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H Aoyama

Publications and source records attributed to H Aoyama.

At least 73 records · Page 4Linked to original sources
PubMed1999

Three-dimensional movement of a liver tumor detected by high-speed magnetic resonance imaging.

OBJECTIVE: Three-dimensional (3D) movement of a spherical liver tumor during respiration was investigated with magnetic resonance imaging (MRI) using a high-speed sequence. METHODS: A marker was placed on the surface of the patient as a reference of distance. Repetition time (TR) was 7.7 ms, echo time (TE) was 4.2 ms, flip angle was 20 degrees, section thickness was 8 mm, and a 256 x 128 matrix was used. The acquisition time was 1.0 s followed by an interval of 0.5 s. The 20 tumor contours extracted during 30 s were superimposed on sagittal and coronal MR images. RESULTS: The maximum value of tumor edge location was 3.9 cm in the cranio-caudal direction, 2.3 cm in the ventro-dorsal direction, and 3.1 cm in the lateral direction. The mean length of tumor displacement observed was 2.1 cm in the cranio-caudal direction, 0.8 cm in the ventro-dorsal and 0.9 cm in the left-right direction, respectively. The locus of the center of the tumor contour in the sagittal cross section was inclined at 23 degrees and in the coronal cross section was inclined at 18 degrees to the cranio-caudal axis of body. CONCLUSION: In conclusion, 3D movement of a spherical liver tumor was detected using rapid MRI sequential examinations. Magnetic resonance imaging has a potential to improve the accuracy of the planning target volume of a liver tumor.

Humans↗
PubMed1999

Determination of linezolid in plasma by reversed-phase high-performance liquid chromatography.

An HPLC-UV method was developed for assay of linezolid in dog, rat, mouse, and rabbit plasma. Linezolid and the internal standard were extracted on a solid phase cartridge (SPE) and separated on a reversed-phase column (C8, 4.6x150 mm, 5 microm) with 20% acetonitrile in water as mobile phase. The SPE quantitatively recovered linezolid and the internal standard from plasma samples. The chromatographic peak height ratio or peak area ratio based on UV absorbency at 251 nm was used for quantitative analysis. The assay procedures were simple and the assay was specific and had adequate precision and accuracy. Calibration standards with concentrations over the range of 0.01 20 microg/ml were validated for routine sample analysis to support the pharmacokinetic and toxicology studies with linezolid in dog, rat, mouse, and rabbit. Analysis of quality control samples showed the coefficients of variation were usually <10% and the measured and theoretical concentrations differed by <10% in most assays. Linezolid in the plasma samples was stable when stored at below -20 degrees C for at least 63 days, at room temperature (22-23 degrees C) for up to 24 h, and after three freeze-thaw cycles. This HPLC method has been successfully used in multiple laboratories to assay plasma samples from pharmacokinetic and toxicology studies with linezolid in the animal species.

Acetamides↗
PubMed1999

A phase I/II study of continuous intra-arterial chemotherapy using an implantable reservoir for the treatment of liver metastases from breast cancer: a Japan Clinical Oncology Group (JCOG) study 9113. JCOG Breast Cancer Study Group.

BACKGROUND: Liver metastasis from breast cancer has a poor prognosis. While there are some reports of good response rates of hepatic metastasis from breast cancer by hepatic intra-arterial infusion chemotherapy, no phase I study including pharmacokinetic analysis has been reported. We performed a phase I/II study of intra-arterial infusion chemotherapy using adriamycin and 5-fluorouracil to find the maximum tolerated dose and response rate in patients with advanced or recurrent breast cancer. METHODS: A hepatic arterial catheter with an access port was inserted into the proper hepatic artery. Patients received 30 mg/m2 adriamycin on days 1 and 8 and 100 mg/m2 5-fluorouracil at level 1, 200 mg/m2 at level 2,300 mg/m2 at level 3 and 400 mg/m2 at level 4 continuously from day 1 through day 14 every 28 days. At least two cycles were required before evaluation. Twenty-eight patients were entered into this study and 26 patients were evaluable. Seventeen patients had hepatic metastasis only, although nine patients had additional metastasis to other sites. RESULTS: Dose-limiting toxicity of thrombocytopenia and neurotoxicity occurred at level 4. Leukocytopenia (ECOG grade 3-4) was observed in five (19%), thrombocytopenia in three (12%) and anemia in two (8%) patients. There were 11 catheter-related complications which were not dose dependent. Seven out of 13 evaluable patients (54%) responded at level 3. The median duration of response was 5.8 months (range, 1-23+) and median survival was 25.3 months (range, 6.2-54.7+). CONCLUSION: Hepatic arterial infusion therapy appears to be safe and effective but catheter-related complications must be overcome before starting a phase III trial.

