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Biomedical subjects

K Akashi

Publications and source records attributed to K Akashi.

At least 109 records · Page 6Linked to original sources
PubMed1993

Evaluation of leukaemic contamination in peripheral blood stem cell harvests by reverse transcriptase polymerase chain reaction.

A major issue in autologous blood stem cell transplantation (ABSCT) for leukaemia is whether peripheral blood stem cell (PBSC) harvests are less contaminated with leukaemic cells than bone marrow mononuclear cells (BMMNC). We compared leukaemic contamination in PBSC harvests and BMMNC, obtained simultaneously, by using reverse transcriptase polymerase chain reaction (RT-PCR) of leukaemia-specific chimaeric messenger RNA (mRNA), in three patients with Philadelphia chromosome (Ph)-positive acute lymphoblastic leukaemia (ALL), one with Ph-positive acute myelogenous leukaemia (AML), and two with acute promyelocytic leukaemia (APL). Our two-step PCR method employed 'nested primers' in the second step and can detect one leukaemic blast diluted into 10(6) HL-60 cells. In three of four patients with Ph-positive ALL and AML we detected leukaemic contamination in both PBSC harvests and BMMNC. In the remaining patient with ALL, both PBSC harvests and BMMNC were PCR-negative. Both PBSC harvests and BMMNC from one patient with APL were PCR-positive. In contrast, PBSC harvests from another patient with APL, whose BMMNC could not be obtained because of bone marrow necrosis, were PCR-positive after the first course of consolidation chemotherapy, but became PCR-negative after the second course. The present study does not support the hypothesis that PBSC harvests are less contaminated by leukaemic cells than BMMNC, but suggests that PBSC harvests are contaminated when BMMNC are contaminated.

Adult↗
PubMed1993

Cytokine production by peripheral blood monocytes and T cells during haemopoietic recovery after intensive chemotherapy.

We studied the production of cytokines by peripheral blood monocytes and T cells during the period of haematological recovery following intensive chemotherapy. Twelve adults with haematological malignancies received consolidation chemotherapy of complete remission. Monocytes and T cells were collected during the phase of recovery from intensive chemotherapy, and were incubated for 24 h in a culture medium with 10% FCS. Concentrations of cytokines in the culture supernatant were measured with an enzyme-linked immunosorbent assay. During the recovery phase, concentrations of IL-6, G-CSF and IL-1 beta in the culture supernatant of the collected monocytes significantly exceeded those of the monocytes obtained from normal healthy subjects. Similarly, the concentrations of GM-CSF and IFN-gamma in the supernatant of recovery phase T cells significantly exceeded those of normal T cells. Plasma levels of these cytokines were also elevated. These data suggest that the monocytes and T cells may be activated in vivo to produce haemopoietic cytokines during haematological recovery, and that, during haematological recovery, the monocytes and T cells may be actively involved in the induction of haematopoiesis following the myelosuppression induced by chemotherapy.

Adolescent↗
PubMed1993

The role of interleukin-4 in the negative regulation of leukemia cell growth.

Interleukin-4 (IL-4), originally identified as a B-cell growth factor, has been shown to inhibit certain stages of hematopoietic stem cells. Recently, IL-4 has been recognized as a negative regulatory factor in the growth of hematologic malignancy. In myeloid leukemias, IL-4 can suppress the growth of growth factor-dependent leukemic blast cells derived from acute myelogenous leukemia (AML). IL-4 also suppresses the growth of chronic myelomonocytic leukemia cells through inhibiting the "autocrine" production of IL-6 or granulocyte/macrophage colony-stimulating factor. In lymphoid malignancies, IL-4 can inhibit the proliferation of neoplastic cells from Ph1-positive acute lymphoblastic leukemia, non-Hodgkin's B-cell lymphoma, and multiple myeloma. Thus, IL-4 is expected to be useful as a therapeutic agent for these hematologic malignancies.

