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81.
Cryptosporidium parvum oocyst viability was determined by a dye permeability assay using a flow cytometric method. Oocysts were inoculated into small chambers with soil and biosolids. Oocysts extracted from soil and biosolids were then stained with propidium iodide (PI) and labeled with a fluorescein isothiocyanate (FITC)-conjugated monoclonal antibody. The oocyst population in each sample was determined using forward and side scatter plots, then further analyzed with fluorescence. A red and green fluorescence detector using gates established single populations of unstained, PI-stained, or FITC-labeled oocysts. No statistical difference was observed between viability of oocysts extracted from soil and biosolids as determined by either flow cytometry or microscopy. The location of excysted oocysts was changed in forward and side scatter plots. Results indicated that, although oocysts are not identified if they excyst, the flow cytometric method could be used to determine oocyst viability from spiked environmental samples.  相似文献   
82.
Sinusoidal obstruction syndrome (SOS)/hepatic veno-occlusive disease (VOD) is a well-documented complication after hematopoietic stem cell transplantation (HSCT). Transabdominal ultrasonography (US) enables the visualization of blood flow abnormalities and is therefore useful for the diagnosis of SOS/VOD. We herein prospectively evaluated accuracy of a novel US diagnostic scoring system of SOS/VOD based on US findings. We carried out US in 106 patients on day 14 and when SOS/VOD was suspected after allogeneic HSCT. Among 106 patients, 10 patients (9.4%) were diagnosed as SOS/VOD by Baltimore or Seattle criteria. According to univariate analysis of 17 US findings (US-17 screening), we established a novel scoring system (HokUS-10) consisting of 10 parameters, such as gallbladder wall thickening, ascites, and blood flow signal in the paraumbilical vein. The sensitivity and specificity were 100% and 95.8%, respectively. Diagnostic performance of the HokUS-10 was significantly better than US-17 screening. In 4 of 10 patients US detection of SOS/VOD preceded to clinical diagnosis. The HokUS-10 scoring system is useful in the diagnosis of SOS/VOD; however, our results should be validated in other cohorts.  相似文献   
83.
Signal regulatory protein α (SIRPα) is expressed predominantly on type 2 conventional dendritic cells (cDC2s) and macrophages. We previously showed that mice systemically lacking SIRPα were resistant to experimental autoimmune encephalomyelitis (EAE). Here, we showed that deletion of SIRPα in CD11c+ cells of mice (SirpaΔDC mice) also markedly ameliorated the development of EAE. The frequency of cDCs and migratory DCs (mDCs), as well as that of Th17 cells, were significantly reduced in draining lymph nodes of SirpaΔDC mice at the onset of EAE. In addition, we found the marked reduction in the number of Th17 cells and DCs in the CNS of SirpaΔDC mice at the peak of EAE. Whereas inducible systemic ablation of SIRPα before the induction of EAE prevented disease development, that after EAE onset did not ameliorate the clinical signs of disease. We also found that EAE development was partially attenuated in mice with CD11c+ cell-specific ablation of CD47, a ligand of SIRPα. Collectively, our results suggest that SIRPα expressed on CD11c+ cells, such as cDC2s and mDCs, is indispensable for the development of EAE, being required for the priming of self-reactive Th17 cells in the periphery as well as for the inflammation in the CNS.  相似文献   
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Peripheral blood monocytes extravasate and differentiate into tissue macrophages to mediate effective local defence, but how tissue-specific stimuli and environments may influence their functions remains unknown. Here, we found that peripheral blood monocytes gained the ability to produce granulocyte-macrophage colony-stimulating factor (GM-CSF) upon exposure to breast milk and differentiated into CD1+ dendritic cells (DCs) in the presence of exogenous interleukin-4 (IL-4) alone. This in vitro observation appeared physiologically relevant since macrophages that were freshly isolated from breast milk were also found to produce GM-CSF spontaneously. Furthermore, in contrast to peripheral blood monocytes that differentiated into DCs only in the presence of both exogenous GM-CSF and IL-4, differentiation of breast milk macrophages into DCs was induced by incubation with exogenous IL-4 alone. These IL-4-stimulated breast milk macrophages were efficient in stimulating T cells, suggesting their potential role in mediating T-cell-dependent immune responses in situ. On the other hand, unexpected expression of DC-SIGN, a DC-specific receptor for human immunodeficiency virus (HIV), even in unstimulated breast milk macrophages, may favour HIV infection, resulting in an increased risk of mother-to-infant vertical transmission of the virus via breast milk. Thus, tissue-specific development of macrophages is often linked to effective local immunity, but may potentially provide an opportunity for a pathogen to spread and transmit.  相似文献   
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88.