Adolescent↗
PubMed1999

Nummular eczema: An addition of senile xerosis and unique cutaneous reactivities to environmental aeroallergens.

BACKGROUND: The pathogenesis of nummular eczema (NE) is still unknown. It often develops on the lower legs of elderly individuals with xerotic changes during the winter months. Such winter exacerbation is also observed in atopic dermatitis, in which there is a high incidence of cutaneous immune reactivities against environmental aeroallergens. OBJECTIVE: Because of the total lack of information about skin reactivities in NE patients, we performed immunological as well as functional studies in their uninvolved skin. METHOD: Prick tests and chamber scarification patch tests for representative aeroallergens were conducted on the flexor surface of the forearm in 26 NE patients, in 21 age-matched elderly persons without NE and in 43 healthy young controls. RESULTS: We found that the elderly subjects, regardless of their background, showed a significantly higher immediate skin reactivity to Candida albicans than the young controls. In contrast, patch testing revealed that, unlike the age-matched elderly subjects who showed a decrease in incidence of positive patch test reactions, the NE patients retained delayed contact sensitivity at a level comparable to that of the young healthy controls. They showed a significantly higher percentage of positive patch test reactions to Dermatophagoides farinae allergen (46%) and house dust allergen (35%) than the age-matched controls. Moreover, they also showed a significantly higher percentage of delayed hypersensitive reactions to C. albicans allergen (85%) than the age-matched controls (48%). Noninvasive functional assessment of the stratum corneum (SC) in unaffected skin areas of the lower legs in 8 NE patients demonstrated that, though the water barrier function of the SC was comparable to that of the age-matched controls, they showed a significantly lower hydration state of the SC than the age-matched controls. CONCLUSION: The xerotic skin of elderly individuals facilitates the development of cracking and fissuring of the skin surface in dry and cold winter. Such damage in the SC is sometimes aggravated by inadvertent scratching due to pruritus, allowing skin permeation of various environmental allergens. They may induce eczematous changes in those with preserved adequate delayed hypersensitivity despite their advanced age.

Aged↗
PubMed1999

Medical students' perception of inpatients' anxiety, self-esteem, purpose-in-life and health locus of control as compared with nursing practitioners'.

Medical students (fourth-year: n = 67; fifth-year: n = 63) estimated inpatients' feelings of anxiety, self-esteem, purpose-in-life, and multidimensional health locus of control. Their ratings were compared both with the ratings given by the 121 inpatients themselves and with those given by nursing practitioners (nurses and nursing students). Findings showed that the medical students overestimated inpatients' anxiety, while they underestimated the inpatients' purpose-in-life and internal health locus of control. Hence they underestimated, as did the nursing practitioners, the inpatients' positive emotional states and their positive attitude toward their own lives. Fifth-year medical students, with clinical experience, rated the inpatients' score of chance health locus of control higher than did the fourth-year medical students, who had no clinical experience. These findings indicate that medical students, like nursing practitioners, are inclined to pay more attention to inpatients' weaknesses than to their strengths.

Analysis of Variance↗
PubMed1999

[Weekly hepatic arterial infusion of high dose 5-fluorouracil for liver metastasis from colorectal cancer].

A weekly infusion of high dose 5-fluorouracil by way of the hepatic artery has been performed in 23 cases with synchronous metastasis from colorectal cancer since 1993. The prognosis in these cases was compared with 94 cases treated without infusion chemotherapy in 94 cases before 1992. The overall one-year and three-year survival rate was 64.8% and 30.2%, respectively, in cases with infusion chemotherapy. The one-year and three-year survival rate was 42.8% and 18.6%, respectively, in cases without infusion chemotherapy. Overall survival rate was significantly different between cases with and without infusion chemotherapy (p < 0.05). In conclusion, weekly infusion chemotherapy resulted in a better survival rate than without infusion chemotherapy.

Antimetabolites, Antineoplastic↗
PubMed1999

Fate maps of the primitive streak in chick and quail embryo: ingression timing of progenitor cells of each rostro-caudal axial level of somites.

