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11.
12.
Urbanus AT van den Hoek A Boonstra A van Houdt R de Bruijn LJ Heijman T Coutinho RA Prins M 《PloS one》2011,6(9):e24736
Background
Although published results are inconsistent, it has been suggested that tattooing and piercing are risk factors for HBV and HCV infections. To examine whether tattooing and piercing do indeed increase the risk of infection, we conducted a study among people with multiple tattoos and/or piercings in the Netherlands who acquired their tattoos and piercings in the Netherlands and/or abroad.Methods
Tattoo artists, piercers, and people with multiple tattoos and/or piercings were recruited at tattoo conventions, shops (N = 182), and a biannual survey at our STI-outpatient clinic (N = 252) in Amsterdam. Participants were interviewed and tested for anti-HBc and anti-HCV. Determinants of HBV and HCV infections were analysed using logistic regression analysis.Results
The median number of tattoos and piercings was 5 (IQR 2–10) and 2 (IQR 2–4), respectively. Almost 40% acquired their tattoo of piercing abroad. In total, 18/434 (4.2%, 95%CI: 2.64%–6.46%) participants were anti-HBc positive and 1 was anti-HCV positive (0.2%, 95%CI: 0.01%–1.29%). Being anti-HBc positive was independently associated with older age (OR 1.68, 95%CI: 1.03–2.75 per 10 years older) and being born in an HBV-endemic country (OR 7.39, 95%CI: 2.77–19.7). Tattoo- and/or piercing-related variables, like having a tattoo or piercing in an HBV endemic country, surface percentage tattooed, number of tattoos and piercings etc., were not associated with either HBV or HCV.Conclusions
We found no evidence for an increased HBV/HCV seroprevalence among persons with multiple tattoos and/or piercings, which might be due to the introduction of hygiene guidelines for tattoo and piercing shops in combination with the low observed prevalence of HBV/HCV in the general population. Tattoos and/or piercings, therefore, should not be considered risk factors for HBV/HCV in the Dutch population. These findings imply the importance of implementation of hygiene guidelines in other countries. 相似文献13.
Resource partitioning between sympatric wild and domestic herbivores in the Tarangire region of Tanzania 总被引:5,自引:1,他引:5
The effect of the introduction of an exotic species (cattle) into a native African herbivore assemblage was investigated
by studying resource partitioning between zebu cattle, wildebeest and zebra. Resource partitioning was investigated by analysing
grass sward characteristics (such as sward height and percentage nitrogen in leaves) of feeding sites selected by the different
herbivore species. Linear discriminant analysis was used to determine whether a distinction could be made between feeding
sites selected by the different animal species or whether the animal species showed overlap in resource use by selecting similar
feeding sites. Wildebeest and zebra did not show overlap in resource use except in the wet season when resources were ample.
Cattle showed overlap in resource use with zebra in the early wet season and with wildebeest in the early dry season, seasons
when food limitation is likely. In the wet season, cattle showed overlap in resource use with both zebra and wildebeest.
Implications of these results for competitive relationships between livestock and wildlife are discussed. We suggest that
interpretation of overlap in resource use may be different for an assemblage of long-term coexisting native species as compared
to an assemblage of native and exotic species. Among native herbivores, overlap in resource use is not expected based on evolutionary
segregation. In a native assemblage to which an exotic species has been introduced, however, overlap in resource use can occur
under food-limited conditions and consequently implies competition.
Received: 1 September 1998 / Accepted: 20 April 1999 相似文献
14.
Guofeng Wu Jan de Leeuw Andrew K. Skidmore Herbert H. T. Prins Elly P. H. Best Yaolin Liu 《Hydrobiologia》2009,623(1):213-222
Almost 95% of the entire population of the Siberian crane (Grus leucogeranus) winter in Poyang Lake, China, where they forage on the tubers of the submerged aquatic macrophyte Vallisneria spiralis. The Three Gorges Dam on the Yangtze River may possibly affect this food source of the Siberian crane by affecting the light
intensity reaching the top of the V. spiralis canopy. In this study, the photosynthetically active radiation at the top of the V. spiralis canopy (PARtc) in Lake Dahuchi was modeled from 1998 to 2006, and the potential impacts of changes in water level and turbidity on the
underwater light climate of V. spiralis were analyzed. PARtc was calculated from incident irradiance while the losses due to reflection at the water surface, absorption, and scattering
within the water column were taken into consideration. The results indicated significant differences in PARtc between years. Six years of water level and Secchi disk depth records revealed a seasonal switching of the lake from a turbid
state at low water levels in autumn, winter, and spring to a clear state at high water levels during the monsoon in summer.
The highest PARtc occurred at intermediate water levels, which were reached when the Yangtze River forces Lake Dahuchi out of its turbid state
in early summer and the water becomes clear. The intended operation of the Three Gorges Dam, which will increase water levels
in May and June, may advance the moment when Lake Dahuchi switches from turbid to clear. We suggest that this might increase
production of V. spiralis and possibly improve the food habitat conditions for wintering Siberian crane in Poyang Lake.
相似文献
Guofeng WuEmail: |
15.
16.
STIM1 is an endoplasmic reticulum (ER) membrane Ca(2+) sensor responsible for activation of store-operated Ca(2+) influx. We discovered that STIM1 oligomerization and store-operated Ca(2+) entry (SOC) are modulated by the ER oxidoreductase ERp57. ERp57 interacts with the ER luminal domain of STIM1, with this interaction involving two conserved cysteine residues, C(49) and C(56). SOC is accelerated in the absence of ERp57 and inhibited in C(49) and C(56) mutants of STIM1. We show that ERp57, by ER luminal interaction with STIM1, has a modulatory role in capacitative Ca(2+) entry. This is the first demonstration of a protein involved in ER intraluminal regulation of STIM1. 相似文献
17.
