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981.
Y Yamashita M Takahashi S Kanazawa C Charnsangavej S Wallace 《Gastrointestinal radiology》1992,17(2):161-166
We evaluated parenchymal changes of the liver in 92 patients (41 peripheral types and 51 hilar types) with cholangiocarcinomas studied by bolus-enhanced computed tomography (CT). In 39% of patients with the peripheral type, a wedge-shaped increased enhancement of the liver was observed peripheral to the tumor on bolus-enhanced CT. Tumor was observed in all cases. In 58.8% of patients with the hilar type, a segmental or lobar increased degree of enhancement of the liver was observed, but the tumor was demonstrated in only 58.8%. Atrophy was accompanied by areas of increased enhancement in 80% of hilar type and 25% of peripheral type. Areas of increased degree of enhancement corresponded to a wedged-shaped perfusion defect on CT during arterial portography. On magnetic resonance imaging (MRI), those lesions showed hyperintensity on T2-weighted images. Most of these changes were considered to be due to reversible hepatic parenchymal ischemia secondary to portal vein invasion by the tumor. 相似文献
982.
Ishibashi Y Shimada T Sakane T Takahashi N Sugamori T Ohhata S Inoue S Katoh H Sano K Murakami Y Hashimoto M 《Journal of the American College of Cardiology》2000,36(5):1605-1611
OBJECTIVES: We examined whether a relationship exists between the vasoconstrictive response to endogenous nitric oxide (NO) synthesis inhibition and the severity of heart failure in patients with congestive heart failure (CHF). BACKGROUND: Controversy exists as to whether the vasoconstrictive response to NO synthesis inhibition in patients with CHF is comparable to that in normal subjects or is enhanced. METHODS: Forearm blood flow (FBF) and calculated forearm vascular conductance (FVC) were obtained using plethysmography before and after administration of the NO synthesis inhibitor L-NMMA (NG-monomethyl-L-arginine) in 40 patients with CHF due to dilated cardiomyopathy and in 16 normal control subjects. Basal plasma B-type natriuretic peptide (BNP) and nitric oxide concentrations were measured in all subjects. RESULTS: Plasma BNP and nitrite/nitrate (NOx) levels in the patients group were significantly greater and baseline FBF was significantly less. Administration of L-NMMA significantly decreased FBF and FVC in both groups. The percent changes in FBF (%FBF) and FVC (%FVC) from the baseline after L-NMMA correlated significantly with plasma BNP level (%FBF: r = 0.72; %FVC: r = 0.76; both p < 0.001). Percent changes in both FBF and FVC were greater in patients with BNP > or = 100 pg/ml than in normal subjects; however, in patients with BNP < 100 pg/ml they were comparable to those in normal subjects. CONCLUSIONS: Vasoconstrictive response to L-NMMA in patients with CHF was preserved or enhanced in proportion to the basal plasma BNP level, indicating a close relationship between the contribution of endogenous NO to basal vasomotor tone and the severity of heart failure. 相似文献
983.
Nobuko Mayumi Eri Watanabe Yoshihiko Norose Eiji Watari Seiji Kawana Teunis B. H. Geijtenbeek Hidemi Takahashi 《European journal of immunology》2013,43(1):270-280
Human skin contains the following two distinct DC subsets: (i) Langerhans cells (LCs), expressing Langerin but not DC‐specific intercellular adhesion molecule‐3‐grabbing nonintegrin (DC‐SIGN), are predominantly localized in the epidermis; and (ii) dermal DCs, expressing DC‐SIGN but not Langerin, are observed mainly in the dermis. It is not known whether localization in the epidermis provides cues for LC differentiation. Here, we show that E‐cadherin expressed by epidermal keratinocytes (KCs) is crucial for differentiation of LCs. Monocytes differentiated into LC‐like cells in presence of IL‐4, GM‐CSF, and TGF‐β1. However, these LC‐like cells expressed not only Langerin but also DC‐SIGN. Notably, co‐culturing of these LC‐like cells with KCs expressing E‐cadherin or recombinant E‐cadherin strongly decreased expression of DC‐SIGN and further induced a phenotype similar to purified epidermal LCs. Moreover, pretreatment of LC‐like cells with anti‐E‐cadherin‐specific antibody completely abolished their Langerin expression, indicating the requirement of E‐cadherin–E‐cadherin interactions for the differentiation into Langerin+ cells. These findings suggest that E‐cadherin expressed by KCs provide environmental cues that induce differentiation of LCs in the epidermis. 相似文献
984.
