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Biomedical subjects

Y Amano

Publications and source records attributed to Y Amano.

At least 109 records · Page 6Linked to original sources
PubMed1992

[Suppression of in vitro hemopoiesis by the monocytes in a patient with aplastic anemia associated with hepatitis].

The cause of aplastic anemia associated with hepatitis (AAH) is as yet still unknown. There is a supposed relation to the immune mechanisms, however few reports have shown the effects of monocytes on the pathogenesis in the patients with AAH. We have reported a case of a 12-year-old boy with AAH related to cytomegaloviruses, and studied the hemopoietic progenitors. He showed pancytopenia and hypoplasia of the bone marrow on admission to our hospital. The culture studies showed that mononuclear cells (MNC) of the bone marrow produced few hemopoietic colonies in all cell lineages. However, the depletion of adherent cells from the MNC increased numbers of erythroid, neutrophil-macrophage and megakaryocyte colonies. Furthermore, the addition of adherent cells of the peripheral blood suppressed the colony formation in the aforementioned cell lineages by marrow MNC from which adherent cells, phagocytic cells and T-cells were abrogated. The results way suggest that monocytes play some soles in the pathogenesis of aplasia through inhibitor of hemopoiesis.

Anemia, Aplastic↗
PubMed1991

Interleukin-6 supports human megakaryocytic proliferation and differentiation in vitro.

The effect of interleukin-6 (IL-6) on cells of human megakaryocyte (MK) lineage from cord blood was explored. In semisolid colony assays containing human plasma, a greater number of both MK colonies and cells per colony was seen in the presence of IL-6 and IL-3 than in the presence of IL-3 alone. This stimulatory effect of IL-6, observed on both small and large MK colonies, was completely eliminated by the addition of anti-IL-6 antibody to the culture. IL-6 alone had no effect on MK colony formation. In the primary culture, MKs showed larger cell size and DNA content in the presence of both IL-3 and IL-6 than IL-3 alone. The replating experiments using immature MKs grown in the presence of IL-3 showed that IL-6 significantly augmented both cell size and DNA content. This effect was also neutralized by an anti-IL-6 antibody. IL-3 had no tangible effect on MK differentiation. Synergism between IL-6 and IL-3 on MK differentiation was not confirmed. These results suggest that IL-6 is a synergistic factor in the proliferation of MK progenitors and a direct effector of differentiation of immature MKs on in vitro human megakaryocytopoiesis.

Cell Differentiation↗
PubMed1991

Hyoscyamine 6 beta-hydroxylase, an enzyme involved in tropane alkaloid biosynthesis, is localized at the pericycle of the root.

Hyoscyamine 6 beta-hydroxylase (H6H; EC 1.14.11.11) catalyzes the first reaction in the biosynthetic pathway from hyoscyamine to scopolamine in several solanaceous plants. Four monoclonal antibodies were raised against H6H purified from cultured roots of Hyoscyamus niger. The IgG1 antibody mAb5 inhibited H6H activities present in cell-free extracts of H. niger roots and specifically recognized 38-40-kDa proteins from six different scopolamine-producing plant species in Western blot analysis after sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. The other three monoclonal antibodies all recognized SDS-denatured H6H protein from Hyoscyamus species, but did not bind to native H6H. Western blot analysis of protein extracts from various tissues of H. niger using these antibodies showed that H6H is abundant in cultured roots, present in plant roots, but absent in leaf, stem, calyx, cultured cells, and cultured shoots. Immunohistochemical studies using monoclonal antibody and immunogold-silver enhancement detected H6H only in the pericycle cells of the young root in several scopolamine-producing plants. Mature roots that underwent secondary growth and lacked the pericycle did not react with the antibody. This pericycle-specific localization of scopolamine biosynthesis provides an anatomical explanation for the tissue-specific biosynthesis of tropane alkaloids and may be important for translocation of tropane alkaloids from the root to the aerial parts.

