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Biomedical subjects

M Harada

Publications and source records attributed to M Harada.

At least 613 records · Page 34Linked to original sources

[A trial for quantification of proton MR spectroscopy: relaxation times of each metabolite and concentration using water signal as an internal standard].

We conducted quantification of proton MR spectroscopy (1H-MRS) using water signal as an internal standard. The 1H-MR spectrum was measured with and without water suppression pulses. For calculation of relaxation times, measurement conditions of the PRESS sequence were as follows: TR = 1500, 3000, 5000 ms, TE = 135,270 ms. The T1 relaxation and T2 relaxation of each metabolite were calculated by fitting to the curve of the equation of the spin echo sequence. The signal intensities of each metabolite were corrected using relaxation times and such corrected intensities were used for the quantitative calculation. The concentration of each metabolite was obtained from ratios of the corrected intensities of water and metabolites. The value of each concentration was coincident with that reported in the previous literature. We considered that this quantification using water signal as an internal standard would be very useful when the proton-weighted image does not show remarkable change.

Adult↗

Early-appearing tumour-infiltrating natural killer cells play a crucial role in the generation of anti-tumour T lymphocytes.

Natural killer (NK) cells that infiltrated into the primary tumour site at an early stage of tumour development, were examined for their participation in the generation of anti-tumour cytotoxic T lymphocytes (CTL). NK cells, which were detected by anti-NK1.1 monoclonal antibody (mAb), increased in the peritoneal exudate cells (PEC) on days 3 and 7 after an intraperitoneal (i.p.) inoculation of syngeneic B16 melanoma cells. These tumour-infiltrating NK cells showed a high level of cytotoxic activity against NK-sensitive YAC-1 cells and an increased expression of interferon-gamma (IFN-gamma) mRNA and interleukin-2 (IL-2) mRNA. The in vivo depletion of NK cells with anti-NK1.1 mAb, prior to i.p. inoculation of B16 melanoma cells, resulted in an increased number of tumour cells in the PEC compared to NK cell non-depleted mice. Interestingly, the differences in tumour cell number between both groups were more prominent on days 7 and 14 than on day 3, which strongly suggested that early-infiltrating NK cells have a large influence on the subsequent anti-tumour response. The in vivo depletion of NK cells prior to immunization with melanoma cells abrogated the capacity of the spleen cells to generate CD8+ tumour-specific CTL after in vitro restimulation. This inability of generating anti-tumour CTL was partially restored by additional i.p. injections of recombinant IL-2 and/or IFN-gamma simultaneously with the immunization of melanoma cells. The in vitro depletion of NK cells prior to the in vitro restimulation with melanoma cells partially impaired the anti-tumour CTL generation from the spleen cells of the immunized mice. Lastly, the in vivo depletion of NK cells prior to immunization with melanoma cells abolished the protective immunity against melanoma cells at the rechallenge. Overall, these results indicate that early-appearing tumour-infiltrating NK cells not only participate in the anti-tumour early defence by themselves, but also play a crucial role in the generation of anti-tumour CTL.

Animals↗

[A preliminary analysis of unrelated marrow transplantations facilitated by the Japan Marrow Donor Program (JMDP)].

Between January 1993 and June 1994, the JMDP facilitated marrow donations from unrelated donors for 171 patients with malignant and non-malignant disorders. The median age of the patients was 21 years. All patients received marrow from phenotypically HLA -A, -B, -DR identical donors. About half of the patients wrer treated with total body irradiation (TBI)-containing regimens and about 80% of the patients received short-courses methotrexate and cyclosporine for graft-versus-host disease (GVHD) prophylaxis. Eight out of 171 patients, (4.7%) had graft failure and 63 out of 144 patients (44%), who survived for more than 30 days posttransplant, developed grade II to IV acute GVHD. The incidence of chronic GVHD was 47% (extensive form; 27%); most of them were progressive/quiscent type. The incidence of moderate to severe acute GVHD was higher than that observed in sibling transplants. On the other hand, the incidence of chronic GVHD was similar to that observed in sibling transplants. Overall survival at 1.5 years posttransplant was about 50% with no significant differences between diseases. The age correlated significantly with the survival in standard risk leukemia but not in high-risk leukemia. Despite the risk of graft failure and acute GVHD, this preliminary analysis demonstrates that transplantation of marrow from unrelated donors can be an effective treatment for certain hematologic disorders.

