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71.
Kawabata T Kinoshita M Inatsu A Habu Y Nakashima H Shinomiya N Seki S 《Hepatology (Baltimore, Md.)》2008,48(5):1586-1597
Immune functions of liver natural killer T (NKT) cells induced by the synthetic ligand alpha-galactosylceramide enhanced age-dependently; hepatic injury and multiorgan dysfunction syndrome (MODS) induced by ligand-activated NKT cells were also enhanced. This study investigated how aging affects liver innate immunity after common bacteria DNA stimulation. Young (6 weeks) and old (50-60 weeks) C57BL/6 mice were injected with CpG oligodeoxynucleotides (CpG-ODN), and the functions of liver leukocytes were assessed. A CpG-ODN injection into the old mice remarkably increased tumor necrosis factor (TNF) production in Kupffer cells, and MODS and lethal shock were induced, both of which are rarely seen in young mice. Old Kupffer cells showed increased Toll-like receptor-9 expression, and CpG-ODN challenge augmented TNF receptor and Fas-L expression in liver NKT cells. Experiments using mice depleted of natural killer (NK) cells by anti-asialoGM1 antibody (Ab), perforin knockout mice, and mice pretreated with neutralizing interferon (IFN)-gamma Ab demonstrated the important role of liver NK cells in antitumor immunity. The production capacities of old mice for IFN-gamma, IFN-alpha, and perforin were much lower than those of young mice, and the CpG-induced antitumor cytotoxicity of liver NK cells lessened. Lethal shock and MODS greatly decreased in old mice depleted/deficient in TNF, FasL, or NKT cells. However, depletion of NK cells also decreased serum TNF levels and FasL expression of NKT cells, which resulted in improved hepatic injury and survival, suggesting that NK cells are indirectly involved in MODS/lethal shock induced by NKT cells. Neutralization of TNF did not reduce the CpG-induced antitumor effect in the liver. CONCLUSION: Hepatic injury and MODS mediated by NKT cells via the TNF and FasL-mediated pathway after CpG injection increased, but the antitumor activity of liver NK cells decreased with aging. 相似文献
72.
73.
Yamazaki T Asanoi H Ueno H Yamada K Takagawa J Kameyama T Hirai T Nozawa T Inoue H 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2005,27(2-3):241-249
The present study was designed to develop a method to continuously measure Holter electrocardiogram (ECG) and physical activity in terms of metabolic costs to examine circadian dynamics of RR intervals and physical activity in patients with heart failure. A total of 7 healthy subjects and 3 heart failure patients performed cardiopulmonary exercise test using four-stage graded treadmill walking at 0% grade to examine whether the acceleration signals in the vertical direction could reflect actual body energy expenditure during physical activity. Then, using this new method, 24-hr monitorings of ECG and physical activity were performed in 24 inpatients with heart failure while they were allowed to walk around freely. Our results showed the integral of rectified acceleration signals was closely correlated with actual metabolic cost in all subjects. Instantaneous changes in heart rate were quite concordant with physical activity. As compared with the asymptomatic patients (n = 12), the symptomatic patients (n = 12) had lower energy expenditure during 8-hr daytime periods but higher mean heart rate. Furthermore, a more prominent ultradian rhythm of circadian changes in heart rate and physical activity was found in 50% of all subjects studied. The simultaneous analysis of Holter ECG and physical activity as the same time series revealed that in patients with heart failure, sympathovagal balance shifted toward sympathotonic conditions and their physical activity could become subject to intrinsic ultradian dynamics of body's homeostasis. 相似文献
74.
Genotypes at chromosome 22q12-13 are associated with HIV-1-exposed but uninfected status in Italians 总被引:2,自引:0,他引:2
Kanari Y Clerici M Abe H Kawabata H Trabattoni D Caputo SL Mazzotta F Fujisawa H Niwa A Ishihara C Takei YA Miyazawa M 《AIDS (London, England)》2005,19(10):1015-1024
OBJECTIVE: Despite multiple and repeated exposures to HIV-1, some individuals possess no detectable HIV genome and show T-cell memory responses to the viral antigens. HIV-1-reactive mucosal IgA detected in such uninfected individuals suggests their possible immune resistance against HIV. We tested if the above HIV-1-exposed but uninfected status was associated with genetic markers other than a homozygous deletion of the CCR5 gene. METHODS: Based on our mapping in chromosome 15 of a gene controlling the production of neutralizing antibodies in a mouse retrovirus infection, we genotyped 42 HIV-1-exposed but uninfected Italians at polymorphic loci in the syntenic segment of human chromosome 22, and compared them with 49 HIV-1-infected and 47 uninfected healthy control individuals by a closed testing procedure. RESULTS: A significant association was found between chromosome 22q12-13 genotypes and a putative dominant locus conferring anti-HIV-1 immune responses in the exposed but uninfected individuals. Distributions of linkage disequilibrium across chromosome 22 also differed between the exposed but uninfected and two other phenotypic groups. CONCLUSIONS: The data indicated the presence of a new genetic factor associated with the HIV-1-exposed but uninfected status. 相似文献
75.
