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991.
Yamagami K Yoshioka K Isaka Y Inoue T Hosoi M Shakudo M Iwai Y Sato T 《Endocrine journal》2008,55(2):339-344
An 18-year-old man with 4-year history of central diabetes insipidus and partial pituitary dysfunction was admitted to our hospital because of headache and nasal discharge. Magnetic resonance imaging (MRI) revealed abnormal mass in the sella turnica invading into the cavernous sinus and sinus maxillaries along with thickened tentorium cerebelli. Histopathology of the mass in the sinus maxillaries revealed spindle-shaped cells arranged in a fascicular pattern with varied myxoid and collagenized regions with various inflammatory cells. Immunostaining revealed the spindle-shaped cells were positive for smooth muscle actin. These features were identical to those of inflammatory myofibroblastic tumor (IMT). He was diagnosed with IMT in the sella turnica and other regions. Corticosteroid therapy improved clinical symptoms and follow-up MRI revealed amelioration of the thickened tentorium cerebelli. However, the other lesions were unchanged and pituitary dysfunction did not improve. Although rare, IMT should be considered in the differential diagnosis of a sellar mass. Early treatment with corticosteroid therapy may reduce the risk of disease progression. 相似文献
992.
Fukami M Horikawa R Nagai T Tanaka T Naiki Y Sato N Okuyama T Nakai H Soneda S Tachibana K Matsuo N Sato S Homma K Nishimura G Hasegawa T Ogata T 《The Journal of clinical endocrinology and metabolism》2005,90(1):414-426
We report on molecular and clinical findings in 10 Japanese patients (four males and six females) from eight families (two pairs of siblings and six isolated cases) with Antley-Bixler syndrome accompanied by abnormal genitalia and/or impaired steroidogenesis. Direct sequencing was performed for all the 15 exons of cytochrome P450 oxidoreductase gene (POR), showing two missense mutations (R457H and Y578C), a 24-bp deletion mutation resulting in loss of nine amino acids and creation of one amino acid (L612_W620delinsR), a single bp insertion mutation leading to frameshift (I444fsX449), and a silent mutation (G5G). R457H has previously been shown to be a pathologic mutation, and computerized modeling analyses indicated that the 15A>G for G5G could disturb an exonic splicing enhancer motif, and the remaining three mutations should affect protein conformations. Six patients were compound heterozygotes, and three patients were R457H homozygotes; no mutation was identified on one allele of the remaining one patient. Clinical findings included various degrees of skeletal features, such as brachycephaly, radiohumeral synostosis, and digital joint contractures in patients of both sexes, normal-to-poor masculinization during fetal and pubertal periods in male patients, virilization during fetal life and poor pubertal development without worsening of virilization in female patients, and relatively large height gain and delayed bone age from the pubertal period in patients of both sexes, together with maternal virilization during pregnancy. Blood cholesterol was grossly normal, and endocrine studies revealed defective CYP17A1 and CYP21A2 activities. The results suggest that Antley-Bixler syndrome with abnormal genitalia and/or impaired steroidogenesis is caused by POR mutations, and that clinical features are variable and primarily explained by impaired activities of POR-dependent CYP51A1, CYP17A1, CYP21A2, and CYP19A1. 相似文献
993.
Yokoyama M Nakahara K Kojima M Hosoda H Kangawa K Murakami N 《European journal of endocrinology / European Federation of Endocrine Societies》2005,152(1):155-160
OBJECTIVES: Ghrelin has recently been isolated from rat and human stomach as an endogenous ligand for the growth hormone (GH) secretagog receptor. Using beagle dogs, we investigated the distribution of ghrelin in the stomach and its possible role. METHODS: We examined: (i) GH release in response to ghrelin injection (0.5 or 5 microg/kg, i.v.), (ii) gastric localization of ghrelin-immunostained cells, (iii) changes in daily food consumption after ghrelin injection (3, 10, and 20 microg/kg, i.v.), (iv) plasma ghrelin levels under regular, but restricted feeding conditions, and (v) variations in plasma ghrelin levels in relatively lean, normal and obese dogs. RESULTS: Administration of ghrelin to dogs promptly increased circulating GH concentrations, although this effect was transitory and was maintained for only 20 min. Ghrelin was localized in the stomach fundus and body, but none was detected in either the pylorus or cardia. Administration of ghrelin at a dose of 20 microg/kg increased the daily food intake of beagle dogs. Plasma ghrelin levels peaked just before meal times, and then returned to basal levels. Obese dogs had higher plasma ghrelin levels than did normal and lean dogs. CONCLUSIONS: These results indicate that ghrelin is a potent GH secretagog in dogs. The distribution of ghrelin-immunoreactive cells in the canine stomach resembles that of both the murine and human stomach. Ghrelin participates in the control of feeding behavior and energy homeostasis in dogs and may, therefore, be involved in the development of obesity. 相似文献
994.
