PubMed Health⌕ Search

Biomedical subjects

T Komeno

Publications and source records attributed to T Komeno.

32 records · Page 2Linked to original sources
PubMed1996

Disseminated nontuberculous mycobacteriosis caused by mycobacterium kansasii in a patient with myelodysplastic syndrome.

A 38-year-old man with pancytopenia due to myelodysplastic syndrome exhibited persistent pyrexia and mediastinal lymphadenopathy. A biopsy specimen of the lymph nodes showed diffuse infiltration of epitheloid cells, including acid-fast bacilli identified as Mycobacterium kansasii. Cultures from gastric lavage and stool yielded M. kansasii, and granulomas were found in the bone marrow. A diagnosis of disseminated nontuberculous mycobacteriosis (DNTM) was established. The patient's condition improved after treatment with isoniazid, rifampicin, ethambutol and granulocyte colony-stimulating factor. Although DNTM due to M. kansasii is rare in Japan, it should be recognized as a possible cause of opportunistic infections.

Adult↗
PubMed1996

Hemolytic anemia associated with myotonic muscular dystrophy.

Hemolytic anemia developed in a male who had been diagnosed as having myotonic muscular dystrophy (MMD). His red cell life-span examined by 51Cr-labeling method was shortened (T 1/2 = 6.5 days). Specific abnormalities of red cells were not found other than increased osmotic resistance, increased intracellular sodium, and decreased intracellular potassium of red cells. A clinical review of 18 other patients with MMD did not reveal any signs of hemolysis. It may be suggested that the underlying red cell membrane defects due to MMD contributed to this rare association with hemolysis.

Anemia, Hemolytic↗
PubMed1996

[Homozygous beta(+)-thalassemia due to -31 A to G mutation].

A 20-year-old Japanese woman was admitted to our hospital with anemia and mild splenomegaly. Peripheral blood examination revealed Hb 9.4 g/dl, Ht 29.3%, RBC 4.74 x 10(6)/microliters, reticulocytes 2.4%, WBC 5,200/microliters, platelets 24.9 x 10(4)/microliters, MCV 61.7 fl, and MCH 19.9 pg. Poikilocytosis with target cells was recognized on the peripheral blood smear. A bone marrow aspirate revealed erythroid hyperplasia. Serum iron and ferritin were in the normal range. beta-thalassemia was suggested by the increase in HbA2 (6.5%) and HbF (7.5%). Analysis of beta globin DNA by single strand conformation polymorphism (SSCP) and amplification refractory mutation system (ARMS) confirmed a diagnosis of homozygous beta(+)-thalassemia due to -31 A to G mutation. A familial study revealed that her parents were heterozygous for this allele. This is the 8th case of homozygous beta(+)-thalassemia due to -31 A to G mutation in Japan.

Adult↗
PubMed1996

[Appearance of cytoplasmic processes of megakaryocytes in the peripheral blood in a Munchausen syndrome with factitious anemia].

Many cytoplasmic processes of megakaryocytes were seen in a 45-year-old male patient of Munchausen syndrome with sustained severe anemia due to repeated self-blood drawing. He had a past history of repeated infection and removal of skin-graft transplanted for giant congenital melanocytic nevus due to self-infliction (later confessed by the patient). On the admission, he presented with high fever (39 approximately 40 degrees C) and severe sustained anemia refractory to repeated blood transfusions. Any specific clinical data indicating bleeding or hemolysis were not found. Self-blood drawing was discovered by a nurse on his 27th hospital day. Syringes and needles for blooddrawing were also found. He recovered from anemia under intensive watching without any specific treatment. He confessed that the high fever was artificial. It was of interest that cytoplasmic processes of megakaryocytes were seen in the peripheral blood film until he recovered from anemia for one month. The serum level of erythropoietin was elevated (1540 mU/ml), but not significantly was that of thrombopoietin (1.54 fmol/ml). This case was considered to be valuable to understand the mechanism of platelet-production by megakaryocytes at persistent bleeding.

