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121.
122.
Yamamoto M Haruna T Ueda C Asano Y Takahashi H Iduhara M Takaki S Yasui K Matsuo Y Arimura A 《Archives of dermatological research》2009,301(10):739-746
Recently, we have reported that the pathophysiological features of dermatitis induced by the repeated application with Dermatophagoides farinae (Df) extract ointment in NC/Nga mice were similar to those observed in the patients with atopic dermatitis. In the present
study, we first examined whether the application of Df in other mouse strains could induce dermatitis. The repeated application
of Df body (Dfb) ointment to the barrier-disrupted back of ICR, C57BL/6, and Balb/c mice did not cause any apparent skin lesions,
although transient increase in serum immunoglobulin E (IgE) levels during antigen application was observed. On the other hand,
in NC/Nga mice, dermatitis scores and serum IgE levels increased remarkably, and then these changes sustained for at least
10 days after stopping of antigen elicitation. Using NC/Nga mice, we investigated the contribution of scratching behavior
to the development and maintenance of Dfb-induced dermatitis. In correlation with the increase in scratching behavior, erythema,
hemorrhage, edema, scarring, erosion and excoriation were observed. Cutting off the hind toenails of mice exhibiting chronic
skin lesions dramatically alleviated the dermatitis. From these findings, the onset of skin lesions and its chronically sustained
course in Dfb-induced dermatitis in NC/Nga mice were closely associated with increased scratching behavior. 相似文献
123.
Akitaka Tanaka Shigeki Nakamura Masafumi Seki Kenji Fukudome Naoki Iwanaga Yoshifumi Imamura Taiga Miyazaki Koichi Izumikawa Hiroshi Kakeya Katsunori Yanagihara Shigeru Kohno 《Clinical and Vaccine Immunology : CVI》2013,20(7):977-985
Coinfection with bacteria is a major cause of mortality during influenza epidemics. Recently, Toll-like receptor (TLR) agonists were shown to have immunomodulatory functions. In the present study, we investigated the effectiveness and mechanisms of the new TLR4 agonistic monoclonal antibody UT12 against secondary pneumococcal pneumonia induced by coinfection with influenza virus in a mouse model. Mice were intranasally inoculated with Streptococcus pneumoniae 2 days after influenza virus inoculation. UT12 was intraperitoneally administered 2 h before each inoculation. Survival rates were significantly increased and body weight loss was significantly decreased by UT12 administration. Additionally, the production of inflammatory mediators was significantly suppressed by the administration of UT12. In a histopathological study, pneumonia in UT12-treated mice was very mild compared to that in control mice. UT12 increased antimicrobial defense through the acceleration of macrophage recruitment into the lower respiratory tract induced by c-Jun N-terminal kinase (JNK) and nuclear factor kappaB (NF-κB) pathway-dependent monocyte chemoattractant protein 1 (MCP-1) production. Collectively, these findings indicate that UT12 promoted pulmonary innate immunity and may reduce the severity of severe pneumonia induced by coinfection with influenza virus and S. pneumoniae. This immunomodulatory effect of UT12 improves the prognosis of secondary pneumococcal pneumonia and makes UT12 an attractive candidate for treating severe infectious diseases. 相似文献
124.
Yukari Sekiguchi Sonoko Misawa Kazumoto Shibuya Satsuki Mitsuma Shigeki Hirano Shigeki Ohmori Shunsuke Koga Yuta Iwai Minako Beppu Satoshi Kuwabara 《Clinical neurophysiology》2013,124(7):1465-1469
ObjectiveTo elucidate the features of sensory nerve involvement in Fisher syndrome (FS), this study extensively investigated sensory electrophysiology.MethodsIn 47 consecutive FS patients, results of sensory nerve conduction studies in the median, ulnar and sural nerves, soleus H-reflexes, and median or tibial somatosensory-evoked potentials (SEP) were reviewed. Because of the large effects of age on amplitude of sensory nerve action potentials (SNAP), we strictly defined reduction of SNAP amplitudes by using a nomogram which age and amplitude obtained from 87normal subjects.ResultsIn routine nerve conduction studies, SNAP amplitude was reduced only in 32% of the patients, and conduction velocity was decreased in 2%. In contrast, soleus H-reflexes were frequently absent or reduced (67%). SEPs were abnormal only in 17%.ConclusionsIn FS, absent soleus H-reflexes are the most frequent electrophysiologic abnormalities, whereas SNAPs amplitudes are rarely affected. The pattern is characterized by predominant involvement of group Ia afferents with relatively preserved cutaneous afferents without evidence suggestive of demyelination.SignificanceThe major targets of immune attack by anti-GQ1b antibodies in FS appear to be group Ia neurons in the dorsal root ganglia, and this is presumably responsible for ataxia and areflexia in FS. 相似文献
125.