Antigens, CD↗
PubMed1993

T lymphoid/myeloid bilineal crisis in chronic myelogenous leukemia.

We describe 2 cases of "bilineal" crisis in chronic myelogenous leukemia (CML) with T cell and myeloid phenotypes. In both cases, morphocytochemically distinct myeloid and T lymphoid blast populations proliferated simultaneously in the phase of blastic crisis--myeloperoxidase (MPO)-positive, CD7+/CD33+ myeloblasts in the peripheral blood, and MPO-negative, periodic acid Schiff (PAS)-positive lymphoblasts in the lymph nodes. In each case, common karyotypes containing Ph1 translocation were demonstrated in both the peripheral blood and the lymph node samples. In Case 1, the lymph nodes were occupied by > 90% lymphoblasts, which were positive for CD2, cytoplasmic CD3 (cCD3), CD5 and CD7 and terminal deoxynucleotidyl transferase (TdT), but negative for myeloid antigens. Myeloblasts and T lymphoblasts showed an identical rearrangement of the bcr gene by Southern blotting analysis, although the clonal rearrangement of the T cell receptor (TcR)-delta gene was seen only in T lymphoblasts. In Case 2, simultaneous proliferation of myeloblasts and lymphoblasts was documented morphocytochemically in the lymph node, and a flow cytometric analysis revealed the coexistence of CD7+/CD33+ and CD7+/CD33- blast populations. Each blast population was enriched by antibody-conjugated immunomagnetic beads; the former was positive for MPO by 64% but negative for cCD3 and TdT, whereas the latter was positive for cCD3 and TdT but negative for MPO (< 1%). CD7+/CD33+ myeloblasts and CD7+/CD33- lymphoblasts showed an identical rearrangement of the bcr gene. Neither TcR-beta, TcR-gamma nor the TcR-delta gene was clonally rearranged in either population. These observations clearly indicate that T lymphoid and myeloid blasts share common Ph1-positive progenitors, and that Ph1-positive T lymphoid/myeloid progenitors are probably involved in the development of blastic transformation in some percentage of CML patients.

Adult↗
PubMed1993

[Cytomegalovirus antigenemia in the differential diagnosis of pulmonary infiltrates after allogeneic bone marrow transplantation].

For the differential diagnosis of pulmonary infiltrates after bone marrow transplantation, cytomegalovirus (CMV) antigenemia was evaluated in 9 episodes of pneumonia which developed in 7 allogeneic marrow transplant patients between 9 and 495 days after transplant. The diagnosis of lung infiltration was made based on clinical findings including histological, cytological or microbiological examinations using bronchoalveolar lavage fluid specimens, sputum or lung tissue. The CMV antigen-positive leukocytes were detected with a direct immunoperoxidase technique using a peroxidase-labeled monoclonal antibody (HRP-C7) against CMV immediate early antigen. The episodes included 2 CMV pneumonias, 1 pneumocystis carinii pneumonia, 1 adenovirus pneumonia, 1 bacterial pneumonia, 1 bacterial and fungal pneumonia, 2 idiopathic pneumonias and 1 capillary leak syndrome associated with hyper acute GVHD. The CMV antigenemia became positive only in two patients with CMV pneumonia and the number of CMV antigen-positive leukocytes exceeded 10 per 50000 WBCs. The CMV antigenemia test required only 24 hours to obtain results. These observations suggest that the detection of CMV antigenemia is of great value in the differential diagnosis of pulmonary infiltrates in marrow transplant patients.

Adult↗
PubMed1993

Cyclosporine combined with methylprednisolone or methotrexate in prophylaxis of moderate to severe acute graft-versus-host disease.

