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51.
52.

Background

In 2011, a unique Q fever vaccination campaign targeted people at risk for chronic Q fever in the southeast of the Netherlands. General practitioners referred patients with defined cardiovascular risk-conditions (age >15 years). Prevalence rates of those risk-conditions were lacking, standing in the way of adequate planning and coverage estimation. We aimed to obtain prevalence rates retrospectively in order to estimate coverage of the Q fever vaccination campaign.

Methods

With broad search terms for these predefined risk-conditions, we extracted patient-records from a large longitudinal general-practice research-database in the Netherlands (IPCI-database). After validation of these records, obtained prevalence rates (stratified for age and sex) extrapolated to the Q fever high-incidence area population, gave an approximation of the size of the targeted patient-group. Coverage calculation addressed people actually screened by a pre-vaccination Q fever skin test and serology (coverage) and patients referred by their general practitioners (adjusted-coverage) in the 2011 campaign.

Results

Our prevalence estimate of any risk-condition was 3.1% (lower-upper limits 2.9-3.3%). For heart valve defects, aorta aneurysm/prosthesis, congenital anomalies and endocarditis, prevalence was 2.4%, 0.6%, 0.4% and 0.1%, respectively. Estimated number of eligible people in the Q fever high-incidence area was 11,724 (10,965-12,532). With 1330 people screened for vaccination, coverage of the vaccination campaign was 11%. For referred people, the adjusted coverage was 18%. Coverage was lowest among the very-old and highest for people aged 50–70 years.

Conclusion

The estimated coverage of the vaccination campaign was limited. This should be interpreted in the light of the complexity of this target-group with much co-morbidity, and of the vaccine that required invasive pre-vaccination screening. Calculation of prevalence rates of risk-conditions based on the IPCI-database was feasible. This procedure proved an efficient tool for future use, when prevalence estimates for policy, implementation or surveillance of subgroup-vaccination or other health-care interventions are needed.  相似文献   
53.
Here, we report evidence for oscillatory bi-directional interactions between the nucleus accumbens and the neocortex in humans. Six patients performed a demanding covert visual attention task while we simultaneously recorded brain activity from deep-brain electrodes implanted in the nucleus accumbens and the surface electroencephalogram (EEG). Both theta and alpha oscillations were strongly coherent with the frontal and parietal EEG during the task. Theta-band coherence increased during processing of the visual stimuli. Granger causality analysis revealed that the nucleus accumbens was communicating with the neocortex primarily in the theta-band, while the cortex was communicating the nucleus accumbens in the alpha-band. These data are consistent with a model, in which theta- and alpha-band oscillations serve dissociable roles: Prior to stimulus processing, the cortex might suppress ongoing processing in the nucleus accumbens by modulating alpha-band activity. Subsequently, upon stimulus presentation, theta oscillations might facilitate the active exchange of stimulus information from the nucleus accumbens to the cortex.  相似文献   
54.
We compared the function and composition of free-living and particle-associated microbial communities at an inshore site in coastal North Carolina and across a depth profile on the Blake Ridge (offshore). Hydrolysis rates of six different polysaccharide substrates were compared for particle-associated (>3 μm) and free-living (<3 to 0.2 μm) microbial communities. The 16S rRNA- and rDNA-based clone libraries were produced from the same filters used to measure hydrolysis rates. Particle-associated and free-living communities resembled one another; they also showed similar enzymatic hydrolysis rates and substrate preferences. All six polysaccharides were hydrolyzed inshore. Offshore, only a subset was hydrolyzed in surface water and at depths of 146 and 505 m; just three polysaccharides were hydrolyzed at 505 m. The spectrum of bacterial taxa changed more subtly between inshore and offshore surface waters, but changed greatly with depth offshore. None of the OTUs occurred at all sites: 27 out of the 28 major OTUs defined in this study were found either exclusively in a surface or in a mid-depth/bottom water sample. This distinction was evident with both 16S rRNA and rDNA analyses. At the offshore site, despite the low community overlap, bacterial communities maintained a degree of functional redundancy on the whole bacterial community level with respect to hydrolysis of high-molecular-weight substrates.  相似文献   
55.
In order to investigate the potential role of arctic geese in the epidemiology, the spatial and temporal spread of selected avian diseases, in autumn 2002, a virological and serological survey designed as capture-mark-resighting study was conducted in one of the most important coastal resting sites for migratory waterfowl in Germany. Oropharyngeal, cloacal swabs and blood samples were collected from a total of 147 birds comprising of three different arctic geese species including White-fronted Goose (Anser albifrons), Tundra Bean Goose (Anser fabalis rossicus), Pink-footed Goose (Anser brachyrhynchus) as well as from 29 non-migratory Canada Geese (Branta canadensis). Altogether, six adeno-like viruses (ALV; 95% CI, 1.74?C9.92%) and two avian paramyxoviruses (APMV-4; 95% CI, 0.19?C5.53%) were isolated mainly from juvenile White-fronted Geese. In addition, four Canada Geese were infected with lentogenic APMV-1 (95% CI, 3.89?C31.66%) at the date of sampling. No avian influenza viruses, reo-like viruses could be isolated despite serological evidence. Likewise, no evidence of current or previous infection by West Nile virus was found. Of the 147 birds tagged in the following years, 137 birds were re-sighted between 2002 and 2008 accumulating to 1925 sightings. About 90% of all sightings were reported from the main wintering and resting sites in Germany and The Netherlands. Eight of the resighted geese were virus positive (ALV and APMV-4) at the time point of sampling in 2002.  相似文献   
56.
Cryptic diversity represents a major challenge to the accurate assessment of biodiversity, but the combined use of genetic and morphological analyses has proven to be a powerful approach to detect it. This is especially important for groups for which genetic information is not yet available. Here, we studied the highly conspicuous habitat‐forming Pyura stolonifera species complex (Tunicata), which, as has recently been revealed, shows surprising levels of cryptic diversity, but whose systematics and biogeographical patterns in Australasia nonetheless remain poorly understood. We first present detailed taxonomic information of all the species associated with the P. stolonifera species complex. We then proceed to describe the results of an exhaustive survey that included south‐east Australia, Tasmania, and New Zealand. Subsequently, we present morphological and mitonuclear genetic analysis of two unresolved lineages that comprise the species Pyura praeputialis and a species that is formally described here ( Pyura doppelgangera sp. nov. ). Although the ranges of these two species overlap on mainland Australia, we found no sites at which both species live in sympatry, and there was no morphological or genetic evidence of hybridization. Taken together, the present study illustrates the usefulness of a combined morphogenetic approach in unravelling overlooked marine diversity in a relatively well‐studied region. © 2013 The Linnean Society of London  相似文献   
57.

