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Valero MA Perez-Crespo I Khoubbane M Artigas P Panova M Ortiz P Maco V Espinoza JR Mas-Coma S 《Infection, genetics and evolution》2012,12(2):403-410
Fascioliasis is a zoonotic parasitic disease caused by Fasciola hepatica and Fasciola gigantica. Of both species, F. hepatica is the only one described in the Americas, mainly transmitted by lymnaeid snail vectors of the Galba/Fossaria group. Human fascioliasis endemic areas are mainly located in high altitude areas of Andean countries. Given the necessity to characterize F. hepatica populations involved, the phenotypic features of fasciolid adults infecting sheep present in human fascioliasis endemic areas were analysed in the Cajamarca Valley and Mantaro Valley (valley transmission patterns) and the northern Bolivian Altiplano (altiplanic transmission pattern). A computer image analysis system (CIAS) was applied on the basis of standardized measurements. The aforementioned highland populations were compared to standard lowland natural and experimental populations of European origin. Liver fluke size was studied by multivariate analyses. Two phenotypic patterns could be distinguished in F. hepatica adult size: the valley pattern (Cajamarca and Mantaro, Peru) and the altiplanic pattern (northern Altiplano, Bolivia). Results showed that the Andean valley population and European standard populations presented a phenotypic homogeneity. The Altiplano population showed a large size range with a pronouncedly lower minimum size indicating that uterus gravidity is reached at a smaller size than in valley populations. The results of this study demonstrate that there is no apparent relationship between the shape of fasciolid adults with regard to altitudinal difference or geographical origin and that allometry-free shape appears as a more stable trait than size in fasciolid species. Results are analysed in terms of intensity/crowding effect aspects and permanent/seasonal transmission characteristics. 相似文献
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García AM González-Galarzo MC Ronda E Ballester F Estarlich M Guxens M Lertxundia A Martinez-Argüelles B Marina LS Tardón A Vrijheid M 《International journal of public health》2012,57(5):817-826
Objectives
We describe reported exposures to main categories of occupational agents and conditions in Spanish pregnant workers.Methods
Women were recruited at 12th week of pregnancy from main public gynaecological consults to be included in the INMA Spanish cohorts study (n?=?2,058). Through personal interviews with structured questionnaires, information on working situation and working conditions during pregnancy was obtained.Results
Fifty percent of the women reported frequent exposure to physical load (standing, heavy lifting) and 45?% reported exposure to three or more indicators of job strain. Exposure to at least one physical agent (noise, vibrations, etc.) affected 25?% of the women. Exposure to chemicals was reported by 20?% of the women, mostly including solvents and cleaning products. Eight percent of the women worked at night shifts. Job strain was more prevalent in office workers and industrial operators. Industrial workers showed the highest prevalence of exposure to chemical and physical pollutants.Conclusions
Our data suggest that working conditions of pregnant women may need increased control in Spain. 相似文献994.
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Introini U Casalino G Querques G Gimeno AT Scotti F Bandello F 《Eye (London, England)》2012,26(7):976-982
Purpose
To evaluate changes in macular morphology due to myopic choroidal neovascularization (CNV), using spectral-domain optical coherence tomography (SD-OCT).Methods
In all, 22 eyes with recent-onset untreated CNV underwent 1 intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF), followed by a pro-re-nata regimen. SD-OCT was performed at baseline (before first administration of anti-VEGF treatment) and month 1, and 2; macular morphologic changes and outer retina characteristics (SD-OCT findings) associated with CNV activity were evaluated. Sensitivity and specificity were calculated for SD-OCT findings using fluorescein angiography (FA) as standard reference.Results
Mean central retinal thickness (CRT) showed no significant reduction from baseline (284±98 μm) to month 1 (257±74 μm) and month 2 (263±72 μm). A hyper-reflective lesion with fuzzy borders (fuzzy area), and ‘absent or altered'' IS/OS junction were the only SD-OCT findings associated with CNV activity (P<0.0001). Both these SD-OCT findings showed good sensitivity and specificity (95.1 and 96.0% (95% CI: 0.87–0.89), respectively, for the fuzzy area; 87.9 and 66.7% (95% CI: 0.65–0.87), respectively, for ‘absent or altered'' IS/OS junction) when compared with FA leakage (standard reference).Conclusions
Outer retina characteristics (ie, hyper-reflective lesion with fuzzy borders, and ‘absent or altered'' IS/OS junction) appear more meaningful than CRT in the evaluation of myopic CNV activity. These SD-OCT findings show overall good sensitivity and specificity when compared with FA leakage (standard reference), and could be considered as an alternative diagnostic tool to FA for myopic CNV monitoring. 相似文献1000.