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21.
Manuel Calvopi?a William Cevallos Richard Atherton Matthew Saunders Alexander Small Hideo Kumazawa Hiromu Sugiyama 《PLoS neglected tropical diseases》2015,9(2)
Background
Amphimerus sp. is a liver fluke which recently has been shown to have a high prevalence of infection among an indigenous group, Chachi, who reside in a tropical rainforest in the northwestern region of Ecuador. Since it is unknown which animals can act as a reservoir and/or definitive hosts for Amphimerus sp. in this endemic area, a study was done to determine the prevalence of infection in domestic cats and dogs. This information is important to understand the epidemiology, life cycle and control of this parasite.Methodology/Findings
In July 2012, three Chachi communities located on Rio Cayapas, province of Esmeraldas, were surveyed. A total of 89 of the 109 registered households participated in the study. Of the 27 cats and 43 dogs found residing in the communities, stool samples were collected from 14 cats and 31 dogs (total of 45 animals) and examined microscopically for the presence of Amphimerus eggs. The prevalence of infection was 71.4% in cats and 38.7% in dogs, with similar rates of infection in all three communities. Significantly more cats were infected than dogs (p = 0.042).Conclusions/Significance
The data show a high rate of Amphimerus sp. infection in domestic cats and dogs residing in Chachi communities. It can be concluded that these animals act as definitive and reservoir hosts for this liver fluke and that amphimeriasis is a zoonotic disease. These findings provide important epidemiological data which will aid in the development and implementation of control strategies against the transmission of Amphimerus. 相似文献22.
Alain Dubreuil Steven B. Young John Atherton Thomas P. Gloria 《The International Journal of Life Cycle Assessment》2010,15(6):621-634
Goal, scope, and background
The aim of this work is to present guidance on the application of ISO 14044 to allocation procedures for metal recycling. As such, graphical patterns of metal recycling and generic “rules” for metal recycling maps are presented. The results are intended to be useful in assessing and validating the suitability of allocation procedures for metal recycling in the context of life cycle assessment (LCA) and assist in the understanding of metals flow patterns in product systems. LCA uses a product-focus; therefore, the perspective here is on recycling metals in post-consumer products. The discussions, analysis, and illustrations in this paper emphasize old (post-consumer) scrap and do not detail flows of new (post-manufacturing, pre-consumer) or prompt (internal) scrap. The work included participation and review from International Council on Mining and Metals, the Nickel Institute, the International Copper Association, the International Zinc Association, worldsteel (formerly International Iron and Steel Institute), and the International Aluminium Institute. 相似文献23.
Charlie Strange Felix JF Herth Kevin L Kovitz Geoffrey McLennan Armin Ernst Jonathan Goldin Marc Noppen Gerard J Criner Frank C Sciurba 《BMC pulmonary medicine》2007,7(1):1-12
Background
Lung volume reduction surgery is effective at improving lung function, quality of life, and mortality in carefully selected individuals with advanced emphysema. Recently, less invasive bronchoscopic approaches have been designed to utilize these principles while avoiding the associated perioperative risks. The Endobronchial Valve for Emphysema PalliatioN Trial (VENT) posits that occlusion of a single pulmonary lobe through bronchoscopically placed Zephyr® endobronchial valves will effect significant improvements in lung function and exercise tolerance with an acceptable risk profile in advanced emphysema.Methods
The trial design posted on Clinical trials.gov, on August 10, 2005 proposed an enrollment of 270 subjects. Inclusion criteria included: diagnosis of emphysema with forced expiratory volume in one second (FEV1) < 45% of predicted, hyperinflation (total lung capacity measured by body plethysmography > 100%; residual volume > 150% predicted), and heterogeneous emphysema defined using a quantitative chest computed tomography algorithm. Following standardized pulmonary rehabilitation, patients were randomized 2:1 to receive unilateral lobar placement of endobronchial valves plus optimal medical management or optimal medical management alone. The co-primary endpoint was the mean percent change in FEV1 and six minute walk distance at 180 days. Secondary end-points included mean percent change in St. George's Respiratory Questionnaire score and the mean absolute changes in the maximal work load measured by cycle ergometry, dyspnea (mMRC) score, and total oxygen use per day. Per patient response rates in clinically significant improvement/maintenance of FEV1 and six minute walk distance and technical success rates of valve placement were recorded. Apriori response predictors based on quantitative CT and lung physiology were defined.Conclusion
If endobronchial valves improve FEV1 and health status with an acceptable safety profile in advanced emphysema, they would offer a novel intervention for this progressive and debilitating disease.Trial Registration
ClinicalTrials.gov: NCT00129584 相似文献24.
