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81.
Yoshioka S Fujiwara H Higuchi T Yamada S Maeda M Fujii S 《Molecular human reproduction》2003,9(6):311-319
Melanoma cell adhesion molecule (MCAM) was originally reported to be involved in the invasion and progression of melanoma. It was also shown to be responsible for the attachment of cells to endothelial cells. In this study, we demonstrated by immunohistochemistry that immunoreactive MCAM was not expressed on granulosa cells in the pre-ovulatory follicle, but it was clearly detected in large luteal cells in corpora lutea from the mid-luteal phase of the menstrual cycle. Northern blotting analysis confirmed the expression of MCAM mRNA in corpus luteum. MCAM was weakly detected by immunocytochemical staining in human luteinizing granulosa cells isolated from patients undergoing IVF treatment. Its expression was found to be increased during time in culture of these cells. Flow cytometry and Northern blot analysis revealed that MCAM expression on luteinizing granulosa cells was enhanced when the cells were cultured for 5 days in the presence of hCG (1 IU/ml) or cytokines such as interleukin-1alpha (10 ng/ml) and tumour necrosis factor-alpha (10 ng/ml). No significant difference of MCAM expression was observed between the cultures under normoxic (20% oxygen) and hypoxic (1% oxygen) conditions. These results indicate that luteinizing granulosa cells express MCAM and that MCAM expression is regulated by LH/hCG and cytokines during luteinization. Since MCAM has been reported to mediate cellular interaction with endothelial cells, this molecule may play a role in neovascularization during corpus luteum formation in the human ovary. 相似文献
82.
Komei Ito Masaki Futamura Yuri Takaoka Masashi Morishita Kumiko Nakanishi Tatsuo Sakamoto 《Arerugī》2008,57(8):1043-1052
Background: A method for open food challenge test to determine food allergy has not been established in an evidence-based manner. Methods: We conducted an analysis of 438 open food challenges of raw milk (n=133, mean age 2.7+/-1.9 years), boiled egg white (n=216, 2.8+/-2.1 years) or udon noodles (n=89, 2.7+/-1.7 years) for the patients aged 1 year or more. Doses were increased (trace amounts, 1 g, 2 g, 5 g, 10 g, 20-30 g) every 20 minutes. Results: In total, 151 (38.5%) of food challenges were positive. The positive rates of milk, egg and wheat challenges were 35.8%, 42.4% and 33.3%, respectively. Of these, 76.2%, 32.5%, 27.8% and 0.7% had, respectively, skin, respiratory, gastrointestinal and cardiovascular symptoms. Although the prevalence of positive challenge increased with level of specific IgE, it did not correlate with the threshold amount of positive food challenge or the severity of symptoms. Among the challnege positive patients, 10.6% required injection of antihistamines, corticosteroids or adrenalines for the treatment of the symptoms. Conclusions: This challenge protocol seemed to be appropriate and safe. 相似文献
83.
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85.
Yoshino H Futakuchi M Cho YM Ogawa K Takeshita F Imai N Tamano S Shirai T 《Clinical & experimental metastasis》2005,22(5):441-447
Previously, we established the in vivo lung metastasis model of rat HCC induced by two hepatocarcinogens, diethylnitrosamine (DEN) and N-nitrosomorpholine (NMOR)
at a dose of 120 ppm. This model allows us to investigate modifying factors leading to the inhibition of metastasis formation.
However, low survival rates made the evaluation of metastasis formation difficult. The current experiments were conducted
to modify the experimental protocol to improve survival and to establish a better animal metastasis model. Lower doses of
NMOR (80 or 40 ppm in drinking water) were given to F344 rats for 14 weeks after DEN treatment. Survival rates in the 80 ppm
group and in the 40 ppm group were 57% and 81%, respectively and these values were significantly higher than that in 120 ppm.
Incidences of lung metastasis in the 40 ppm group steadily increased up to 67% by week 36 while that in the 80 ppm increased
sharply up to 86% by week 24. Severity of lung metastases in the 40 ppm group at week 36 was mild compared with the 80 ppm
group at week 24. In the second experiment, in order to characterize HCC development and lung metastasis in the 40 ppm group,
rats given DEN and then followed with 40 ppm NMOR were killed sequentially. Development of HCC was observed at week 14 and
reached 100% incidence at week 20. First lung metastatic lesions were evident at week 22, and incidence of lung metastasis
reached 100%. Tumor cells were identified in the blood at week 20 by RT-PCR. The current study revealed that 40 ppm NMOR for
14 weeks after DEN treatment developed HCC without lung metastases at week 22, then HCC with a frequent lung metastasis at
week 40. Thus, it can be said that this system is a more appropriate model for elucidation of mechanisms of metastasis and
also for analysis of factors to inhibit natural metastasis. 相似文献
86.
Lamont RE Loredo-Osti J Roslin NM Mauthe J Coghlan G Nylen E Frappier D Innes AM Lemire EG Lowry RB Greenberg CR Triggs-Raine BL Morgan K Wrogemann K Fujiwara TM Zelinski T 《American journal of medical genetics. Part A》2005,(2):136-143
Bowen-Conradi syndrome (BCS) is a lethal autosomal recessive disorder with an estimated incidence of 1 in 355 live births in the Hutterite population. A few cases have been reported in other populations. Here, we report the results of a genome-wide scan and fine mapping of the BCS locus in Hutterite families. By linkage and haplotype analysis the BCS locus was mapped to a 3.5 cM segment (1.9 Mbp) in chromosome region 12p13.3 bounded by F8VWF and D12S397. When genealogical relationships among the families were taken into account in the linkage analysis, the evidence for linkage was stronger and the number of potentially linked regions was reduced to one. Under the assumption that all the Hutterite patients were identical by descent for a disease-causing mutation, haplotype analysis was used to infer likely historical recombinants and thereby narrow the candidate region to a chromosomal segment shared in common by all the affected children. This study also demonstrates that BCS and cerebro-oculo-facial-skeletal syndrome (COFS) are genetically distinct. 相似文献
87.
