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21.
Nishimura H Tokuyama K Arakawa H Ohki Y Sato A Kato M Mochizuki H Morikawa A 《International archives of allergy and immunology》2002,129(4):320-326
BACKGROUND: Chronic exposure to fenoterol (FEN), a beta(2)-adrenergic receptor (beta(2)-AR) agonist, was shown to induce both airway hyperresponsiveness and airway remodeling in experimental animals. OBJECTIVE: We wanted to know the effects of chronic exposure to procaterol (PRO), a beta(2)-AR agonist, on airway function and structure, because this agent is widely used as a bronchodilator in Japan. For comparison, the effects of FEN were also examined. METHODS: Aerosolized PRO (0.1 or 1 mg/ml), FEN (1 mg/ml) or vehicle (0.9% NaCl) was given to guinea pigs 3 times a day for 6 weeks. Sublaryngeal deposition of these agents was calculated using radioisotopes. At 72 h after the last inhalation of PRO, FEN or vehicle, the dose-response relationship between lung resistance (R(L)) and intravenously administered acetylcholine (ACh) was measured. After measuring R(L), histological changes in noncartilaginous airway dimensions were evaluated. RESULTS: The amount of sublaryngeal deposition of 0.1 mg/ml PRO in the present study was speculated to be 100 times larger than that of therapeutic dose. ACh concentrations causing 2-fold, 10-fold and maximal increases in R(L) were not different in 4 groups tested. In the smaller membranous airways (<0.4 mm in diameter), but not the larger ones, thickening of adventitial areas was significantly greater in animals treated with beta(2)-AR agonists than in control animals (23 and 25, and 96% higher in animals treated with 0.1 and 1 mg/ml PRO or 1 mg/ml FEN, respectively). The degree of the increase was significantly less in PRO-treated animals than in FEN-treated animals (p < 0.01). CONCLUSION: Our results did not provide any evidence that regular inhalation of PRO at the therapeutic dose might induce bronchial hyperresponsiveness. In addition, huge amounts of PRO only caused a mild thickening of the adventitial areas, suggesting that PRO may be a weak inducer of airway remodeling compared with FEN. 相似文献
22.
Tatsuo Yamazaki Shigeki Tomita Kazuhito Ichikawa Yuko Ono Fujiyuki Inaba Ichio Fukasawa Yasuo Imai Johji Imura Hirokazu Fukui Takahiro Fujimori Noriyuki Inaba 《Pathobiology》2006,73(4):176-182
OBJECTIVES: We investigated the relationship between P16-immunostaining patterns and clinicopathological factors in early uterine cervix cancers and assessed whether P16-immunostaining patterns predict the prognosis of the patients with early uterine cervix cancers. METHODS: Twenty-nine early squamous cell carcinoma (SCC) specimens of the uterus were examined using immunohistochemistry for P16 expression. The P16-immunostaining pattern was classified into two groups: the homogeneous type and the heterogeneous type. P16-immunostaining patterns were evaluated in different parts of the carcinoma in situ (CIS): the center of the tumor and the front interface of the infiltrating tumor. RESULTS: All specimens were of the homogeneous type in CIS. The P16-immunostaining pattern was significantly of the heterogeneous type in the front interface of the infiltrating tumor with lymphatic invasion, vascular invasion, lymph node metastasis, and recurrence. Regarding the P16-immunostaining patterns in the front interface of the infiltrating tumor, the patients with the heterogeneous type showed a significantly worse prognosis than the patients with the homogeneous type. CONCLUSIONS: The prognosis of patients with early uterine cervical SCC may be predicted by evaluating the P16-immunostaining pattern in the front interface of the infiltrating tumor. 相似文献
23.
Makoto Fujimura Takashi Kamakura Hirokazu Inoue Isamu Yamaguchi 《Current genetics》1994,25(5):418-422
We have previously shown that increased sensitivity to diethofencarb in the carbendazim(MBC)-resistant F914 strain of Neurospora crassa is caused by a single amino-acid change in -tubulin, 198Glu to Gly. Three diethofencarb-resistant mutants that are also resistant to MBC were isolated from strain F914. They contained single base-pair-substitution mutations in the -tubulin gene. The amino acid changes in -tubulin, Phe from 250Leu, Val from 165Ala, and Ala from 237Thr, were responsible for diethofencarb-resistance in the mutant strains FR511, FR513, and FR421, respectively. The amino acid at position 198 of -tubulin in these mutants was Gly, which is the same as in strain F914. -tubulin genes with 198Glu were constructed by site-directed mutagenesis. The altered -tubulin genes derived from FR511 and FR421 transformed the wild-type strain to resistance to MBC, indicating that 250Phe and 237Ala in -tubulin are responsible for resistance not only to diethofencarb but also to MBC. 相似文献
24.