Acute Disease↗

[Autologous blood stem cell transplantation-current status and issues. Fukuoka Bone Marrow Transplantation Group].

Autologous blood stem cell transplantation (ABSCT) has been increasingly used in the treatment of malignant diseases. With the use of hematopoietic cytokines, collection of peripheral blood stem cell (PBSC) has become easier. Contamination of PBSC with tumor cells is supposed to be reflecting the amount of residual tumor cells in the host. G-CSF combined conditioning regimen seems to be effective for ANLL in complete remission (CR) probably by in vivo purging of residual leukemic cells. From our preliminary results, ABSCT can be used as the treatment of choice for standard risk ANLL, and aggressive non-Hodgkin's lymphoma. To clarify the curative potential of ABSCT, prospective clinical trial consisting of remission induction, consolidation of CR, PBSC harvests, and marrow-ablative therapy for ABSCT will be required.

Antineoplastic Combined Chemotherapy Protocols↗

Effects of extracellular matrices on tube formation of cultured rat hepatic sinusoidal endothelial cells.

To determine the effects of extracellular matrices on the function and morphology of hepatic sinusoidal endothelial cells, isolated rat hepatic sinusoidal endothelial cells were cultured in three-dimensional fashion on collagen gel containing various extracellular matrix components. Cells cultured on type I collagen gel with or without type IV collagen formed a cobblestone appearance on the surface of the gel. Cells cultured on laminin-containing type I collagen gel invaded the gel and exhibited three-dimensional tube formation with a decreased number of characteristic endothelial pores. Morphometrically, there was a significant relationship between the length of the tube formed and the concentration of laminin in the type I collagen gel. Cells cultured on Matrigel, which contains high concentrations of laminin, type IV collagen, fibroblast growth factor, tissue plasminogen activator, and other growth factors, formed a great number of tubes into a network on the surface of the gel, as is observed in the situ hepatic sinusoidal endothelial cells. Ultrastructurally, tube-forming endothelial cells cultured on Matrigel had many endothelial pores on the cell surface, with tubes (approximately 10 microns in diameter) formed by two or three hepatic sinusoidal endothelial cells. These results indicated that extracellular matrix components, especially laminin, induced the formation of tubes in cultured rat hepatic sinusoidal endothelial cells. Tube-forming sinusoidal endothelial cells cultured on Matrigel could provide more advantages than the two-dimensional culture model for investigating the function and morphology of these cells in vitro.

Animals↗

[Proton MR spectroscopy of the brain in patients with congenital myotonic dystrophy].

Volume selective proton MR spectroscopy (1H-MRS) of the brain was performed on a 1.5T magnet in five patients with congenital muscular dystrophy (CMyD), 46 healthy children, and one healthy adult. Peaks of N-acetylaspartate (NAA), choline (Cho) and creatine (Cr) were observed in both patients and control groups on 1H-MRS, but lactate was not observed. 1H-MRS revealed an increase in the ratio of NAA/Cho and NAA/Cr, and a decrease in Cho/Cr ratio with age in control subjects. In patients with CMyD, the values of NAA/Cho ratio did not increase with age. The values of NAA/Cr ratio decreased with age. The values of Cho/Cr ratio decreased with age in both patient and control groups. At age more than 4 years, the values of NAA/Cho and NAA/Cr ratios were lower in patients with CMyD than in controls. The values of Cho/Cr ratio did not differ between CMyD and controls. These results suggest that in patients with CMyD, there is an NAA decrease and a developmental disorder of neurons in the brain.

Adolescent↗

[Treatment of middle and lower ureteral stones with ESWL: evaluation of the results of 190 solitary stones in comparison with those of upper ureteral stones].

We analyzed the results of treatment with extracorporeal shock wave lithotripsy (ESWL) (Dornier HM-3) for middle and lower ureteral solitary stones from April 1986 to March 1993 in our hospital. A total of 238 sessions of ESWL were done for 71 cases of middle ureteral stones and 119 cases of lower ureteral stones. The findings were compared with those obtained on the upper ureteral solitary stones. The final stone-free rate of the upper ureteral stones by ESWL alone were 91.9%, whereas those of middle and lower ureteral stones were 86.2% and 85.2%. We conclude that ESWL is equally useful for middle and lower ureteral stones to upper ureteral stones.

Adult↗

[Use of intravenous hyperalimentation catheter to drainage prolonged postoperative pleural effusion after harvesting the internal thoracic artery].

