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Biomedical subjects

K Murai

Publications and source records attributed to K Murai.

At least 73 records · Page 4Linked to original sources

A combination chemotherapy with low doses of cytarabine and etoposide for high risk myelodysplastic syndromes and their leukemic stage. A pilot study.

BACKGROUND: Even now, no definitely effective therapy is inducted to high risk myelodysplastic syndromes (MDS) and their leukemic stage (MDS-AML) except bone marrow transplantation. METHODS: Ten patients with high risk MDS and 6 with MDS-AML were treated with daily low doses of cytarabine (10 mg/m2/12h, infused over 2h) etoposide (50 mg/m2/day, infused over 2h). RESULTS: Fourteen of these patients were finally evaluated among whom 6 with high risk MDS and 3 with MDS-AML (64.3%) had complete remission, and 2 with high risk MDS (14.3%) achieved partial remission after this chemotherapy for 9 to 21 days. Three of 11 responders were resistant to the prior chemotherapies with single and low dose cytotoxic agents including cytarabine, etoposide, or aclarubicin. Although all of the patients who could be assessed developed severe marrow hypoplasia after chemotherapy, the nonhematologic side effects were mild enough to be tolerated. CONCLUSIONS: This combination chemotherapy must be effective and useful in high risk MDS and MDS-AML not only without prior chemotherapy but in cases which have been resistant to single and low dose oncostatic agent.

Adult↗

Light and electron microscopic studies of bone-titanium interface in the tibiae of young and mature rats.

Bone-titanium contact was examined in young and mature rats on various days after insertion of pure titanium into the tibia. Under light microscopy, on the 14th day, lamellar mature bone was initially formed, and was seen to make direct contact with the titanium in both groups. In young rats on the 28th day, bone-titanium contact was greater than that in mature animals. On 1-micron sections, an amorphous zone 0.5-1.0 micron thick was found around the titanium, and a slender cell layer lay parallel to the implant, forming the superficial layer of the amorphous zone. Ultrastructurally, these slender cells were identified as osteoblastlike cells and made direct contact with the implant via a 20-50-nm thin amorphous zone. Below this cell layer, a collagen-containing, poorly mineralized zone was present and bordered by lamellar bone with a lamina limitans-like structure. However, this cell layer was absent in places, and therefore the thick amorphous zone without slender cell layer consisted ultrastructurally of a 20-50-nm thin amorphous zone and a poorly mineralized zone bordered by the lamellar bone. Sometimes this poorly mineralized zone was absent, and in such cases, the lamellar bone contacted the titanium by the thin amorphous zone formed on the lamina limitans-like structure. Thus, although bone was seen to make contact with the titanium implant, ultrastructurally a 20-50-nm thin amorphous zone, a slender cell layer, and/or a poorly mineralized zone were interposed between the bone and titanium.

Animals↗

Enhanced engraftment of HTLV-I-infected human T cells in severe combined immunodeficiency mice by anti-asialo GM-1 antibody treatment.

The effects of anti-asialo GM-1 antibody (AAGM) treatment on the engraftment of human T-cell leukemia virus type I (HTLV-I)-infected human T cells in severe combined immunodeficiency (SCID) mice were studied. The frequency of tumor formation in an HTLV-I-transformed human T-cell line, MT-2 cells, at the site of inoculation was significantly higher in AAGM-treated than untreated mice (P<0.05): 16/18 (89%) and 16/26 (62%), respectively. The promotive effect of AAGM treatment on tumor development was marked in the early stage (less than 3 weeks), suggesting that the immediate reaction of natural killers to the inoculated cells may be important for the prevention of tumor development. The surface phenotypes and clonality of the tumor cells were the same as the MT-2 cells inoculated. Inoculation of peripheral blood mononuclear cells (PBMC) from one of the 4 adult T-cell leukemia/lymphoma (ATL) patients resulted in the development of tumors in AAGM-treated SCID mice. However, the surface phenotypes of the cells from these tumors were a mixture of B cells and T cells, suggesting that these tumors consisted of Epstein-Barr virus-transformed B cells and HTLV-I-transformed T cells. In addition, HTLV-I was detected by polymerase chain reaction in various organs of the mice inoculated with PBMC from the ATL patient and the asymptomatic carrier examined. These results suggest that elimination of natural killer function by AAGM treatment is important, although such treatment is not always necessary for the engraftment of HTLV-I-infected cells in SCID mice.