Carol Saunders Laurie Smith Flemming Wibrand Kirstine Ravn Peter Bross Isabelle Thiffault Mette Christensen Andrea Atherton Emily Farrow Neil Miller Stephen?F. Kingsmore Elsebet Ostergaard 《American journal of human genetics》2015,96(2):258-265
3-methylglutaconic aciduria (3-MGA-uria) is a nonspecific finding associated with mitochondrial dysfunction, including defects of oxidative phosphorylation. 3-MGA-uria is classified into five groups, of which one, type IV, is genetically heterogeneous. Here we report five children with a form of type IV 3-MGA-uria characterized by cataracts, severe psychomotor regression during febrile episodes, epilepsy, neutropenia with frequent infections, and death in early childhood. Four of the individuals were of Greenlandic descent, and one was North American, of Northern European and Asian descent. Through a combination of homozygosity mapping in the Greenlandic individuals and exome sequencing in the North American, we identified biallelic variants in the caseinolytic peptidase B homolog (CLPB). The causative variants included one missense variant, c.803C>T (p.Thr268Met), and two nonsense variants, c.961A>T (p.Lys321∗) and c.1249C>T (p.Arg417∗). The level of CLPB protein was markedly decreased in fibroblasts and liver of affected individuals. CLPB is proposed to function as a mitochondrial chaperone involved in disaggregation of misfolded proteins, resulting from stress such as heat denaturation. 相似文献
25.
Alzheimer''s disease (AD) is pathologically characterised by the age-dependent deposition of β-amyloid (Aβ) in senile plaques, intraneuronal accumulation of tau as neurofibrillary tangles, synaptic dysfunction and neuronal death. Neuroinflammation, typified by the accumulation of activated microglia and reactive astrocytes, is believed to modulate the development and/or progression of AD. We have used primary rat neuronal, astrocytic and mixed cortical cultures to investigate the contribution of astrocyte-mediated inflammatory responses during Aβ-induced neuronal loss. We report that the presence of small numbers of astrocytes exacerbate Aβ-induced neuronal death, caspase-3 activation and the production of caspase-3-cleaved tau. Furthermore, we show that astrocytes are essential for the Aβ-induced tau phosphorylation observed in primary neurons. The release of soluble inflammatory factor(s) from astrocytes accompanies these events, and inhibition of astrocyte activation with the anti-inflammatory agent, minocycline, reduces astrocytic inflammatory responses and the associated neuronal loss. Aβ-induced increases in caspase-3 activation and the production of caspase-3-truncated tau species in neurons were reduced when the astrocytic response was attenuated with minocycline. Taken together, these results show that astrocytes are important mediators of the neurotoxic events downstream of elevated Aβ in models of AD, and suggest that mechanisms underlying pro-inflammatory cytokine release might be an important target for therapy. 相似文献
26.
Liliane?VenturaEmail author Gabriel?Torres?de Jesus Gunter?Camilo Dablas?de Oliveira Sidney?JF?Sousa 《Biomedical engineering online》2005,4(1):70
Background
The authors have developed a small portable device for the objective measurement of the transparency of corneas stored in preservative medium, for use by eye banks in evaluation prior to transplantation. 相似文献27.
