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61.
Yamamoto K Ito M Minagawa K Urahama N Sada A Okamura A Matsui T 《Cancer Genetics and Cytogenetics》2005,162(2):160-165
Deletions or translocations of chromosome band 13q14, the locus of the retinoblastoma gene (RB1), have been observed in a variety of hematological malignancies including myelodysplastic syndrome (MDS). We describe here a novel unbalanced translocation der(13)t(7;13)(p13;q14) involving 13q14 in a patient with MDS. A 66-year-old woman was diagnosed as having MDS, refractory anemia with excess of blasts (RAEB-1) because of 7.4% blasts and trilineage dysplasia in the bone marrow cells. G-banding and spectral karyotyping analyses showed complex karyotypes as follows: 46,XX,der(6)t(6;7)(q11;?),der(7)del(7)(?p13)t(6;7)(q?;q11)t(6;13)(q?;q?),der(13)t(7;13)(p13;q14). Fluorescence in situ hybridization (FISH) analyses demonstrated that one allele of the RB1 gene and the microsatellite locus D13S319, located at 13q14 and telomeric to the RB1 gene, was deleted. Considering other reported cases, our results indicate that submicroscopic deletions accompanying 13q14 translocations are recurrent cytogenetic aberrations in MDS. The RB1 gene or another tumor suppressor gene in the vicinity of D13S319, or both, may be involved in the pathogenesis of MDS with 13q14 translocations by monoallelic deletion. 相似文献
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Production of heavy-chain class-switch variants of human monoclonal antibody by recombinant DNA technology
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S Komori N Yamasaki M Shigeta S Isojima T Watanabe 《Clinical and experimental immunology》1988,71(3):508-516
We have previously established a human-mouse heterohybridoma (H6-3C4), which produced a human sperm-immobilizing antibody (mu, lambda of human type). The human rearranged immunoglobulin mu-chain and lambda-chain genes were cloned from the hybridoma H6-3C4. The cloned V region of the heavy chain (VH) gene was ligated to human immunoglobulin gamma 1-heavy chain constant region (C gamma 1) genes. This resulted in the heavy-chain class-switch from mu-chain to gamma 1-chain of H6-3C4 antibody. The class-switched heavy-chain gene as well as the cloned lambda-chain gene were introduced into mouse myeloma cell line X63Ag8.653 by protoplast fusion and electroporation. The stable transformants produced the human IgG monoclonal antibody, which fully retained specificity to human sperm cells and sperm-immobilizing activity. 相似文献
66.
Masahiro Yamasaki 《Developmental dynamics》1990,188(3):249-259
The thyroid and thymic arteries were investigated in 50 male and 50 female rats. In more than 70% of the animals, on both sides the cranial thyroid artery forms a common trunk with the ascending pharyngeal artery. The caudal thyroid artery arises not from the deep cervical but from the pericardiacophrenic artery. It may be replaced, however, by a branch of some other artery, such as the brachiocephalic, subclavian, vertebral, or ascending cervical, suggesting a shift of its origin from the internal thoracic artery to the thyrocervical trunk as in man. All the thoracic lobes of the thymus are supplied directly by a thymic branch of the internal thoracic artery or indirectly by a branch of the pericardiacophrenic artery. More than half of the specimens have a cervical thymic lobe of variable size, which is supplied by a branch of the cranial thyroid, external carotid, and/or occipital arteries. Some of these thymic arteries, except those from the external carotid and occipital arteries, reach the thoracic lobe. The thoracic lobes lacking a cervical lobe may be supplied by the thymic branch arising only from the cranial thyroid artery. Other anomalous arteries supplying the thoracic lobe are derived from the superficial cervical and/or the right common carotid arteries. These results show that the thymic arteries of rats are basically similar to those of man, although they display a clear difference in their frequency and origin. 相似文献
67.
Matsushita M Tanaka A Kikuchi K Kitazawa E Kawaguchi N Kawashima Y Kato T Fujikawa H Quaranta S Rosina F Gershwind ME Miyakawa H 《Autoimmunity》2002,35(8):531-536
Several lines of data suggest that genetic factors play an important role in the onset and/or progression of primary biliary cirrhosis (PBC). Since PBC is an autoimmune disease, it is reasoned to assume that genes encoding cytokines may confer susceptibility to disease. Amongst these factors, interleukin-10 (IL-10) has received significant attention. The promoter region of IL-10 gene has three single nucleotide polymorphisms (SNPs) at positions -1082, -819 and -592. To elucidate the association of the three SNPs of IL-10 promoter region with susceptibility of PBC in two different genetic populations, 159 unrelated patients with PBC (94 Italian and 65 Japanese) and 143 local controls (72 Italian and 71 Japanese) were enrolled. SNPs were determined using allele-specific PCR/RFLP. In Italian PBC patients, the frequency of homozygosity for G/G at position -1082 was significantly higher than that of local controls (p < 0.041, OR = 2.44, 95% C.I.; 1.02-5.86). The frequencies of haplotype GCC in PBC patients, possibly linked to higher IL-10 production, were also significant higher than local controls (p < 0.033). However, in Japanese population, there were no significant differences in the three SNPs and haplotypes between PBC patients and controls. Excessive production of IL-10 may play an important role in some populations in modulating the onset of PBC. Further, immunogenetic studies of PBC should take into account ethnic and geographic variations; this makes such studies in heterogeneous population, like the USA, more difficult. 相似文献
68.