25.
Okamoto T Hashimoto M Samejima H Mori A Wakabayashi M Takeda A Nakamura H Naruse H Bouike Y Araki N 《Immunopharmacology and immunotoxicology》2004,26(4):645-652
Immediate hemolytic transfusion reactions (IHTR) occurred in the course of delayed hemolytic transfusion reactions (DHTR). An 84-year-old man had received a blood transfusion 20 years ago. Progressive anemia developed, because of continuous bleeding from a bladder tumor. He was transfused with concentrated red blood cells (CRC) which were Rh-E antigen negative, because he had anti-E antibodies (day 0). He received CRC on day 3, and underwent resection of bladder tumor on day 6. Although crossmatch-compatible CRCs were prepared for the operation, those were not required and were kept in a refrigerator in the ward. On day 9, when a CRC kept in the ward was transfused, he suddenly had a IHTR. In order to analyze a mechanism of IHTR, the anti-Jk(b) and anti-Di(b) antibodies, anti-HLA antibodies and the concentrations of inflammatory cytokines were measured in serum samples. The anti-Jk(b) and anti-Di(b) antibodies increased prior to IHTR experienced on day 9. The concentrations of IL-6 and IL-1beta increased from day 2, while the concentration of IL-8 increased from day 7. The anti-HLA class I antibody could be detected 2 days before IHTR. Thus, the anti-Jk(b) and anti-Di(b) antibodies induced the production of inflammatory cytokines and symptoms of DHTR and IHTR. The anti-HLA class I antibody could be produced in spite of using the filer for removing leukocytes, and may take part in the induction of IHTR. Further, blood products should be transfused soon after completing a crossmatch test in patients with anti-RBC alloantibodies. 相似文献
26.
Role of apoptosis controlled by cytochrome c released from mitochondria for luteal function in human granulosa cells 总被引:1,自引:0,他引:1
Makino A Ozaki Y Matsubara H Sato T Ikuta K Nishizawa Y Suzumori K 《American journal of reproductive immunology (New York, N.Y. : 1989)》2005,53(3):144-152
PROBLEM: The aim of this study was to investigate the relationship between apoptosis by the mitochondrial pathway and luteal function in human granulosa cells. METHOD OF STUDY: Granulosa cells were obtained by ultrasound-guided follicular aspiration from patients undergoing in vitro fertilization and embryo transfer. After the addition of RU486, cells were stained with a mitochondria-specific fluorescent dye, MitoTracker Red CM x Ros. Using flow cytometry and National Institute of Health image, the mitochondrial fluorescent area was measured. After staining with Hoechst 33258 dye, the number of apoptotic bodies per 1000 cells were counted at random on photomicrographs. Homogenates were used for sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blot analysis using antibodies against cytochrome c or caspase-3. RESULTS: The incidence of apoptotic bodies increased and the mitochondrial membrane potential decreased time dependently. The opposite effect was observed dose dependently with RU486 treatment. Western blot analysis showed increased cytochrome c expression, after treatment with 1-2 microg/mL of RU486 which then decreased with 5-10 microg/mL of RU486. Caspase-3 expression increased dose dependently with RU486. CONCLUSIONS: These results suggest that the activation of caspase-3 caused by cytochrome c released from mitochondria plays an important role in apoptosis-related luteal function in human granulosa cells. 相似文献
27.
A case of the clear cell variant of hepatocellular carcinoma with an abundant myxoid stroma is presented. The tumor occurred in a 55-year-old Japanese man, and swelling of the scrotum was the initial symptom. The patient underwent high-level orchiectomy, and the pathologic diagnosis was a metastatic tumor on the surface of the processus vaginalis and intact testis. Extensive examination failed to show a primary site. Subsequent autopsy revealed a large hepatic tumor and metastatic nodules with a prominent myxoid appearance in multiple organs. Histologically, each tumor consisted of uniform small tumor cells with clear cytoplasm attributed to abundant accumulation of glycogen particles, and an abundant myxoid stroma was also present. The tumor cells were positive for keratin, alpha 1-antitrypsin, alpha 1-antichymotrypsin, liver ferritin, prealbumin, and fibrinogen, but lacked alpha-fetoprotein. These findings indicated that this case was hepatocellular carcinoma of the clear cell type with a prominent myxoid stroma. 相似文献
28.
