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1.
Small-scale concentration of viruses (sample volumes 1-10 L, here simulated with spiked 100 ml water samples) is an efficient, cost-effective way to identify optimal parameters for virus concentration. Viruses can be concentrated from water using filtration (electropositive, electronegative, glass wool or size exclusion), followed by secondary concentration with beef extract to release viruses from filter surfaces, and finally tertiary concentration resulting in a 5-30 ml volume virus concentrate. In order to identify optimal concentration procedures, two different electropositive filters were evaluated (a glass/cellulose filter [1MDS] and a nano-alumina/glass filter [NanoCeram]), as well as different secondary concentration techniques; the celite technique where three different celite particle sizes were evaluated (fine, medium and large) followed by comparing this technique with that of the established organic flocculation method. Various elution additives were also evaluated for their ability to enhance the release of adenovirus (AdV) particles from filter surfaces. Fine particle celite recovered similar levels of AdV40 and 41 to that of the established organic flocculation method when viral spikes were added during secondary concentration. The glass/cellulose filter recovered higher levels of both, AdV40 and 41, compared to that of a nano-alumina/glass fiber filter. Although not statistically significant, the addition of 0.1% sodium polyphosphate amended beef extract eluant recovered 10% more AdV particles compared to unamended beef extract.  相似文献   
2.
Aging of the population is a growing problem in all developed societies. The older people need more health and social services, and their life quality in there is getting more and more important. The study aimed at determining the characteristics of non-verbal communication of the older people living in old people's homes (OPH). The sample consisted of 267 residents of the OPH, aged 65-96 years, and 267 caregivers from randomly selected twenty-seven OPH. Three types of non-verbal communication were observed and analysed using univariate and multivariate statistical methods. In face expressions and head movements about 75% older people looked at the eyes of their caregivers, and about 60% were looking around, while laughing or pressing the lips together was rarely noticed. The differences between genders were not statistically significant while statistically significant differences among different age groups was observed in dropping the eyes (p = 0.004) and smiling (0.008). In hand gestures and trunk movements, majority of older people most often moved forwards and clenched fingers, while most rarely they stroked and caressed their caregivers. The differences between genders were statistically significant in leaning on the table (p = 0.001), and changing the position on the chair (0.013). Statistically significant differences among age groups were registered in leaning forwards (p = 0.006) and pointing to the others (p = 0.036). In different modes of speaking and paralinguistic signs almost 75% older people spoke normally, about 70% kept silent, while they rarely quarrelled. The differences between genders were not statistically significant while statistically significant differences among age groups was observed in persuasive speaking (p = 0.007). The present study showed that older people in OPH in Slovenia communicated significantly less frequently with hand gestures and trunk movements than with face expressions and head movements or different modes of speaking and paralinguistic signs. The caregivers should be aware of this and pay a lot of attention to these two groups of non-verbal expressions. Their importance should be constantly emphasized during the educational process of all kinds of health-care professionals as well.  相似文献   
3.
The purpose of this paper is to evaluate the incidence of denture repairs in different districts of Croatia through the year of 2002. and to analyse the percentage of different repairs (relinings, simple repairs up to 2 elements and complicated repairs-more than 2 elements) in relation to prosthodontic teams. Data on the number of dentures, and the number and types of denture repairs delivered in the Croatian regions of Zagreb, Rijeka, Split and Karlovac were obtained from the Croatian Institute for Health Insurance for the whole of the year 2002. Information of the number of prosthodontic teams operating in those regions was also obtained. Proportionally more denture repairs were carried out in Karlovac (18%) than Split (5%). The smallest percantage of dentures that required relining was registered in Split and the highest in Rijeka (chi2 = 36.7, p < 0.01). The smallest percentage of simple repairs was registered in Rijeka and the highest in Split (chi2 = 24.3, p < 0.01). The smallest percentage of complicated repairs was registered in Split and the highest in Karlovac. In each region the proportion of denture repairs and types of repairs were correlated with a number of prosthodontic teams in that region. Karlovac had the smallest percentage of specialistic prosthodontic teams and the highest rate of denture repairs.  相似文献   
4.
doi: 10.1111/j.1741‐2358.2011.00592.x
A 3‐year longitudinal study of quality‐of‐life outcomes of elderly patients with implant‐ and tooth‐supported fixed partial dentures in posterior dental regions Background: Clinical studies have mainly been focused on oral health‐related quality‐of‐life (OHRQoL) outcomes of removable dentures. Objective: To evaluate therapy of elderly patients with implant‐supported fixed partial dentures (IFPD) and tooth‐supported fixed partial dentures (FPD) in the posterior dental regions. Patients and methods: The OHIP49 was used to measure OHRQoL in 64 patients with IFPD and 38 patients with FPD, before, 3 weeks and 3 years after rehabilitation. A control group (CG) consisted of 62 individuals. Results: The Oral Health Impact Profile questionnaire (OHIP) follow‐up scores of the patients with FPD and the patients with IFPD were significantly smaller in comparison with the baseline scores (p < 0.01). The OHIP scores were further reduced at the 3‐year follow‐up. The patients with IFPD had significantly higher scores than the patients with FPD and the CG at the baseline and at the follow‐ups. In the patients with FPD, both age groups (≤60 and >60) showed equal improvement of the OHRQoL. In the IFPD group, patients older than 60 years showed better improvement (p < 0.05). There were no significant differences dependent on gender and antagonistic teeth (p > 0.05). Conclusion: The FPD and the IFPD treatment showed significant improvement of OHRQoL. The FPD treatment improved OHRQoL equally in both age groups, while the IFPD treatment improved OHRQoL better in older patients.  相似文献   
5.
