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J Horiuchi

Publications and source records attributed to J Horiuchi.

At least 55 records · Page 3Linked to original sources
PubMed1994

[Evaluation of bone marrow by opposed phase T1-weighted images and enhanced MR imaging].

We investigated bone marrow in a control group, cases of aplastic anemia and post-irradiation patients by examining T1-weighted (T1WI), short TI inversion recovery (STIR), opposed phase T1WI (op-T1WI) and Gd-DTPA enhanced op-T1WI images obtained by 0.5T MRI. Bone marrow was classified into four types based on MR findings. Normal marrow showed low intensity on op-T1WI and STIR images without enhancement (I). Fatty marrow, which showed high intensity on T1WI and op-T1WI images was observed in aplastic anemia and post-irradiation patients (II). Hematopoietic marrow (III) showed low intensity on op-T1WI and enhanced, while active hematopoietic marrow (IV) revealed high intensity on both STIR and op-T1WI images and was enhanced following Gd-DTPA infusion. Aplastic anemia of moderate grade included types II, III and IV. Enhanced MR was needed to differentiate between types I and III since both types showed low intensity on op-T1WI images. Furthermore, type IV was considered as hyperplastic compared with type III. Enhanced MR and op-T1WI images were useful in evaluating hematopoiesis of bone marrow.

Adolescent↗
PubMed1994

[Z-100 as radiation mucositis protector in head and neck tumor management].

To study the radioprotective effect of Z-100 against mucositis, twenty-five patients with head and neck malignancies were received external irradiation of 30-61.2 Gy (mean 44.4 Gy) concurrent with Z-100 injection twice a week. Of these cases, an incidence of dysphagia was less than 20% and white coating mucositis below 50%. Frequency of radiation mucositis in these regions was reduced compared to our previous experiences; efficacy of 88%. This combined therapy seems to be a promising method.

Adult↗
PubMed1994

Descending pathways of powerful pressor response elicited by suprapontine cerebral ischemia in rabbits.

We determined the magnitude of the pressor and sympathoexcitatory responses elicited by suprapontine cerebral ischemia (SCI) and the descending pathways in the rostral medulla mediating them. The suprapontine structures of anesthetized and artificially ventilated rabbits were selectively exposed to cerebral ischemia, by combined occlusions of basilar and common carotid artery. SCI produced a pressor response of 78 +/- 9 (SE) mmHg and an increase in renal sympathetic nerve activity of 289 +/- 21% compared with preischemic levels. The magnitude of the pressor and sympathoexcitatory response to SCI was comparable to those in response to global cerebral ischemia. Microinjection of the neurotoxin kainic acid into the pressor sites of the rostral ventrolateral medulla significantly (P < 0.05) reduced the SCI pressor response to 34 +/- 11% of the prelesion control response. Chemical lesions of the pressor sites in the rostral medial and ventromedial medulla resulted in a significant decrease in the pressor response to SCI to 78 +/- 12% of the control response. These results indicate that the suprapontine structures play an important role in the generation of the powerful pressor response elicited by cerebral ischemia and that the pressor response to SCI is mediated by pressor neurons in the rostral medulla.

Animals↗
PubMed1993

[Efficacy of ultrasound detection of the oro- and hypopharyngeal carcinoma].

Sixteen histologically confirmed carcinomas of oro- and hypopharynx were examined by ultrasonography (US) from submental, submandibular, sub-auricular, and laterally cervical skin surface. Well-circumscribed hypoechoic tumors were demonstrated in twelve cases (75%). Nine of them had partial hypoechoic areas, such as "bull's eye pattern" or "pseudokidney sign". The remainder were one homogeneous hypoechoic mass and two inhomogeneous bulky tumors. In four negative studies, two were suspected too thin to be detected by US, and the other two could not be visualized by percutaneous scan because of their anatomical sites. The dimensions of demonstrated twelve tumors were measured three-dimensionally. The US information should be valuable for a prediction or an evaluation of the radiotherapy efficacy.

Adenocarcinoma↗
PubMed1992

Malignant melanomas of the oral cavity: heterogeneity of pathological and clinical features.

Data on 35 patients with oral malignant melanomas were pooled and the pathological features and the clinical course were examined in detail. Of these 35 cases, 27 (77.1%) showed a two-phase growth pattern, with both a vertical and a radial growth phase. Moreover, these 27 cases were classified into three subtypes according to gross features of the vertical growth phase; nodular, flat elevated and ulcerated types. Almost two-thirds of the cases were of the melanotic type. Malignant melanomas without a radial growth phase were found in 8 instances, all of which showed a nodular growth pattern, 1 being of melanotic type and 7 amelanotic. Mean latent insidious periods were evaluated for the cases with different growth phases. Cases with a radical growth phase exhibited the longest mean latent period (35.7 months), and a median survival time of 23.5 months. Cases without a radial growth phase showed a short mean latent period (2.1 months), and a median survival time of 7.5 months. The thickness of invasion ranged from 2 to 9 mm. Although 77.1% of the cases depicted similar pathological patterns to acral lentiginous melanomas of the skin, oral malignant melanomas demonstrated heterogeneity in morphological features, developmental process and biological behaviour. The histogenesis of oral melanomas is briefly discussed.