To evaluate the efficacy of cyclosporine (CYA) regimens in preventing moderate to severe acute graft-versus-host disease (GVHD), 25 patients received immunosuppressive therapy consisting of either CYA and methylprednisolone or CYA and methotrexate (MTX) and the incidence and severity of acute GVHD was compared. These patients had leukemia or myelodysplastic syndrome (MDS) and received bone marrow transplants (BMT) from genotypically HLA-identical siblings. The incidence of grade I-IV acute GVHD in patients on the CYA/methylprednisolone regimen was 64% (7 of 11) compared with 50% (7 of 14) in those on the CYA/MTX regimen. Five of 11 patients with the CYA/methylprednisolone regimen developed moderate to severe acute GVHD (grade II-IV), fatal in 3 cases. No patient on the CYA/MTX regimen developed moderate to severe acute GVHD. Engraftment was faster in the CYA/methylprednisolone group than in the CYA/MTX group. The incidence of toxicity observed soon after BMT was comparable between groups. The CYA/MTX regimen may be superior to the CYA/methylprednisolone regimen for preventing moderate to severe acute GVHD.

Acute Disease↗
PubMed1993

[Influences of anesthetic method on post-cholecystectomy pain--a comparison between epidural and general anesthesia].

This study was designed to compare the influence of epidural anesthesia with that of general anesthesia on postoperative pain state and management. We studied 16 patients who underwent elective laparotomy-cholecystectomy with epidural anesthesia without general anesthesia or with general anesthesia (nitrous oxide-isoflurane). Following bolus epidural injection with 3 micrograms.kg-1 of buprenorphine in 0.25% bupivacaine 4-7 ml at the end of surgery, all patients received continuous epidural buprenorphine administration at the rate of 12 micrograms.h-1 for 48 hours. Pain relief was assessed for 72 hours after surgery using visual analogue scale. Postoperative rest pain of the epidural group remained at a lower state of pain than that of the general anesthesia group not only for 48 hours (P < 0.005) but also until 72 hours (P < 0.005) after surgery. We concluded that the epidural anesthesia produces a greater postoperative pain relief than general anesthesia.

Anesthesia, Epidural↗
PubMed1993

[Basis of cytokines--history and present status].

Cytokines are high molecular-weight substances which actively promote homeostasis and defend from exogenous agents. In 1965, Kasakura, et al, and Gordon, et al independently published articles describing an unknown substance (blastogenic factor) which was produced in the cultured media of lymphocytes and stimulated lymphocytic proliferation. In those days, since almost all immunologists believed that only antigens stimulated lymphocytic proliferation, the idea that this soluble factor actually had a positive role in lymphocytic proliferation was viewed suspiciously. Later, it was found that immune responses are constructed of mutual intercellular stimulations between T and B lymphocytes and macrophages. In the 1970s, several kinds of cytokines were found. Cytokines include lymphokines and monokines. These were named for substances produced from lymphocytes and monocytes, respectively. In 1972, at the second lymphokine workshop in Switzerland, a new term, "interleukin", was accepted as the name of an active substance which reacts mutually among leukocytes. Specific interleukins (IL) are numbered, e.g. IL-1, 2, 3 and so on. Later, a new term, BRM (biological responsive modifiers), was added to denote substances including not only cytokines but also other high weight molecules acting on various kinds of cells and tissues. Among the various kinds of cytokines, CSF (colony stimulating factor), Epo (erythropoietin), IL, TNF, and interferon are well known. In particular, CSF and Epo have been widely used for granulopenia and renal anemia with remarkable effects.

Animals↗
PubMed1993

[Idiopathic interstitial pneumonitis possibly associated with chronic graft-versus-host disease].