Recent molecular analyses show that microbial communities of deep marine sediments harbor members of distinct, uncultured bacterial and archaeal lineages, in addition to Gram-positive bacteria and Proteobacteria that are detected by cultivation surveys. Several of these subsurface lineages show cosmopolitan occurrence patterns; they can be found in cold marine sediments and also in hydrothermal habitats, suggesting a continuous deep subsurface and hydrothermal biosphere with shared microbiota. The physiologies and activities of these uncultured subsurface lineages remain to be explored by innovative combinations of genomic and biogeochemical approaches.  相似文献   
58.

Objective

This study aims to describe the virological, immunological and clinical efficacy of protease inhibitor (PI)-based second-line antiretroviral therapy (ART) in rural South Africa.

Methods

An observational cohort study was performed on 210 patients (including 39 children) who initiated PI-based second-line therapy at least 12 months prior to data collection. Biannual clinical, immunological and virological monitoring was performed. Primary endpoints were adequate virological response (plasma HIV-1 RNA<400 copies/ml), full virological suppression (plasma HIV-1 RNA<50 copies/ml) and treatment failure (virological failure (plasma HIV-1 RNA>1000 after initial virological response) or on-going viremia (plasma HIV-1 RNA never<400 copies/ml for more than six months)). Data were analyzed by an on-treatment (OT) and intention-to-treat (ITT) approach. Analyses were primarily performed on the group of patients who switched following first-line virological failure.

Results

Median duration of follow-up after switch to second-line treatment was 20 months [IQR 11–35]. 191 patients had switched to second-line ART due to first-line virological failure. 139/191 of them (72.8%, ITT) were in care and on treatment at the end of follow-up and 11/191 (5.8%, ITT) had died. After twelve months, an adequate virological response was seen in 92/128 patients (71.9%, OT), of which 78/128 (60.9%, OT) experienced full virological suppression. Virological response remained stable after 24 months. Virological efficacy was similar amongst adult and pediatric patients. As in first-line ART, we observed a lack of correlation between virological failure and WHO-defined immunological failure.

Conclusions

Good virological outcomes following first-line failure can be achieved with PI-based, second-line antiretroviral therapy in both adult and pediatric patients in rural South Africa. Retention rates were high and virological outcomes were sustainable during the two-year follow-up period, although persisting low-level viremia occurred in a subset of patients. The observed viro-immunological dissociation emphasizes the need for virological monitoring.  相似文献   
59.
Whole‐room indirect calorimeters have been used to study human metabolism for more than a century. These studies have contributed substantial knowledge to the assessment of nutritional needs and the regulation of energy expenditure and substrate oxidation in humans. However, comparing results from studies conducted at different sites is challenging because of a lack of consistency in reporting technical performance, study design, and results. In May 2019, an expert panel was convened to consider minimal requirements for conducting and reporting the results of human whole‐room indirect calorimeter studies. We propose Room Indirect Calorimetry Operating and Reporting Standards, version 1.0 (RICORS 1.0) to provide guidance to ensure consistency and facilitate meaningful comparisons of human energy metabolism studies across publications, laboratories, and clinical sites.  相似文献   
60.
Airway smooth muscle (ASM) regulation of airway structure and contractility is critical in fetal/neonatal physiology in health and disease. Fetal lungs experience higher Ca2+ environment that may impact extracellular Ca2+ ([Ca2+]o) sensing receptor (CaSR). Well-known in the parathyroid gland, CaSR is also expressed in late embryonic lung mesenchyme. Using cells from 18-22 week human fetal lungs, we tested the hypothesis that CaSR regulates intracellular Ca2+ ([Ca2+]i) in fetal ASM (fASM). Compared with adult ASM, CaSR expression was higher in fASM, while fluorescence Ca2+ imaging showed that [Ca2+]i was more sensitive to altered [Ca2+]o. The fASM [Ca2+]i responses to histamine were also more sensitive to [Ca2+]o (0–2 mM) compared with an adult, enhanced by calcimimetic R568 but blunted by calcilytic NPS2143. [Ca2+]i was enhanced by endogenous CaSR agonist spermine (again higher sensitivity compared with adult). Inhibition of phospholipase C (U73122; siRNA) or inositol 1,4,5-triphosphate receptor (Xestospongin C) blunted [Ca2+]o sensitivity and R568 effects. NPS2143 potentiated U73122 effects. Store-operated Ca2+ entry was potentiated by R568. Traction force microscopy showed responsiveness of fASM cellular contractility to [Ca2+]o and NPS2143. Separately, fASM proliferation showed sensitivity to [Ca2+]o and NPS2143. These results demonstrate functional CaSR in developing ASM that modulates airway contractility and proliferation.  相似文献   
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