Antibodies, Monoclonal↗
PubMed1991

Hereditary high-potassium erythrocytes with high Na, K-ATPase activity in Japanese shiba dogs.

The sodium (Na) and potassium (K) concentrations and Na, K-ATPase activity were examined in erythrocytes from 24 Japanese shiba dogs and 79 dogs of 24 other breeds. Eleven of the shibas had erythrocytes with high K and low Na concentrations, together with high Na, K-ATPase activity (HK RBCs), while red cells from the remaining shibas and all of the other breeds examined showed low K and high Na concentrations, with no enzyme activity (LK RBCs). The concentration of reduced glutathione in HK RBCs was about five times that in LK RBCs. All the findings from HK shibas were in good agreement with those from HK mongrel dogs found in Japan previously. Since the shiba is a Japanese breed of dog, the results of the present study strongly suggest that the gene for HK RBCs may be inherent in dogs indigenous to Japan, particularly in shiba dogs.

Animals↗
PubMed1991

Syntheses of 5,7,8- and 5,6,7-trioxygenated 3-alkyl-3',4'-dihydroxyflavones and their inhibitory activities against arachidonate 5-lipoxygenase.

5,6,7- and 5,7,8-Trioxygenated 3',4'-dihydroxyflavones were derivatized by introducing alkyl groups of various chain lengths at the 3-position of the flavone skeleton. These compounds were tested as inhibitors for arachidonate 5-lipoxygenase purified from porcine leukocytes. Modification of the 3-position with an alkyl group of 6-10 carbons markedly decreased the IC50 values. 3-Hexyl-3',4'-dihydroxy-5,7, 8-trimethoxyflavone inhibited 5-lipoxygenase with an IC50 value of 58 nM. The platelet and leukocyte 12-lipoxygenases, 15-lipoxygenase of reticulocytes, and cyclooxygenase of vesicular gland were inhibited less potently (IC50 = 0.4, 0.4, 2.7, and 30 microM). Thus, the compound was a relatively selective inhibitor for 5-lipoxygenase.

Animals↗
PubMed1991

[Epidemiological study on Chlamydia trachomatis infection in obstetrics and gynecology field in Tokyo].

In conjunction with the Tokyo Branch of Japan Association for Maternal Welfare, we have been carrying out examinations of Chlamydial infection on women, especially pregnant women, living in Tokyo. Specimens were collected from 212 gyneco-obstetric clinics in Tokyo during 4 years from January 1987-December 1990. A total of 13,925 swab specimens from patients who were suspected of sexually transmitted diseases from clinical findings and pregnant women who requested the examination were tested for the presence of antigen to C. trachomatis with EIA (Chlamydiazyme). Epidemiological analysis based on the results and case cards that were described sex, age, occupation and clinical findings were conducted. The results obtained are briefly summarized as follows. 1) C. trachomatis antigen was detected in 12.8% (1,237/9,657) of the female patients, 31.0% (124/400) of the male patients and 6.8% (10/168) of the infants. The detection rates of C. trachomatis antigen in the male patients was significantly higher than that in the female and the infants patients. C. trachomatis antigen was detected in 6.1% (226/3,683) of pregnant women. 2) The detection rates of C. trachomatis antigen were compared by occupation of female patients. Most high rate was 26.6% (53/199) in bar hostess , subsequently 20.1% (102/508) in students, 19.8% (59/298) in prostitutes, 13.6% (455/3,348) in office girls and 7.2% (471/6,573) in house-wives. It was noteworthy that the detection rates of C. trachomatis antigen in students was as similarly high as that in prostitutes. 3) The detection rates of C. trachomatis antigen was also compared by age groups. The detection rate had a tendency to be high in younger people.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

[Usefulness of the mailed specimens for mass examination of Chlamydia trachomatis and Neisseria gonorrhoeae with EIA].