Abnormalities of rate-corrected QT intervals in Parkinson's disease-a comparison with multiple system atrophy and progressive supranuclear palsy 总被引:4,自引:0,他引:4
Deguchi K Sasaki I Tsukaguchi M Kamoda M Touge T Takeuchi H Kuriyama S 《Journal of the neurological sciences》2002,199(1-2):31-37
A number of patients with Parkinson's disease (PD) and multiple system atrophy (MSA), in whom sudden death does occur occasionally, have QT or rate-corrected QT (QTc) interval prolongation on electrocardiogram (ECG). Although these QT or QTc interval abnormalities are likely related to autonomic dysfunction, the pathophysiology remains unknown. The aim of this study was to compare the degree of QTc interval prolongation among akinetic-rigid syndromes, namely PD and related disorders, and to evaluate the relationship between QTc prolongation and severity of autonomic dysfunction. Thirty-four patients with PD, 22 with MSA, 11 with progressive supranuclear palsy (PSP) and 30 healthy controls underwent standard autonomic function tests, and electrocardiography variables (RR, QT and QTc intervals) were measured by an ECG recorder with an automated analyzer. The relationship between QTc interval and cardiovascular reflex tests were also analyzed. Orthostatic hypotension and decreased heart rate in response to respiratory stimuli were prominent in MSA, while these were relatively mild in PD. Unlike the RR and QT intervals, the QTc interval significantly differed among all groups (p<0.01). The QTc interval was significantly prolonged in PD (409+/-17 ms; p<0.001) and MSA (404+/-14 ms; p<0.05) compared with healthy controls (394+/-19 ms). Neither autonomic dysfunction nor QTc interval prolongation was evident in PSP. QTc intervals and cardiovascular reflexes did not correlate, except for Valsalva ratio. The QTc interval was obviously prolonged in PD patients to an extent that could not be accounted for simply by autonomic dysfunction levels. MSA patients showed slightly prolonged QTc intervals in spite of marked cardiovascular autonomic dysfunction. Abnormalities of the QTc may reflect the degeneration of cardioselective sympathetic and parasympathetic neurons that cannot be fully captured by cardiovascular autonomic function tests. 相似文献
126.
When the neural tube of avian embryos is separated from the notochord and floor plate, motoneurons in the spinal cord fail to develop. In order to investigate the factors involved in this phenomenon, cell proliferation activity and cell death were observed following paramedian incision of the neural tube at the level of the segmental plate using colchicine, BrdU, and TUNEL methods. If the notochord and/or floor plate produces a substance(s) that promotes cell division in the basal plate neuroepithelium or that supports the survival of the motoneuron's neuroblasts, mitotic figures should not be present in the neuroepithelium nor should substantial cell death be observed in the ventral aspect of the notochord- and floor plate-deprived neural tube. Surprisingly, however, neither result was observed in the present experiments, with the exception of a considerable amount of homogeneously distributed cell death. Neuroepithelial cells continued to proliferate and gave rise to neuroblasts. Nevertheless, motoneurons failed to develop, and the neural tube was enveloped by only the basement membrane of the alar plate (S. Hirano and H. Tanaka, 1994,Dev. Growth Differ.36, 481–488). These morphological results revealed that the cause of the development of the anterior horn lacking a neural tube in the notochord- and neural tube-eliminated embryos is not the elimination of the source of the surviving factor(s) of the motoneuron's neuroblasts, but rather the elimination of the signals to induce the motoneurons, derived from the notochord and/or floor plate. The larger amount of cell death in the neural tube on the experimental side suggests that a nonspecific survival factor(s), necessary for the survival of a variety of types of neuroblasts, is also produced by the notochord and/or floor plate. 相似文献
127.
