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71.
BACKGROUND: In 90% of all cases, Mycobacterium tuberculosis infection results in latency rather than active disease, with the pathogen being contained within granulomatous lesions at the site of primary infection. Failure of this containment leads to reactivation of postprimary tuberculosis (TB). The regional immune processes that sustain the delicate balance with persistent M. tuberculosis, however, remain unclear. METHODS: We compared activation statuses, biological functions, and interactions of host immune cells in human nonprogressive tuberculoma and active cavitary tuberculous lung tissue. RESULTS: Dissection of early granuloma formations revealed differential cellular distribution and activation statuses of distinct cell types in different regions relative to the central caseotic caverna or the tuberculoma in tuberculous lung tissue. In patients with tuberculoma with latent infection, distant parts of lung tissue exhibited strong vascularization and profound proliferative activity, indicating that continuous immune defense is required for mycobacterial containment, which is absent in cavitary tuberculous lung lesions. CONCLUSIONS: We conclude that differential regulation of the local immune response is crucial for the containment of M. tuberculosis and that a continuous antigen-specific cross talk between the host immune system and M. tuberculosis is ensured during latency. This activation requires sufficient supply of nutrients and well-coordinated structural organization, both of which are lost during reactivation of TB.  相似文献   
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The objectives of this prospective epidemiological study were to describe the diagnosis and treatment of respiratory tract infections by Finnish general practitioners and to compare current practice with national evidence-based guidelines. All patients (n = 4386) seeking primary care for a respiratory tract infection for the first time in 30 health centres during 1 week in November 1998 participated in the study. The main outcome measures were the amounts and types of diagnostic tests used and antimicrobials prescribed. Tympanometry was used in 1% of patients with acute otitis media. Ultrasonography, sinus radiography or both were used in 80% of cases of sinusitis and antigen detection or culture for Streptococci in 57% of throat infections. In acute bronchitis, a chest radiograph was taken in 5% of cases and the CRP level determined in 8%. The corresponding figures for pneumonia were 49% and 39%. In pneumonia and throat infection, diagnostic testing was statistically significantly associated with the use of antimicrobials, but not in otitis, sinusitis or acute bronchitis. Diagnostic tests were underused in respiratory tract infections compared to evidence-based recommendations.  相似文献   
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Recent developments of optogenetic tools and fluorescence-based calcium recording techniques enable the manipulation and monitoring of neural circuits on a cellular level. Non-invasive imaging of brain networks, however, requires the application of methods such as blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI), which is commonly used for functional neuroimaging. While BOLD fMRI provides brain-wide non-invasive reading of the hemodynamic response, it is only an indirect measure of neural activity. Direct observation of neural responses requires electrophysiological or optical methods. The latter can be combined with optogenetic control of neuronal circuits and are MRI compatible. Yet, simultaneous optical recordings are still limited to fiber-optic-based approaches. Here, we review the integration of optical recordings and optogenetic manipulation into fMRI experiments. As a practical example, we describe how BOLD fMRI in a 9.4-T small animal MR scanner can be combined with in vivo fiber-optic calcium recordings and optogenetic control in a multimodal setup. We present simultaneous BOLD fMRI and calcium recordings under optogenetic control in rat. We outline details about MR coil configuration, choice, and usage of opsins and chemically and genetically encoded calcium sensors, fiber implantation, appropriate light power for stimulation, and calcium signal detection, to provide a glimpse into challenges and opportunities of this multimodal molecular neuroimaging approach.  相似文献   
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Mobile technology has been increasingly adopted in promotion of mental health among older people. This study assessed the feasibility of a mobile mental wellness training application for individual use and for group work from the perspectives of older adults and social care professionals. The older individuals recruited for the study were participants in a Circle of Friends group and family caregivers' peer support group offered by the communal senior services. The qualitative and quantitative results of interviews, questionnaires, observation, and application usage were reported. Seven older adults started using the application independently at home in parallel with the group activity. This study revealed new information regarding the barriers to the older adults' full adoption of such mobile technologies. The results indicated that there may be potential in the incorporation of mobile technologies in promotion of mental health of older people at group settings.  相似文献   
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