-521. H. pylori NCTC 11637 grown on agar plates was harvested and used in experiments. H. pylori was inoculated to pre-cultured cell monolayers. Adhered bacteria were labelled with an anti-H. pylori antibody and an FITC-conjugated secondary antibody and quantified by using a fluorescent plate reader. Microbial adherence to HEp-2 cells increased with incubation time and incubated concentration of H. pylori. No further increase was obtained with four or more hours of incubation or with a concentration of 4 x 10(7) bacteria/well or more. Scatchard analysis revealed a linear plot and the Bmax value was 88.3. Similar adherence patterns were obtained when AGS, AZ-521 and MKN-45 cells were used for adherence assays, but they had a lower binding affinity than HEp-2 cells and AZ-521. MKN-45 cells had less receptors than HEp-2 and AGS cells. In conclusion, H. pylori adhered to the cell surface could be quantified by this assay method. H. pylori adhesion to cell surfaces has a single population of binding site and one type of binding site on HEp-2, AGS, AZ-521 and MKN-45 cells.

Adhesins, Bacterial↗

Development of ergometer attachment for power and maximum anaerobic power measurement in swimming.

The ergometer can be a versatile means of measurement if attachments are developed for special purposes or if attachment is developed for multi-uses. In this study, an ergometer attachment for the measurement of power was designed and the measurement of power and the maximum anaerobic power in swimming was tested. A rotation drum was attached to one pedal of an ergometer. The rotation of this drum was synchronized with the rotation of the pedal. One end of a wire for a traction by a swimmer was connected to the drum. The other end of the wire was attached to a belt around the waist of a swimmer. The swimmer swam at full strength, thus causing the drum to rotate. The rotational velocity of the drum was detected as voltage by a magnetic permanent motor and transformed to wire tractional velocity; this velocity was equal to swimming velocity. The wire tension (= load) was controlled by a load adjusting lever of the ergometer. This wire tension was equal to the load which was added to the swimmer. The power calculation was based on a curved regression equation approximated from the load and the velocity. This equation was shown as follows; (P + a) (v + b) = (P0 + a)b or its development (P + a)v = b(P0 - P) and provided that P: force or load, v: swimming velocity, P0: maximum tractional force, a and b: constants. This ergometer attachment made it possible to measure and evaluate the power and the maximum anaerobic power in swimming with ease and at low cost. Measurement and evaluation are easily performed using the system, which is just one example of the possible applications of the ergometer.

Adult↗

Zung's depression scale as a predictor of death in elderly people: a cohort study in Hokkaido, Japan.

The relation between each question in the Self-rating Depression Scale (SDS) of Zung and mortality in elderly people was investigated. Subjects were 2,166 inhabitants aged from 60 to 74 years in the Hidaka district of Hokkaido Prefecture, Japan, who were the same as in our previous prospective study concerning mental depression and mortality (J. Epidemiol. 1997). They were followed until February 1996. Among the original 20 questions of the SDS, 12 ones showed significant risk ratio for mortality (those whose score was 3 or 4 vs 1 or 2; P < 0.01). The mortality of those whose average score of the 12 questions was more than 2.4 (severe depression) was 157.2 per 1,000, which was about 5.8 time as high as that of those who were not depressive (average score < 2.0). The 12 questions showed different risk ratios concerning the mortality of cancer, heart disease and cerebrovascular disease. The questions "Morning is when I feel the best" and "My heart beats faster than usual," e.g., showed a significant risk ratio only for the mortality of heart disease (3.96) and for that of cerebrovascular disease (16.49), respectively (P < 0.01). Similar results were obtained from the subjects without respective diseases at the time of survey. Using these 12 questions, the risk for death and its cause can be estimated to a certain extent, and consequently, social supports can be given more effectively and more carefully.

Aged↗

Life span of Japanese male medical doctors.

There have been few reports with regard to the life spans of medical doctors. The status of the medical doctors graduating from 1926 to 1974, alive or dead as of October 1996, was ascertained on the basis of the list of graduates from the School of Medicine, Hokkaido University. Excluding data on female doctors and those who died in battle during World War II, data on a total of 3,982 doctors were available for study. Their mortality as of October 1996 decreased in parallel with the graduation year. Their mean future life span at graduation was estimated to be about 52.88 years (95% CI, 52.45-53.31) through linear regression (r = 0.992). Their mean age at graduation was 25.17 years. This was not different from the future life expectancy at 25 years of age of the general population (52.35 years). The future life span of surgeons and gynecologists-obstetricians was shorter than that of the doctors of basic medical sciences and internal medicine. This difference might be accounted for by factors peculiar to each speciality (e.g., exposure to blood) or by the degree of stress from work.

