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1.
Marie Ohata Susumu Fujiwara Ai Yoshioka Hiroshi Nagai Shintaro Sugita Nozomi Yamano Yusuke Inoue Chikako Nishigori 《Pediatric dermatology》2019,36(6):997-998
Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy. 相似文献
2.
3.
Shigeji Matsumoto Mizuho Ikeda Toshimi Nishikawa Shinki Yoshida Takeshi Tanimoto Masahiro Ito Chikako Saiki Mamoru Takeda 《The Journal of pharmacology and experimental therapeutics》2002,300(2):597-604
The excitatory responses of deflationary slowly adapting pulmonary stretch receptor (SAR) activity to lung deflation ranging from approximately -15 to -25 cm of H(2)O for approximately 5 s were examined before and after administration of flecainide, a Na(+) channel blocker, and K(+) channel blockers, such as 4-aminopyridine (4-AP) and tetraethylammonium (TEA). The experiments were performed in anesthetized, artificially ventilated rats after unilateral vagotomy. The deflationary SARs increased their activity during lung deflation and its effect became more pronounced by increasing the degree of negative pressure. During lung deflation the average values for the deflationary SAR adaptation index (AI) were below 40%. Intravenous administration of veratridine (50 microg/kg), an Na(+) channel opener, stimulated deflationary SAR activity: one maintained excitatory activity mainly during deflation and the other receptors showed a tonic discharge during both deflation and inflation. Despite the difference in deflationary SAR firing patterns after veratridine administration, flecainide treatment (6.0 mg/kg) blocked veratridine-induced deflationary SAR stimulation and also caused strong inhibition of the excitatory responses of deflationary SARs to lung deflation. Under these conditions, the average values for deflationary SAR AI were over 90%. The responses of deflationary SARs and deflationary SAR AI to lung deflation were not significantly altered by pretreatment with either 4-AP (0.7 and 2.0 mg/kg) or TEA (2.0 and 6.0 mg/kg). These results suggest that the excitatory effect of lung deflation on deflationary SAR activity is mediated by the activation of flecainide-sensitive Na(+) channels on the nerve terminals of deflationary SARs. 相似文献
4.
Chikako Nishigori Miran Tanaka Shin-ichi Moriwaki Sadao Imamura Hiraku Takebe 《Cancer science》1992,83(11):1172-1178
Skin tumors were produced on the back of hairless mice, HOS (HR/De), by exposure to ultraviolet B light (UVB, 290–320 nm) with 4 different protocols. The first tumors appeared earlier (in 10 weeks in group I and 7 weeks in group III) when initial intense exposure was given, followed by repeated lower-level exposures, than when the mice were exposed to the repeated UV only (in 16 weeks both in group II and group IV). All mice developed skin tumors earlier in the groups given the repeated UV exposures three times a week than in the groups given the exposures twice a week. Most of the skin tumors produced by the UVB exposure were histologically malignant, being transplantable to nude mice, and the cultured cells grown from the tumors were capable of producing tumors when injected into nude mice. The accelerated development of skin tumors by initial intense exposure and short intervals of repeated exposure observed in this study may have implications for humans who expose themselves to intense sunbathing and UV tanning (burning) by fluorescent sun lamps. 相似文献
5.
Hidenori Endo Chikako Nito Hiroshi Kamada Tatsuro Nishi Pak H Chan 《Journal of cerebral blood flow and metabolism》2006,26(12):1479-1489
Recent studies have revealed that the phosphatidylinositol 3-kinase (PI3-K) pathway is involved in apoptotic cell death after experimental cerebral ischemia. The serine-threonine kinase, Akt, functions in the PI3-K pathway and prevents apoptosis by phosphorylation at Ser473 after a variety of cell death stimuli. After phosphorylation, activated Akt inactivates other apoptogenic factors, including glycogen synthase kinase-3beta (GSK3beta), thereby inhibiting cell death. However, the role of Akt/GSK3beta signaling in the delayed death of hippocampal neurons in the CA1 subregion after transient global cerebral ischemia (tGCI) has not been clarified. Transient global cerebral ischemia for 5 mins was induced by bilateral common carotid artery occlusion combined with hypotension. Western blot analysis showed a significant increase in phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) in the hippocampal CA1 subregion after tGCI. Immunohistochemistry showed that expression of phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) was markedly increased in the vulnerable CA1 subregion, but not in the ischemic-tolerant CA3 subregion. Double staining with phospho-GSK3beta (Ser9) and terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling showed different cellular distributions in the CA1 subregion 3 days after tGCI. Phosphorylation of Akt and GSK3beta was prevented by LY294002, a PI3-K inhibitor, which facilitated subsequent DNA fragmentation 3 days after tGCI. Moreover, transgenic rats that overexpress copper/zinc-superoxide dismutase, which is known to be neuroprotective against delayed hippocampal CA1 injury after tGCI, had enhanced and persistent phosphorylation of both Akt and GSK3beta after tGCI. These findings suggest that activation of the Akt/GSK3beta signaling pathway may mediate survival of vulnerable hippocampal CA1 neurons after tGCI. 相似文献
6.