Animals↗

[Hearing acuity in the elderly in Japan].

In Japan, the elderly population has progressively increased. It is therefore expected that various social services for the elderly will be demanded. As most of the elderly have hearing impairment due to presbycusis, it is difficult to communicate smoothly with them. To provide the various social services, it is necessary to investigate hearing acuity in the elderly. Accordingly, the Hearing Research Group, which belongs to the Research Project on Aging and Health in the Ministry of Health and Welfare of Japan, investigated the hearing acuity of people 65 years old, or more. One thousand one hundred ninety two subjects were divided into five groups, Group A consisted of 170 males and 216 females between 65 and 69 years old, Group B, 186 males and 158 females between 70 and 74; Group C, 147 males and 140 females between 75 and 79; Group D, 63 males and 61 females between 80 and 84; and Group E, 29 males and 22 females 85 years old or more. We examined the 175 subjects 80 years old or more. Therefore, it is considered that this study could indicate the present condition of hearing acuity of the elderly of Japan. The average hearing levels measured at seven frequencies (125, 250 and 500Hz, and 1, 2, 4, and 8KHz) were 35.0dB in group A, 42.1 in group B, 46.1 in group C, 52.1 in group D, and 55.6 in group E. There were no differences in the average hearing level between males and females in any group. The audiogram pattern indicated a gradually descending curve in most subjects in all groups. The average speech discrimination rate was 75.4% in group A, 70% in group B, 63.8% in group C, 59.7% in group D, and 52.1% in group E. The percentage of subjects showing a short increment sensitivity index of more than 70% was 45.2% in group A, 49.3% in group B, 47.9% in group C, 51.6% in group D, and 59.7% in group D. In conclusion, hearing loss due to aging tended to be more progressive at higher frequencies while hearing acuity of frequencies covering normal speech was preserved. However, the speech discrimination rate decreased relative to changes in the pure tone hearing level. It was considered that the pathology of hearing loss due to aging begins with retrocochlear changes and cochlear factors are added to retrocochlear changes with aging.

Aged↗

Genotypic identification of Rickettsia tsutsugamushi by restriction fragment length polymorphism analysis of DNA amplified by the polymerase chain reaction.

We combined the nested polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) for genotypic identification of Rickettsia tsutsugamushi. Four primers were selected from the DNA sequence of the gene encoding a 56-kD serotype-specific antigen of the Karp strain. Nested PCR produced rickettsia-specific products of approximately 0.6 kb in the amplification of DNA prepared from three reference strains (Gilliam, Karp, and Kato) and two prototype strains (Irie and Hirano) prevalent in the Miyazaki Prefecture of Japan. When the nested PCR products obtained from these five strains were digested with Hha I, profiles specific to each strain were generated. Fourteen of 17 DNA samples of peripheral blood mononuclear cells from patients with scrub typhus tested positive in the nested-PCR, providing a rickettsia-specific band. The serotype of infected rickettsia of 10 patients were diagnosed as Irie and those of four patients were diagnosed as Hirano by indirect immunofluorescence methods. The fragment profiles of the PCR products of these 14 patients after digestion with Hha I corresponded closely with those serotypes. However, the PCR products from two of four samples, which were similar to Hirano strain by a serologic method and by the pattern of digestion with Hha I, produced different RFLP profiles upon further digestion with Hinf I and Alu I. These results may suggest that genetic variation exists within serotypes. Genotypic identification of R. tsutsugamushi by means of PCR-RFLP using three restriction enzymes is apparently useful.

Adult↗

[Interleukin-3 therapy in patients with aplastic anemia refractory to prior therapies].

