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Biomedical subjects

H Ikeda

Publications and source records attributed to H Ikeda.

At least 181 records · Page 10Linked to original sources
PubMed2001

Morphologic and molecular analysis of estrogen-induced pituitary tumorigenesis in targeted disruption of transforming growth factor-beta receptor type II and/or p27 mice.

The critical genes and products involved in estrogen-induced tumorigenesis of the pituitary gland were investigated in heterozygous transforming growth factor-beta (TGF-beta) receptor type II and p27 knockout mouse models. Tgfbr2(+/-), p27(+/-); Tgfbr2(+/-), and p27(+/-) mice and C57BL/6J wild-type mice received sc implantation of estrogen or placebo pellets for 16 or 25 wk, after which the mice were sacrificed and their pituitary glands removed for examination. The bromodeoxyuridine labeling indexes in tissue from both the anterior and intermediate pituitary lobes from p27 (+/-) and Tgfbr2(+/-); p27(+/-) mice were significantly higher than those from wild-type and Tgfbr2(+/-) mice after treatment with estrogen for 16 wk. Pituitary tumorigenesis was significantly accelerated in Tgfbr2(+/-), p27(+/-), and Tgfbr2(+/-); p27(+/-) mice compared with wild-type mice after treatment with estrogen for 16 wk. Pituitary tumorigenesis was not accelerated in Tgfbr2(+/-); p27(+/-) mice compared with Tgfbr2(+/-) or p27(+/-) mice. Expression of TGF-beta receptor type II mRNA was lower in the pituitary gland of Tgfbr2(+/-) mice than in wild-type mice before estrogen treatment and was significantly reduced after treatment. Pituitary tumorigenesis is accelerated in mice with severe TGF-beta resistance, and greatly accelerated in mice with TGF-beta resistance combined with decreased p27 expression compared with wild-type mice. Both the TGF-beta receptor type II gene and p27 gene and their products are involved in estrogen-induced tumorigenesis.

Animals↗
PubMed2001

Comparison of the effects of different antiviral treatments on the antioxidant systems of stroma-free hemoglobin.

The effect of virus inactivation by 1,9-dimethylmethylene blue (DMMB) phototreatment, methylene blue (MB) phototreatment or heat on the activities of antioxidant systems of stroma-free hemoglobin (SFH) was studied. DMMB photoinactivated human immunodeficiency virus by > 3.69 log10 under conditions that inactivated 3.33 log10 of vesicular stomatitis virus (VSV). Under conditions which inactivated VSV by 6.10 log10 (1.37 J/cm2 irradiation and 2 microM DMMB), there was little change in the methemoglobin (Met-Hb) formation, concentration of reduced glutathione (GSH), or superoxide dismutase (SOD), catalase (CAT) or glutathione peroxidase (GPX) activities. However, the activity of glutathione reductase (GR) was decreased by 77%. Under conditions that inactivated VSV by 5.69 log10 (1.37 J/cm2 irradiation and 24 microM MB) there was little effect of MB phototreatment on SOD, CAT, GPX and GSH activities. However, GR activity was decreased by 74% and Met-Hb content reached 3.98%. Under conditions that inactivated VSV by more than 6.20 log10 (60 degrees C for 2 min), virucidal heat treatment resulted in 27% Met-Hb formation and decreased GPX activity by 43%. No significant decline in SOD, CAT or GR activities or GSH concentration was observed. These results suggest that, compared with heat treatment and MB phototreatment, virucidal DMMB treatment preserves not only the oxidative state of hemoglobin but also the antioxidant systems against superoxide and hydrogen peroxide, although the reduced GR activity may limit the quenching capacity of antioxidants in DMMB-treated SFH.

Antioxidants↗
PubMed2001

Sampling methods and residential factors affecting formaldehyde concentration in indoor air.