Objective

Deep brain stimulation (DBS) can provide insights into the workings of the basal ganglia (BG) by interfering with their function. In patients with Parkinson's disease (PD) treated with DBS of the subthalamic nucleus, we studied the effect of DBS on scanning eye movements.

Methods

In the visual memory task, subjects viewed images of various complexities for later recall. In visual search tasks, subjects looked for and fixated one odd target ring, embedded among 48 Landolt rings, which either stood out or not from the distractors. We compared the parameters of scanning saccades when DBS was on and off.

Results

In the visual memory task, DBS increased the amplitude of saccades scanning simple but not complex drawings. In the visual search tasks, DBS showed no effect on saccade amplitude or frequency.

Conclusions

Saccades when viewing simple images were affected by DBS since they are internally guided saccades, for which the involvement of BG is large. In contrast, saccades when viewing complex images or during visual search, made with the help of visual cues in the images (externally guided saccades) and less dependent on BG, were resistant to the effect of DBS.

Significance

DBS affects saccades differentially depending on the task.  相似文献   
89.

Background

Responses to continuous theta burst stimulation (cTBS) applied to the human primary motor cortex are highly variable between individuals. However, little is known about how to improve the after-effects of cTBS by adjusting the protocol characteristics.

Objective

We examined whether current directions adopted in the measurement of cortical motor excitability indexed as motor evoked potentials (MEPs) affect the responses to cTBS. We also tested whether the stimulus intensity of cTBS influences the after-effects.

Methods

Thirty-one healthy volunteers participated. The after-effects of cTBS with the conventional intensity of 80% of individual active motor threshold (AMT) (cTBS80%) were tested by measuring MEP amplitudes induced by not only posterior-anterior (PA) but also anterior-posterior (AP) and biphasic (PA-AP) currents. We also investigated cTBS with 65% AMT (cTBS65%) and 100% AMT (cTBS100%) in subjects who showed depression of MEP amplitudes after cTBS80%, as well as cTBS65% in subjects in whom facilitation of MEPs was induced by cTBS80%.

Results

Current directions in MEP measurement had no influence on the cTBS responses. In subjects whose MEPs were depressed by cTBS80%, cTBS100% partly induced MEP facilitation, while cTBS65% abolished the after-effects. In subjects who showed MEP facilitation by cTBS80%, cTBS65% partly induced MEP depression.

Conclusions

Stimulus intensity of cTBS influenced the responses to cTBS, and lowering stimulus intensity induced the expected after-effects of cTBS in some subjects.  相似文献   
90.

Background

The mental health community in Japan had started reviewing the country??s disaster mental health guidelines before the Great East Japan Earthquake, aiming to revise them based on evidence and experience accumulated in the last decade. Given the wealth of experience and knowledge acquired in the field by many Japanese mental health professionals, we decided to develop the guidelines through systematic consensus building and selected the Delphi method.

Methods

After a thorough literature review and focus group interviews, 96 items regarding disaster mental health were included in Delphi Round 1. Of 100 mental health professionals experienced in disaster response who were invited to participate, 97 agreed. The appropriateness of each statement was assessed by the participants using a Likert scale (1: extremely inappropriate, 9: very appropriate) and providing free comments in three rounds. Consensus by experts was defined as an average score of ??7 for which ??70% of participants assigned this score, and items reaching consensus were included in the final guidelines.

Results

Overall, of the 96 items (89 initially asked and 7 added items), 77 items were agreed on (46 items in Round 1, and 19 positive and 12 negative agreed on items in Round 2). In Round 2, three statements with which participants agreed most strongly were: 1) A protocol for emergency work structure and information flow should be prepared in normal times; 2) The mental health team should attend regular meetings on health and medicine to exchange information; and 3) Generally, it is recommended not to ask disaster survivors about psychological problems at the initial response but ask about their present worries and physical condition. Three statements with which the participants disagreed most strongly in this round were: 1) Individuals should be encouraged to provide detailed accounts of their experiences; 2) Individuals should be provided with education if they are interested in receiving it; and 3) Bad news should be withheld from distressed individuals for fear of causing more upset.

Conclusions

Most items which achieved agreement in Round 1 were statements described in previous guidelines or publications, or statements regarding the basic attitude of human service providers. The revised guidelines were thus developed based on the collective wisdom drawn from Japanese practitioners?? experience while also considering the similarities and differences from the international standards.  相似文献   
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