The infections with C. trachomatis and N. gonorrhoeae have recently been determined routinely with the commercial kits for detecting the antigens of these organisms in both the clinical and mass examination laboratories. In mass examination, a change during transporting the specimens must be avoided. Hence, a study on whether the antigens were changed with atmospheric temperature was carried out. As for C. trachomatis, no change in antigen was found on the enzyme immunoassay (EIA) absorbance of the antigen quantity corresponding to the cell of 4.8 x 10(4), 2.4 x 10(4) and 6.0 x 10(3) (IFU/ml) until 5 days at 4, 25 and 37 degrees C respectively after sampling. The coefficient variation was found out to be ca. 10%. In a test on antigen stability of N. gonorrhoeae, similar results to that of C. trachomatis were obtained on the following antigen quantity: 2.4 x 10(3), 3.3 x 10(2) and 9.0 x 10 (CFU/ml) under the same conditions as in the above. The coefficient variation was found out to be 10% or less. To investigate whether there is any difference on the stability of C. trachomatis antigen between mailing and hand carrying, a total of 133 specimens collected from many clinics were subjected to the detection of antigen with the commercial EIA kits. The results of comparison on both transport methods were as follows: agreement rate 96.2%, positive rate 100% and negative rate 95.2%. The highly correlation between the both transportation was confirmed in the detection of antigen; that is, Y = 1.03X + 0.03, r = 0.936.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Bacterial↗
PubMed1991

[Three cases of psittacosis].

Case 1 was a 55 year old female whose primary complaint was pyrexia. Anamnesis consisted of a fever at a 39 degrees C level beginning on September 15, 1987 with headache and muscle pain. The patient was examined by a nearby physician. Despite taking medication, there was no break in the fever. The patient was examined and admitted to this institution on September 18. Case 2 was a 32 year old female whose primary complaint was pyrexia and an abnormal sensation in the pharynx. Anamnesis consisted of a fever at a 39 degrees C level beginning on February 13, 1989 and the manifestation of a cough beginning on February 17. Although the fever broke on February 20, as the abnormal sensation in the pharynx persisted, the patient was examined and admitted to this institution on February 21. Case 3 was a 42 year old male whose primary complaint was pyrexia. Anamnesis consisted of a fever of 38 degrees C, cough and a sensation of pressure in the right precordia beginning on November 18, 1989. The patient was examined and admitted to this institution on November 21. Chest X-rays revealed the presence of atypical pneumonia in all three cases. As a significant rise in antibodies to the Chlamydia of parrot fever was observed in the cases at the time of admittance as well as after admittance, treatment was begun by administration of Minocycline.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Antibiotic sensitivity and serotypes of group A hemolytic streptococci isolated from clinical specimens and healthy pupils in Japan, 1986-1988].

As an epidemiological survey for streptococcal infection, antibiotic sensitivity test and T-serotyping were made on 2,735 strains of group A hemolytic streptococci isolated from clinical specimens and healthy pupils between 1986 through 1988 in Japan. Most dominant serotype in clinical isolates was T-4 (26.8%) and it was followed T-12 (25.5%), T-1 (11.2%) and T-3 (8.5%), on the other hand, dominant serotypes of the isolates from healthy pupils were T-12 (30.4%), T-1 (19.3%), T-4 (15.3%) and T-28 (13.4%). All of the isolates tested were sensitive to the beta-lactam antibiotics which was found as same as consequence of the previous surveys. However 36.4% to tetracycline, 2.1% to chloramphenicol and 1.4% to oleandomycin of the clinical isolates were resistant. Similarly, 16.2% to tetracycline, 2.3% to chloramphenicol 1.7% to oleandomycin, of the isolates from healthy pupils were resistant. Multi-resistant strains were found 1.4% in clinical isolates and 1.7% in the isolates from healthy pupils. Relation between distribution of multiresistant strain and T-serotypes was found. In T-12, multiresistant strains were encountered at a relatively high rate compared with other serotypes, representing 3.5% in clinical isolates and 5.6% in the isolates from healthy pupils. However this tendency was decreased than previous surveys, while incidence of tetracycline resistant strains in T-4 remained at high level, representing about 94% as same as in the past.