Ilse J. E. Flink Rick G. Prins Johan J. P. Mackenbach Vincent W. Jaddoe Albert Hofman Frank C. Verhulst Henning Tiemeier Hein Raat 《PloS one》2013,8(8)
Background
Studies suggest that neighborhood ethnic diversity may be important when it comes to understanding ethnic inequalities in mental health. The primary aim of this study was to investigate whether neighborhood ethnic diversity moderated the association between the ethnic minority status and child behavioral and emotional problems.Methods
We included 3076 preschoolers participating in the Generation R Study, a birth cohort study in Rotterdam, the Netherlands. At child age 3-years, parents completed the Child Behavior Checklist (CBCL/1,5-5). Individual-level data, assessed with questionnaires, was combined with neighborhood-level data. Multi-level logistic regression models predicted the Odds Ratios for the CBCL total problems score as a function of maternal ethnic background and neighborhood ethnic diversity, computed with the Racial Diversity Index and categorized into tertiles. Interaction on the additive scale was assessed using Relative Access Risk due to Interaction.Results
Being from an ethnic minority was associated with child behavioral and emotional problems in unadjusted (OR 2.76, 95% CI 1.88–4.04) and adjusted models (OR 2.64, 95% CI 1.79–3.92). Residing in a high diversity neighborhood was associated with child behavioral and emotional problems in unadjusted (OR 2.03, 95% CI 1.13–3.64) but not in adjusted models (OR 0.89, 95% CI 0.51–1.57). When stratifying by the three levels of neighborhood ethnic diversity, ethnic inequalities in behavioral and emotional problems were greatest in low diversity neighborhoods (OR 5.24, 95%CI 2.47–11.14), smaller in high diversity neighborhoods (OR 3.15, 95% CI 1.66–5.99) and smallest in medium diversity neighborhoods (OR 1.59, 95% CI 0.90–2.82). Tests for interaction (when comparing medium to low diversity neighborhoods) trended towards negative on both the additive and multiplicative scale for the maternal-report (RERI: −3.22, 95% CI −0.70–0.59; Ratio of ORs: 0.30, 95% CI 0.12–0.76).Conclusion
This study suggests that ethnic inequalities in child behavioral and emotional problems may be greatest in ethnically homogeneous neighborhoods. 相似文献18.
19.
Interrelations between sulfate-reducing and methane-producing bacteria in bottom deposits of a fresh-water lake. III. Experiments with 14C-labeled substrates 总被引:31,自引:0,他引:31
An ecological substrate relationship between sulfate-reducing and methane-producing bacteria in mud of Lake Vechten has been studied in experiments using 14C-labeled acetate and lactate as substrates. Fluoroacetate strongly inhibited the formation of 14CO2 from [U-14C]-acetate and β-fluorolactate gave an inhibition of similar magnitude of the breakdown of [U-14C]-l-lactate to 14CO2 thus confirming earlier results on the specific action of these inhibitors. The turnover-rate constant of l-lactate was 2.37 hr-1 and the average l-lactate pool size was 12.2 μg per gram of wet mud, giving a turnover rate of 28.9 μg of lactate/gram of mud per hr. The turnover-rate constant of acetate was 0.35 hr-1 and the average pool size was 5.7 μg per gram of wet mud, giving a rate of disappearance of 1.99 μg of acetate/gram of mud per hr. Estimations of the acetate turnover rate based upon the formation of 14CO2 from [U-14C]-acetate or [1-14C]-acetate yielded figures of the same magnitude (range 0.45 to 1.74). These and other results suggest that only a portion of the lactate dissimilated is turned over through the acetate pool. The ratio of 14CO2/14CH4 produced from [U-14C]-acetate by mud was 1.32; indicating that 0.862 moles of CH4 and 1.138 moles of CO2 are formed per mole of acetate. From the rate of disappearance of acetate (0.027 μmoles/gram wet mud per hr) and the rate of methane production (0.034 μmoles/gram wet mud per hr), it may be concluded that acetate is an important precursor of methanogenesis in mud (approximately 70%). A substrate relationship between the two groups of bacteria is likely since 14CH4 was formed from [U-14C]-l-lactate. 相似文献
20.
Frans A. Prins Ronnie van Diemen-Steenvoorde Jan Bonnet Ingrid Cornelese-ten Velde 《Histochemistry and cell biology》1993,99(6):417-425
Reflection contrast microscopy (RCM) of ultrathin sections was recently introduced as a sensitive technique for visualization with enhanced definition in immunogold histochemistry. Experience of using RCM as a major tool in immunocytochemical research in different fields is summarized, e.g. oncology, nephrology and embryology. The sensitive visualization of immunocytochemical labels, gold particles or peroxidase-diaminobenzidine deposits in or on ultrathin sections, by RCM instead of electron microscopy is demonstrated. RCM of ultrathin sections is an adequate light microscopical alternative for immunoelectron microscopy, since an overview of both label and tissue is obtained with a high image definition and high contrast of label. In the studies presented, RCM is shown to provide a better gradation in staining intensity and staining pattern than other light microscopical methods. Moreover, a precise localization of multiple labels is obtained with this method. Besides the applications shown, ultrathin section visualization by RCM is very useful for correlative light- and electron microscopical studies of fine structures. Commercially available fluorescence microscopes can be adapted for proper RCM functioning; an adaptation scheme and list of microscopes tested is provided. 相似文献