Formaldehyde (HCHO) is the most serious residential pollutant. In order to evaluate residential HCHO levels, two sampling methods have been recommended; one is a 30 minute sampling in a closed room, and the other is a 24 hour sampling with an ordinary lifestyle routine. The aim of this report was to clarify the difference between the HCHO levels obtained by the two sampling methods. Residential air in 58 rooms was sampled for 30 minutes by an active sampling method more than 5 hours after residents closed windows, and by a passive sampling method for 24 hours with an ordinary lifestyle routine. The HCHO concentration with the 30 minute sampling was 0.118+/-0.065 ppm (range: 0.034-0.295 ppm) and 36 rooms (62%) exceeded the Japanese guideline value of 0.08 ppm, while 5% were higher than 0.25 ppm. The HCHO concentration with the 24 hours sampling was 0.053+/-0.039 ppm (range: 0.02-0.167 ppm) and only 13 rooms (22%) exceeded 0.08 ppm. The relationship between the concentrations obtained by the two methods was linear. However, the level with the 24 hour sampling significantly reduced with prolonged window opening time, meaning that occupants made an effort to reduce the usual exposure to about 40% of the exposure in a closed room by opening windows in order to escape from irritation. Since major adverse effects of HCHO are irritation and sensitization, the occasional peak concentration must be focused. In order to evaluate residential HCHO levels, measurement in a closed room is recommended even if people are living there.

Air Conditioning↗
PubMed2001

Idiopathic giant cell granulomatous hypophysitis with hypopituitarism, right abducens nerve paresis and masked diabetes insipidus.

A 38-year-old man presented with headache, fever, and double vision associated with right abducens nerve paresis. He had neither nuchal rigidity nor visual field defect. Laboratory data revealed elevated erythrocyte sedimentation rate (ESR), eosinophilia, and lymphocytic pleocytosis in the cerebrospinal fluid (CSF). Provocation tests of pituitary hormones showed partial hypopituitarism. Magnetic resonance imaging (MRI) revealed swelling of the hypophysis and a mass lesion expanding into the right cavernous sinus. The supplement dose of dexamethasone for hypothalamic hypocortisolism manifested diabetes insipidus. Biopsy, carried out through the transsphenoidal approach, revealed giant cell granuloma. Systemic granulomatous diseases were ruled out, and the lesion was considered to be idiopathic giant cell granulomatous hypophysitis. Right abducens nerve paresis, diabetes insipidus and dysfunction of the anterior lobe were amended by the treatment with prednisolone for 4 months, and findings of the pituitary gland and stalk were normalized. The present case shows that glucocorticoid has an effect on amendment of idiopathic giant cell granulomatous hypophysitis.

Abducens Nerve Diseases↗
PubMed2001

Neuroradiological features of intraosseous cavernous hemangioma--case report.

A 40-year-old man presented to our hospital because of a painless lump on his right forehead. Radiography showed a radiolucent defect in the frontal bone. Bone window computed tomography demonstrated a lucent mass which expanded externally from the diploë destroying and passing through the outer plate. T1-weighted magnetic resonance imaging revealed the lesion as non-homogeneously isointense, and T2-weighted imaging as non-homogeneously hyperintense. The lesion was enhanced non-homogeneously after contrast administration. The lesion was subtotally removed. Histological examination suggested cavernous hemangioma. Preoperative examinations could not provide a definitive diagnosis, which was established by the operative finding. Because of the difficulty of diagnosis in the early stage, surgical treatment in the early stage is recommended for total removal and definitive diagnosis of intraosseous tumor.

Adult↗
PubMed2001

Efficacy of navigation in skull base surgery using composite computer graphics of magnetic resonance and computed tomography images.

The efficacy of a neurosurgical navigation system using three-dimensional composite computer graphics (CGs) of magnetic resonance (MR) and computed tomography (CT) images was evaluated in skull base surgery. Three-point transformation was used for integration of MR and CT images. MR and CT image data were obtained with three skin markers placed on the patient's scalp. Volume-rendering manipulations of the data produced three-dimensional CGs of the scalp, brain, and lesions from the MR images, and the scalp and skull from the CT. Composite CGs of the scalp, skull, brain, and lesion were created by registering the three markers on the three-dimensional rendered scalp images obtained from MR imaging and CT in the system. This system was used for 14 patients with skull base lesions. Three-point transformation using three-dimensional CGs was easily performed for multimodal registration. Simulation of surgical procedures on composite CGs aided in comprehension of the skull base anatomy and selection of the optimal approaches. Intraoperative navigation aided in determination of actual spatial position in the skull base and the optimal trajectory to the tumor during surgical procedures.

