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Structural studies of a human gamma 3 myeloma protein (Jir) bearing the allotypic marker Gm(st) 总被引:2,自引:0,他引:2
H Matsumoto S Ito T Miyazaki T Ohta 《Journal of immunology (Baltimore, Md. : 1950)》1983,131(4):1865-1870
The authors established the amino acid substitutions determining G3m(s) and G3m(t) specificities, which characterize Mongoloid populations, by sequence analysis of the Fc region of a myeloma protein (Jir). By comparing the amino acid sequences of the IgG3 (Jir) and the other IgG subclasses analyzed to date, it was found that G3m(s) was an isoallotype specified by an amino acid substitution at position 435; i.e., whereas the subclasses IgG1, IgG2, and IgG4 had histidine in common, G3m(s-) had arginine in this position. This was also confirmed by the observation that the Fc fragment in question bound to protein A. It was also established that the amino acid at position 379 of G3m(t-) IgG3 and the other subclasses was valine, whereas methionine in this position was specific for G3m(t+). In addition, the amino acids at position 339 of G3m(u-) IgG3 Jir was threonine, and at position 296 of G3m(g-) IgG3 Jir was tyrosine. These findings are not in accord with the hitherto postulated relations of alanine and phenylalanine to G3m(u-) and G3m(g-), respectively. Finally, this study showed that a large number of substitutions occurred at positions 384 through 389, which suggests that many specificities of the G3m(b) group occur on IgG3 proteins. 相似文献
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K Miyazaki F Umenishi K Funahashi N Koshikawa H Yasumitsu M Umeda 《Biochemical and biophysical research communications》1992,185(3):852-859
Progelatinase A was purified as a complex with TIMP-2 from the conditioned medium of a human glioblastoma cell line. The TIMP-2/progelatinase complex was resistant to the activation by p-aminophenylmercuric acetic acid (APMA), and showed less than 10% of the activity of the TIMP-2-free active enzyme. When the complex was incubated with stromelysin in the presence of APMA, the 64-kDa progelatinase was effectively converted to the 57-kDa mature enzyme, increasing its gelatinolytic activity about 8-fold. These results suggest that stromelysin is a natural activator of TIMP-2-bound progelatinase A. 相似文献
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BACKGROUND: We report a successful pregnancy in a woman with severe ovarian dysfunction and infertility associated with a variant beta-subunit of luteinizing hormone (LH). METHOD/OUTCOME: A 35-year-old woman consulted our unit for infertility. Laparoscopy and ultrasonography showed obstruction of the right tube and ovulation from the right ovary only. Human menopausal gonadotrophin (hMG) therapy was used for six subsequent cycles, but did not result in conception. Subsequently, marked elevation of follicle-stimulating hormone (FSH) and testosterone, together with polycystic ovary (PCO) were noted. The patient failed to respond to ovarian stimulation by hMG. Severe ovarian dysfunction such as premature ovarian failure (POF) was strongly suspected. Sequence analysis of the LH beta-subunit gene indicated heterozygosity for point mutations Trp(8) to Arg(8) and Ile(15) to Thr(15) in the coding sequence. LH hypersecretion resembling that seen in PCO syndrome was observed. Induction of ovulation by hMG was successful in the first cycle in which the basal LH and FSH were well controlled with gonadotrophin-releasing hormone analog following estrogen-progesterone replacement. She conceived and delivered a healthy male infant at term. CONCLUSION: Clinicians should be clinically aware of patients with immunologically anomalous LH variant who might be at risk of developing ovarian failure within a relatively short time span. Pertinent treatment should be applied without delay in such cases. 相似文献
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Scale Arrangement Pattern in a Lepidopteran Wing. 1. Periodic Cellular Pattern in the Pupal Wing of Pieris rapae 总被引:1,自引:1,他引:0
In most species of lepidopteran insects, anteroposterior rows formed by scales are arranged at regular intervals in the adult wing; within each row two kinds of scales are alternately arranged. To investigate the cellular basis for the scale arrangement pattern, we examined cell arrangement in the epidermal monolayer of the pupal wing of a small white cabbage butterfly, Pieris rapae , by scanning electron microscopy and light microscopy.
The arrangement of scale precursor cells, closely resembling that of scales in the adult wing, was observed in the wing epidermis of the early pupa. Scale precursor cells are proximodistally elongated and form anteroposterior rows. Within a row two kinds of scale precursor cells are nearly alternately arranged, which is not so precise as the alternation of scales in the adult wing. Individual rows of scale precursor cells are separated by rows of single or double undifferentiated general epidermal cells. Occasionally, arrangement abnormalities occur both in the adult and the pupal wing. The cellular basis for the regular spacing of scale rows is discussed. 相似文献
The arrangement of scale precursor cells, closely resembling that of scales in the adult wing, was observed in the wing epidermis of the early pupa. Scale precursor cells are proximodistally elongated and form anteroposterior rows. Within a row two kinds of scale precursor cells are nearly alternately arranged, which is not so precise as the alternation of scales in the adult wing. Individual rows of scale precursor cells are separated by rows of single or double undifferentiated general epidermal cells. Occasionally, arrangement abnormalities occur both in the adult and the pupal wing. The cellular basis for the regular spacing of scale rows is discussed. 相似文献
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F Suzuki S Miyazaki M Uozumi N Okamoto S Yamashita K Murakami Y Nakamura 《FEBS letters》1989,256(1-2):47-50
The release of prorenin as well as renin from rat renal slices was confirmed by a rat prorenin-prosegment ELISA system and an assay system for determining the renin activity. A significant increase of the prorenin release was found by adding rat submandibular gland extract to the slice medium, indicating the existence of a prorenin-releasing stimulator (PRS) in the extract. The pI and molecular mass of PRS were 8.5-8.7 and 28-30 kDa, respectively. The PRS was completely inactivated by boiling or a proteinase treatment. 相似文献
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