Developmental fates of cells emigrating from the primitive streak were traced by a fluorescent dye Dil both in chick and in quail embryos from the fully grown streak stage to 12-somite stage, focusing on the development of mesoderm and especially on the timing of ingression of each level of somitic mesoderm. The fate maps of the chick and quail streak were alike, although the chick streak was longer at all stages examined. The anterior part of the primitive streak predominantly produced somites. The thoracic and the lumbar somites were shown to begin to ingress at the 5 somite-stage and 10 somite-stage in a chick embryo, and 6 somite-stage and 9 somite-stage in a quail embryo, respectively. The posterior part of the streak served mainly as the origin of more lateral or extra embryonic mesoderm. As development proceeded, the fate of the posterior part of the streak changed from the lateral plate mesoderm to the tail bud mesoderm and then to extra embryonic, allantois mesoderm. The fate map of the primitive streak in chick and quail embryo presented here will serve as basic data for studies on mesoderm development with embryo manipulation, especially for transplantation experiments between chick and quail embryos.

Animals↗
PubMed1998

Soybean seed acid phosphatases: unusual optimum temperature and thermal stability studies.

In contrast to other acid phosphatases, four cytoplasmic isoforms (AP1, AP2, AP3A, and AP3B) purified from mature soybean seeds presented high activities at temperatures above 80 degrees C, when p-nitrophenylphosphate (p-NPP) was utilized as substrate. However, with tyrosine phosphate and inorganic pyrophosphate as substrates, maximum activities were observed at temperature of 60 degrees C during 10 min reaction. In the absence of substrate, enzymes lost only 20% activity after 60 min at 60 degrees C; the isoforms AP3A and AP3B retained 30% of activity at 70 degrees C after 60 min and all the isoforms were inactivated at 80 degrees C, after 5 min. Thermal inactivation studies indicated that the soybean enzymes showed different temperature dependences in relation to most plant acid phosphatases. A best protective effect was observed when the isoforms were preincubated, at 70 degrees C, with phosphate (10 mM) and p-nitrophenol (10 mM) which indicates that the enzyme inactivation was prevented only in the presence of both reaction products.

Acid Phosphatase↗
PubMed1998

Virtual pancreatoscopy of mucin-producing pancreatic tumors.

We used computer-based virtual endoscopy techniques as a novel approach to clarify the three-dimensional (3D) surgical anatomy of the pancreas and of mucin-producing pancreatic tumors. Thirteen cases (18 lesions) of mucin-producing pancreatic tumors were investigated by virtual pancreatoscopy. Virtual endoscopic images were generated with virtual endoscopy software application on UNIX workstations. We created surface-rendered virtual endoscopic images derived from a computer reconstruction of the cross-sectional magnetic resonance imaging data. Virtual endoscopy could visualize the surfaces of the pancreatic duct and the bile duct, and also demonstrated all cystic tumors. The surfaces of malignant mucin-producing pancreatic tumors were illustrated as being more irregular than those of benign lesions. The virtual endoscopic technique could demonstrate not only a surface-rendered endoscopic image of the tumors but also a 3D reconstructed image of the pancreas. The relationship to anatomic structures located outside the surfaces is continuously maintained and displayed at the same time. Virtual pancreatoscopy was useful for surgical planning of minimally invasive resection of the pancreas.

Adenocarcinoma, Mucinous↗
PubMed1998

Pathologically-proven intracranial germinoma treated with radiation therapy.

BACKGROUND AND PURPOSE: A retrospective multi-institutional study was conducted to survey what percentage of intracranial germinomas were treated with pathological confirmation before radiotherapy and to investigate the influence of field selection on outcome. MATERIALS AND METHODS: Thirty-seven percent of patients (41 of 110 patients) were pathologically confirmed before radiotherapy during the past 16 years at eight institutions in Northern Japanese prefectures. Pathological confirmation was obtained in 26, 37 and 53% of cases during 1978-1983, 1984-1989 and 1990-1994, respectively. All 110 patients were examined using computed tomography (CT) scans. Among the 41 patients with pathologically confirmed germinoma, radiation fields were craniospinal in 23 patients, whole-brain in 10 patients and local without ventricle inclusion in eight patients. RESULTS: For the 41 patients with pathologically confirmed germinoma, the actuarial and cause-specific survival rates were 91/94% at 5 years and 87/90% at 10 years, respectively. The relapse-free survival rate at 10 years was 90. 76 and 22% for the craniospinal field, whole-brain field and local field without ventricle inclusion, respectively. CONCLUSION: Pathological confirmation was obtained in only 37% of CT-scan era cases, although the confirmations were more commonly carried out later in the study period. Limited local irradiation alone without ventricle inclusion cannot be recommended for localized tumors even with the help of CT scanning.

