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131.
Joji Tokugawa Narisumi Cho Hiroharu Suzuki Natsuki Sugiyama Osamu Akiyama Yasuaki Nakao Takuji Yamamoto 《PloS one》2015,10(6)
Purpose
To investigate the length variation of the posterior auricular artery and propose a novel classification of the posterior auricular artery based on angiographical appearance.Patients and Methods
A series of 234 consecutive patients who had undergone conventional cerebral angiography was analyzed. The posterior auricular artery was examined on the lateral projection of the external carotid or common carotid arteriography. The posterior auricular artery was classified into four groups by length, using the external auditory canal and the top of the helix as radiographical landmarks. Our proposed classification is as follows: Type A, posterior auricular artery terminates between its origin and the center of the external auditory canal; Type B, posterior auricular artery terminates between the center of the external auditory canal and the top of the helix; Type C, posterior auricular artery terminates between the top of the helix and the vertex; and Type D, posterior auricular artery reaches up to the vertex.Results
A total of 424 (right, 214; left, 210) posterior auricular arteries were analyzed in 111 men and 123 women aged 11 to 91 years (mean, 61.0 years) examined for aneurysms in 78 cases, occlusive vascular diseases in 56, intracranial hemorrhages in 41, tumors in 35, and others in 24. Types A, B, C, and D were found in 15.1%, 34.9%, 48.8%, and 1.2% of the patients, respectively.Conclusion
A novel classification of the posterior auricular artery identifies four types based on its length on cerebral angiography. 相似文献132.
Takuya Kotani Tohru Takeuchi Takaaki Ishida Ryota Masutani Kentaro Isoda Kenichiro Hata Shuzo Yoshida Shigeki Makino Toshiaki Hanafusa 《PloS one》2015,10(10)
BackgroundActivated CD8+ T cells play an important role in the pathogenesis of dermatomyositis (DM) with interstitial pneumonia (IP). Serum CD8+ T-cell activator, LIGHT, and Th1/Th2/Th17 cytokines were measured in DM-IP patients and compared with clinical parameters to investigate their usefulness.MethodsThe correlations between the clinical findings and serum LIGHT and Th1/Th2/Th17 cytokine levels were investigated in 21 patients with DM-IP (14 with rapidly progressive IP [RPIP] and 7 with chronic IP [CIP], including 4 fatal cases of IP).ResultsThe median serum LIGHT level was 119 (16–335.4) pg/ml, which was higher than that in healthy control subjects and DM patients without IP. The median serum IL–6 level was 14.7 (2.4–154.5) pg/ml (n = 13). The other cytokines were detected in only a few patients. The median serum LIGHT level in DM-RPIP patients (156 [49.6–335.4] pg/ml) was significantly higher than that in DM-CIP patients (94.3 [16–164.2] pg/ml) (P = 0.02). The serum IL–6 level did not correlate with either progression or outcome of DM-IP. ROC curve analysis determined a serum LIGHT level of ≥120 pg/ml to be the cut-off value for the rapid progression of DM-IP. Serum LIGHT levels correlated significantly with %DLco (R = 0.55, P = 0.04) and total ground-glass opacity scores (R = 0.72, P = 0.0002). The serum LIGHT level significantly decreased to 100.5 (12.4–259.3) pg/ml 4 weeks after treatment initiation (P = 0.04).ConclusionsThe serum LIGHT level may be a promising marker of disease progression and severity in patients with DM-IP. 相似文献
133.
Ryosuke Tateishi Nobuko Akiyama Maki Miyauchi Riko Yoshinaga Hiroki Sasanuma Takashi Kudo Miki Shimbo Masahiro Shinohara Koji Obata Jun-ichiro Inoue Masaki Shirakawa Dai Shiba Hiroshi Asahara Nobuaki Yoshida Satoru Takahashi Hironobu Morita Taishin Akiyama 《PloS one》2015,10(10)
Gravity change affects many immunological systems. We investigated the effects of hypergravity (2G) on murine thymic cells. Exposure of mice to 2G for three days reduced the frequency of CD4+CD8+ thymocytes (DP) and mature medullary thymic epithelial cells (mTECs), accompanied by an increment of keratin-5 and keratin-8 double-positive (K5+K8+) TECs that reportedly contain TEC progenitors. Whereas the reduction of DP was recovered by a 14-day exposure to 2G, the reduction of mature mTECs and the increment of K5+K8+ TEC persisted. Interestingly, a surgical lesion of the inner ear’s vestibular apparatus inhibited these hypergravity effects. Quantitative PCR analysis revealed that the gene expression of Aire and RANK that are critical for mTEC function and development were up-regulated by the 3-day exposure and subsequently down-regulated by the 14-day exposure to 2G. Unexpectedly, this dynamic change in mTEC gene expression was independent of the vestibular apparatus. Overall, data suggest that 2G causes a temporary reduction of DP and a persistent reduction of mature mTECs in a vestibular system-dependent manner, and also dysregulates mTEC gene expression without involving the vestibular system. These data might provide insight on the impact of gravity change on thymic functions during spaceflight and living. 相似文献
134.