Hiroko Koizumi Chikako Yasui Torn Fukaya Tetsuo Ueda Akira Ohkawara 《Experimental dermatology》1994,3(1):40-44
Abstract Substance P is a neuropeptide which is present in peripheral C nerve endings and released from them. Free nerve endings of C nerve are present in human epidermis. The effects of substance P on the transmembrane signaling system of pig epidermal sheets were previously reported. In these studies, a small amount of cells other than keratinocytes contaminated the epidermal sheets and the species difference from human was also noticed. Therefore we investigated the effects of substance P on cultured normal human epidermal keratinocytes. Alteration of intracellular free calcium (Ca2+) in single living keratinocytes was studied using an inverted fluorescence microscope and Ca2+ -sensitive dye, Fura 2-AM. Treatment of normal human epidermal kertinocytes with substance P resulted in an increase in inositol 1,4,5-trisphosphate and in intracellular Ca2+. Substance P inhibited DNA synthesis of the keratinocytes in a dose-dependent manner. These results are consistent with the view that substance P stimulates phosphatidylinositol-4,5-bisphosphate hydrolysis of human keratinocytes, resulting in inositol 1,4,5-trisphosphate-Ca2+ signal. 相似文献
7.
Yoshimasa Matsuda Shinya Ono Yosuke Otake Shinya Handa Katsumi Kose Tomoyuki Haishi Shigeto Yamada Chikako Uwabe Kohei Shiota 《Magnetic resonance in medical sciences》2007,6(3):139-146
Using 4 and 8-channel super-parallel magnetic resonance (MR) microscopes with a horizontal bore 2.34T superconducting magnet developed for 3-dimensional MR microscopy of the large Kyoto Collection of Human Embryos, we acquired T(1)-weighted 3D images of 1204 embryos at a spatial resolution of (40 microm)(3) to (150 microm)(3) in about 2 years. Similarity of image contrast between the T(1)-weighted images and stained anatomical sections indicated that T(1)-weighted 3D images could be used for an anatomical 3D image database for human embryology. 相似文献
8.
9.
Yuji Okuyama Mitsuhiko Yamada Chikako Kondo Eisaku Satoh Shojiro Isomoto Takashi Shindo Yoshiyuki Horio Masafumi Kitakaze Masatsugu Hori Y. Kurachi 《Pflügers Archiv : European journal of physiology》1998,435(5):595-603
The effects of potassium channel opening drugs and intracellular nucleotides on the ATP-sensitive K+ (KATP) channel composed of SUR2A and Kir6.2 in HEK293T cells were examined using the patch-clamp technique. The SUR2A/Kir6.2 channel
was activated effectively by pinacidil, marginally by nicorandil but not by diazoxide. The pinacidil-activated channel currents
were inhibited by glibenclamide with a K
i value of 160 nM. Upon formation of inside-out (I-O) patches, spontaneous openings of the channels appeared, which were inhibited
by intracellular ATP (ATPi) equipotently in the presence and in the absence of intracellular Mg2+ (Mg2+
i). The channel activity ran-down gradually in I-O patches. The run-down channels could be reactivated by ATPi only in the presence of Mg2+
i. Uridine 5’-diphosphate (UDP) antagonized the ATPi-mediated inhibition of the channel activity before run-down. After run-down, UDP activated the channel without antagonizing
ATPi-mediated channel inhibition. Thus, the SUR2A/Kir6.2 reproduced the major properties of the native cardiac KATP channel well in terms of nucleotide regulation and pharmacology, and therefore can be a useful tool with which to elucidate
the molecular mechanisms characterizing the KATP channel.
Received: 24 October 1997 / Received after revision and accepted: 4 December 1997 相似文献
10.
Toshio Takeuchi Hiroshi Iwasaki Yuko Ohjimi Yasuhiko Kaneko Masako Ishiguro Chikako Fujita Yasusi Mlura Yoshiharu Hiratsuka Kimitaka Sakamoto Masahiro Kikuchi 《Pathology international》1996,46(4):292-297
The cytogenetic and morphologic characteristics of a case with a primitive neuroectodermal tumor (PNET) arising from the left kidney in a 22 year old man are presented. The patient was detected as having a left renal mass with a tumor embolus In the inferior vena cava and multiple pulmonary metastases. A radical nephrectomy with tumor embolectomy of the Inferior vena cava, along with a resection of the pulmonary nodules were performed. Histologic examination revealed a dense proliferation of small round cells with many Homer-Wright type rosettes and perlvascular pseudo-rosettes. Immunohlstochemically, the tumor cells stained strongly positive for HBA71(p30/32M IC2 ), a surface glycopro-teln specific to PNET and Ewlng's sarcoma. In addition, the tumor cells expressed several neural markers (neuron specific enolase, neurofilament, synaptophysin, and Leu-7) and vimentin, while the epithelial, muscular, and lymphocytlc markers were negative in the tumor cells. Cytogenetic analysis of cultured tumor cells showed a reciprocal translocation t(11; 22)(q24; q12) that is considered to be specific to PNET and Ewing's sarcoma. In conclusion, this case suggested that a karyotyping analysis is a useful diagnostic tool for renal PNET, and it may therefore be utilized to help distinguish between difficult cases of small round cell tumors and Wilms' tumor of the kidney. 相似文献