Computer Graphics↗
PubMed2001

Transsphenoidal surgery and adjuvant gamma knife treatment for growth hormone-secreting pituitary adenoma.

OBJECT: The results of combined transsphenoidal surgery and adjuvant gamma knife surgery (GKS) for growth hormone (GH)-secreting adenoma were investigated using biochemical cure criteria for surgery and biological cure criteria for adjuvant GKS. METHODS: Ninety patients (42 male and 48 female patients), ranging from 11 to 75 years of age, underwent transsphenoidal surgery for GH-secreting pituitary adenoma. Preoperative and postoperative GH and insulin-like growth factor-I levels were measured, as was the postoperative GH level after the oral glucose tolerance test. Tumor size, cavernous sinus (CS) invasion, and residual tumor were evaluated using magnetic resonance (MR) imaging. Transsphenoidal microsurgery was performed, followed by adjuvant GKS when there was persistent biochemical evidence of GH hypersecretion with residual tumor detectable in the CS on MR imaging. Patients in whom GKS was contraindicated were treated with conventional radiotherapy or by medical means. CONCLUSIONS: The overall surgical cure rate was 57% based on recently accepted biochemical cure criteria. Patients with no CS invasion achieved a 100% cure rate, whereas patients with CS invasion achieved an 82% cure rate (14 of 17 patients) after adjuvant GKS. The combination of transsphenoidal microsurgery and adjuvant GKS is the optimal therapy for patients with GH-secreting adenoma.

Adenoma↗
PubMed2001

Sodium 1-monolinolenin isolated from Italian ryegrass (Lolium multiflorum Lam) induces apoptosis in human lymphoid leukemia Molt 4B cells.

The exposure of human lymphoid leukemia Molt 4B cells to sodium 1-monolinolenin (SML) which was isolated from the leaves of Italian ryegrass (Lolium multiflorum Lam) and identified by Mass, and (1)H- and (13)C-NMR, led to both growth inhibition and induction of programmed cell death (apoptosis). Morphological change showing apoptotic bodies was observed in the Molt 4B cells treated with SML. The fragmentation by SML of DNA to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, was observed to be both concentration- and time-dependent. These findings suggest that growth inhibition by SML of Molt 4B cells results from the induction of apoptosis in the cells.

Antineoplastic Agents, Phytogenic↗
PubMed2001

Effects of recombinant human endostatin on a human neuroblastoma xenograft.

New antitumor agents must be added to the current neuroblastoma treatment regimens to improve the clinical results. We investigated whether recombinant human endostatin (rhEndostatin), an antiangiogenic agent, is effective against human neuroblastoma in the human neuroblastoma xenograft model designated TNB9. When tumors on the back of nude mice grew to a weight of 90-95 mg, rhEndostatin 10 mg/kg/day was administered subcutaneously every day for 10 consecutive days. Mean relative tumor weight in mice administered rhEndostatin (n=5) was significantly less than that in controls (n=12) on days 2, 4, and 6 after the start of administration (p<0.01 on day 2, p<0.05 on days 4 and 6), and regression of tumor growth (TRW<1.0) was marked on day 2. The maximum inhibition rate (MIR) by rhEndostatin was 46.4%, indicating inefficacy, but it may not be appropriate to apply Battelle Columbus Laboratories criteria to this experimental model because rhEndostatin is a protein. After day 8, tumors in the experimental group increased in weight and were not statistically significantly different from those in controls. Recombinant human endostatin was used in tumors in the arterial system of the mouse in this experiment because eventually rhEndostatin, not recombinant mouse endostatin, may be used to treat advanced neuroblastoma in the clinical setting. The results show that there is little cross-reactivity of rhEndostatin with the human and mouse models and indicate that rhEndostatin could become an effective agent for the treatment of human neuroblastoma.