Adolescent↗
PubMed1991

Cryoglobulinemia in a horse.

Cryoglobulin was isolated from a horse which had glomerulo-nephritis and a history of swelling and skin ulcers of the limbs in the winter. The isolated cryoglobulin showed a single peak on a gel permeation chromatography column with an apparent molecular mass (Mr) of 180,000 which could be divided into two gamma bands by cellulose acetate electrophoresis. Immunoelectrophoretic analysis revealed that the cryoglobulin formed two precipitation lines with anti-horse IgG. Spur formation was observed when the cryoglobulin and the IgG purified from a normal healthy horse were cross-reacted with anti-horse IgG on a double diffusion gel. In addition, sodium dodecyl sulfate-polyacrylamide gel electrophoresis under the reduced conditions showed that the isolated cryoglobulin consisted of two doublets of polypeptides with Mr values of 52,000 and 50,000, and 31,000, and 30,000, corresponding to the heavy chain and the light chain of the horse IgG molecules, respectively. These results suggest that the isolated cryoglobulin might consist of two different IgG molecules, and that the manifestations such as foot swelling with skin ulcers and renal failures were all induced by the cryoglobulin in the serum.

Animals↗
PubMed1991

[Bone marrow transplantation in a pediatric case of acute nonlymphocytic leukemia with hepatitis C].

An allogenic bone marrow transplantation (BMT) in an acute nonlymphocytic leukemia (ANLL) patient with post-transfusion hepatitis C is presented. A 13-year-old girl was admitted to our hospital on May 1988, and diagnosed as having ANLL M2 according to the FAB classification. During the induction and post-induction chemotherapy, 116 units of blood products were transfused to her as the supportive therapy until October 1988, when non-A non-B hepatitis developed. As the persistent liver dysfunction interfered with anti-leukemic chemotherapy on the protocol, allogeneic BMT from her HLA identical MLR nonreactive brother was done on July 1989. Preconditioning regimen consisted of busulfan and cyclophosphamide. GVHD prophylaxis consisted of cyclosporine A and short term methotrexate. After the BMT, her liver dysfunction once improved; her serum amino-transferase levels were normal for about 3 months. Soon after discontinuation of cyclosporine A, however, her liver function deteriorated again. The examination of hepatitis C virus antibody in her sera, which had been harvested sequentially and stored at -40 degrees C, on November 1989 revealed that she had been already seropositive at the time of BMT. The BMT-induced immunologic changes may have influenced the natural course of hepatitis C virus infection in the patient.

Adolescent↗
PubMed1991

[Marked bone marrow necrosis preceding acute myeloblastic leukemia in childhood].

A 3-year-old boy was transferred to our hospital because of fever, abdominal pain and severe systemic bone pain on October 16, 1989. Hematological examination showed hemoglobin 8.7 g/dl, white blood cell count 5300/microliters with 9% neutrophils and platelet count 5.5 x 10(4)/microliters. Bone marrow aspiration and biopsy revealed markedly necrotic cells. Blood chemistry showed transient elevation of CRP, serum LDH, FDP, FDP-Ddimer and fibrinogen. Tc99m pyrophosphate bone scanning showed multiple uptake spots in various bone. Although the sign of fever, abdominal pain and bone pain disappeared spontaneously after three weeks, anemia persisted. About two months later from bone marrow necrosis, abnormal cells appeared in the bone marrow. A diagnosis of AML (M3) was made and a combination chemotherapy started. This case is remarkable for elevation of acute phase protein in association with bone marrow necrosis.

Bone Marrow↗
PubMed1990

Two novel molecular isoforms of band 4.2 in Japanese Sika deer (Cervus nippon yesoensis, Heude) erythrocytes.