We described two cases of idiopathic interstitial pneumonitis (IP) after allogeneic bone marrow transplantation (BMT), who were successfully treated with prednisolone (PSL). A 40-year-old male with AML (M3) in the first remission (case 1) and a 36-year-old male with CML in chronic phase (case 2) were treated with BMT from HLA genotypically identical female siblings. Both patients were conditioned with busulfan (16mg/kg) and cyclophosphamide (120mg/kg), and given a combination of cyclosporin A and methotrexate to prevent acute GVHD (aGVHD). Engraftment of donor marrow was documented in both cases. Grade I of aGVHE developed in case 1 and no aGVHD in case 2. Both patients had clinical manifestations of chronic GVHD (cGVHD), which were followed by dyspnea and cough without fever 120 days (case 1) or 100 days (case 2) after BMT. Abnormal lung function tests and radiographic infiltrates indicated that patients developed IP, but causative microorganisms could not be detected in the bronchoalveolar lavage (BAL) specimens. Subjective symptoms disappeared in a few days after administering PSL (1mg/kg/day). Laboratory data also improved thereafter. These observations, including the development of radiographic infiltrates along with clinical manifestations of cGVHD, absence of febrile episodes, absence of causative microorganisms in the BAL specimens, and effectiveness of immunosuppressive drugs, suggested that idiopathic IP observed in our cases might be a manifestation of cGVHD.

Adult↗
PubMed1992

Transfer RNA genes in the mitochondrial genome from a liverwort, Marchantia polymorpha: the absence of chloroplast-like tRNAs.

Twenty-nine genes for 27 species of tRNAs were deduced from the complete nucleotide sequence of the mitochondrial genome from a liverwort, Marchantia polymorpha. One to three species of tRNA genes corresponded to each of 20 amino acids including three species for leucine and arginine, two species for serine and glycine, and one for the rest of the amino acids. Interestingly, all tRNA genes were located in the semicircle of the liverwort mitochondrial genome except for the trnY and trnR genes. The region containing these tRNA genes was originally duplicated, and two trnR genes have diverged from each other. On the other hand, trnY and trnfM are present as two identical copies. The G:U and U:N wobbling between the first nucleotide of the anticodon and the third nucleotide of the codon permit the 27 tRNA identified species to translate almost all codons. However, at least two additional tRNA genes, trnl-GAU for AUY codon and trnT-UGU for ACR codon, are required to read all codons used in the liverwort mitochondrial genome. All of the identified tRNA genes are 'native' in liverwort mitochondria, not 'chloroplast-like' tRNAs as are found in the mitochondria of higher plants. This result implies that the tRNA gene transfer from chloroplast to mitochondrial genome in higher plants has occurred after the divergence from bryophytes.

Base Sequence↗
PubMed1992

Gene clusters for ribosomal proteins in the mitochondrial genome of a liverwort, Marchantia polymorpha.

We detected 16 genes for ribosomal proteins in the complete sequence of the mitochondrial DNA from a liverwort, Marchantia polymorpha. The genes formed two major clusters, rps12-rps7 and rps10-rpl2-rps19-rps3-rpl16-rpl5- rps14-rps8- rpl6-rps13-rps11-rps1, very similar in organization to Escherichia coli ribosomal protein operons (str and S10-spc-alpha operons, respectively). In contrast, rps2 and rps4 genes were located separately in the liverwort mitochondrial genome (the latter was part of the alpha operon in E. coli). Furthermore, several ribosomal proteins encoded by the liverwort mitochondrial genome differed substantially in size from their counterparts in E. coli and liverwort chloroplast.

Amino Acid Sequence↗
PubMed1992

Granulocyte colony-stimulating factor receptors on human acute leukemia: biphenotypic leukemic cells possess granulocyte colony-stimulating factor receptors.

Granulocyte colony-stimulating factor (G-CSF) receptors on the gated leukemic blast cells from newly diagnosed patients with acute leukemia or crisis of chronic myelogenous leukemia were investigated using flow cytometric detection. Surface marker analysis and cytochemical studies were conducted simultaneously to characterize the blast cells. Among 24 leukemia cases examined, G-CSF receptor-positive blast cells were detected in all 11 cases of acute myeloblastic leukemia even though the percentage range of positive cells was widely variable. On the other hand, they were not detected on the blast cells from patients with peroxidase-negative acute lymphoblastic leukemia with no myeloid surface antigens. However, G-CSF receptors were demonstrated in significant amounts on blast cells from 5 of 8 cases of peroxidase-negative acute leukemia expressing both myeloid and lymphoid surface antigens (biphenotypic leukemia). The percentage of blast cells positive for G-CSF receptors was significantly smaller in biphenotypic cases [33 +/- 14% (SD)] than in acute myeloblastic leukemia cases [65 +/- 22%] (P less than 0.01). The percentage expression of CD13 antigen by blast cells was significantly related to their percentage positivity for G-CSF receptors (rs = 0.50, P less than 0.05). These findings indicate that the distribution of flow cytometrically detectable G-CSF receptors on leukemic cells possessing myeloid characteristics may be related to the maturation process.