Adult↗
PubMed1992

Effects of hypoxia, hyperoxia and hypercapnia on graded cerebral ischemic responses in rabbits.

This study was designed to determine how several factors interact to modify the cerebral ischemic pressor response (CIR) in anesthetized rabbits. After the carotid sinus and aortic nerves were bilaterally sectioned, blood flow through the left internal carotid artery (ICF), which was surgically restricted as the sole route of blood supply to the brain, was reduced by a servo-controller during ventilation with room air, and 8% and 90% O2 and 2 and 5% CO2 gas mixtures. Blood flow (MBF), tissue PO2, PCO2, and interstitial pH were measured in the rostral ventrolateral medulla. Internal carotid arterial pressure, tissue PO2, and MBF decreased proportionately as ICF decreased in the range from 4 to 0 ml/min. Hypoxia significantly increased the rise in renal nerve activity (RNA) and CIR caused by cerebral ischemia, while hyperoxia significantly decreased them. Hypercapnia had almost no influence on the increases in RNA and mean arterial pressure produced by cerebral ischemia. CIR showed a much higher correlation with changes in tissue PO2 than with the other factors. We examined how these factors interact to modify CIR and found that central hypoxia is the main factor in producing CIR.

Animals↗
PubMed1992

[Multi-institutional trials of radiation and Furtulon combination therapy for malignant tumors].

The efficacy of the response and safety in combination therapy of radiation and furtulon, a derivative of fluoropyrimidine, for malignant tumors were tested on a multi-institutional basis. Patients in this study were given daily 800 mg of oral furtulon and also irradiations. Twenty-three out of 30 evaluable cases showed CR or PR response (response rate was 77%). The response rates of the cases classified into regions of primary sites were 67% of stomach (4/6), 57% of colorectum (4/7), 100% of breast (9/9), 67% of esophagus (4/6), 100% of ovary (1/1) and 100% of lung (1/1). Four out of 36 cases were not given the full scheduled treatments due to grade 3 side effects, consisting of one diarrhea case suspected due to furtulon side effect, 2 impaired general condition cases according to the progression of diseases, and one case showing radiation dermatitis, dysphagia due to radiation mucositis and leukocytopenia. These results show that the combination therapy of radiation and furtulon is an efficacious and safe modality for primary and metastatic tumors.

Administration, Oral↗
PubMed1991

[Measurement of urinary epidermal growth factor by radioimmunoassay and its application].

Epidermal growth factor (EGF), a polypeptide hormone originally discovered in the mouse submaxillary gland, stimulates growth in a variety of tissues in several species. This hormone has recently been identified in human urine. Herein, radioimmunoassay (RIA) for human EGF (hEGF) has been developed, using human recombinant EGF as reference standard and radioiodinated tracer and antibodies raised against hEGF. Its sensitivity was somewhat higher than that of RIAs reported formerly. This method had no cross reactivity with high molecular weight EGF. Urinary concentrations of hEGF in normal males and females were 30.2 +/- 13.0 ng/mg creatinine and 46.4 +/- 17.4 ng/mg creatinine, respectively. Urinary concentration of hEGF in patients with renal cancer was somewhat low. The patients with bladder cancer had lower urinary excretion of hEGF than normal adults (p less than 0.05). However, the role of hEGF in health and disease remains to be determined.

Adult↗
PubMed1991

Usefulness of 198Au grain implants in the treatment of oral and oropharyngeal cancer.

A series of 177 patients with squamous cell carcinoma of the oral cavity and oropharynx were treated with 198Au grain (gold grain) implants. Sites of the lesion included the tongue, mouth floor, buccal mucosa and oropharynx, especially the soft palate and faucial arch. Three-fourths of the patients were treated in combination with prior external beam irradiation. A permanent implant dose (total decay) of 80-90 Gy was given in the form of gold grains alone and in combination with an external dose of no more than 30 Gy, and 60-70 Gy, total decay, was given after an external dose greater than 30 Gy. The 2-year recurrence-free rate was 86.2% in the case of T1N0, 72.6% in T2N0 and 72.2% in T3N0. The difference in the results of implant therapy alone and combined therapy was not significant. Late complications were minimal after grain implantation alone, and when used in combination, less than 70 mCi of grain activity after a 40 Gy external dose did not seem to be a serious hazard with respect to bone damage except in the case of cancer of the mouth floor. Gold grain implants were useful and easily applied under local anesthesia to early or superficial lesions at sites where a rigid linear source could not be used. Exposure of the radiology staff was only 5-10 mrad in the case of the usual 10-15 (50-75 mCi) implant grains.