Increased chest drainage, a higher incidence of pleural effusions in the postoperative period, and more chest tube drainage was found after harvesting the internal thoracic artery (ITA). Patients with these complications required thoracocentesis, or prolonged chest tube drainage. But these methods may be painful and make a limitation to activity of daily life (ADL) in these patients. We therefore sought an effective procedure for these patients, and applied pleural placement of intravenous hyperalimentation catheter. This technique could drain the effusion completely, conveniently and painlessly without a limitation to ADL. Pneumothorax, infections and other complications occurred in no patients. We concluded that this method might be useful in these patients with prolonged post operative pleural effusion after harvesting the ITA who have failed other modes of therapy.

Aged↗

[Successful treatment of refractory anemia with excess of blasts in transformation with cytarabine ocfosfate].

A 58-year-old female was diagnosed as myelodysplastic syndrome (MDS) [refractory anemia with excess of blasts (RAEB)]. Although melphalan was administered, no response was obtained in the peripheral blood. Sixteen months after diagnosis, she developed RAEB in transformation (RAEB-t), and then overt leukemia. White blood cell (WBC) count elevated to 28,600/microliters with 34% of blasts. She was administered cytarabine ocfosfate (200 mg-->300 mg/day) orally, resulting in decrease of WBC count and blasts in peripheral blood. The drug has been given for 11 months, and her hematological data have now remained stable in RAEB. Cytarabine ocfosfate might be a useful drug for the treatment of high risk MDS such as RAEB and RAEB-t.

Acute Disease↗

[Gingival metastasis of large-cell lung cancer that produced G-CSF].

A 68-year-old man was referred to our hospital for further examination of a gingival mass. Chest radiographs and magnetic resonance imaging disclosed a bulky mass originating in the upper portion of the left lung, in contact with a chronic empyema lesion that first occurred after resection for pulmonary tuberculosis. Examination of a specimen obtained by percutaneous needle biopsy of the mass led to the diagnosis of large-cell carcinoma. Laboratory findings on admission showed marked leukocytosis (48,100/microliter) without evidence of severe a bacterial infection. The level of G-CSF in serum was abnormally high (246 pg/ml, normal value: < 30 pg/ml). Chemotherapy with vindesine, ifosfamide, and cisplatin resulted in shrinkage of the gingival mass, and a decrease in the G-CSF level to 66 pg/ml. Immunohistochemical staining with an anti-G-CSF monoclonal antibody to the primary lung tumor and the gingival mass obtained at autopsy was positive for cytoplasmic G-CSF.

Aged↗

MR of childhood-onset dentatorubral-pallidoluysian atrophy.

MR findings in a 14-year-old boy with progressive myoclonic epilepsy, who was diagnosed as having dentatorubral-pallidoluysian atrophy by DNA analysis, were compared with those of his father, who had adult-onset dentatorubral-pallidoluysian atrophy. Besides showing severe brain atrophy, especially of the brain stem tegmentum and cerebellum, MR showed diffuse periventricular hyperintensity on T2-weighted images. As compared with the proband, the father had a mild case.

Adolescent↗

[Percutaneous transluminal angioplasty of the ilio-femoro-popliteal arteries: initial and long-term results].

The initial and long-term results of percutaneous transluminal angioplasty (PTA) were assessed in 254 atherosclerotic lesions of the ilio-femoro-popliteal arteries in 130 patients. There were 122 men and 8 women, aged 36-85 years (average, 68 years). Follow-up periods ranged from 1 to 131 months, with a mean of 42 months. PTA was performed in 6 patients in Fontaine's stage I, 112 patients in stage II, and 12 patients in stage III-IV. We reported initial success rates of 92%, 58%, 83% and 74% for iliac stenosis, occlusion, femoro-popliteal stenosis and occlusion, respectively. Overall, the initial success rate was 82% (203/247). The 5-year patency rates according to Kaplan-Meier analysis were 70%, 69% and 63% for iliac stenosis, occlusion and femoro-popliteal stenosis, respectively. In femoro-popliteal occlusion, the 1-year patency rate was 42%, which was significantly worse than that for stenosis (P < 0.01). The longest patency periods obtained were 131 months in the iliac artery, and 106 months in the femoro-popliteal artery. The recurrence rate within 6 months was significantly higher in patients with diabetes. The recurrence rate between 6 and 12 months was significantly higher in patients with poor run-off, and those of advanced age.

Adult↗