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91.
Suppression of IFN-gamma production in atopic group at the acute phase of RSV infection 总被引:2,自引:0,他引:2
Hideo Kaneko Eiko Matsui Tsutomu Asano Zenichiro Kato Takahide Teramoto Minako Aoki Norio Kawamoto Li Ai Lian Kimiko Kasahara Naomi Kondo 《Pediatric allergy and immunology》2006,17(5):370-375
Several studies have suggested that respiratory syncytial virus (RSV) bronchiolitis induced the change of cytokine production profile in childhood. We sought to determine whether the RSV-induced cytokine production was affected by the patient's atopic background. We quantified interferon-gamma (IFN-gamma) and interleukin (IL)-4 in the supernatant of peripheral blood mononuclear cells (PBMCs) cultured for 24 h and in the presence of phytohemaglutinin (PHA), IL-12, or IL-18, from 14 infants who were divided into two groups, those who are non-atopic and an atopic group. In RSV-infected infants with atopic diseases, IFN-gamma production from IL-12- or especially IL-18-stimulated PBMCs was subtotally suppressed in the acute phase, whereas in RSV-infected infants without atopic diseases IFN-gamma production was not suppressed on acute phase. The IFN-gamma suppression observed in the atopic group is not caused by the immaturity of an infant's immune system since reduced IFN-gamma production to RSV is not observed in the infants of non-atopic group. IFN-gamma suppression in regard to RSV infection might be caused by some genetic factor involved in the development of atopic disease such as IL-18 signal cascade. 相似文献
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93.
Postoperative bleeding risk after gastric endoscopic submucosal dissection during antithrombotic drug therapy
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94.
Effect of finish line design on stress distribution in bilayer and monolithic zirconia crowns: a three‐dimensional finite element analysis study
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Shoko Miura Shin Kasahara Shinobu Yamauchi Hiroshi Egusa 《European journal of oral sciences》2018,126(2):159-165
This study evaluated the influence of different finish line designs and abutment materials on the stress distribution of bilayer and monolithic zirconia crowns using three‐dimensional finite element analysis (FEA). Three‐dimensional models of two types of zirconia premolars – a yttria‐stabilized zirconia framework with veneering ceramic and a monolithic zirconia ceramic – were used in the analysis. Cylindrical models with the finish line design of the crown abutments were prepared with three types of margin curvature radius (CR): CR = 0 (CR0; shoulder margin), CR = 0.5 (CR0.5; rounded shoulder margin), and CR = 1.0 (CR1.0; deep chamfer margin). Two abutment materials (dentin and brass) were analyzed. In the FEA model, 1 N was loaded perpendicular to the occlusal surface at the center of the crown, and linear static analysis was performed. For all crowns, stress was localized to the occlusal loading area as well as to the axial walls of the proximal region. The lowest maximum principal stress values were observed when the dentin abutment with CR0.5 was used under a monolithic zirconia crown. These results suggest that the rounded shoulder margin and deep chamfer margin, in combination with a monolithic zirconia crown, potentially have optimal geometry to minimize occlusal stress. 相似文献
95.
96.
This report describes a unique case of a 56-year-old female who suffered from recurrent stroke after double mechanical valve replacement. During the four years after the surgery, she remained in normal sinus rhythm, received adequate anticoagulation therapy, and no apparent left atrial thrombus was detected. She underwent redo surgery to prevent further stroke after fourth instance of cerebral infarction. Intraoperative findings revealed a ‘dome-shaped’ pannus formation covering the sewing ring of the mitral prosthesis circumferentially, probably leading to clot formation and repeated infarctions. She has been stroke free for three years after pannus resection. 相似文献
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98.
Zhenwei Su Xinliang Zhou Stephen H. Loukin W. John Haynes Yoshiro Saimi Ching Kung 《Pflügers Archiv : European journal of physiology》2009,458(5):861-867
Mechanosensitive (MS) ion channels likely underlie myriad force-sensing processes, from basic osmotic regulation to specified
sensations of animal hearing and touch. Albeit important, the molecular identities of many eukaryotic MS channels remain elusive,
let alone their working mechanisms. This is in stark contrast to our advanced knowledge on voltage- or ligand-sensitive channels.
Several members of transient receptor potential (TRP) ion channel family have been implicated to function in mechanosensation
and are recognized as promising candidate MS channels. The yeast TRP homolog, TRPY1, is clearly a first-line force transducer.
It can be activated by hypertonic shock in vivo and by membrane stretch force in excised patches under patch clamp, making
it a useful model for understanding TRP channel mechanosensitivity in general. TRPY1 offers two additional research advantages:
(1) It has a large (∼300 pS) unitary conductance and therefore a favorable S/N ratio. (2) Budding yeast allows convenient
and efficient genetic and molecular manipulations. In this review, we focus on the current research of TRPY1 and discuss its
prospect. We also describe the use of yeast as a system to express and characterize animal TRP channels. 相似文献
99.
Naoyuki Iizuka Akiko Suzuki Kayoko Nozawa-Inoue Yoshiro Kawano B. G. T. L. Nandasena Takashi Okiji Takeyasu Maeda 《Journal of anatomy》2009,214(2):267-274
Caveolae are involved in clathrin-independent endocytosis, transcytosis, signal transduction, and tumor suppression – all of which depend on their main constituent protein caveolin families. The periodontal Ruffini ending has been reported to develop a caveola-like structure on the cell membrane of both the axon terminals and Schwann sheaths, suggesting the existence of an axon–Schwann cell interaction in the periodontal Ruffini endings. However, little information is available concerning the functional significance of these caveolae. The present study was undertaken to examine the immunolocalization of caveolin-1, -3 (Cav-1, Cav-3) and Ca2+ -ATPase in the periodontal Ruffini endings of the rat incisor. Decalcified sections of the upper jaws were processed for immunocytochemistry at the levels of light and electron microscopy. Some immunostained sections were treated with histochemistry for nonspecific cholinesterase (nChE) activity. Observations showed the periodontal Ruffini endings were immunopositive for Cav-1, but not Cav-3. Immunoreactive products for Cav-1 were confined to caveola-like structures in the cell membranes of the cytoplasmic extensions and cell bodies of the terminal Schwann cells associated with the periodontal Ruffini endings. However, the axonal membranes of the terminals did not express any Cav-1 immunoreaction. Double staining with Ca2+ -ATPase and either protein gene product 9.5 (PGP 9.5) or S-100 protein disclosed the co-localization of immunoreactions in the axonal branches of the periodontal Ruffini endings, but not in the terminal Schwann cells. As Ca2+ plays an important role in mechanotransduction, these characteristic immunolocalizations show Cav-1/Ca2+ -ATPase might be involved in the quick elimination of intracellular Ca2+ in mechanotransduction. 相似文献
100.