Age Factors↗

Elevation of urokinase-type plasminogen activator and its receptor densities as new predictors of disease progression and prognosis in men with prostate cancer.

We examined whether two newly defined parameters, the density of urokinase-type plasminogen activator (uPAD) and the density of its receptor (uPARD), which were determined by dividing the serum levels of uPA and uPAR by the prostate volume, respectively, could be used as predictors of the progression and prognosis of prostate cancer (PC). Serum levels of uPA and uPAR in 40 healthy controls, 70 patients with benign prostatic hypertrophy (BPH) and 80 patients with PC were measured by a sandwich enzyme immunoassay, and prostate volume was measured by ultrasonography. The mean levels of uPAD and uPARD in patients with PC were significantly higher than those in healthy controls and patients with BPH. Furthermore, the uPAD and uPARD levels in PC patients with metastasis were significantly elevated compared with those in patients without metastasis. Among patients who underwent radical prostatectomy, the levels of uPAD and uPARD in patients with pathologically organ-confined disease were significantly lower than in those with advanced disease. The overall survival rate of PC cancer patients with elevated levels of either uPAD or uPARD, or of both, was significantly lower than that of patients with normal levels of uPAD and uPARD. In addition, Cox's multivariate analysis revealed that the elevation of uPAD or uPARD level, or of both, was strongly associated with overall survival in PC patients. These findings suggest that the elevation of uPAD or uPARD, or of both, could be used as new predictors of progression and prognosis in patients with PC.

Adult↗

Epidemiology of childhood brain tumors in Japan.

Using the vital statistics issued annually by the Japanese Government from 1960 to 1994, the mortality of brain tumors during childhood (0-14 years of age) in Japan was estimated. Since there are few nationwide registries of childhood cancers with a sufficiently high registration rate, the incidence of brain tumors was calculated using the Registry of Childhood Malignancies in Hokkaido Prefecture from 1969 to 1996. Though the mortality due to malignant diseases as a whole during childhood has been decreasing, and though there should be progress in therapeutic methods, the mortality due to brain tumors in children has been increasing. The incidence of brain tumors in Hokkaido Prefecture has been increasing as well. There was no tendency for the incidence of medulloblastoma to decrease. The incidence of childhood brain tumors has been increasing in Japan, though the cause is unknown. The period of the present study corresponded to a period of high economic growth. Thus, a study on environmental factors would be interesting.

Adolescent↗

[Clinical manifestations and chest radiographic and CT findings of round pneumonia in adults].

Whereas round pneumonia in children is well known, there are few reports of this condition in adults. Chest radiographs, CT findings, clinical manifestations, and peripheral blood results in 14 cases of round pneumonia in 14 adults were evaluated. Round pneumonias ranged in size from 1 to 7 cm. Only round pneumonia was seen in 12 cases, whereas other consolidations besides round pneumonia were present in 2 cases. Eleven of 14 cases of round pneumonia were located in the lower lobes, and 8 of these 11 cases were in the superior segment of the lower lobe. Round pneumonia showed faint density in 9 cases and clear density in 5, while the margin was slightly ill-defined in 10 and well-defined in 4. No characteristic features of round pneumonia were shown on CT scan. CT showed other consolidations besides round pneumonia in 7 of 9 cases in which CT scan was carried out. Most large-sized (more than 2 cm) round pneumonias were associated with fever and elevated WBC and CRP, whereas most small (less than 2 cm) round pneumonias were associated with normal blood results and no fever. Round pneumonia in adults is not uncommon. Most round pneumonias present as slightly dense or ill-defined masses in the posterior subpleural region of the lower lobe. Round pneumonia is suggested by a history of cough, fever, elevated WBC and CRP, and a recent chest radiograph with normal findings.

Adult↗

[Expression of CD44 variant isoform in urine samples of urothelial cancer patient].