A therapeutic trial of interleukin-3 (IL-3) was carried out in four patients with aplastic anemia refractory to the prior therapies. Daily subcutaneous doses of 2.5, 5.0 or 7.5 micrograms/kg was given for 7 or 14 days. In a patient who had co- and immediate boost-administration of granulocyte colony-stimulating factor (G-CSF) and/or erythropoietin (Epo) and another who had sequential administration of G-CSF and Epo two weeks after IL-3, definite hematological response was obtained during the course after IL-3. In one patient, moderate to severe side effects consisting of facial edema, conjunctival bleeding, chills and fever, were observed after two days' administration of IL-3. Co- or sequential administration of other hemopoietic factor(s) may be essential in IL-3 therapy for aplastic anemia.

Adult↗

Effects of apple pectin on fecal bacterial enzymes in azoxymethane-induced rat colon carcinogenesis.

Because of the potential significance of colonic bacteria in colon carcinogenesis, we investigated the effect of pectin of different types on fecal bacterial enzymes (beta-glucuronidase, beta-glucosidase and tryptophanase) at various periods of time after feeding rats with pectin-containing diets during azoxymethane-induced colon carcinogenesis. The diet supplemented with 20% apple pectin or 20% citrus pectin decreased the multiplicity of colon tumors, and the number of tumors was significantly decreased in the group fed apple pectin. The incidence of colon tumors in the apple pectin group was lower than that in the control group. The mean tumor size was similar among the three groups. Apple pectin feeding decreased fecal beta-glucosidase and tryptophanase levels. Furthermore, a significant decrease in the activity of beta-glucuronidase was observed in the apple pectin group during the initiation phase. These findings suggest that the protective effect of pectin on colon carcinogenesis may be dependent on the type of pectin and be related to the decrease of beta-glucuronidase activity in the initiation stage of carcinogenesis.

Adenocarcinoma↗

Eradication of Rickettsia tsutsugamushi from patients' blood by chemotherapy, as assessed by the polymerase chain reaction.

The presence of Rickettsia tsutsugamushi DNA in peripheral blood mononuclear cells of eight patients with tsutsugamushi disease was determined by the polymerase chain reaction during antibiotic treatment with minocycline or doxycycline. Rickettsia tsutsugamushi DNA was detectable in all samples from these patients collected the day before treatment began. After the initiation of chemotherapy, all samples tested positive on the third or fourth day, and one sample tested positive on the eighth day, showing a slow action of the drugs against the rickettsia within cells. Immune responses against R. tsutsugamushi also seemed to be important for eradication of the pathogens, as suggested by patients' high antibody titers.

Aged↗

[Effects of combined aprotinin and prostagrandin E1 therapy on aortic arch replacement].

This study was undertaken to compare the effects of combined aprotinin and prostaglandin E1 therapy on aortic arch replacement. Twenty patients were divided into 2 groups with (group A; n = 10) or without (group B; n = 10) the treatment (200 KIU of aprotinin and 0.01-0.02 microgram/kg/min of prostaglandin E1 during cardiopulmonary bypass (CPB) and the first postoperative day. Preoperative evaluation of respiratory function and all parameters related to CPB procedure were revealed to be equal between the groups. Postoperative A-a DO2 and respiratory index (RI) as functional parameters of oxygenation capacity, dosage of dopamine were monitored at 0, 3, 6, 12, 18 and 24 hr after termination of CPB and at extubation period. Serum creatinine, platelet numbers and blood coagulation function (PT, APTT) were also assayed postoperatively. The recovery of respiratory and cardiac function were superior in group A with treatment, but renal and blood coagulation function showed no difference in the groups. We suggest the combined therapy with aprotinin and prostaglandin E1 for aortic arch replacement may emerge as a valuable treatment to save postoperative respiratory and cardiac function.

Alprostadil↗

[A case of pulmonary arteriovenous fistula failed in transcatheter embolization and followed by emergency operation].

