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101.
Mayu Isotani Osamu Yamada Joshua L. Lachowicz Kyoichi Tamura Hiroko Yagihara Yasuhito Fujino Kenichiro Ono Tsukimi Washizu Makoto Bonkobara 《British journal of haematology》2010,148(1):144-153
The purpose of the current study was to investigate the mutation status of KIT in feline mast cell tumours (MCTs) and to examine the effects of tyrosine kinase inhibition on the phosphorylation of mutant kit in vitro and in clinical cases of cats. Sequence analysis of KIT identified mutations in 42/62 MCTs (67·7%). The vast majority of the mutations were distributed in exons 8 and 9, both of which encode the fifth immunoglobulin-like domain (IgD) of kit. All five types of kit with a mutation in the fifth IgD were then expressed in 293 cells and examined for phosphorylation status. The mutant kit proteins showed ligand-independent phosphorylation. The tyrosine kinase inhibitor imatinib mesylate suppressed the phosphorylation of these mutant kit proteins in transfectant cells. In a clinical study of 10 cats with MCTs, beneficial response to imatinib mesylate was observed in 7/8 cats that had a mutation in the fifth IgD of kit in tumour cells. Mutations in the fifth IgD of kit thus appear to be common and potentially sensitive to imatinib mesylate in feline MCTs. These data provide an in vivo model for paediatric mastocytosis where mutations in the fifth IgD of kit also occur. 相似文献
102.
Yoshihiko Shimizu Hiroko Yomo Nobuyuki Kita Kentaro Takahashi 《Archives of gynecology and obstetrics》2009,280(1):145-147
We report a patient with diffuse uterine leiomyomatosis, who wished to become pregnant. We performed hysteroscopic myomectomy
after treatment with nafarelin acetate for 6 months. The patient conceived spontaneously soon after hysteroscopic myomectomy,
and delivered a 2,798-g healthy baby. 相似文献
103.
In purpose of identifying thyroid tissue in patients with congenital hypothyroidism during childhood, ultrasonography is usually used as a screening examination, and scintigraphy is performed secondarily. Though these methods are useful, it is not easy to identify the accurate location of thyroid tissue by these methods. We previously reported the utility of computed tomography (CT) in identifying thyroid tissue in four cases of congenital hypothyroidism. The purpose of this study is to investigate whether CT is useful in identifying thyroid tissue, compared to ultrasonography or scintigraphy. Nineteen cases (0 month to 18 years of age) that were suspected to have ectopic thyroid tissue or thyroid agenesis on ultrasonography were examined by CT. CT was useful in diagnosing ectopic thyroid tissue or thyroid agenesis in all the cases, whereas ultrasonography or scintigraphy was less accurate in this purpose in seven cases. Plain CT had a difficulty in identifying thyroid tissue in two cases, in which contrasted image was required. This study showed that CT, especially an enhanced CT, is useful in identifying thyroid tissue, when the gland is not identified in the normal position by ultrasonography. 相似文献
104.
Extremely early onset of ranitidine action on human histamine H2 receptors expressed in HEK293 cells
Fukushima Y Ishikawa T Saitoh T Tateishi K Ogihara T Fujishiro M Shojima N Honda M Kushiyama A Anai M Sakoda H Ono H Onishi Y Otsuka H Katagiri H Nagai R Omata M Asano T 《Digestion》2003,68(2-3):145-152
BACKGROUND/AIMS: Histamine H2 receptor antagonists are considered to exert their effects on gastric acid secretion more rapidly than proton pump antagonists. However, there are no reports concerning the direct interaction of a histamine H2 receptor antagonist with the human H2 receptor in terms of onset of action. This study aims to characterize how rapidly famotidine and ranitidine, the most widely used histamine H2 receptor antagonists, interact with the human histamine H2 receptor. METHODS: HEK293 cell lines, stably expressing human histamine H2 receptors, were obtained. The dose- and time-dependent effects of famotidine and ranitidine on [3H]-tiotidine binding and histamine-stimulated cAMP production were analyzed. RESULTS: Ranitidine inhibited both [3H]-tiotidine binding and histamine-stimulated cAMP production more promptly than did famotidine. Inhibition of histamine-stimulated cAMP production by Cmax doses of famotidine (20 mg p.o.) and ranitidine (150 mg p.o.) peaked by 15 and 2 min, respectively. [3H]-tiotidine binding was not saturated by 60 min at the famotidine Cmax, while the ranitidine Cmax had produced saturation by 15 min. CONCLUSION: Ranitidine inhibits the human histamine H2 receptor very rapidly. 相似文献
105.
Pseudohypoparathyroidism type Ia (PHP-Ia), one of 4 types of PHP, is a genetic disease characterized by clinical hypoparathyroidism caused by parathyroid hormone (PTH) resistance. In addition, patients with PHP-Ia show resistance to other hormones as well as Albright's hereditary osteodystrophy (AHO), a constellation of features including short stature, obesity, brachydactyly, ectopic ossifications, and/or mental retardation. Hypocalcemia is one of the hallmarks of PHP-Ia, but several PHP-Ia patients have been described to have normocalcemia. We encountered a 10-year-old girl with typical Albright's hereditary osteodystrophy with round face, short stature, brachydactyly, and obesity. Biochemical examination showed normocalcemia and increased PTH levels. Ellsworth-Howard test did not show any responses of urinary cAMP and phosphate. Based on these findings, she was diagnosed as having PHP-Ia with normocalcemia. Sequencing analysis of the GNAS gene identified a heterozygous missense mutation in exon 13 (R385H), which was previously reported in a PHP-Ia patient. The exact reason for her normocalcemia is not determined, but we must recognize heterogeneous biochemical findings even in PHP-Ia. 相似文献
106.