CD44v8-10 variant isoform is frequently expressed in many kinds of cancers. We have already reported that 77% of bladder cancer specimens expressed CD44v8-10 and using CD44v8-10/CD44v10 competitive reverse transcription-polymerase chain reaction (CC-RT-PCR), we detected exfoliated urothelial cancer cells in urine samples of urothelial cancer patients (Int J Cancer 79: 560, 1998, J Urol 160: 2004). In this paper, we review the expressing of CD44 variant isoform in various kinds of cancers, and the principle of CC-RT-PCR which can be a novel screening method for urothelial cancer.

Carcinoma, Transitional Cell↗

Relative expression of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 in mouse renal cell carcinoma cells regulates their metastatic potential.

To clarify the significance of the balance between matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) in the progression of renal cell carcinoma, we transfected both the MMP-2 and TIMP-2 genes simultaneously into RenCa, a mouse renal cell carcinoma cell line that does not express detectable levels of either MMP-2 or TIMP-2 mRNAs, and established several clones with various MMP-2:TIMP-2 expression ratios. On the basis of the quantitative evaluation of the MMP-2: TIMP-2 mRNA expression ratio by Northern blot analysis, we selected a clone overexpressing MMP-2 alone (RenCa/M), a clone overexpressing TIMP-2 alone (RenCa/T), and two kinds of clones overexpressing both, i.e., one with a high (RenCa/MTh) and one with a low (RenCa/MTl) MMP-2: TIMP-2 ratio, to compare the tumor cell phenotypes. In an in vitro tumor cell invasion assay, the MMP-2:TIMP-2 ratios of the RenCa sublines were directly correlated with their invasive potential. The invasive abilities of the parental RenCa cells induced by conditioned media from RenCa sublines were also correlated with the MMP-2:TIMP-2 ratios of the sublines. The cell adhesion assay showed the inverse correlation between the MMP-2 expression levels in the sublines and their cell adhesion to several extracellular matrix components. Furthermore, when injected i.v. or into the renal subcapsule in syngeneic mice, RenCa sublines formed metastatic nodules in the lungs, and the number of nodules was correlated with the MMP-2:TIMP-2 ratio of each clone. In contrast, despite the growth-inhibitory effects of TIMP-2 overexpression, MMP-2 overexpression had no effect on either proliferation in vitro of RenCa sublines or on their growth as tumors in vivo. These results suggest that the MMP-2:TIMP-2 expression ratio is a critical factor in the invasion and metastasis of renal cell carcinoma.

Animals↗

Progression to androgen independence is delayed by adjuvant treatment with antisense Bcl-2 oligodeoxynucleotides after castration in the LNCaP prostate tumor model.

Bcl-2 has emerged as a critical regulator of apoptosis in a variety of cell systems and is up-regulated during progression to androgen independence in prostate cancer cells. The objectives of this study were to characterize changes in Bcl-2 after androgen withdrawal and during progression to androgen independence in the human prostate LNCaP tumor model and determine whether adjuvant use of antisense Bcl-2 oligodeoxynucleotides (ODNs) with androgen ablation delays progression to androgen independence. Bcl-2 expression in LNCaP cells is down-regulated to undetectable levels by androgen in vitro and up-regulated after castration in vivo. Antisense Bcl-2 ODN treatment reduced LNCaP cell Bcl-2 messenger RNA and protein levels by >90% in a sequence-specific and dose-dependent manner at concentrations >50 nM. Bcl-2 mRNA levels returned to pretreatment levels by 48 h after discontinuing treatment. Athymic male mice bearing SQ LNCaP tumors were castrated and injected i.p. with 12.5 mg/kg/day with two-base mismatch ODN control, reverse polarity ODN control, or antisense Bcl-2 ODN. Tumor volume in control mice gradually increased 5-fold (range, 3-6) by 12 weeks after castration compared to a 10-50% decrease in precastrate tumor volume in mice treated with antisense Bcl-2 ODN. Changes in serum PSA paralleled changes in tumor volume, increasing 4-fold faster above nadir in controls than in mice treated with antisense Bcl-2 ODN. After decreasing 70% by 1 week after castration, PSA increased 1.6-fold above precastrate levels by 11 weeks in controls while staying 30% below precastrate levels in antisense-treated mice. In a second group of experiments, LNCaP tumor growth and serum PSA levels were 90% lower (P<0.01) in mice treated with antisense Bcl-2 ODN compared with mismatch or reverse polarity ODN controls. These results support the hypothesis that Bcl-2 helps mediate progression to androgen independence and is an appropriate target for antisense therapy.