Yushiro Endo Shin-ya Kawashiri Shimpei Morimoto Ayako Nishino Momoko Okamoto Sosuke Tsuji Ayuko Takatani Toshimasa Shimizu Remi Sumiyoshi Takashi Igawa Tomohiro Koga Naoki Iwamoto Kunihiro Ichinose Mami Tamai Hideki Nakamura Tomoki Origuchi Yukitaka Ueki Tamami Yoshitama Nobutaka Eiraku Naoki Matsuoka Akitomo Okada Keita Fujikawa Hideo Otsubo Hirokazu Takaoka Hiroaki Hamada Tomomi Tsuru Shuji Nagano Arinobu Yojiro Toshihiko Hidaka Yoshifumi Tada Atsushi Kawakami 《Medicine》2021,100(1)
We aimed to evaluate the utility of a simplified ultrasonography (US) scoring system, which is desired in daily clinical practice, among patients with rheumatoid arthritis (RA) receiving biological/targeted synthetic disease-modifying antirheumatic drugs (DMARDs).A total of 289 Japanese patients with RA who were started on tumor necrosis factor inhibitors, abatacept, tocilizumab, or Janus kinase inhibitors between June 2013 and April 2019 at one of the 15 participating rheumatology centers were reviewed. We performed US assessment of articular synovia over 22 joints among bilateral wrist and finger joints, and the 22-joint (22j)-GS and 22-joint (22j)-PD scores were evaluated as an indicator of US activity using the sum of the GS and PD scores, respectively.The top 6 most affected joints included the bilateral wrist and second/third metacarpophalangeal joints. Therefore, 6-joint (6j)-GS and -PD scores were defined as the sum of the GS and PD scores from the 6 synovial sites over the aforementioned 6 joints, respectively. Although the 22j- or 6j-US scores were significantly correlated with DAS28-ESR or -CRP scores, the correlations were weak. Conversely, 6j-US scores were significantly and strongly correlated with 22j-US scores not only at baseline but also after therapy initiation.Using a multicenter cohort data, our results indicated that a simplified US scoring system could be adequately tolerated during any disease course among patients with RA receiving biological/targeted synthetic DMARDs. 相似文献
76.
Hirao K Yano K Horikawa T Suzuki K Kawabata M Motokawa K Suzuki F Kawara T Hiejima K 《Journal of electrocardiology》1999,32(1):65-71
We report on a patient with uncommon-type atrioventricular (AV) nodal reentrant tachycardia with a short tachycardia cycle length (235-270 ms), in whom transient wide QRS tachycardia with both left bundle branch block and right bundle branch block aberrancy were followed by narrow QRS complexes. In addition, His-ventricular (H-V) block and a sudden prolongation of the H-V interval occurred during the tachycardia. As the determinant of these unusual findings, the possibility that the anterograde limb of the reentry circuit has an enhanced AV nodal conduction property is discussed, as is the clinical significance of this type of tachycardia. 相似文献
77.
Maki Akasu M.D. Keijiro Saku M.D. Masanori Okabe M.D. Koichi Handa M.D. Kunihiro Matsuo M.D. Shiro Jimi Ph.D. Kikuo Arakawa M.D. 《The International journal of angiology》1995,4(3):169-171
Typical angioid streaks were found on routine ophthalmologic examination in a 42-year-old female with yellowish, coalescing papules on her neck without any symptoms. Biopsy of the cutaneous lesion showed degeneration and fragmentation of the elastic fibers and many basophilic-stained calcifications in mid-dermis, which are consistent with pseudoxanthoma elasticum. Twenty-four-hour Holter electrocardiography (ECG) showed sinus arrest for 2.5 seconds, and an electrophysiological study revealed sinus nodal dysfunction (sick sinus syndrome), whereas all of the coronary arteries were intact, despite a treadmill stress ECG test showing significant ST depressions. The association of pseudoxanthoma elasticum and sick sinus syndrome is very rare. One possible explanation for this association here is that the degeneration of elastic fiber in endomysium of the sino-atrial node may have affected heart conduction systems, resulting in sick sinus syndrome.Part of this work was presented at the 76th Japanese Circulation Society Kyushu Meeting, Japan, June 18, 1994 相似文献
78.