Antigens, CD↗
PubMed1992

Gene organization deduced from the complete sequence of liverwort Marchantia polymorpha mitochondrial DNA. A primitive form of plant mitochondrial genome.

Analysis of the mitochondrial DNA of a liverwort Marchantia polymorpha by electron microscopy and restriction endonuclease mapping indicated that the liverwort mitochondrial genome was a single circular molecule of about 184,400 base-pairs. We have determined the complete sequence of the liverwort mitochondrial DNA and detected 94 possible genes in the sequence of 186,608 base-pairs. These included genes for three species of ribosomal RNA, 29 genes for 27 species of transfer RNA and 30 open reading frames (ORFs) for functionally known proteins (16 ribosomal proteins, 3 subunits of H(+)-ATPase, 3 subunits of cytochrome c oxidase, apocytochrome b protein and 7 subunits of NADH ubiquinone oxidoreductase). Three ORFs showed similarity to ORFs of unknown function in the mitochondrial genomes of other organisms. Furthermore, 29 ORFs were predicted as possible genes by using the index of G + C content in first, second and third letters of codons (42.0 +/- 10.9%, 37.0 +/- 13.2% and 26.4 +/- 9.4%, respectively) obtained from the codon usages of identified liverwort genes. To date, 32 introns belonging to either group I or group II intron have been found in the coding regions of 17 genes including ribosomal RNA genes (rrn18 and rrn26), a transfer RNA gene (trnS) and a pseudogene (psi nad7). RNA editing was apparently lacking in liverwort mitochondria since the nucleotide sequences of the liverwort mitochondrial DNA were well-conserved at the DNA level.

Base Sequence↗
PubMed1992

Folinic acid does not mobilize hemopoietic progenitors following repeated consolidation chemotherapy for acute leukemia.

Folinic acid (FA) has been reported to expand the pool of peripheral blood stem cells (PBSC) after chemotherapy. We evaluated the efficacy of FA for harvesting PBSC following cytotoxic chemotherapy in 4 patients with acute leukemia. After achieving a complete remission (CR), 3 courses of chemotherapy for a consolidation of the CR were administered to the patients. Two successive cycles of leukapheresis were performed during the recovery phase from consolidation chemotherapy, which consisted of an intermediate dose of cytosine arabinoside. For the second cycle of leukapheresis, FA was administered intravenously at a dose of 50 mg/day following consolidation. The yields of either mononuclear cells or burst-forming units-erythroid (BFU-E) were not affected by FA administration. In contrast, the yields of colony-forming units-granulocyte/macrophage (CFU-GM) were significantly decreased in all patients compared to the CFU-GM yields after the first cycle of leukapheresis (P = 0.032). Thus FA is considered not to be effective in expanding the peripheral blood progenitor pool when given in a fashion different from the original report.

Acute Disease↗
PubMed1992

Continuous and simultaneous ultrasound Doppler velocimetry of the internal carotid and vertebral arteries: preliminary observations of cerebral blood flow changes with common carotid compression.