Anemia↗
PubMed1995

Megakaryopoiesis in patients with cyclic thrombocytopenia.

Megakaryopoiesis was examined in 10 patients (eight females and two males) with cyclic thrombocytopenia (CT) to investigate the underlying pathogenesis. Numbers of CFU-Meg and megakaryocytes and the mean cytoplasmic area (mean area) of megakaryocytes at the peak, nadir, ascent mid phase, and descent mid phase of the platelet cycle were determined. The patients were classified as female cases group I (cases 1-4; previously diagnosed as ITP and CT occurred during remission), female cases group II (cases 5-8; persistent CT from initial diagnosis), and male CT (cases 9 and 10). In three of the four female cases in group I, numbers of CFU-Meg and megakaryocytes were normal or increased persistently during the platelet cycle, whereas the mean area fluctuated in synchrony with the platelet cycle, suggesting failure of cyclic production rather than platelet destruction. In the female cases in group II and one female case in group I, numbers of CFU-Meg and megakaryocytes were also normal or increased at four phases of the cycle, but the mean area did not fluctuate, remaining large during the cycle, suggesting cyclic destruction or platelet clearance. In contrast, in the male patients values for numbers of CFU-Meg, megakaryocytes and mean cytoplasmic area fluctuated during the platelet cycle, indicating that cyclic changes in megakaryopoiesis generated the platelet cycle. These findings indicate that the measurement of cytoplasmic area is useful for distinguishing cyclic platelet production from cyclic destruction or clearance in CT.

Adult↗
PubMed1995

Effects of anti-platelet glycoprotein Ib and/or IIb/IIIa autoantibodies on the size of megakaryocytes in patients with immune thrombocytopenia.

To determine whether anti-platelet autoantibodies react with megakaryocytes, as well as with platelets, in immune thrombocytopenia (ITP), 38 ITP patients were studied. They were classified into four groups; anti-platelet glycoprotein Ib-positive (group A, n = 5), anti-platelet glycoprotein II/b/IIIa-positive (group B, n = 2), positive to both antibodies (group C, n = 3), and negative to both antibodies (group D, n = 28). The number and size of megakaryocytes in each group were compared. The number of megakaryocytes in groups A, B, C, and D was 12.8 +/- 8.9, 75.2, 29.1, and 17.0 +/- 21.7/mm2, respectively. The mean cytoplasmic area of megakaryocytes in groups A, B, C, and D was 1001 +/- 26.3, 1621, 1109, and 1311 +/- 235.6/micrograms2, respectively. This finding indicated that, in the presence of anti-platelet glycoprotein Ib, megakaryocytes were not increased in number and were small in size, whereas, in the presence of anti-platelet glycoprotein IIb/IIIa, megakaryocytes were increased in number and in cytoplasmic area. Our study suggested that anti-platelet glycoprotein Ib may impair platelet production by megakaryocytes in ITP.

Antibody Specificity↗
PubMed1995

Simultaneous measurements of megakaryocyte-associated IgG (MAIgG) and platelet-associated IgG (PAIgG) in chronic idiopathic thrombocytopenic purpura.