Fujiwara K Maruyama M Usui K Sakai T Matsumoto H Hinuma S Kitada C Inoue K 《Neuroscience letters》2003,338(2):127-130
Prolactin-releasing peptide (PrRP) was found to be a novel hypothalamic peptide that stimulates prolactin release in vitro and in vivo. In the normal adult rat brain, PrRP neurons are known to be located in only three areas, i.e. the dorsomedial hypothalamic nucleus, ventrolateral reticular formation; and nucleus of the tractus solitarius in the medulla oblongata. These PrRP neurons project neurites into various brain areas, including regions such as the paraventricular nucleus, supraoptic nucleus, and bed nucleus of the stria terminalis. Both PrRP nerve fibers and a high level of PrRP receptor, UHR-1, mRNA are observed in the area postrema (AP),but no PrRP neurons are detected in the AP of normal rats. In this study, we clearly demonstrated that PrRP-producing cells newly appeared in the AP of adrenalectomized rats by in situ hybridization and immunocytochemistry. Our results suggest that PrRP may have some important roles in the AP of adrenalectomized rats. This is the first report demonstrating the appearance of PrRP-positive cells in the AP. 相似文献
29.
Jo EK Kumaki S Wei D Tsuchiya S Kanegane H Song CH Noh HY Kim YO Kim SY Chung HY Kim YH Kook H 《Journal of Korean medical science》2004,19(1):123-126
X-linked severe combined immunodeficiency (X-SCID) is a rare, life-threatening immune disorder, caused by mutations in the gamma c chain gene, which encodes an essential component of the cytokine receptors for interleukin-2 (IL-2), IL-4, IL-7, IL-9, IL-15, and IL-21. A 13-month-old boy with recurrent infections who had reduced serum immunoglobulin levels and decreased numbers of CD3, CD16/56 cells was evaluated for gamma c chain gene mutation and protein expression. The patient had a C-to-T point mutation at nucleotide position 690, one of the hot spots, resulting in a single amino acid substitution of cysteine for arginine (R226C), as determined by direct sequencing and PCR-RFLP. The patient's mother was a heterozygous carrier. Percutaneous umbilical cord blood sampling was performed at the 6-month of gestation in a subsequent pregnancy. As the immunophenotype of the fetus showed an identical pattern, the pregnancy was terminated and genetic analysis of the abortus confirmed recurrence. This is the first report of the molecular diagnosis of X-SCID in Korea. Genetic analysis of the gamma c chain gene is useful for definite diagnosis and genetic counseling for X-SCID. 相似文献
30.
T Fukuda Y Ohnishi K Sato S Tachikawa T Tamura T Uehara I Emura 《Acta pathologica japonica》1991,41(2):143-149
We report six cases of carcinoma showing sarcomatous change in the urinary tract examined by conventional histochemistry and immunohistochemistry. All of the cases were transitional cell carcinoma with or without focal squamous cell carcinoma. Sarcomatous components resembling spindle cell sarcoma with a marked myxoid stroma or chondrosarcomatous element were also observed in all cases. The sarcomatous elements were closely associated with the areas of squamous cell carcinoma in three cases. Various histochemical staining procedures demonstrated mesenchymal features in the stroma of sarcomatous areas. By immunohistochemical examination, the epithelial components showed positive reactions for keratin, epithelial membrane antigen and, focally, carcinoembryonic antigen. The sarcomatous components revealed a positive immunoreaction for keratin but lacked other epithelial markers in all cases. Chondrosarcomatous elements in two cases were positive for both keratin and S-100 protein. These findings indicate that sarcomatous elements in carcinoma may represent mesenchymal metaplasia with partial or complete loss of epithelial features. However, further study will be necessary in order to determine whether heterogeneous elements, such as chondrosarcomatous areas, are epithelial or truly mesenchymal in origin. 相似文献