Characteristics of the antihistamine effect of TAK-427, a novel imidazopyridazine derivative 总被引:1,自引:0,他引:1
S. Fukuda K. Midoro M. Yamasaki M. Gyoten Y. Kawano H. Fukui Y. Ashida H. Nagaya 《Inflammation research》2003,52(5):206-214
OBJECTIVE AND DESIGN: The characteristics of the antihistamine effect of the new antiallergic compound TAK-427 were investigated. MATERIALS AND METHODS: In vitro binding assay of [(3)H] pyrilamine was performed using recombinant human histamine H(1) receptors (rhH(1)R). In vivo studies were performed in male ICR mice or Hartley guinea pigs. Drugs were administered orally 1 h before examinations. Determinations were made of histamine-induced skin reaction, ex vivo measured radioligand binding to brain and lung H(1) receptors, pentobarbital-induced sleeping time, passive cutaneous anaphylaxis (PCA) reaction, and antigen-induced itch-scratch responses (ISRs). RESULTS: TAK-427 inhibited ligand binding to rhH(1)R with an IC(50) value of 17.3 nmol/l. TAK-427 inhibited histamine-induced skin reactions in guinea pigs and mice with an ID(50) value of 0.884 and 0.450 mg/kg, p.o., respectively; significant inhibition associated with 10 mg/kg of TAK-427 was still observed 24 h after dosing in guinea pigs. TAK-427 showed as high selectivity for peripheral H(1) receptors as terfenadine and epinastine did, which was evaluated by ex vivo measured radioligand binding. Even at 300 mg/kg, TAK-427 did not affect pentobarbital-induced sleeping time in mice. TAK-427 significantly inhibited PCA in mice and guinea pigs, and also inhibited antigen-induced ISRs in guinea pigs. CONCLUSIONS: These results suggest that TAK-427 may have a long-lasting antihistamine activity with minimum sedative side effect and suppress acute phase allergic reactions. 相似文献
69.
The kinetics of IgE-mediated release of serotonin from passively sensitized rat mast cellsin vitro was studied by stopping14C-serotonin release with the application of formaldehyde fixative or ice-cold mast cell medium (MCM). Antigen dose-release curves of14C-serotonin and/or histamine were comparable when mediator release was terminated with either formaldehyde at a final concentration of 1% or ice-cold MCM 15 min after antigen challenge. However, the kinetic study of immunological mediator release stopped by formaldehyde showed that the addition of antigen resulted in a progressive increase of released14C-serotonin for 7 min, the release curve being sigmoidal, whereas the application of ice-cold MCM artificially enhanced14C-serotonin and histamine release in the first 2 min. The results suggest that stopping IgE-mediated release of14C-serotonin with formaldehyde is a simple, rapid and accurate method of studying the kinetics of mediator release from mast cells. 相似文献
70.
A. M. Albisser Y. Yamasaki H. Broekhuyse J. Tiran 《Annals of biomedical engineering》1980,8(4-6):539-557
A hypercomplex circulation and organs model of glucose and insulin dynamics is presented. The model is based on physiological
parameters, incorporating blood and plasma flow rates, circulatory paths, intra- and extravascular glucose and insulin spaces,
as well as the specific organs and tissues involved both with insulin disappearance and with glucose production or uptake.
Its simulations readily lend themselves to physiological interpretation. To explore its validity, the model was assigned parameters
typical of a 12 kg dog and was arranged to accept known glucose and insulin infusions from two different experiments on pancreatectomized
diabetic animals. It predicted the observed glucose and insulin concentrations as well as uptake rates for both moieties in
the individual organs and tissues. This confirmed the ability of the model to predict with consistency the group mean outcomes
of both experiments when differing routes (portal or peripheral) of infusion were applied. Excellent agreement was achieved
for the studies. The model isolates glucose uptake in the periphery, the liver, the brain, and the gut and allows a direct
comparison of glucose disposal along various routes. Thus, the total amount of glucose uptake by peripheral, insulin-dependent
tissues is directly calculated to be 30% of an intravenous glucose load, with peripheral infusion, which is higher than that
with portal infusion (18%).
This investigation was conducted as a project of the Artificial Pancreas Programme and is supported in part by a grant MA5767
from the Medical Research Council of Canada and a negotiated contract No. NO1-AM-9-2201 from The National Institutes of Health,
Bethesda, Maryland. 相似文献