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991.
992.
MHC class I (MHC I) antigen presentation is a ubiquitous process by which cells present endogenous proteins to CD8+ T lymphocytes during immune surveillance and response. Hereditary hemochromatosis protein, HFE, is involved in cellular iron uptake but, while structurally homologous to MHC I, is unable to bind peptides. However, increasing evidence suggests a role for HFE in the immune system. Here, we investigated the impact of HFE on CD8+ T‐lymphocyte activation. Using transient HFE transfection assays in a model of APCs, we show that WT HFE (HFEWT), but not C282Y‐mutated HFE, inhibits secretion of MIP‐1β from antigen‐specific CD8+ T lymphocytes. HFEWT expression also resulted in major decreases in CD8+ T‐lymphocyte activation as measured by 4–1BB expression. We further demonstrate that inhibition of CD8+ T‐lymphocyte activation was independent of MHC I surface levels, β2‐m competition, HFE interaction with transferrin receptor, antigen origin, or epitope affinity. Finally, we identified the α1–2 domains of HFEWT as being responsible for inhibiting CD8+ T‐lymphocyte activation. Our data imply a new role for HFEWT in altering CD8+ T‐lymphocyte reactivity, which could modulate antigen immunogenicity. 相似文献
993.
Mika Adachi Mitsuhiro Sato Mariko Miyazaki Osamu Hotta Koji Hozawa Toshinobu Sato Yoshio Taguma Yukio Katori 《Auris, nasus, larynx》2018,45(6):1206-1213
Objective
Tonsillectomy combined with steroid-pulse therapy is a widely accepted method for the treatment of IgA nephropathy (IgAN) in Japan. However, the indication of tonsillectomy for IgAN is still controversial, and the timing of tonsillectomy is not clearly defined for the protocol of this therapy. Based on the results of a randomized control trial in Japan, the Evidence-Based Clinical Practice Guidelines for IgA nephropathy 2014 (edited in Japan) recommended tonsillectomy combined with steroid-pulse therapy for Grade C1. However, this is not widely accepted worldwide. To clarify the validity and timing of tonsillectomy, we evaluated how the three-consecutive steroid-pulse therapy method affects the tonsil tissues of IgAN patients.Methods
We examined tonsil specimens from 35 IgAN patients and 8 chronic tonsillitis patients. We compared the proportion of follicular area to total tonsillar area and the number of germinal centers between each group on hematoxylin and eosin stained pathological specimens to clarify the histopathological characteristics of tonsils from IgAN patients. Based on these findings, we examined the tonsils of patients after three-consecutive steroid-pulse therapy treatments (n = 34) to determine the influence of this therapy on the tonsil tissues of IgAN patients. Moreover, we observed chronological changes in tonsil tissues after steroid-pulse therapy.Results
The extrafollicular area was enlarged in IgAN patients before steroid-pulse therapy compared with chronic tonsillitis patients. Just after steroid-pulse therapy, the follicles became very small with blurry outlines, and the number of germinal centers was remarkably decreased. With a gradual decrease in oral prednisolone, the tonsil tissue structure was gradually restored.Conclusion
Tonsillectomy combined with steroid-pulse therapy is considered a reasonable treatment for IgAN. Steroid-pulse therapy-induced histological changes in tonsils were transient, indicating tonsillectomy should be performed before or just after steroid-pulse therapy. 相似文献994.
Mika Takahashi Go Sato Naoki Toda Takahiro Azuma Katsuhiko Nakamura Hidetaka Iwasaki Hitomi Miyoshi Kazunori Matsuda Yoshiaki Kitamura Koji Abe Shoichiro Takao Masafumi Harada Noriaki Takeda 《Auris, nasus, larynx》2021,48(3):347-352
ObjectiveThe correlation between enhancement of the vestibulocochlear nerves on gadolinium-enhanced magnetic resonance imaging (MRI) and vestibulocochlear functional deficits was examined in patients with Ramsay Hunt syndrome (RHS).MethodsNineteen patients with RHS who showed herpes zoster oticus, peripheral facial palsy, and vertigo were enrolled. Canal paresis (CP) in the caloric test, abnormal response to ocular and cervical vestibular myogenic potentials (oVEMP and cVEMP), and refractory sensorineural hearing loss were evaluated. MRI images perpendicular to the internal auditory canal were reconstructed to identify the superior (SVN) and inferior vestibular nerves (IVN) and the cochlear nerve (CV). The signal intensity increase (SIinc) of the four-nerve enhancement was calculated as an index.ResultsAmong RHS patients, 79%, 53%, 17% and 26% showed CP in the caloric test, abnormal responses to oVEMP and cVEMP, and refractory sensorineural hearing loss, respectively. SIinc rates of the SVN were significantly increased in RHS patients with CP in the caloric test, and with abnormal responses to oVEMP and cVEMP. SIinc rates of the SVN tended to increase in RHS patients with refractory sensorineural hearing loss (p = 0.052). SIinc rates of the IVN were significantly increased in RHS patients with abnormal responses to oVEMP and cVEMP, and refractory sensorineural hearing loss, but not in those with CP in the caloric test. SIinc rates of the CN were significantly increased in RHS patients with CP in the caloric test, abnormal response to oVEMP and refractory sensorineural hearing loss, but not in those with abnormal response to cVEMP.ConclusionIn patients with RHS, the origin of vertigo may be superior vestibular neuritis, which is affected by reactive varicella-zoster virus from the geniculate ganglion of the facial nerve through the faciovestibular anastomosis. The results also suggested that in some RHS patients, inferior vestibular neuritis contributes to the development of vertigo and that the origin of refractory sensorineural hearing loss is cochlear neuritis. 相似文献
995.