Tanaka D Isobe J Kimata K Shima T Watahiki M 《Kansenshōgaku zasshi. The Journal of the Japanese Association for Infectious Diseases》2005,79(7):443-450
Group A Streptococci (GAS) from patients with pharyngitis and skin infections were examined for T serotypes, emm types, and streptococcal pyrogenic exotoxin gene types. The results were summarized as follows: 1) T and emm types were determined in 130 GAS isolates obtained between 2000 and 2004. Among 85 throat isolates, predominant T/emm types were T12/emm12 (25%), T4/emm4 (19%), and T1/emm1 (14%). Among 45 skin isolates, predominant T/emm types were T28/emm28 (13%), TB 3264/emm89 (13%), Tnontypeable/emm58 (13%), T1/emm1 (11%), and T12/emm12 (11%). Predominant T/emm types of skin isolates in 2000-2004 slightly differed from those during 1990s in our previous report. 2) The presence of streptococcal pyrogenic exotoxin genes in 292 GAS isolates obtained between 1990 and 2004 was examined. Significantly lower proportion of skin isolates, compared with throat isolates, was found to harbor the speA gene (12 versus 26%, respectively; p<0.01), or the speC gene (40 versus 65%, respectively; P<0.01). All but one of tested isolates carried the speB gene. The speB-negative isolate was identified as S. dysgalactiae subsp. equisimilis with the group A antigen. 3) Types of the speA alleles were determined in 59 speA-positive GAS isolates. Among 44 throat isolates, 37 (84%) were speA lineage I (speA1-speA2-speA3-speA6), and 7 (16%) were lineage II (speA4-speA5). Among 15 skin isolates, 11 (73%) were lineage I and 4 (27%) were lineage II. The pairwise associations were observed between emm type and speA allele: emm1 and speA2, emm3 and speA3, emm6 and speA4, emm11 and speA2, emm18 and speA1. 相似文献
995.
After antithyroid drug (ATD) treatment for Graves' disease, either a relapse of Graves' thyrotoxicosis or painless thyroiditis can develop. It is important to differentiate these two types of thyrotoxicosis because of the difference in required therapy. However, differentiation of thyrotoxicosis is usually difficult without radioactive iodine uptake (RAIU) which is not available in general practice. We investigated the clinical usefulness of the 2nd generation assay for anti-TSH receptor antibodies (TRAb) to differentiate these two types of thyrotoxicosis after ATD treatment for Graves' disease. We recruited 26 patients who developed thyrotoxicosis after ATD treatment for Graves' disease. These patients once became negative for TRAb and seemed to be in remission after ATD treatment. Upon development of thyrotoxicosis after ATD treatment, TSH, free T4, free T3 and TRAb were measured. TRAb were measured by the 2nd generation assay using recombinant human TSH receptors instead of porcine TSH receptors. Fourteen patients relapsed into Graves' thyrotoxicosis and 12 patients developed painless thyroiditis. Twelve (85.7%) of 14 patients with relapse of Graves' thyrotoxicosis were positive for TRAb. Eleven (91.7%) of 12 patients with development of painless thyroiditis after ATD treatment for Graves' disease were negative for TRAb. Levels of TRAb were significantly different between patients with relapse of Graves' thyrotoxicosis (4.86 +/- 6.45 IU/L) and those with painless thyroiditis (0.62 +/- 0.61 IU/L) (P<0.001). The 2nd generation assay for TRAb was useful to differentiate relapse of Graves' thyrotoxicosis from development of painless thyroiditis in patients who seemed to be in remission after ATD treatment for Graves' disease. 相似文献
996.
997.