Brachytherapy↗
PubMed1991

Is big endothelin converted to endothelin-1 in circulating blood?

Although evidence has been accumulating to support an intracellular processing of big endothelin-1 (big ET-1) to ET-1, molecular conversion in the circulating blood remains to be elucidated. The present study was undertaken to investigate whether big ET-1 was converted to ET-1 in human blood. In the first experiment, normal serum with synthetic big ET-1 exogenously added or serum from patients with chronic renal failure was incubated in vitro at 37 degrees C for 1 h. In the second experiment, synthetic big ET-1 was incubated in the whole blood at 37 degrees C for 1 h. In the third experiment, synthetic big ET-1 was administered intravenously in anesthetized rat and a plasma sample was obtained before and after 15 min and 1 h. After respective incubation, molecular forms of ET were determined by a combination of reverse-phase high-performance liquid chromatography and radioimmunoassay. There was no significant conversion of big ET-1 to ET-1 in the serum obtained from normal and CRF patients. However, there was a slight but significant increase of ET-1 after incubation of big ET-1 in the whole blood or after administration of big ET-1 in anesthetized rat. The conversion in the whole blood was inhibited by 5 mM EDTA. These results suggest that circulating blood may not be a major site of molecular conversion from big ET-1 to ET-1, although conversion does occur in the circulation by blood cell-mediated process.

Animals↗
PubMed1991

Molecular form of immunoreactive endothelin in plasma and urine of normal subjects and patients with various disease states.

To elucidate the pathophysiologic significance of the family of endothelin (ET) peptides, we have investigated plasma and urinary immunoreactive (ir-) ET levels and its molecular forms in normal and pathological conditions. Plasma and urine ET were extracted with an Amprep C2 column. The molecular form of ET was determined by a combination of radioimmunoassay and reverse-phase high-performance liquid chromatography. Although plasma ir-ET was composed mainly of big ET and endothelin-1 (ET-1) in normal subjects, that in acute myocardial infarction, chronic renal failure (CRF), essential hypertension, and vasospastic angina pectoris was characterized by an increase of high molecular ir-ET in addition to increases in big ET and ET-1. Urinary ir-ET in both normal subjects and patients with CRF was composed mainly of a high molecular form in addition to big ET and ET-1. These results suggest that the biosynthetic and/or degradation process of ET under pathological conditions appears to be different from that under normal conditions.

Angina Pectoris↗
PubMed1990

[Clinical efficacy of Z-100 for the treatment of leukopenia caused by radiotherapy--a multi-center double-blind comparative study with inosine].

The clinical usefulness and the optimal dose of Z-100 for the treatment of leukopenia caused by radiotherapy for malignant tumors was evaluated in a double-blind study comparing 20 micrograms and 30 micrograms injections of Z-100 and inosine (Z-20, Z-30 and IN group, respectively). The effective rate according to the evaluation by the attending physicians was 67.4%, 79.1% and 48.9% in the Z-30, Z-20 and IN groups, respectively, with a significantly higher efficacy rate for the Z-20 group than for the IN group. The frequency of adverse reactions was 14.3%, 3.9% and 5.6% in the Z-30, Z-20 and IN groups, respectively, with the highest rate in the Z-30 group, but there was no significant difference among the three groups. The useful rate based on total evaluation considering the effective rate and the safety profile in each group was 60.8%, 77.3% and 46.8% in the Z-30, Z-20 and IN groups, respectively, with the highest rate in the Z-20 group showing significant difference from that in the IN group. The above data confirmed the clinical usefulness of Z-100 and suggested that the optimal dose was 20 micrograms twice weekly for Z-100.

Adjuvants, Immunologic↗
PubMed1990

[Clinical efficacy of Z-100 for the treatment of leukopenia caused by radiotherapy--a multi-center double-blind comparative study with L-cysteine].

