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21.
Legionella endocarditis is extremely uncommon, and embolic phenomena have never been reported. We report the first case of Legionella micdadei prosthetic valve endocarditis complicated by brain abscess. A 57-y-old immunocompromised woman with a history of mitral valve replacement developed confusion and left-sided weakness. Brain magnetic resonance imaging showed a 3-cm peripheral-enhancing mass. Transoesophageal echocardiography suggested a perivalvular abscess. Blood cultures and valve cultures were negative. She was diagnosed with 16S rRNA polymerase chain reaction and silver stain, and was discharged with levofloxacin after a redo mitral valve replacement. Twelve cases of Legionella endocarditis were reviewed. Only one case had a native valve, and her endocarditis occurred after pneumonia. All cases were cured. The duration of antibiotic therapy was variable. Legionella species should be considered in the differential diagnosis of culture-negative endocarditis in both immunocompetent and immunocompromised patients. Molecular techniques and silver impregnation stains are useful, especially when cultures using buffered charcoal-yeast extract agar are negative.  相似文献   
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A 73-year-old man was hospitalized for unstable angina pectoris with no history of myocardial infarction. After undergoing percutaneous coronary intervention, left ventriculography incidentally revealed a cavity in the anterior wall, and echocardiography found the cavity wall to be dyskinetic. Myocardial contrast echocardiography revealed that the wall of the cavity was surrounded by myocardial tissue with low perfusion. Furthermore, radial strain in the wall of the cavity was low. Myocardial scintigraphy showed a localized defect on the anterior wall. The patient was finally diagnosed as true aneurysm after asymptomatic and localized myocardial infarction, and has since been followed up by echocardiography in the outpatient clinic.  相似文献   
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Activity‐dependent reorganizations of central neuronal synapses are thought to play important roles in learning and memory. Although the precise mechanisms of how neuronal activities modify synaptic connections in neurons remain to be clarified, the activity‐induced neuronal presynaptic proteins such as synaptotagmin1 may contribute to the onset of synaptic remodeling. To understand better the physiological roles of synaptotagmin1, we first examined the prolonged effects of neuronal stimulation capable of inducing synaptotagmin1 on the distribution of a postsynaptic proteins (PSD) protein Homer1c by immunostaining. Previously we found that glutamate stimulation induced other postsynaptic proteins, such as postsynaptic density‐95 (PSD95), a biphasic change with an initially diffuse distribution after 30 min to 1 hr, followed by reassembly to more than the original level after 4–8 hr, suggesting that glutamate stimulation induces a global biphasic alteration in synaptic structures. To dissect further the functions of synaptotagmin1 in the activity‐induced synaptic remodeling, short hairpin RNA (shRNA) vectors that specifically block the expression of endogenous synaptotagmin1 were constructed. When the shRNA of synaptotagmin1 was introduced to the neurons, the activity‐induced changes were almost completely suppressed. We found that synaptotagmin1 contributes to the postsynaptic remodeling in a retrograde manner. Our data indicate that synaptotagmin1 regulates the activity‐induced biphasic changes of post‐ and presynaptic sites. © 2013 Wiley Periodicals, Inc.  相似文献   
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Tumor-specific peptide-pulsed dendritic cells (DC) were administered via different routes to a group of patients with head and neck cancers. The migration and homing patterns of such antigen-stimulated cells was carefully studied employing single photon emission computed tomography (SPECT). The DC administered directly into the nasal submucosa quickly migrated very rapidly to the regional neck lymph nodes in the neck. However, after inoculation of the cells into the palatine tonsils, the DCs remained close to the site of administration and did not migrate to the regional lymph nodes or to other mucosal regions. After nasal submucosal administration of the DC, tumor-antigen-specific cytotoxic T cells were detected in the ipsilaterals but not in the contra lateral lymph nodes. These results suggest that after antigen processing, the regional lymph nodes serve as inductive sites for development of mucosal immune responses and for induction of memory cells during the local immunological responses in the nasopharyngeal-associated lymphoid tissue in man.  相似文献   
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Purpose

Although mental health problems such as depression after disasters have been reported, positive psychological factors after disasters have not been examined. Recently, the importance of positive affect to our health has been recognised. We therefore investigated the frequency of laughter and its related factors among residents of evacuation zones after the Great East Japan Earthquake of 2011.

Methods

In a cross-sectional study on 52,320 participants aged 20 years and older who were included in the Fukushima Health Management Survey in Japan’s fiscal year 2012, associations of the frequency of laughter with changes in lifestyle after the disaster, such as a changed work situation, the number of family members, and the number of address changes, and other sociodemographic, psychological, and lifestyle factors were examined using logistic regression analysis. The frequency of laughter was assessed using a single-item question: “How often do you laugh out loud?”

Results

The proportion of those who laugh almost every day was 27.1%. Multivariable models adjusted for sociodemographic, psychological, and lifestyle factors demonstrated that an increase in the number of family members and fewer changes of address were significantly associated with a high frequency of laughter. Mental health, regular exercise, and participation in recreational activities were also associated with a high frequency of laughter.

Conclusion

Changes in lifestyle factors after the disaster were associated with the frequency of laughter in the evacuation zone. Future longitudinal studies are needed to examine what factors can increase the frequency of laughter.
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PURPOSE: To investigate whether genomic DNA can be purified in sufficient quantity and quality from the oral cavity. METHODS: One milliliter of peripheral blood and saliva were collected. The buccal and lingual mucosal cells were also obtained using 10 strokes with a swab or a toothbrush, respectively. All materials were centrifuged and the cells were lysed by adding sodium dodecyl-sulfate and proteinase K. The DNAs were extracted with phenol and precipitated with ethanol followed by electrophoresing on 0.8% agarose gel. The purified DNAs were digested with restriction enzyme Dpn I and Mbo I, respectively. Amplification of the IL-1A gene by PCR was carried out using the purified DNAs and electrophoresing on polyacrylamide gel. RESULTS: DNA was obtained from lingual mucosal cells collected with a toothbrush. Only about one-thirtieth of the recovered DNA was of non-human origin (bacterial contaminants from the oral cavity). Judging from the PCR amplifications of the IL-1A gene, the DNA extracted from lingual cells was of sufficient quality, in all respects indistinguishable from the DNAs extracted from the other specimen, such as peripheral blood, saliva and buccal mucosal cells collected with a swab, and in sufficient quantity. Our results indicate that it is possible to purify DNAs from lingual mucosal cells collected with a toothbrush in a simple and safe manner. Compared to DNA samples from patients by blood extraction, the described method also had the advantage of being painless and not inducing mental distress.  相似文献   
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