We have simultaneously measured platelet-associated IgG (PAIgG) and megakaryocyte-associated IgG (MAIgG) in 30 untreated patients with chronic idiopathic thrombocytopenic purpura (CITP). Megakaryocytes were purified from bone marrow by 35% Percoll gradient centrifugation, followed by negative immunopanning using magnetic immunobeads. The normal range of MAIgG in 30 healthy donors was 15.5 +/- 10.0 ng/10(5) megakaryocytes, whereas MAIgG in the 30 CITP patients was 140 +/- 59.3 ng/10(5) megakaryocytes, although the values were widely distributed. From the PAIgG and MAIgG data, CITP patients were classified into three types; type I (PAIgG < 200 ng/10(7) platelets and MAIgG < 150 ng/10(5) megakaryocytes), type II (PAIgG > 200 ng and MAIgG > 150 ng), and type III (PAIgG < 200 ng and MAIgG > 150 ng). Patients with types I and III had good clinical courses, but, in contrast, patients with type II responded poorly to steroid therapy followed by splenectomy or became refractory to treatment. In splenectomized patients, MAIgG of responder was promptly decreased to normal range and, in contrast, that of non-responder was persistently elevated. These results indicate that anti-platelet autoantibodies are able to bind with megakaryocytes in the bone marrow as well as with platelets in the peripheral blood, and the results also suggest that megakaryopoiesis in CITP is heterogeneous. Simultaneous measurement of PAIgG and MAIgG may predict the clinical outcome of CIPT.

Autoantibodies↗
PubMed1995

CD34-positive blastoma in a patient with idiopathic myelofibrosis.

We report CD34-positive "blastoma" which developed in a patient with idiopathic myelofibrosis (IMF). A 48-year-old woman was diagnosed as having essential thrombocythemia, then the disease had transformed into IMF 41 months later. Finally, a subcutaneous tumor, composed of blastic cells positive for CD34 but negative for lineage-specific antigens, developed without any evidence of systemic leukemia transformation.

Antigens, CD34↗
PubMed1993

[Essential thrombocythemia in pregnancy].

A 30-year-old woman was admitted to our hospital because of thrombocythemia during pregnancy. Her leukocyte count was 10,000/microliters, Hb was 11.7 g/dl, and platelet count 181.9 x 10(4)/microliter. Bone marrow aspirate showed an increase in megakaryocytes (255/microliters). Both Ph1 chromosome and bcr rearrangement were negative. She was diagnosed as having essential thrombocythemia (ET) with pregnancy, and was treated with aspirin (150 mg/day). Her pregnancy was uneventful, but she was readmitted because of overterm pregnancy. A caesarean section was performed, and a healthy male infant weighing 3,672 g was delivered, with a platelet count of 25.5 x 10(4)/microliter. However, the uterine was atonic, and atonic hemorrhage occurred. Supravaginal hysterectomy was performed. Subsequently, intrabdominal gross hemorrhage occurred, but the bleeding was halved by platelet transfusion. Microscopic examination showed uterine infarction. We suggest that platelet count should be reduced by means of plateletpheresis or interferon-alpha throughout pregnancy with ET.

Adult↗
PubMed1987

Effect of latamoxef on platelet function and prothrombin time in partially nephrectomized rats.

Latamoxef (daily 100 and 300 mg/kg, i.v.) was injected once a day for 8 days to 75% and 90% nephrectomized rats kept on a vitamin K-sufficient diet (500-600 ng/g) or a vitamin K-deficient diet (30-50 ng/g), and changes in ADP-induced platelet aggregation and prothrombin time were examined. The half-life of latamoxef was markedly prolonged and plasma latamoxef and N-methyltetrazolethiol (NMTT) concentrations increased, resulting in a delay of the total body clearance of the compounds. The ADP-induced platelet aggregation increased after nephrectomy, and latamoxef slightly but inconsistently decreased the aggregation. Prothrombin time did not change even in the 90% nephrectomized rats kept on an ordinary diet, but increased dose-dependently in the vitamin K-deficient nephrectomized rats, with the 90% nephrectomized animals showing larger increases of prothrombin time. These data suggest that NMTT or NMTT-containing antibiotics cause no hypoprothrombinemia even in partially nephrectomized rats when they are fed an ordinary diet containing vitamin K, but these compounds enhance the manifestation of hypoprothrombinemia in vitamin K deficiency. Further renal failure promotes the manifestation by increasing drug concentration in the blood. However, platelet aggregation in these animals is not significantly affected at the doses examined.

Adenosine Diphosphate↗