The clinical usefulness of Z-100 (Z group) for the treatment of leukopenia caused by radiotherapy for malignant tumors was evaluated by comparing it with that of L-cysteine (L group) by the double-blind method. For 178 complete cases, there were no significant differences in the time-course of the WBC during radiotherapy between the two group. However, for cases with a large field of irradiation (15 X 15 cm = 225 cm2), the mean WBC count in the L group decreased more than that in the Z group. The Z group showed comparable or superior efficacy for the treatment of leukopenia in the L group although there were no significant differences. Adverse reactions were observed in 5.66% and 2.94% in the Z and L groups, respectively, without any significant difference between the groups. The utility rate, useful or better, was 73.9% and 69.2% in the Z and L groups, respectively, showing a slightly higher rate in the Z group than in the L group, although the difference between the two groups was not significant. These results confirmed that Z-100 has comparable or superior efficacy to L-cysteine for the treatment of leukopenia caused by large field radiotherapy for malignant tumors.

Adjuvants, Immunologic↗
PubMed1990

Nodular histiocytic lymphoma, emphasizing results of stage I disease treated by radiotherapy. A report of the Japan Lymphoma Radiation Therapy Study Group (JLRTG).

The records of 49 patients with nodular histiocytic lymphomas (NH) who were treated from 1972 to 1985 in hospitals belonging to the JLRTG were retrospectively reviewed. The actuarial survival rate and relapse-free survival rate of all patients after 5 years were 55.0 and 51.3%, respectively. Twenty-one patients with stage I disease had a significantly better survival rate than did 12 patients with stage II disease (P less than 0.01). Without combination chemotherapy, all 15 patients with stage I NH treated by radiation therapy were in complete remission, and 14 of them remained alive and well. Among these 15 patients, no difference in relapse was observed between patients who received involved field irradiation (1 of 6) and those who received extended field irradiation (2 of 9). Patients with stage II or more NH should be treated with intensive chemotherapy and radiotherapy, as are patients with diffuse histiocytic lymphoma (DH). However, involved field radiotherapy with careful follow-up observation may be the treatment of choice for patients with stage I NH, provided their tumors are not bulky.

Adult↗
PubMed1990

Compensatory adjustment in blood flow of the rabbit cerebral cortex during graded cerebral ischemia.

The role of the bilateral internal carotid and vertebral arteries in supplying cerebral cortex tissue blood flow (CTF) and the compensatory adjustment in CTF during graded cerebral ischemia were studied to determine the relationship to the increase in systemic arterial pressure (SAP) in anesthetized rabbits. CTF was recorded continuously by using Peltier stacks placed on both sides of the surface of the cerebral parietal cortex. Occlusion of the bilateral internal carotid arteries caused a decrease in CTF to 81.9% of the control value for the right hemisphere, and 83.5% of that for the left. Occlusion of the bilateral vertebral arteries produced no appreciable change in CTF. Compensatory adjustment in CTF was incomplete, i.e., CTF was reduced to a lower level, in the range of internal carotid flow (ICF) from 2 to 6 ml/min, and was severely reduced at 1 and 0 ml/min. The relationships between ICF and SAP, and ICF and CTF formed rectangular hyperbolic curves. No significant difference was observed between the decreases in CTF obtained before and after bilateral sectioning of the cervical sympathetic trunks. The relationship between SAP and CTF was described by a linear regression equation. These results indicate that the internal carotid arteries play a much more important role in supplying CTF than the vertebral arteries, that SAP rises in inverse proportion to the decrease in CTF, and that the cervical sympathetic trunks do not influence the compensatory adjustment in CTF caused by cerebral ischemia.

Animals↗
PubMed1990

Prognostic factors in head and neck non-Hodgkin's lymphoma with special reference to serum lactic dehydrogenase and serum copper.

An analysis of prognostic variables was performed in a retrospective study of 121 patients with Ann Arbor stage I-II head and neck non-Hodgkin's lymphoma admitted from 1973 to 1988. The overall actuarial 5-year survival rate was 58.8% and the minimum follow-up 15 months. Nine clinical and laboratory parameters were studied, including serum lactic dehydrogenase (LDH) and serum copper (SCL), and subjected to univariate and multivariate analyses. In univariate analysis, histology and LDH were found to be significant prognostic variables. Evaluation by Cox's multivariate proportional hazard model revealed histology, SCL and sex to be of prognostic significance.

Adolescent↗
PubMed1990

[Radiotherapy of local regional recurrences of a mastectomized breast carcinoma and its results].

Local-regional recurrences of a breast carcinoma after the mastectomy have been studied. A complete response rate of 89% was noted and this rate was found to decrease with an increase in the size of the mass. The most favorable local control rate was noted in carcinomas of the solitary nodular type where as the worst control late was seen in those with a lymph node metastasis. The 5-year survival rate in all cases was found to be 28.0%, and best in the solitary nodular type carcinomas and worst in carcinomas of the invasive type. Chestwall recurrences associated a local lymph node metastases were found to have a poorer prognosis compared to those without a lymph node metastasis.

Adult↗