Juho R.H. Raiko Costan G. Magnussen Mika Kähönen Tomi Laitinen Leena Taittonen Jorma S.A. Viikari Olli T. Raitakari Markus Juonala 《Ultrasound in medicine & biology》2010
We examined tracking of ultrasound measurements of vascular structure and function in adulthood using data collected in the 2001 and 2007 follow-ups of Cardiovascular Risk in Young Finns Study. B-mode ultrasound measures of carotid artery intima-media thickness (IMT), carotid artery distensibility (CDist) and brachial artery flow-mediated dilatation (FMD) was obtained on 1809 apparently healthy Finnish adults aged 24 to 39 years in 2001 (1014 females; 795 males). Significant 6-year tracking was observed for IMT (males, r = 0.56; females, r = 0.46), CDist (males, r = 0.35; females, r = 0.36) and FMD (males, r = 0.23; females, r = 0.20). Subjects with 10-year risk of CVD (according to the SCORE risk score) above sex-specific median had improved IMT (r = 0.44; r = 0.57, p = 0.0001) and CDist (r = 0.31; r = 0.40, p = 0.03) tracking compared with those below median. Body mass index (BMI) ≥ 30 kg/m2 decreased tracking of CDist (r = 0.36; r = 0.19, p = 0.01). In conclusion, ultrasound measurements tracked low to moderate over 6-years and was influenced by cardiovascular disease (CVD) risk factor status. (E-mail: juho.raiko@utu.fi) 相似文献
996.
Mika Tada Masahiro Kohno Shigenobu Kasai Yoshimi Niwano 《Journal of Clinical Biochemistry and Nutrition》2010,47(2):162-166
Alleviated melanin formation in the skin through inhibition of tyrosine-tyrosinase reaction is one of the major targets of cosmetics for whitening ability. Since melanin has a pivotal role for photoprotection, there are pros and cons of inhibition of melanin formation. This study applying electron spin resonance (ESR)-spin trapping method revealed that •H and •OH are generated through tyrosine-tyrosinase reaction. When deuterium water was used instead of H2O, the signal of 5,5-dimethyl-1-pyrroline N-oxide (DMPO)-H (a spin adduct of DMPO and •H) greatly decreased, whilst DMPO-OH (a spin adduct of DMPO and •OH) did not. Thus, it is suggested that •H was derived from H2O, and •OH through oxidative catalytic process of tyrosine to dopaquinone. Our study suggests that tyrosinase inhibitors might contribute to alleviate the oxidative damage of the skin by inhibiting •OH generation via the enzyme reaction. 相似文献
997.
Contribution of Asian mouse subspecies Mus musculus molossinus to genomic constitution of strain C57BL/6J, as defined by BAC-end sequence-SNP analysis 下载免费PDF全文
Abe K Noguchi H Tagawa K Yuzuriha M Toyoda A Kojima T Ezawa K Saitou N Hattori M Sakaki Y Moriwaki K Shiroishi T 《Genome research》2004,14(12):2439-2447
MSM/Ms is an inbred strain derived from the Japanese wild mouse, Mus musculus molossinus. It is believed that subspecies molossinus has contributed substantially to the genome constitution of common laboratory strains of mice, although the majority of their genome is derived from the west European M. m. domesticus. Information on the molossinus genome is thus essential not only for genetic studies involving molossinus but also for characterization of common laboratory strains. Here, we report the construction of an arrayed bacterial artificial chromosome (BAC) library from male MSM/Ms genomic DNA, covering approximately 1x genome equivalent. Both ends of 176,256 BAC clone inserts were sequenced, and 62,988 BAC-end sequence (BES) pairs were mapped onto the C57BL/6J genome (NCBI mouse Build 30), covering 2,228,164 kbp or 89% of the total genome. Taking advantage of the BES map data, we established a computer-based clone screening system. Comparison of the MSM/Ms and C57BL/6J sequences revealed 489,200 candidate single nucleotide polymorphisms (SNPs) in 51,137,941 bp sequenced. The overall nucleotide substitution rate was as high as 0.0096. The distribution of SNPs along the C57BL/6J genome was not uniform: The majority of the genome showed a high SNP rate, and only 5.2% of the genome showed an extremely low SNP rate (percentage identity = 0.9997); these sequences are likely derived from the molossinus genome. 相似文献
998.
Takayuki Hirano T. Kumabe Kensuke Murakami Mika Watanabe Reizo Shirane Takashi Yoshimoto 《Child's nervous system》2001,17(4-5):286-289
An 18-year-old boy presented with an immature neurohypophysial teratoma occurring 10 years after total resection of a mature pineal teratoma through an occipital transtentorial approach in 1989. Thorough histological examination had revealed a mature teratoma. He developed panhypopituitarism and diabetes insipidus in 1999. Magnetic resonance imaging revealed a suprasellar tumor occupying the third ventricle. This tumor was totally resected through a frontobasal approach. Histological examination revealed an immature teratoma. This tumor occurred in a different site from the initial tumor and was considered to be de novo and thus a so-called metachronous germ cell tumor. Patients with completely resected mature teratoma require extended follow-up, including periodic magnetic resonance imaging, because of the risk of such a metachronous germ cell tumor. Received: 19 June 2000 Revised: 10 August 2000 相似文献
999.
1000.