Adolescent↗
PubMed1998

Retrospective multi-institutional study of radiotherapy for intracranial non-germinomatous germ cell tumors.

The treatment outcome of 24 patients with pathologically-proven non-germinomatous germ cell tumor was retrospectively investigated to determine the effectiveness of radiotherapy. The patients were divided into three groups as follows: group 1, five patients with mature teratoma with or without germinoma; group 2, six patients with immature teratoma with or without germinoma; group 3, 13 patients with other highly malignant tumors. The overall actuarial survival and relapse-free rates at 5 years were 82% and 59%, respectively, with a median follow-up period of 62 months. The actuarial relapse-free rate at 5 years was 100% for group 1, 63% for group 2 and 44% for group 3. There was no difference in the relapse-free rates between total resection and partial resection. Usage of chemotherapy was adversely related to survival probably due to selection bias. No local failure was observed with 10 Gy or more for group 1,40 Gy or more for group 2 and 54 Gy or more for group 3. In groups 1 and 2, there was no spinal relapses without craniospinal irradiation. In group 3, three of eight patients who did not receive craniospinal irradiation and none of five patients who received craniospinal irradiation experienced spinal relapse. In conclusion, highly malignant GCTs show a high incidence of spinal metastasis and craniospinal irradiation may reduce the risk of spinal metastasis. Radiation dose and volume are to be determined according to the histopathological aggressiveness.

Adolescent↗
PubMed1998

Cyclophosphamide, adriamycin, 5-fluorouracil and high-dose toremifene for patients with advanced/recurrent breast cancer. The Japan Toremifene Cooperative Study Group.

BACKGROUND: Multi-combination chemotherapy consisting of anthracyclines has been effective but has not invariably prolonged the survival period in advanced/recurrent breast cancer. The possibility has been discussed that chemoendocrine therapy combined with endocrine agents is more effective. METHODS: In order to evaluate the toxicity and efficacy of a new endocrine therapy for advanced/recurrent breast cancer, we ran a pilot study during the period from July 1994 to July 1996. RESULTS: Twenty-two patients with advanced/recurrent breast cancer were treated with chemoendocrine therapy consisting of cyclophosphamide (100 mg/body) p.o. daily for 14 days, with adriamycin (40 mg/m2) i.v. and 5-fluorouracil (500 mg/body) i.v. on day 1 (repeated every 3 weeks for 9 weeks) (CAF therapy), and high-dose toremifene (120 mg/body) p.o. daily. Of 20 evaluable patients, two showed complete response (10%), eight partial response (40%), six no change (30%) and four progressive disease (20%). The overall response rate was 50%, and the median duration of response was 69.5 days (28-133+ days). The major toxicities were drug-induced alopecia, gastrointestinal toxicity and hematological toxicity, but these were clinically well tolerated. No serious cardiac, liver or renal symptom was seen. CONCLUSIONS: Based on these results, we consider the addition of high-dose toremifene to the CAF therapy to be useful in the treatment of advanced and recurrent breast cancer.

Adult↗
PubMed1998

Dermomyotomal origin of the ribs as revealed by extirpation and transplantation experiments in chick and quail embryos.

To elucidate role of the dermomyotome in the formation of the axial skeleton, we performed extirpation and transplantation experiments on the dermomyotomes in chick and quail embryos. When the thoracic dermomyotomes of chick embryos were removed, the intercostal muscles and the distal ribs were deficient, while the proximal ribs were more or less normal. Quail tissues including the dermomyotome, the ectoderm and the medial edge of lateral plate, were transplanted to replace chick dermomyotomes. In these chimeras, the ribs, which would be deficient without the back-transplantation, were recovered. The cells of the recovered part of the ribs as well as the intercostal muscles were derived from the quail transplants. These findings suggest that the distal rib originated from the dermomyotomes and not the sclerotome as previously believed. To localize the origin of the distal rib further, we removed restricted regions of the dermomyotomes along the mediolateral and the rostrocaudal axis. The more lateral the part of the dermomyotomes that we removed, the more distal the part of the ribs affected. On the contrary, when the rostral and caudal edges of the dermomyotomes were removed, only the vertebral ribs showed extensive deficiencies while removal of the middle part between the edges caused less deficiency. The sternal ribs were not deficient in either case, but were extensively affected when the entire lateral edge of dermomyotomes was included in the region removed. We conclude that the lateral edges of the dermomyotomes are the primordia of the sternal ribs, and the rostral and/or caudal edges of the medial part of dermomyotomes are the primordia of the distal part and not of the proximal part of the vertebral ribs.