Animals↗
PubMed2001

Microvessel density predicts the radiosensitivity of metastatic head and neck squamous cell carcinoma in cervical lymph nodes.

Cervical lymph node metastasis is the most common recurrence pattern of head and neck squamous cell carcinoma (HNSCC), and it is usually treated with radiation therapy and/or neck dissection. There has long been a desire for markers useful in predicting radiosensitivity to enable assignment of patients with recurrent head and neck cancer to clinical trials to improve their survival rates and quality of life. A total of 43 cases of HNSCC treated with whole or elective neck irradiation (total dose, 26-70 Gy; median, 60 Gy) for recurrent metastatic SCC in neck lymph nodes after neck dissection between 1992 and 1999 were the subject of this study. The relationship between radiosensitivity and clinicopathological and histopathological factors, including the Ki-67-labeling index for cell proliferation, p53 immunoreactivity and microvessel density (MVD), in surgical neck lymph node specimens were investigated by univariate and multivariate analysis. Of the 43 patients, 31 had recurrent tumors in neck lymph nodes after radiotherapy. Univariate analysis revealed significant associations between radiosensitivity and both high grade of keratinization (p=0.033) and low MVD (p=0.004), and marginally significant associations between radiosensitivity and grade of differentiation of the cancer in the lymph nodes (p=0.070). Multivariate analysis showed that only MVD had predictive value (p=0.016). Tumors with a high MVD possessed a significantly better neck control rate than tumors with a low MVD (p=0.004) by Kaplan-Meier analysis. MVD can be used as a good predictive marker for radiosensitivity of metastatic HNSCCs in cervical lymph nodes after neck dissection.

Aged↗
PubMed2001

[A case of leiomyosarcoma of the renal vein].

A 54-year-old woman presented with a 6-month history of left back pain. She had undergone left mastectomy for breast cancer in 1993 and hysterectomy for cervical cancer in 1997. Excretory urography showed no abnormality in the left collecting system, but right hydronephrosis caused by a midureteral stone. She was treated by transurethral ureterolithotripsy first. Computerized tomography showed a 4 x 3 cm. mass enhanced slightly by contrast medium at the left renal hilus. The tumor was bordered laterally by the left kidney and posteriorly by the left renal vein which appeared normal on magnetic resonance imaging. Selective left renal angiography revealed no abnormality. Radical en bloc excision of the tumor with the left kidney and adrenal gland was performed. Pathological examination showed a well differentiated leiomyosarcoma arising from the renal vein; the tumor cells stained positive for alpha-smooth muscle actin, vimentin and desmin and negative for S 100-protein. She was free of symptoms and there was no evidence of local recurrence or distant metastases 22 months postoperatively.

Female↗
PubMed2001

[The ratios of apoC-III/apoC-II in normal full-term maternal bloods and their umbilical cord bloods].

In this paper, serum concentrations of CII and CIII in MB(n = 12) represented 158% and 237% of those in 20 specimens of normolipidemic venous blood from healthy fasting non-pregnant females(Control), and the CIII/CII ratio of MB(mean +/- SD = 3.6 +/- 0.4) was significantly higher than that of the Control(2.38 +/- 0.42). While the difference between the serum CII level in MB and that of 14 specimens of postmenopausal patients lipid-matched to MB(postM HL) was not significant, serum CIII concentration of MB was significantly higher than that of postM HL. Furthermore, while the difference between the CIII level in apoB-containing lipoproteins of MB and that of postM HL was not significant, the CIII concentration in HDL(HDL-CIII) of MB was significantly higher than that of postM HL. It was suggested that the effect of pregnancy on apoC levels which change in parallel with the TGs level might reflect the selective increase in HDL-CIII concentration. In addition, the positive correlation between HDL-CIII and apoA-I concentration in MB was significant. However, it has been reported that the CIII/CII ratio of patients with type III hyperlipidemia treated with estrogens had been successively increased, and it was also reported that estrogens stimulate the synthesis of CIII in hepatocytes. It was thus suggested that maternal CIII as well as apoA-I might be selectively overproduced in the liver by stimulation from increased endogenous estrogens during normal pregnancy. On the contrary, the serum concentrations of CII and CIII in UCB represented 71% and 55% of those in Control, and the CIII/CII ratio of UCB(1.87 +/- 0.5) was significantly lower than those of the Control. In UCB, the positive correlation between CIII and TGs was weak(p < 0.1) and CII did not correlate with markedly decreased TGs. Serum concentrations of CII, CIII and the ratio of CIII/CII in MB did not correlate with those in UCB, respectively. Moreover, birth weight and birth length of neonates positively correlated with concentrations of TGs, CII and CIII in MB, respectively, but not in UCB. In conclusion, the increased maternal CIII/CII ratio is due to the estrogen-induced raise of CIII while the reduced neonatal CIII/CII is related to the decrease in TGs. These observations suggest that fetal TGs-rich lipoprotein metabolism is not affected by maternal lipoprotein metabolism.