Matsuda J Kido M Tadano-Aritomi K Ishizuka I Tominaga K Toida K Takeda E Suzuki K Kuroda Y 《Human molecular genetics》2004,13(21):2709-2723
The sphingolipid activator proteins (saposins A, B, C and D) are small homologous glycoproteins that are encoded by a single gene in tandem within a large precursor protein (prosaposin) and are required for in vivo degradation of some sphingolipids with relatively short carbohydrate chains. Human patients with prosaposin or specific saposin B or C deficiency are known, and prosaposin- and saposin A-deficient mouse lines have been generated. Experimental evidence suggests that saposin D may be a lysosomal acid ceramidase activator. However, no specific saposin D deficiency state is known in any mammalian species. We have generated a specific saposin D(-/-) mouse by introducing a mutation (C509S) into the saposin D domain of the mouse prosaposin gene. Saposin D(-/-) mice developed progressive polyuria at around 2 months and ataxia at around 4 months. Pathologically, the kidney of saposin D(-/-) mice showed renal tubular degeneration and eventual hydronephrosis. In the nervous system, progressive and selective loss of the cerebellar Purkinje cells in a striped pattern was conspicuous, and almost all Purkinje cells disappeared by 12 months. Biochemically, ceramides, particularly those containing hydroxy fatty acids accumulated in the kidney and the brain, most prominently in the cerebellum. These results not only indicate the role of saposin D in in vivo ceramide metabolism, but also suggest possible cytotoxicity of ceramide underlying the cerebellar Purkinje cell and renal tubular cell degeneration. 相似文献
88.
Myopathy phenotype in transgenic mice expressing mutated PABPN1 as a model of oculopharyngeal muscular dystrophy 总被引:1,自引:2,他引:1
Hino H Araki K Uyama E Takeya M Araki M Yoshinobu K Miike K Kawazoe Y Maeda Y Uchino M Yamamura K 《Human molecular genetics》2004,13(2):181-190
Autosomal dominant oculopharyngeal muscular dystrophy (OPMD)is a late-onset disorder characterized clinically by progressiveptosis, dysphagia and limb weakness, and by unique intranuclearinclusions in the skeletal muscle fibers. The disease is causedby the expansion of a 10-alanine stretch to 1217 alanineresidues in the poly(A)-binding protein, nuclear 1 (PABPN1;PABP2). While PABPN1 is a major component of the inclusionsin OPMD, the exact cause of the disease is unknown. To elucidatethe molecular mechanism and to construct a useful model fortherapeutic trials, we have generated transgenic mice expressingthe hPABPN1. Transgenic mice lines expressing a normal hPABPN1with 10-alanine stretch did not reveal myopathic changes, whereaslines expressing high levels of expanded hPABPN1 with a 13-alaninestretch showed an apparent myopathy phenotype, especially inold age. Pathological studies in the latter mice disclosed intranuclearinclusions consisting of aggregated mutant hPABPN1 product.Furthermore, some TUNEL positive nuclei were shown around degeneratingfibers and a cluster of it in the lesion in necrotic musclefibers. Interestingly, the degree of myopathic changes was moreprominent in the eyelid and pharyngeal muscles. Further, muscleweakness in the limbs was apparent as shown by the fatigabilitytest. Nuclear inclusions seemed to develop gradually with aging,at least after 1 week of age, in model mouse muscles. We establishedthe first transgenic mouse model of OPMD by expressing mutatedPABPN1, and our model mice appear to have more dramatic alternationsin myofiber viability. * To whom correspondence should be addressed. Tel: +81 963736083; Fax: +81 963736599; Email: yamamura{at}gpo.kumamoto-u.ac.jp 相似文献
89.
Kitada S Maekura R Toyoshima N Naka T Fujiwara N Kobayashi M Yano I Ito M Kobayashi K 《Clinical and diagnostic laboratory immunology》2005,12(1):44-51
We report the development of a serodiagnostic method for Mycobacterium avium complex (MAC) disease with an enzyme immunoassay (EIA) with the MAC-specific glycopeptidolipid (GPL) core as the antigen. In this study, we confirmed by EIA that the GPL core antibody was in the sera of immunocompetent patients with MAC disease. The EIA for quantifying the GPL core antibody was evaluated as a clinical tool for serodiagnosis of pulmonary MAC disease. A significant increase in GPL core antibodies (immunoglobulins G, A, and M) was detected in sera of patients with MAC pulmonary diseases when they were compared to patients who were colonized with MAC, patients with Mycobacterium kansasii disease or tuberculosis, and healthy subjects. The sensitivities and specificities of the GPL core-based EIA for diagnosis of MAC pulmonary disease were 72.6% and 92.2%, respectively, for IgG, 92.5% and 95.1%, respectively, for IgA, and 78.3% and 91.0%, respectively, for IgM. The best sensitivity and specificity were obtained by measuring immunoglobulin A antibodies against GPL core antigen. The level of GPL core antibodies reflected disease activity, since it decreased in cured MAC patients who had responded to chemotherapy. Measurement of serum antibodies against GPL core is useful for both diagnosis and assessment of disease activity in MAC disease of the lung. 相似文献
90.
Summary After intranasal inoculation of suckling rats mouse hepatitis virus multiplied mostly in the nasal epithelium; though there were no symptoms, antibodies were produced. Antibodies were also demonstrated in adult rats. These findings suggest that the rat may be a natural host for the virus.With 2 Figures 相似文献