Androgens↗

Effect of intermittent liver ischemia on outcome in patients with hepatocellular carcinoma on liver cirrhosis.

The influence on postoperative liver function of intermittent normothermic hepatic ischemia in cirrhotic patients was studied retrospectively. The mean total ischemia time was 88 (range 30-140) minutes in the hemi-hepatic occlusion group, and 68 (range 10-187) minutes in the total occlusion group. There were no operative deaths due to hepatic failure. Postoperative liver function improved within 1 week of the operation. There was no significant difference in the incidence of postoperative complications between the groups. Thus normothermic hepatic ischemia is tolerated for up to 180 minutes in the cirrhotic liver when an intermittent technique (15 minutes clamped and 5 minutes unclamped) is used.

Carcinoma, Hepatocellular↗

Utility of Competitive Reverse Transcription-Polymerase Chain Reaction Analysis of Specific CD44 Variant RNA for Detecting Upper Urinary Tract Transitional-Cell Carcinoma.

Recently, we developed a novel molecular approach, CD44 v8-10/CD44 v10 competitive reverse transcription-polymerase chain reaction (CC-RT-PCR), to detect a sparse population of cancer cells overexpressing CD44v8-10 among a much larger population of nonneoplastic cells in body fluids by the measurement of the transcriptional level of CD44v8-10 relative to that of CD44v10. We have shown the utility of CC-RT-PCR in diagnosing disease using urine samples from patients with bladder cancer. In this study, we initially examined the expression of CD44 splice variants in human upper urinary tract transitional-cell carcinomas (UUT-TCCs) and their adjacent normal urinary tissues by RT-PCR. Any CD44 variant isoforms were barely detectable in normal urinary tissues, whereas CD44v8-10 was predominantly expressed in 21 of the 25 UUT-TCC specimens (84%). We then applied CC-RT-PCR to spontaneously voided urine samples from 40 patients with UUT-TCC and 40 patients with benign urologic diseases. The CC-RT-PCR analysis revealed that all of the samples from patients with benign diseases presented a predominant expression of the CD44v10 transcript, whereas 26 of the 40 samples from patients with UUT-TCC dominantly expressed the CD44v8-10 transcript. In addition, the positive rate obtained by the CC-RT-PCR analysis was significantly higher than that obtained by cytologic examination, especially in patients with low-grade UUT-TCC. These findings strongly suggest that CC-RT-PCR is a useful noninvasive tool for the diagnosis of UUT-TCC.

Journal Article↗

[Late phase II clinical study of RP56976 (docetaxel) in patients with advanced/recurrent head and neck cancer].

A late phase II clinical study of RP56976 (docetaxel), a new anticancer agent for advanced/recurrent head and neck cancer, was conducted in 29 institutions all over Japan as a multi-institutional cooperative study. Docetaxel was administered by 1 to 2-hour intravenous infusion at a dose of 60 mg/m2 every 3 to 4 weeks. Of 63 patients eligible in this study, 59 were judged as complete cases. Complete response (CR) was observed in 1 patient, partial response (PR) in 13, no change (NC) in 25, and progressive disease (PD) in 20, for an overall response rate of 22.2% (14/63, 95% CI: 12.7-34.5%) in eligible cases, and 23.7% (14/59, 95% CI: 13.6-36.6%) in complete cases. Previously treated patients showed a 17.9% (10/56) response rate, whereas treatment--naive patients showed a 57.1% (4/7) response rate. Among 46 patients who received prior chemotherapy, one CR and 7 PR were observed with a 17.4% response rate. Major hematological toxicities were leucopenia in 95.1% (> or = grade 3, 59.7%) and neutropenia in 90.3% (> or = grade 3, 79.0%). Other severe toxicities (> or = grade 3) included anorexia in 9.7% (6 cases), diarrhea in 3.2% (2 cases), dyspnea in 3.2% (2 cases), and fatigue in 3.2% (2 cases). One patient had a grade 3 interstitial pneumonia; however, symptoms were resolved by the administration of corticosteroids. During this study, one patient died due to multiple organ failure (MOF) caused by disseminated intravascular coagulation (DIC), and this case was reported as a therapy-related death. Based on these results, docetaxel is an active agent for treatment of head and neck cancer.