J. Fu H. Ikegami Y. Kawaguchi T. Fujisawa Y. Kawabata Y. Hamada H. Ueda M. Shintani K. Nojima N. Babaya Q.-J. Shen Y. Uchigata T. Urakami Y. Omori K. Shima T. Ogihara 《Diabetologia》1998,41(2):228-232
Summary An insulin-dependent diabetes mellitus (IDDM)-susceptibility gene (IDDM13) has recently been mapped to a region of distal chromosome 2q, which is syntenic to the region of mouse chromosome 1 containing
a murine susceptibility gene for IDDM, Idd5. To determine the contribution of this region to IDDM disease susceptibility further and to narrow the region for positional
cloning of susceptibility genes, we have studied the association of distal chromosome 2q with IDDM in the genetically distinct
Japanese population. A 137 mobility unit (mu) allele at D2S137 locus was significantly associated with IDDM (odds ratio 1.92, p = 0.0016). Other markers, D2S301 and D2S143, located in the same region were not associated with IDDM, indicating that IDDM13 is in linkage disequilibrium with D2S137, but not with D2S301 or D2S143. The association of D2S137 with IDDM was observed in patients lacking one of two high risk HLA alleles, DQB1
*
0303 and DQB1
*
0401, but not in patients with either of these alleles. The frequency of high risk HLA alleles was significantly lower in patients
with the susceptible allele at D2S137, suggesting that IDDM13 contributes to IDDM susceptibility in subjects without high risk genotypes at IDDM1. Demonstration of allelic association of D2S137 with IDDM localizes IDDM13 in the close vicinity (< 2 centiMorgans) of D2S137, greatly facilitating fine structure mapping and positional cloning of IDDM13. [Diabetologia (1998) 41: 228–232]
Received: 27 March 1997 and in revised form: 3 October 1997 相似文献
79.
A new mutation in exon 12 of the gp91-phox gene leading to cytochrome b- positive X-linked chronic granulomatous disease 总被引:1,自引:0,他引:1
Azuma H; Oomi H; Sasaki K; Kawabata I; Sakaino T; Koyano S; Suzutani T; Nunoi H; Okuno A 《Blood》1995,85(11):3274-3277
We have previously reported a patient with cytochrome b-positive X- linked chronic granulomatous disease. Although the O2- production of neutrophils from the patient was completely defective, we presented data suggesting that the patient's cytochrome b was present at a normal level and possibly had normal spectroscopic features. Thus, to look for a mutation in the cytochrome b heavy chain (gp91-phox) gene, DNA analysis of gp91-phox cDNA derived from this patient was performed. As a result, we found that five nucleotides (1521 through 1525) within exon 12 were deleted, and a new sequence of eight nucleotides was inserted. This mutation converted Gln507-Lys508-Thr509 into His-Ile-Trp- Ala. Mismatched polymerase chain reaction showed that the mother has both wild and mutated alleles, confirming that this case was transmitted in an X-linked fashion. This mutation is different from those previously reported by others. The translocation of p47-phox and p67-phox to the membrane fraction occurred, indicating the complete formation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. We conclude that this case suggests that the structure encoded on exon 12 of gp91-phox is important for electron transfer. 相似文献
80.
Synthesis,Properties, and Doping Behavior of Optically Active Polythiophenes Bearing a Bornyl Group 下载免费PDF全文
Atsushi Matsumura Kohsuke Kawabata Hiromasa Goto 《Macromolecular chemistry and physics.》2015,216(9):931-938
Polythiophenes bearing a bornyl group as a side chain are synthesized. The polymers, which consist of multiple thiophenes and a substituted aromatic ring in the repeat unit, demonstrate right‐handed helicity in the film state. Results of energy level measurements show good agreement with the density functional theory calculation results for the model compounds. In situ electron spin resonance (ESR) studies indicate that increasing the number of unsubstituted thiophene units in the repeat unit increases susceptibility for the dopants. The chiral charge carriers are confirmed with ESR and circular dichroism spectroscopy measurements.