Two molecular isoforms of band 4.2 were identified in erythrocyte membranes from 25 Japanese Sika deer (Ceryus nippon yesoensis, Heude) based on specific immunorecognition with anti-human band 4.2. These two variants, designated 4.2/78 and 4.2/76, had respective relative molecular weights (Mr) of 78,000 and 76,000 on sodium dodecyl sulfate-polyacrylamide electrophoresis gels and showed similar profiles after limited proteolysis, exhibiting identity in primary structure. 25 adult Sika deer could be divided into two groups according to the 4.2/78:4.2/76 ration, indicating a genetic control in the expression of the molecular isoforms of band 4.2. Both polypeptides were completely retained in cytoskeletal protein-depleted membranes and could be removed by alkaline extraction, suggesting that both proteins contribute to the association of membrane proteins.

Animals↗
PubMed1990

[Comparison between two systems for assaying the level of antibody against Streptococcus agalactiae (GBS) type III].

Levels of antibody against GBS type III in pregnant women have been determined using ELISA assay method that we originally deviced. Toyo Jozo Co. have also introduced an assay system (the Toyo kit) that resembles ours. The present study was performed to compare our system with the Toyo kit. Correctivity between the two systems was good, giving a regression curve of Y = 1.18X - 0.60 and a correlation coefficient of r = 0.794. Antibody levels in pregnant women were determined by the Toyo kit, and were found to be less than 10 micrograms/ml in almost all samples. Among 19 serum samples from vaginal carriers of GBS type III, the antibody levels ranged from 1.5 to 93.8 micrograms/ml. Among seven maternal serum samples in cases of GBS type III infection, the maximum level was 6.0 micrograms/ml. Thus, the Toyo kit showed satisfactory sensitivity for determining the level of antibody against GBS type III. Hereafter, we intend to use the Toyo kit for determining antibody levels in pregnant women.

Antibodies, Bacterial↗
PubMed1990

[HLA antigens in 11 cases of patients with recurrent erythema and anti-SS-B antibody].

HLA antigens were studied in 11 cases of patients with recurrent erythema and anti-SS-B antibody. Among DR antigens positive associations with DR5, DRw6 (including DRw13), and DRw52 were obtained. These data demonstrated that 11 cases of this report are immunogenetically closely related to each other and appear to be related to Sjögren's/lupus erythematosus overlap patients.

Antibodies, Antinuclear↗
PubMed1990

[Colorimetric studies on hiding effect of Cosmotech porcelain for laminate restoration].

The hiding effect on color tone of discolored teeth restored with ceramic laminate veneer crown was examined. Translucent (T1, T2), Enamel (E1, E2, E3), Dentin (DA2, DA3, DB2, DB3), Masking dentin (MDA2, MDA3, MDB2, MDB3) in 13 colors and Modifire (M61, M62, M65, M66, M67, M68, M69, M70, M79) in 7 colors of the ceramic materials (Cosmotech porcelain G C Co., Ltd) were examined in this experiments. The colorimetric examination of the color tone backing with the white or black color was carried out by testing for color difference (delta E*ab), value difference (delta L*), chrom and hue of the samples. The result obtained were as follows; 1. Color difference was higher in order of T2 greater than T1 in Translucent greater than E1 greater than E3 greater than E2 in Enamel greater than DB3 greater than DA2 greater than DA3 greater than DB2 in Dentin greater than MDB3 greater than MDA2 greater than MDB2 greater than MDA3 in Masking dentin, and M69 greater than M79 greater than M70 greater than M68 greater than M66 greater than M61 greater than M62 greater than M67 greater than M65 in Modifire. 2. Value difference was higher in order of T2 greater than T1 in Translucent greater than E1 greater than E3 greater than E2 in Enamel greater than DB3 greater than DA2 greater than DB2 greater than DA3 in Dentin greater than MDA2 greater than MDB3 greater than MDB2 greater than MDA3 in Masking dentin, and M69 greater than M70 greater than M79 greater than M68 greater than M66 greater than M61 greater than M67 greater than M65 greater than M62 in Modifire.(ABSTRACT TRUNCATED AT 250 WORDS)

Adhesives↗