Bone (or body) morphogenetic proteins (BMPs) belong to the TGFβ superfamily and are crucial for embryonic patterning and organogenesis as well as for adult tissue homeostasis and repair. Activation of BMP receptors by their ligands leads to induction of several signaling cascades. Using fluorescence recovery after photobleaching, FRET, and single particle tracking microscopy, we demonstrate that BMP receptor type I and II (BMPRI and BMPRII) have distinct lateral mobility properties within the plasma membrane, which is mandatory for their involvement in different signaling pathways. Before ligand binding, BMPRI and a subpopulation of BMPRII exhibit confined motion, reflecting preassembled heteromeric receptor complexes. A second free diffusing BMPRII population only becomes restricted after ligand addition. This paper visualizes time-resolved BMP receptor complex formation and demonstrates that the lateral mobility of BMPRI has a major impact in stabilizing heteromeric BMPRI-BMPRII receptor complexes to differentially stimulate SMAD versus non-SMAD signaling.  相似文献   
6.
Enterococci in the Environment   总被引:3,自引:0,他引:3  
Summary: Enterococci are common, commensal members of gut communities in mammals and birds, yet they are also opportunistic pathogens that cause millions of human and animal infections annually. Because they are shed in human and animal feces, are readily culturable, and predict human health risks from exposure to polluted recreational waters, they are used as surrogates for waterborne pathogens and as fecal indicator bacteria (FIB) in research and in water quality testing throughout the world. Evidence from several decades of research demonstrates, however, that enterococci may be present in high densities in the absence of obvious fecal sources and that environmental reservoirs of these FIB are important sources and sinks, with the potential to impact water quality. This review focuses on the distribution and microbial ecology of enterococci in environmental (secondary) habitats, including the effect of environmental stressors; an outline of their known and apparent sources, sinks, and fluxes; and an overview of the use of enterococci as FIB. Finally, the significance of emerging methodologies, such as microbial source tracking (MST) and empirical predictive models, as tools in water quality monitoring is addressed. The mounting evidence for widespread extraenteric sources and reservoirs of enterococci demonstrates the versatility of the genus Enterococcus and argues for the necessity of a better understanding of their ecology in natural environments, as well as their roles as opportunistic pathogens and indicators of human pathogens.  相似文献   
7.
Cardiac cushion formation is crucial for both valvular and septal development. Disruption in this process can lead to valvular and septal malformations, which constitute the largest part of congenital heart defects. One of the signaling pathways that is important for cushion formation is the TGFβ superfamily. The involvement of TGFβ and BMP signaling pathways in cardiac cushion formation has been intensively studied using chicken in vitro explant assays and in genetically modified mice. In this review, we will summarize and discuss the role of TGFβ and BMP signaling components in cardiac cushion formation.  相似文献   
8.
To constitute a valuable resource to identify individual genes involved in the development of obesity, a novel mouse model, the Berlin Fat Mouse Inbred line 860 (BFMI860), was established. In order to characterize energy intake and energy expenditure in obese BFMI860 mice, we performed two independent sets of experiments in male BFMI860 and B6 control mice (10 per line). In experiment 1, we analyzed body fat content noninvasively by dual‐energy X‐ray absorptiometry and measured resting metabolic rate at thermoneutrality (RMRt) and respiratory quotient (RQ) in week 6, 10, and 18. In a second experiment, energy digested (energy intake minus fecal energy loss) was determined by bomb calorimetry from week 6 through week 12. BFMI860 mice were heavier and had higher fat mass (final body fat content was 24.7% compared with 14.6% in B6). They also showed fatty liver syndrome. High body fat accumulation in BFMI860 mice was restricted to weeks 6–10 and was accompanied by hyperphagia, higher energy digestion, higher RQs, and abnormally high blood triglyceride levels. Lean mass–adjusted RMRt was not altered between lines. These results indicate that in BFMI860 mice, the excessive accumulation of body fat is associated with altered lipid metabolism, high energy intake, and energy digestion. Assuming that BFMI860 mice and their obese phenotypes are of polygenic nature, this line is an excellent model for the study of obesity in humans, especially for juvenile obesity and hyperlipidemia.  相似文献   
9.
The sanitary quality of recreational waters that may be impacted by sewage is assessed by enumerating fecal indicator bacteria (FIB) (Escherichia coli and enterococci); these organisms are found in the gastrointestinal tracts of humans and many other animals, and hence their presence provides no information about the pollution source. Microbial source tracking (MST) methods can discriminate between different pollution sources, providing critical information to water quality managers, but relatively little is known about factors influencing the decay of FIB and MST genetic markers following release into aquatic environments. An in situ mesocosm was deployed at a temperate recreational beach in the Mississippi River to evaluate the effects of ambient sunlight and biotic interactions (predation, competition, and viral lysis) on the decay of culture-based FIB, as well as molecularly based FIB (Entero1a and GenBac3) and human-associated MST genetic markers (HF183 and HumM2) measured by quantitative real-time PCR (qPCR). In general, culturable FIB decayed the fastest, while molecularly based FIB and human-associated genetic markers decayed more slowly. There was a strong correlation between the decay of molecularly based FIB and that of human-associated genetic markers (r2, 0.96 to 0.98; P < 0.0001) but not between culturable FIB and any qPCR measurement. Overall, exposure to ambient sunlight may be an important factor in the early-stage decay dynamics but generally was not after continued exposure (i.e., after 120 h), when biotic interactions tended to be the only/major influential determinant of persistence.  相似文献   
10.
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