We have developed a new technique for simultaneous assessment of the four cervical cerebral arteries. Using a cervical brace with four freely adjustable Doppler probes attached, we studied four healthy young males and observed their cerebral blood flow changes during common carotid compression. The results indicated various reactivity in these subjects. We observed that carotid compression sometimes affects or stops the ipsilateral vertebral flow according to the intensity and location of compression. Also, the flow of the contralateral internal carotid artery (ICA) and vertebral artery (VA) showed remarkable increases greater than those due to ICA obliteration alone. This indicates the possibility that using only one probe during compression may often result in unknown obliteration of the ipsilateral VAs flow and could also produce other incomplete data. Moreover, with our technique, we would be able to assess the cerebral reserve more precisely and clearly in patients with carotid or vertebral occlusive diseases.

Adult↗
PubMed1992

Biological characteristics of CD7 positive acute myelogenous leukaemia.

We studied the biological characteristics of CD7+ acute myelogenous leukaemia (AML). We diagnosed nine out of 88 consecutive AML cases as CD7+ AML based on myeloperoxidase positivity and surface antigen expression. In eight of these nine cases more than 20% of leukaemic blasts were found to coexpress both CD7 and a myeloid-associated antigen, CD33, by a two-colour flow-cytometric assay, while in the remaining case more than 90% of blasts were positive for CD7 and myeloperoxidase. CD7+ AML was most frequently observed in M1 among AML subtypes according to the FAB classification. An early stage-specific antigen, CD34 was also expressed on leukaemic blasts from eight of these nine cases. Neither the T-cell receptor (TcR)-beta nor the TcR-gamma gene was clonally rearranged in any of the cases. We then studied the proliferative responses to stimulation by various growth factors. Among interleukin-3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF), and granulocyte-CSF (G-CSF), IL-3 showed the strongest stimulatory effect on DNA synthesis and leukaemic blast colony formation in 8/9 and 6/8 CD7+ AML cases examined, respectively. On the other hand, the strongest stimulatory effect exerted by IL-3 on blast colony formation was observed in only six out of the 33 CD7- AML cases examined. Furthermore, CD7+ AML blasts could proliferate in response to stem cell factor (SCF); SCF alone showed stimulatory effects on blast colony formation (7/8 cases), and in 5/7 SCF-responding cases, stimulatory effects of SCF were more potent than those of IL-3. In addition, SCF enhanced blast colony formation synergistically with IL-3 in four of these seven cases. These data suggest that progenitor cells of CD7+ AML may possess the biological properties characteristic of immature haematopoietic stem cells.

Adolescent↗
PubMed1992

Interstitial 9q deletion in T-lymphoid/myeloid biphenotypic leukaemia.

We report the biological characteristics of leukaemic blasts from two cases of acute leukaemia with an interstitial deletion of the long arm of chromosome 9 (9q-). Case 1 (FAB: M1) showed del(9)(q12q22) as the sole karyotypic anomaly, and case 2 (FAB: M1) presented del(9) (q12q22) in association with trisomy 10. In both cases, leukaemic blasts presented unique cytological features, such as prominent vacuoles on Giemsa staining, or strong localization of myeloperoxidase resembling 'pseudo-Chediak-Higashi' granules. Immunophenotyping of blasts revealed the biphenotypic expression of T-lymphoid/myeloid antigens (CD2, CD7/CD33) in addition to CD34. Neither T-cell receptor beta (TCRB), T-cell receptor gamma (TCRG) nor Ig heavy chain (IGH) genes were clonally rearranged. Furthermore, there was neither rearrangement nor expression of ABL, which is located at 9q34, indicating that the deletion involved bands centrometric to 9q34 did not induce the activation of ABL. DNA synthesis of the blasts was stimulated (stimulation index greater than 2.0) in the presence of interleukin (IL)-3, IL-4, granulocyte colony-stimulating factor or erythropoietin (Epo). IL-3 and IL-4 could also support the in vitro growth of leukaemic blast colonies, and the IL-3- or IL-4-dependent blast colony growth was synergistically enhanced by the addition of IL-6 or Epo. These observations imply that T-lymphoid/myeloid or pluripotent stem cells may be closely involved in the development of 9q- AML.

Adolescent↗