Animals↗
PubMed1998

Nursing practitioners' perception of inpatients' anxiety, self-esteem, purpose-in-life and health locus of control.

This study explored how nursing practitioners perceived inpatients' anxiety, self-esteem, purpose-in-life and multidimensional health locus of control. Seventy-three nurses, 60 third-year and 70 first-year nursing students, and 61 control students not majoring in nursing science estimated how inpatients rated these four psychological states. Their ratings were compared with those given by 121 inpatients. Findings showed that the nursing practitioners, as well as the control participants, overestimated inpatients' anxiety, while they underestimated their self-esteem and purpose-in-life. The inpatients' scores for internal locus of control were greater than their scores for the two types of external locus of control (powerful others and chance), and were also greater than the scores given by the nursing practitioners in estimating the patients' perception of internal locus of control. The findings indicate that inpatients have a more positive attitude toward themselves and their own lives, and hence much better mental health, than the nursing practitioners estimate they do.

Adult↗
PubMed1998

[Early phase II study of TAT-59 in patients with advanced or recurrent breast cancer--a multicenter dose finding study].

A dose finding early phase II study of TAT-59, a new triphenylethylene derivative, was performed in patients with advanced or recurrent breast cancer. TAT-59 was given orally for over 8 weeks at a daily dose of 10 mg, 20 mg or 40 mg/day. Thirty-six, 38 and 35 patients were eligible in the group treated with 10, 20 and 40 mg of TAT-59, respectively. The proportion of patients obtaining a complete or partial response with 10 mg/day, 20 mg/day and 40 mg/day of TAT-59 was 28.6% (10/35), 28.6% (10/35) and 25.8% (8/31) in the evaluable cases, respectively. The median duration of initial response with TAT-59 was 38.5 days, 26.5 days and 25.6 days, respectively. The frequent adverse reactions observed in all dosing groups included hot flashes, anorexia, nausea and vomiting, sweating, and abnormal values in liver function tests. In these adverse reactions, the incidence of hot flashes, which might be caused by the pharmacologic function of TAT-59 was 0.0% (0 of 35), 2.9% (1 of 35) and 10.0% (3 of 30) in the evaluable cases receiving 10 mg, 20 mg and 40 mg of TAT-59, respectively. In conclusion, it was recommended that the optimal dose in terms of efficacy and adverse reactions should be 20 mg/day.

Adult↗
PubMed1998

[Hepatic arterial infusion chemotherapy (HAI) for advanced hepatocellular carcinoma inefficacious with transcatheter arterial embolization (TAE)].

For 6 patients with advanced hepatocellular carcinoma (HCC) in whom TAE was inefficacious, we tried hepatic arterial infusion chemotherapy. 5-FU 500 mg/day + CDDP 10 mg/day was administered during 5 days. The AFP level was decreased for 4 patients, and 2 patients showed a partial response in CT image. These 2 patients have been alive over 22 and 18 months, respectively. These results suggest that 5-FU + CDDP HAI might be a useful treatment of HCC inefficacious with TAE.

Aged↗
PubMed1998

[An early phase II clinical study of S-1 in patients with breast cancer. S-1 Cooperative Study Group (Breast Cancer Working Group)].

An early phase II clinical study of S-1 in patients with advanced or recurrent breast cancer was undertaken by a cooperative study group (Breast Cancer Working Group) of 14 institutes in Japan. S-1 was administered twice daily at 75 or 50 mg (dose FT)/body for 28 consecutive days with 14 days rest (one course). Twenty-eight patients were enrolled, 27 were eligible for the study, and 25 were evaluable for efficacy. Four complete responses and seven partial responses were obtained, and the response rate was 40.7% (11/27) [ninety percent confidence interval for this response was 26.7-56.4%]. The major adverse reactions observed were myelosuppression represented by leukopenia 44.4% (12/27), neutropenia 40.7% (11/27), RBC decreased 37.0% (10/27), hemoglobin decreased 29.6% (8/27), anorexia 55.6% (15/27), nausea/vomiting 48.1% (13/27), and fatigue 33.3% (13/27). The results suggested that the efficacy and safety of S-1 were effective against advanced or recurrent breast cancer. The objective of study judged should be investigated in a late phase II clinical study.

Adult↗