Aki Tsuruhara Yuko Nagata Masaya Suzuki Koji Inui Ryusuke Kakigi 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2013,226(3):347-355
Psychophysical and visual evoked potential (VEP) studies have shown that spatial frequency of a visual stimulus affects contrast sensitivity and VEPs in humans. However, it is not clear whether and how the effect of spatial frequency varies among cortical areas. Considering that all visual inputs to the retina could be expressed as a sum of sinusoidal gratings of different spatial frequencies, the effect of spatial frequency must be clarified to separate the brain activity specific to each visual stimulus. In order to examine the effect of spatial frequency on different cortical areas, the present study compared cortical responses to sinusoidal gratings of seven different spatial frequencies using magnetoencephalography (MEG). MEG waveforms of twelve healthy adults in response to sinusoidal gratings of 0.3–18.1 cycles per degree were subjected to a multi-dipole analysis. As a result, the effect of spatial frequency was significant on the first peak latency and amplitude of the source activity around V1 and V2 but not on the source activity around V3 and V6, indicating that the effect of spatial frequency varies across different visual areas in the human brain. Our results also suggest that the responses in V1 and V2 that have a peak around 90 ms and that of V6 peaking around 120 ms should be separated to investigate the stimulus-specific cortical response, particularly when examining effects of spatial frequency on the response latency. 相似文献
985.
986.
Objective : The purpose of this study is to construct the cross-sectional head circumference growth curves, intended for clinical use, for the Japanese from birth to 18 years of age. Subjects and methods : Two sets of the national survey data on head circumference and height were utilized for the study: (1) The 1990 data collected by the Japanese Ministry of Health and Welfare on children below 7 years of age ( n = 16 621, 8511 males, 8110 females). (2) The 1992-1994 data collected by the Research Institute of Human Engineering for Quality Life on children from 7 to 18 years of age ( n = 10 183, 5610 males, 4573 females). We used the LMS method to obtain the 3rd, 10th, 25th, 50th, 75th, 90th and 97th percentile values for each age and gender. Results and conclusions : The results showed a persistent positive secular trend in head circumference in Japanese children of both genders. Comparison of these data with those of recent Caucasian studies revealed ethnic difference in head circumference, with Japanese having relatively larger head circumference for height as compared with Caucasians. 相似文献
987.
Aki Tsuchiyagaito Masaya Misaki Obada Al Zoubi Tulsa Investigators Martin Paulus Jerzy Bodurka 《Human brain mapping》2021,42(4):922
Rumination, repetitively thinking about the causes, consequences, and one''s negative affect, has been considered as an important factor of depression. The intrusion of ruminative thoughts is not easily controlled, and it may be useful to visualize one''s neural activity related to rumination and to use that information to facilitate one''s self‐control. Real‐time fMRI neurofeedback (rtfMRI‐nf) enables one to see and regulate the fMRI signal from their own brain. This proof‐of concept study utilized connectivity‐based rtfMRI‐nf (cnf) to normalize brain functional connectivity (FC) associated with rumination. Healthy participants were instructed to brake or decrease FC between the precuneus and the right temporoparietal junction (rTPJ), associated with high levels of rumination, while engaging in a self‐referential task. The cnf group (n = 14) showed a linear decrease in the precuneus‐rTPJ FC across neurofeedback training (trend [112] = −0.180, 95% confidence interval [CI] −0.330 to −0.031, while the sham group (n = 14) showed a linear increase in the target FC (trend [112] = 0.151, 95% CI 0.017 to 0.299). Although the cnf group showed a greater reduction in state‐rumination compared to the sham group after neurofeedback training (p < .05), decoupled precuneus‐rTPJ FC did not predict attenuated state‐rumination. We did not find any significant aversive effects of rtfMRI‐nf in all study participants. These results suggest that cnf has the capacity to influence FC among precuneus and rTPJ of a ruminative brain circuit. This approach can be applied to mood and anxiety patients to determine the clinical benefits of reduction in maladaptive rumination. 相似文献
988.
Yoko Uchida Fujiya Gomi Shigeo Murayama Hiroshi Takahashi 《The American journal of pathology》2013,182(5):1718-1726
989.