We reported a 55-year-old male case with pulmonary arteriovenous fistula. The lesion existed in right S9b and was about 6 cm in diameter. The afferent artery and the efferent vein, both were more than 10 mm in diameter, were shown on the chest CT and DSA film. At first transcatheter embolization with steel coils and Histoacryl was tried. Though we succeeded in embolization of the afferent artery, embolization of the fistula was failed because of reflux from the drainage vein. And a coil, a fragment of Histoacryl dropped and floated in the fistula. With concerning about the risk of embolization of the other organ with these materials, we performed the enucleation of the fistula at the next day. Although transcatheter embolization is useful in treating pulmonary arteriovenous fistula, in the case of wide communication with large drainage vein such as our case, it seems to be risky.

Arteriovenous Fistula↗

[Initiation of hematopoietic recovery by recombinant human granulocyte-macrophage colony-stimulating factor in a case of severe aplastic anemia induced by gold salt].

A 65-year-old female with severe aplastic anemia induced by gold salt, whose hematopoietic recovery was initiated by rhGM-CSF therapy, was reported. The patient has been given a total of 500 mg of gold-sodium thiomalate for treatment of her rheumatoid arthritis. Two months after the final administration of it, she was admitted to our hospital with complaints of palpitation and shortness of breath. The hemogulobin was 5.9 g/dl, the platelet count was 0.5 x 10(4)/microliter, and the leukocyte count was 800/microliters with 19% neutrophils. Her bone marrow showed aplasia, and both of Ham and sugar-water tests were positive. Three times of bolus-methylprednisolone treatment, with or without methenolone acetate, resulted in no definite improvement of peripheral pancytopenia and marrow aplasia. Subsequent subcutaneous rhGM-CSF, 300 micrograms daily for 28 days with oral prednisolone 5 mg and methenolone acetate 40 mg daily, initiated hematopoietic recovery of all three cell lineages in both peripheral blood and bone marrow. The same doses of prednisolone and methenolone acetate were continued after rhGM-CSF administration, and three months later peripheral cytopenia and positive Ham and sugar-water tests disappeared completely.

Aged↗

[Morphological observation of a process of bone marrow hypoplastic formation in a case of aplastic anemia].

Bone marrow morphological change was consecutively analyzed form the disease onset to the formation of bone marrow aplasia in a patient with post-hepatitic aplastic anemia. In this case, the mean bone marrow cellularity and absolute numbers of erythroids and megakaryocytes were continuously higher than those in normal subjects for 3 weeks after the appearance of peripheral pancytopenia. During this stage, administration of recombinant human granulocyte colony-stimulating factor (G-CSF) improved marrow myeloid hypoplasia and peripheral neutropenia. During the period in which the marrow cellularity transformed from hyperplasia to hypoplasia, the bone marrow showed a mixture of hyper-, normo- and hypocellular portions, and the decrease in the megakaryocytes was the faster than myeloid and erythroid cells. These findings indicate that (1) ineffective hematopoiesis might be present in the early stage of the disease, (2) G-CSF responsive granulocytic precursors remained during the early stage of the disease, and (3) the marrow aplasia progressed in the manner of aplastic nest formation during the period in which the marrow cellularity declined to hypoplasia. We experienced another case of aplastic anemia showing the same progress of bone marrow findings and speculated that this might be one of the ways of the progression of bone marrow hypoplastic formation in aplastic anemia.

Adolescent↗

[Hematological stability under ubenimex monotherapy in a patient with acute myelogenous leukemia developing marrow karyotypic changes during the course].

We encountered a 71-year-old female with acute myelogenous leukemia (AML, M1), who maintained a steady hematological state for 22 months under ubenimex monotherapy. At the first medical examination in our hospital, the marrow cellularity was approximately 40% containing leukemic myeloblasts of 41.4% in the total nucleated cells, and the marrow cytogenetic study revealed 47, XX, + 8 in 13 of 20 cells analyzed. Nineteen months later, the bone marrow showed definite hypoplasia with leukemic blasts of 39.8% and chromosome finding of 46, XX, ins (10;?) (q11;?) in all cells analyzed. During the course, the patient has been doing well without transfusion of red blood cells or platelets.

Aged↗