Adenocarcinoma↗

Highly specific and sensitive detection of malignancy in urine samples from patients with urothelial cancer by CD44v8-10/CD44v10 competitive RT-PCR.

CD44 is a widely expressed cell surface adhesion molecule in which various isoforms arise from alternative RNA splicing mechanism. Overexpression of specific CD44 splice variant, i.e., CD44v8-10, has been found in several human malignancies and is considered to be associated with tumor progression and metastasis. We have demonstrated a novel molecular approach, CD44v8-10/CD44v10 competitive reverse transcription-polymerase chain reaction (CC-RT-PCR) for the detection of cancer cells overexpressing CD44v8-10 by the measurement of the transcriptional level of CD44v8-10 relative to that of CD44v10 (v8-10/v10 ratio). In this study, we initially examined the expression of CD44 splice variants in human urothelial cancers and their adjacent normal urinary tissues by RT-PCR. Any CD44 variant isoforms were barely detectable in normal urinary tissues, whereas CD44v8-10 was predominantly expressed in 23 of the 30 (77%) urothelial cancer specimens. We then applied CC-RT-PCR to spontaneously voided urine samples from patients with 80 urothelial cancer and 50 various benign urologic diseases. The CC-RT-PCR analysis revealed that all of the samples associated with benign diseases presented a predominant expression of the CD44v10 transcript (the v8-10/v10 ratios = 0.00-0.87), whereas 62 of the 80 samples associated with urothelial cancers mostly expressed the CD44v8-10 transcript (the v8-10/v10 ratios > 1.00). In addition, the positivity rate obtained by the CC-RT-PCR analysis was high regardless of the pathological grade of the urothelial cancers, although the sensitivity of the cytological examination declined with decreasing tumor grade. Our findings suggest strongly that CC-RT-PCR is a non-invasive useful tool for the diagnosis of urine samples from patients with urothelial cancer.

Adolescent↗

Aberrant crypt foci of the colon as precursors of adenoma and cancer.

BACKGROUND: Aberrant crypt foci of the colon are possible precursors of adenoma and cancer, but these lesions have been studied mainly in surgical specimens from patients who already had colon cancer. METHODS: Using magnifying endoscopy, we studied the prevalence, number, size, and dysplastic features of aberrant crypt foci and their distribution according to age in 171 normal subjects, 131 patients with adenoma, and 48 patients with colorectal cancer. We also prospectively examined the prevalence of aberrant crypt foci in 11 subjects (4 normal subjects, 6 with adenoma, and 1 with cancer) before and after the administration of 100 mg of sulindac three times a day for 8 to 12 months and compared the results with those in 9 untreated subjects (4 normal subjects and 5 with adenoma). All 20 subjects had aberrant crypt foci at base line. RESULTS: We identified 3155 aberrant crypt foci, 161 of which were dysplastic; the prevalence and number increased with age. There were significant (P<0.001) correlations between the number of aberrant crypt foci, the presence of dysplastic foci, the size of the foci, and the number of adenomas. After sulindac therapy, the number of foci decreased, disappearing in 7 of 11 subjects. In the untreated control group, the number of foci was unchanged in eight subjects and slightly increased in one (P<0.001 for the difference between the groups). CONCLUSIONS: Aberrant crypt foci, particularly those that are large and have dysplastic features, may be precursors of adenoma and cancer.

Adenoma↗

Identification of a novel human homolog of the Drosophila dlg, P-dlg, specifically expressed in the gland tissues and interacting with p55.

We have identified a novel human homolog of the Drosophila dlg tumor suppressor gene, termed P-dlg, which has been mapped at chromosome 10q23. Unlike other human dlg homologs, P-dlg is expressed in placenta and various gland tissues but not in brain. The P-dlg protein is localized at the plasma membrane and cytoplasm, and it is expressed in the gland epithelial cells in normal prostate tissue but not in prostate cancer cell lines. Furthermore, we identified interaction between P-dlg and p55 palmitoylated membrane protein by yeast two-hybrid screening. These findings suggest that P-dlg forms a complex with p55 at the plasma membrane and plays roles in maintaining the structure of epithelial cells and transmitting extracellular signals to the membrane and cytoskeleton, which may negatively regulate cell proliferation.

Amino Acid Sequence↗