Shimoji K Aoki S Nakanishi A Suzuki M Hori M Sato S Hoshito H Kyogoku S Cho N Ozaki Y Suzuki M Kuwatsuru R Sasai K 《Japanese journal of radiology》2012,30(2):116-119
Purpose
The aim of this study was to elucidate the distribution of estimated glomerular filtration rate (eGFR) values in patients who underwent gadolinium-based contrast agent (GBCA)-enhanced magnetic resonance imaging (MRI) at different types of hospitals.Materials and methods
We retrospectively studied 2,550 patients who underwent MRI at five institutions. We recorded the date and value of each patient??s eGFR test. The distribution of eGFR values was compared with that in the general Japanese population.Results
A total of 84.3% of patients had their eGFRs evaluated before GBCA-enhanced MRI. Of these, 84.7% were evaluated within 3?months before the GBCA-enhanced MRI, and 1.3% were evaluated on the day of the GBCA-enhanced MRI. A total of 87.2% of patients tested had an eGFR of ??60?ml/min/1.73?m2; 12.8% had an eGFR of <60 and ??30?ml/min/1.73?m2, and no patients had an eGFR of <30?ml/min/1.73?m2.Conclusion
The rate of renal function evaluation differed among hospitals. The prevalence of low eGFR values was greater in Juntendo Tokyo Koto Geriatric Medical Center than in the other hospitals, and the prevalence of low eGFR values was greater in patients who underwent GBCA-enhanced MRI than in the general Japanese population. 相似文献128.
Staging laparoscopy leads to rapid induction of chemotherapy for unresectable pancreatobiliary cancers 下载免费PDF全文
Daisuke Hashimoto Akira Chikamoto Kazuya Sakata Shigeki Nakagawa Hiromitsu Hayashi Masaki Ohmuraya Masahiko Hirota Naoya Yoshida Toru Beppu Hideo Baba 《Asian journal of endoscopic surgery》2015,8(1):59-62
Preoperatively evaluating the resectability of pancreatobiliary cancers is difficult. The aim of this study was to investigate the benefit of staging laparoscopy in unresectable pancreatobiliary cancers. Between 2010 and 2013, 25 patients with pancreatobiliary cancers underwent staging laparoscopy after conventional tumor staging; they were compared with 10 patients who had unresectable or metastatic tumors that were found during laparotomy. Staging laparoscopy did not show unresectable factors in 11 patients, and resections were performed in these patients. Unresectable factors were found in other 14 patients who underwent staging laparoscopy. In these patients, chemotherapy was started after median postoperative day 3 (range, 2–10 days). This period was significantly longer in patients who received unnecessary laparotomy; chemotherapy was started after median postoperative day 11 (range, 6–15 days). These results suggest that staging laparoscopy, while avoiding laparotomy with unsuccessful resection, can lead to rapid induction of chemotherapy for unresectable pancreatobiliary cancers. 相似文献
129.
Shinichi Nakamura Nobuyuki Kurobe Shigeki Kashimoto Tomio Ohue Yoshiyuki Takase Masanao Shimizu 《Antimicrobial agents and chemotherapy》1983,24(1):54-60
The pharmacokinetics of AT-2266 (1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1,8-naphthyridine- 3-carboxylic acid) were studied in various experimental animals and compared in a number of aspects with those of norfloxacin. Both agents were administered orally. The mean peak plasma levels of AT-2266 in mice, rats, and dogs (given a single dose of 50 mg/kg for mice and rats and 25 mg/kg for dogs) were 2.39, 1.63, and 5.00 mug/ml, respectively, with elimination half-lives of 2.24, 2.81, and 5.76 h. The respective mean plasma levels of norfloxacin at similar dosages were 0.510, 0.410, and 0.700 mug/ml; elimination half-lives were 1.40, 2.35, and 6.06 h. In dogs repeatedly dosed with 25 mg of AT-2266 per kg every 12 h, the mean peak plasma levels after the third and fifth doses were about 1.4 times those after the first dose. The binding rates of AT-2266 and norfloxacin to plasma of mice, rats, and dogs and to human serum ranged from 27.6 to 40.2% and 39.8 to 44.2%, respectively. In rats receiving a single dose of 50 mg/kg, the respective mean peak levels of AT-2266 in plasma, lung, muscle, and kidney were 2.47, 4.60, 5.35, and 33.9 mug/ml or g, whereas those of norfloxacin were 0.234, 0.390, 0.272, and 2.05 mug/ml or g. AT-2266 was widely distributed in tissues of dogs and monkeys after repeated dosage. The respective 24-h recoveries of AT-2266 from urine of mice, rats, and dogs after single doses of 50, 50, and 25 mg/kg were 56.6, 40.5, and 64.1%, and recoveries of norfloxacin at these doses were 4.40, 2.91, and 5.34%. The respective 24-h recoveries of AT-2266 from bile and feces of rats given a single dose of 50 mg/kg were 2.47 and 52.7%. Bioautography of plasma and urine indicated that AT-2266 was metabolized to but a slight degree. The results indicate that AT-2266 is better than norfloxacin in oral absorption and similar to the latter in stability to metabolic inactivation. 相似文献