107.
Nuamah MA Sagawa N Yura S Mise H Itoh H Ogawa Y Nakao K Fujii S 《Endocrine journal》2003,50(4):421-428
To clarify the mechanism of leptin resistance during pregnancy, we measured plasma leptin concentrations, free to total leptin ratio (percent free leptin) and soluble leptin receptor concentrations in pregnant women, and compared the results with those in non-pregnant women. We collected plasma samples from 23 non-pregnant and 31 pregnant women in the third trimester. Plasma samples from 5 pregnant women were collected longitudinally in each trimester. Plasma leptin concentrations in pregnant women in the second trimester (17.4 +/- 3.2 ng/ml) were higher than those in the first trimester of pregnancy (11.0 +/- 2.8 ng/ml, n = 5), as previously reported. However, percent free leptin did not change significantly throughout pregnancy. Percent free leptin correlated with total leptin concentrations (ng/ml) in non-pregnant women (r = 0.727, P < 0.0001), but not in women in the third trimester of pregnancy (r = 0.006). Constant percent free leptin during pregnancy despite increased leptin concentrations indicates increased leptin binding capacity in pregnant women, that might partly contribute to the establishment of leptin resistance. On the other hand, soluble leptin receptor concentrations showed significant negative correlation with BMI and plasma leptin concentrations in pregnant women (r = -0.470, P < 0.01 and r = -0.493, P < 0.01, respectively) but not in non-pregnant women. These data suggest the possibility that soluble leptin receptor is a minor component of leptin binding capacity in the plasma of pregnant women. 相似文献
108.
Tomoyuki Asano Yuzuka Saito Naoki Matsuoka Jumpei Temmoku Yuya Fujita Kasumi Hattori Shunsuke Kobayashi Akira Ojima Toshiyuki Takahashi Haruki Matsumoto Makiko Yashiro-Furuya Shuzo Sato Hiroko Kobayashi Hiroshi Watanabe Kiori Yano Tomomi Sasajima Kazuo Fujihara Kiyoshi Migita 《Medicine》2021,100(15)
Rationale:Anti-myelin oligodendrocyte protein antibody-associated disease (MOGAD) is a new disease entity with various clinical phenotypes. MOGAD often present with recurrent optic neuritis (ON), and it can also develop as a compartment of neuromyelitis optica spectrum disorder (NMOSD). Moreover, multiple autoantibodies such as an anti-myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) had been reported in the serum of patients with NMOSD.Patient concerns:We report an 86-year-old woman with a 2-year history of microscopic polyangiitis (MPA). The patient had a rapid loss of vision in her left eye. No abnormal findings were observed on her left fundus, and she tested negative for MPO-ANCA upon admission. However, anti-MOG antibodies were observed in the patient''s serum and cerebrospinal fluid.Diagnosis:A diagnosis of MOGAD complicated with MPA was made.Interventions:The patient received twice steroid pulse therapy and oral azathioprine as maintenance therapy.Outcomes:Her vision rapidly recovered, and no subsequent relapse was observed during the 8-month observation period.Conclusion:To the best of our knowledge, this is the first case of MOGAD complicated with MPA, and steroid pulse therapy and azathioprine therapy were effective for ON caused by MOGAD. 相似文献
109.
Yano H Suetake M Endo H Takayanagi R Numata M Ohyama K Sagai S Okitsu N Okamoto M Nishimura H Kobayashi T 《The Journal of infection》2005,51(4):e237-e240
Measles virus was isolated from the middle ear fluid (MEF) of two infant cases of acute otitis media (AOM) associated with measles. This is the first report on the isolation of measles virus from the MEF in patients with AOM, and possibility of the measles virus as a causative agent of AOM was suggested. 相似文献
110.
IGF-I stimulates both proliferation and differentiation of adipocyte-precursor cells, preadipocytes in vivo and in vitro. We have previously shown that IGF-I stimulates proliferation of 3T3-L1 preadipocytes through activation of MAPK and MAPK activation by IGF-I is mediated through the Src family of nonreceptor tyrosine kinases. In addition, we have shown that when 3T3-L1 cells reach growth arrest and are stimulated to differentiate, IGF-I can no longer activate the MAPK pathway. We hypothesized that the loss of IGF-I signaling to MAPK in differentiating 3T3-L1 cells is due to loss of IGF-I activation of Src family kinases. We measured c-Src kinase activity in cell lysates from proliferating, growth-arrested and differentiating 3T3-L1 cells. Src activity increased 2- to 4-fold in IGF-I-stimulated proliferating cells; however, IGF-I had a marginal affect on Src activity in growth-arrested cells and inhibited Src activity localized at the membrane in differentiating cells. C-terminal Src kinase (CSK), a ubiquitously expressed nonreceptor tyrosine kinase, negatively regulates the Src family kinases by phosphorylation of the Src C-terminal tyrosine. IGF-I decreased phosphorylation of the Src C-terminal tyrosine in proliferating cells and increased phosphorylation of this site in differentiating cells. IGF-I stimulated CSK kinase activity 2-fold in differentiating 3T3-L1 cells. An association between CSK and c-Src was detected by immunoprecipitation following IGF-I stimulation of differentiating but not proliferating 3T3-L1 cells. These results suggest that the loss of IGF-I downstream mitogenic signaling in differentiating 3T3-L1 cells is due to a change in IGF-I activation of c-Src and CSK may mediate the inactivation of c-Src by IGF-I in 3T3-L1 adipogenesis. 相似文献