The physical habitat characteristics associated with spatial distribution patterns of the freshwater mussel Pronodularia japanensis, which is used for oviposition by the Tokyo bitterling Tanakia tanago, were investigated in a small stream within a Tokyo bitterling protected area. The distribution of the mussels was found to be in an under-dispersed, non-random spatial pattern. Mussel occurrence correlated negatively with sediment softness, and positively with flow velocity, while mussel abundance was associated negatively with sediment softness and positively with sediment type (particle size). Furthermore, mussels were scarce in riverbed areas with a lack of sediment. These correlations suggest that the population dynamics of mussels and Tokyo bitterling may be influenced by changes in stream sediment conditions. To conserve the symbiosis between Tokyo bitterlings and mussels, a suitable benthic environment is required. 相似文献
135.
Haifeng Tang Yan Yan Zhe Feng Reynalda K. de Jesus Lihu Yang Dorothy A. Levorse Karen A. Owens Taro E. Akiyama Raynald Bergeron Gino A. Castriota Thomas W. Doebber Kenneth P. Ellsworth Michael E. Lassman Cai Li Margaret S. Wu Bei B. Zhang Kevin T. Chapman Sander G. Mills Joel P. Berger Alexander Pasternak 《Bioorganic & medicinal chemistry letters》2010,20(20):6088-6092
A new series of thiazole-substituted 1,1,1,3,3,3-hexafluoro-2-propanols were prepared and evaluated as malonyl-CoA decarboxylase (MCD) inhibitors. Key analogs caused dose-dependent decreases in food intake and body weight in obese mice. Acute treatment with these compounds also led to a drop in elevated blood glucose in a murine model of type II diabetes. 相似文献
136.
Daichi Ogawara Taketo Muroya Kazumi Yamauchi Taka-aki Iwamoto Yoshihiko Yagi Yoshihiro Yamashita Shou Waga Masahiro Akiyama Hisaji Maki 《DNA Repair》2010,9(1):90-95
REV3 is the catalytic subunit of DNA polymerase ζ (pol ζ), which is responsible for the damage-induced mutagenesis that arises during error-prone translesion synthesis in eukaryotes. The related REV3L genes in human and mouse encode proteins of approximately 350 kDa, twice as large as yeast REV3, but full-length REV3L has not been identified in any vertebrate cell. We report that Xenopus laevis REV3L encodes a 352-kDa protein that has high overall amino acid sequence similarity to its mammalian counterparts, and, for the first time in a vertebrate species, we have detected putative REV3L polypeptides of 300 and 340 kDa in X. laevis oocytes. Only the 300-kDa form is stored in eggs, where its concentration of about 65 pM is much lower than those of other replication and repair proteins including the accessory pol ζ subunit REV7. In fertilized eggs, the levels of this polypeptide did not change until neurula; the larger 340-kDa form first appeared at stages after gastrula, suggesting a pattern of regulation during development. These observations indicate the existence of REV3L as a scarce protein, of approximately the full predicted size, whose level may impose severe constraints on the assembly of pol ζ in X. laevis. 相似文献
137.
Hideya Ando Yoko Niki Masaki Yoshida Masaaki Ito Kaoru Akiyama Jin-Hwa Kim Tae-Jin Yoon Jeung-Hoon Lee Mary S. Matsui Masamitsu Ichihashi 《Pigment cell & melanoma research》2010,23(1):129-133
There are many techniques for evaluating melanosome transfer to keratinocytes but the spectrophotometric quantification of melanosomes incorporated by keratinocyte phagocytosis has not been previously reported. Here we describe a new method that allows the spectrophotometric visualization of melanosome uptake by normal human keratinocytes in culture. Fontana-Masson staining of keratinocytes incubated with isolated melanosomes showed the accumulation of incorporated melanosomes in the perinuclear areas of keratinocytes within 48 h. Electron microscopic observations of melanosomes ingested by keratinocytes revealed that many phagosomes containing clusters of melanosomes or their fragments were localized in the perinuclear area. A known inhibitor of keratinocyte phagocytosis which inhibits protease-activated receptor-2, i.e., soybean trypsin inhibitor, decreased melanosome uptake by keratinocytes in a dose-dependent manner. These data suggest that our method is a useful model to quantitate keratinocyte phagocytosis of melanosomes visually in vitro. 相似文献
138.
139.
Nakayama EE Carpentier W Costagliola D Shioda T Iwamoto A Debre P Yoshimura K Autran B Matsushita S Theodorou I 《Immunogenetics》2007,59(6):511-515
Polymorphisms in human genes have been shown to affect the rate of disease progression to acquired immune deficiency syndrome
in human immunodeficiency virus type 1 (HIV-1)-infected individuals. Recently, tripartite motif 5α (TRIM5α) was identified
as a factor that confers resistance to HIV-1 infection in Old World monkey cells. Subsequently, Sawyer et al. (Curr Biol 16:95–100,
2006) reported a single nucleotide polymorphism (H43Y) in the human TRIM5α gene and TRIM5α protein with 43Y was found to lose its ability to restrict HIV-1. In the present study, we reevaluated effects
of this allele on in vitro anti-HIV-1 activity as well as on HIV-1 disease progression in European and Asian cohorts of HIV-1-infected
individuals. Our epidemiological and molecular biological findings clearly indicate H43Y has a very minor effect on anti-HIV-1
activity of TRIM5α, suggesting that this allele is immaterial, at least in HIV-1-infected Europeans and Asians. 相似文献
140.