Apolipoprotein C-II↗
PubMed2001

Variations of the basal vein: identification using three-dimensional CT angiography.

BACKGROUND AND PURPOSE: The basal vein of Rosenthal (BVR) presents with many variations because of its origin in the secondary longitudinal anastomoses between embryonic veins. The variations were evaluated by 3D CT angiography imaging. METHODS: Three-dimensional CT angiograms in the axial stereoscopic view and other directions constructed by the voxel transmission method and maximum intensity projection (MIP) images were obtained in 500 sides of 250 patients. RESULTS: The BVR flowed into the great vein of Galen in 87.8%, but the anastomoses between the first and second segments were not confirmed in 36.9% of this type. The first segments with hypoplastic or aplastic anastomoses flowed into the cavernous sinus or the sphenoparietal sinus. Therefore, typical BVRs with these anastomoses accounted only for 55.4% of all sides. More than one fourth of the typical type also entered the anterior veins such as the cavernous sinus. Drainage was to the lateral mesencephalic vein in 5.6%, peduncular vein in 1.6%, and lateral or medial tentorial sinus in 5.0%. CONCLUSION: Variations of the BVR can be classified on the basis of the five drainage pathways formed during the early embryonic stage. Three-dimensional CT angiography can show the stereoscopic anatomy and the main drainage routes, but not hypoplastic veins, which are only visible on MIP images.

Adult↗
PubMed2001

[Efficacy of docetaxel for anthracycline-resistant metastatic breast cancer].

From June 1997 through December 1999, we treated twenty-two metastatic breast cancer patients with Docetaxel (60 mg/m2 administered intravenously every four weeks). All patients had received prior chemotherapy including anthracycline, and also another agent such as MMC-VDS, HDMTX-5-FU or CPT-11. One CR, 5 PR, and 4 Long NC were achieved. Grade 3/4 leukocytopenia occurred in 16 patients. Using the Kaplan Meier method, the median time to progression was 179 days, and the median survival time was 369 days. No serious adverse effects were observed. In this study Docetaxel seems to have shown significant activity, even for poor candidates, with intensive prior therapy.

Alopecia↗
PubMed2001

A simple method for detection of gunshot residue particles from hands, hair, face, and clothing using scanning electron microscopy/wavelength dispersive X-ray (SEM/WDX).

We devised a simple and rapid method for detection of gunshot residue (GSR) particles, using scanning electron microscopy/wavelength dispersive X-ray (SEM/WDX) analysis. Experiments were done on samples containing GSR particles obtained from hands, hair, face, and clothing, using double-sided adhesive coated aluminum stubs (tape-lift method). SEM/WDX analyses for GSR were carried out in three steps: the first step was map analysis for barium (Ba) to search for GSR particles from lead styphnate primed ammunition, or tin (Sn) to search for GSR particles from mercury fulminate primed ammunition. The second step was determination of the location of GSR particles by X-ray imaging of Ba or Sn at a magnification of x 1000-2000 in the SEM, using data of map analysis, and the third step was identification of GSR particles, using WDX spectrometers. Analysis of samples from each primer of a stub took about 3 h. Practical applications were shown for utility of this method.

Cause of Death↗