Toshiro Kitagawa Takuya Hattori Kazuhiro Sentani Atsuhiro Senoo Yuto Fujii Shinya Takahashi Wataru Yasui Yukiko Nakano Yasuki Kihara 《Journal of Cardiovascular Computed Tomography》2021,15(2):175-179
BackgroundAnti-inflammatory therapy targeting interleukin (IL)-1β reduced cardiovascular events in a randomized trial. We evaluated the relationship between IL-1β mRNA expression in epicardial adipose tissue (EAT) and clinically-assessed coronary atherosclerosis on computed tomography (CT).MethodsWe studied 45 patients before cardiac surgery (coronary artery bypass grafting [CABG], n ?= ?18; non-CABG, n ?= ?27). EAT volume, the coronary calcium score (CCS), and the presence of non- and/or partially-calcified coronary plaques (NCPs) and high-risk coronary plaques (HRPs; minimum CT density <30 Hounsfield units and vascular remodeling index >1.1) on CT angiography were assessed. EAT samples were obtained during cardiac surgery. IL-1β mRNA expression in EAT was measured using quantitative real-time PCR and normalized to that of β-actin in each patient.ResultsThere was no difference in IL-1β mRNA levels between patients who were scheduled for CABG and non-CABG surgery or among subgroups based on the CCS. However, patients with NCPs (median [interquartile range], 4.1[2.0-11.6]E-4 versus 1.8[0.6-4.5]E-4, p ?= ?0.024) and HRP (7.6[3.0-20.4]E-4 versus 1.9[0.7-4.3]E-4, p ?= ?0.0023) had higher IL-1β mRNA levels than those without these plaques. On multivariate analysis adjusted for age, sex, coronary risk factors, statin therapy, CCS, and EAT volume, the presence of HRPs was significantly correlated with elevated IL-1β mRNA levels in EAT (β ?= ?0.39, p ?= ?0.047).ConclusionOur data suggest a contribution of EAT to coronary atherosclerosis through molecular behavior, such as IL-1β gene expression, which may be a new therapeutic target. 相似文献
990.
Kanako Iwasaki Tomoyuki Fujiyama Shinya Nakata Minjeong Park Chika Miyoshi Noriko Hotta-Hirashima Aya Ikkyu Miyo Kakizaki Fumihiro Sugiyama Seiya Mizuno Manabu Abe Kenji Sakimura Satoru Takahashi Hiromasa Funato Masashi Yanagisawa 《The Journal of neuroscience》2021,41(12):2733
Sleep is regulated in a homeostatic manner. Sleep deprivation increases sleep need, which is compensated mainly by increased EEG δ power during non-rapid eye movement sleep (NREMS) and, to a lesser extent, by increased sleep amount. Although genetic factors determine the constitutive level of sleep need and sleep amount in mice and humans, the molecular entity behind sleep need remains unknown. Recently, we found that a gain-of-function Sleepy (Slp) mutation in the salt-inducible kinase 3 (Sik3) gene, which produces the mutant SIK3(SLP) protein, leads to an increase in NREMS EEG δ power and sleep amount. Since Sik3Slp mice express SIK3(SLP) in various types of cells in the brain as well as multiple peripheral tissues from the embryonic stage, the cell type and developmental stage responsible for the sleep phenotype in Sik3Slp mice remain to be elucidated. Here, we generated two mouse lines, synapsin1CreERT2 and Sik3ex13flox mice, which enable inducible Cre-mediated, conditional expression of SIK3(SLP) in neurons on tamoxifen administration. Administration of tamoxifen to synapsin1CreERT2 mice during late infancy resulted in higher recombination efficiency than administration during adolescence. SIK3(SLP) expression after late infancy increased NREMS and NREMS δ power in male synapsin1CreERT2; Sik3ex13flox/+ mice. The expression of SIK3(SLP) after adolescence led to a higher NREMS δ power without a significant change in NREMS amounts. Thus, neuron-specific expression of SIK3(SLP) after late infancy is sufficient to increase sleep.SIGNIFICANCE STATEMENT The propensity to accumulate sleep need during wakefulness and to dissipate it during sleep underlies the homeostatic regulation of sleep. However, little is known about the developmental stage and cell types involved in determining the homeostatic regulation of sleep. Here, we show that Sik3Slp allele induction in mature neurons in late infancy is sufficient to increase non-rapid eye movement sleep amount and non-rapid eye movement sleep δ power. SIK3 signaling in neurons constitutes an intracellular mechanism to increase sleep. 相似文献