Sugimoto-Shirasu K Roberts GR Stacey NJ McCann MC Maxwell A Roberts K 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(51):18736-18741
How cells achieve their final sizes is a pervasive biological question. One strategy to increase cell size is for the cell to amplify its chromosomal DNA content through endoreduplication cycles. Although endoreduplication is widespread in eukaryotes, we know very little about its molecular mechanisms. Successful progression of the endoreduplication cycle in Arabidopsis requires a plant homologue of archaeal DNA topoisomerase (topo) VI. To further understand how DNA is endoreduplicated and how this process is regulated, we isolated a dwarf Arabidopsis mutant, hyp7 (hypocotyl 7), in which various large cell types that in the wild type normally endoreduplicate multiple times complete only the first two rounds of endoreduplication and stall at 8C. HYP7 encodes the RHL1 (ROOT HAIRLESS 1) protein, and sequence analysis reveals that RHL1 has similarity to the C-terminal domain of mammalian DNA topo IIalpha, another type II topo that shares little sequence homology with topo VI. RHL1 shows DNA binding activity in vitro, and we present both genetic and in vivo evidence that RHL1 forms a multiprotein complex with plant topo VI. We propose that RHL1 plays an essential role in the topo VI complex to modulate its function and that the two distantly related topos, topo II and topo VI, have evolved a common domain that extends their function. Our data suggest that plant topo II and topo VI play distinct but overlapping roles during the mitotic cell cycle and endoreduplication cycle. 相似文献
998.
Yoshitaka Seki Tatsuki Mizuochi Akihiko Kimura Tomoyuki Takahashi Akira Ohtake Shin-Ichi Hayashi Toshiya Morimura Yasuharu Ohno Takayuki Hoshina Kenji Ihara Hajime Takei Hiroshi Nittono Takao Kurosawa Keiko Homma Tomonobu Hasegawa Toyojiro Matsuishi 《Journal of inherited metabolic disease》2013,36(3):565-573
Background and aims
In two Japanese infants with neonatal cholestasis, 3-oxo-Δ4-steroid 5β-reductase deficiency was diagnosed based on mutations of the SRD5B1 gene. Unusual bile acids such as elevated 3-oxo-Δ4 bile acids were detected in their serum and urine by gas chromatography–mass spectrometry. We studied effects of oral chenodeoxycholic acid treatment.Patients and methods
SRD5B1 gene analysis used peripheral lymphocyte genomic DNA. Diagnosis and treatment of these two patients were investigated retrospectively and prospectively investigated.Results
With respect to SRD5B1, one patient was heterozygous (R266Q, a novel mutation) while the other was a compound heterozygote (G223E/R261C). Chenodeoxycholic acid treatment was effective in improving liver function and decreasing unusual bile acids such as 7α-hydroxy- and 7α,12α-dihydroxy-3-oxo-4-cholen-24-oic acids in serum and urine.Conclusion
Primary bile acid treatment using chenodeoxycholic acid was effective for these patients treated in early infancy before the late stage of chronic cholestatic liver dysfunction. 相似文献999.
Takeshi Kashimura Makoto Kodama Komei Tanaka Keiko Sonoda Satoru Watanabe Yukako Ohno Makoto Tomita Hiroaki Obata Wataru Mitsuma Masahiro Ito Satoru Hirono Haruo Hanawa Yoshifusa Aizawa 《Heart and vessels》2013,28(3):336-344
Mechanical alternans (MA) is frequently observed in patients with heart failure, and is a predictor of cardiac events. However, there have been controversies regarding the conditions and mechanisms of MA. To clarify heart rate-dependent contractile properties related to MA, we performed incremental right atrial pacing in 17 idiopathic dilated cardiomyopathy (DCM) patients and in six control patients. The maximal increase in left ventricular dP/dt during pacing-induced tachycardia was assessed as the force gain in the force–frequency relationship (FG-FFR), and the maximal increase in left ventricular dP/dt of the first post-pacing beats was examined as the force gain in poststimulation potentiation (FG-PSP). As a result, MA was induced in 9 DCM patients (DCM MA(+)) but not in the other 8 DCM patients (DCM MA(?)), and not in any of the control patients. DCM MA(+) had significantly lower FG-FFR (34.7 ± 40.9 vs 159.4 ± 103.9 mmHg/s, P = 0.0091) and higher FG-PSP (500.0 ± 96.8 vs 321.9 ± 94.9 mmHg/s, P = 0.0017), and accordingly a wider gap between FG-PSP and FG-FFR (465.3 ± 119.4 vs 162.5 ± 123.6 mmHg/s, P = 0.0001) than DCM MA(?) patients. These characteristics of DCM MA(+) showed clear contrasts to those of the control patients. In conclusion, MA is caused with an impaired force–frequency relationship despite significant poststimulation potentiation, suggesting that MA reflects ineffective utilization of the potentiated intrinsic force during tachycardia. 相似文献
1000.
Rintaro Mikata Takeshi Ishihara Motohisa Tada Katsunobu Tawada Masayoshi Saito Joe Kurosawa Harutoshi Sugiyama Yuji Sakai Toshio Tsuyuguchi Masaru Miyazaki Osamu Yokosuka 《Journal of gastroenterology》2013,48(7):866-873