Previous fluorescence resonance energy transfer (FRET) measurements, using BIDS (4-benzamido-4'-isothiocyanostilbene-2,2'-disulfonate) as a label for the disulfonic stilbene site and FM (fluorescein-5-maleimide) as a label for the cytoplasmic SH groups on band 3 (AE1), combined with data showing that the cytoplasmic SH groups lie about 40 A from the cytoplasmic surface of the lipid bilayer, would place the BIDS sites very near the membrane's inner surface, a location that seems to be inconsistent with current models of AE1 structure and mechanism. We reinvestigated the BIDS-FM distance, using laser single photon counting techniques as well as steady-state fluorescence of AE1, in its native membrane environment. Both techniques agree that there is very little energy transfer from BIDS to FM. The mean energy transfer (E), based on three-exponential fits to the fluorescence decay data, is 2.5 +/- 0.7% (SEM, N = 12). Steady-state fluorescence measurements also indicate <3% energy transfer from BIDS to FM. These data indicate that the BIDS sites are probably over 63 A from the cytoplasmic SH groups, placing them near the middle or the external half of the lipid bilayer. This relocation of the BIDS sites fits with other evidence that the disulfonic stilbene sites are located farther toward the external membrane surface than Glu-681, a residue near the inner membrane surface whose modification affects the pH dependence and anion selectivity of band 3. The involvement of two relatively distant parts of the AE1 protein in transport function suggests that the transport mechanism requires coordinated large-scale conformational changes in the band 3 protein. 相似文献
28.
Thomas Gloria Andrea Russell John Atherton Scott Baker Murray Cook 《The International Journal of Life Cycle Assessment》2006,11(1):26-33
Goal, Scope and Background The Apeldoorn Workshop (April 15th, 2004, Apeldoorn, NL) brought together specialists in LCA and Risk Assessment to discuss
current practices and complications of the life cycle impact assessment (LCIA) ecological toxicity (ecotox) methodologies
for metals. The consensus was that the LCIA methods currently available do not appropriately characterize impacts of metals
due to lack of fundamental metals chemistry in the models. A review of five methods available to perform ecotox impact assessment
for metals has been prepared to provide Life Cycle Assessment (LCA) practitioners with a better understanding of the current
state of the science and potential biases related to metals. The intent is to provide awareness on issues related to ecotox
impact assessment.
Methods In this paper two case studies, one a copper based product (copper tube), the other a zinc-based product (gutter systems),
were selected and examined by applying freshwater ecological toxicity impact models – USES-LCA, Eco-indicator 99 (EI 99),
IMPACT 2002, EDIP 97, and CalTOX-ETP. Both studies are recent, comprehensive, cradle-to-gate, and peer-reviewed. The objective
is to review the LCIA results in the context of the practical concerns identified by the Apeldoorn Declaration, in particular
illustrating any inconsistencies such as chemical characterization coverage, species specificity, and relative contribution
to impact results.
Results and Discussion The results obtained from all five of the LCIA methods for the copper tube LCI pointed to the same substance as being the
most important – copper. This result was obtained despite major fundamental differences between the LCIA methods applied.
However, variations of results were found when examining the freshwater ecological toxicity potential of zinc gutter systems.
Procedural difficulties and inconsistencies were observed. In part this was due to basic differences in model nomenclature
and differences in coverage (IMPACT 2002+ and EDIP 97 contained characterization factors for aluminium that resulted in 90%
and 22% contribution to burden respectively, the other three methods did not). Differences were also observed relative to
the emissions source compartment. In the case of zinc, air emissions were found to be substantial for some ecotox models,
whereas, water emissions results were found to be of issue for others.
Conclusions This investigation illustrates the need to proceed with caution when applying LCIA ecotox methodologies to life cycle studies
that include metals. Until further improvements are made, the deficiencies should be clearly communicated as part of LCIA
reporting. Business or policy decisions should not without further discussion be based solely on the results of the currently
available methods for assessing ecotoxicity in LCIA.
Outlook The outlook to remedy deficiencies in the ecological toxicity methods is promising. Recently, the LCIA Toxic Impacts Task
Force of the UNEP/SETAC Life Cycle Initiative has formed a subgroup to address specific issues and guide the work towards
establishment of sound characterization factors for metals. Although some measure of precision of estimation of potential
impact has been observed, such as in the case of copper, accuracy is also a major concern and should be addressed. Further
investigation through controlled experimentation is needed, particularly LCIs composed of a variety of inorganics as well
as organics constituents. Support for this activity has come from the scientific community and industry as well. Broader aspects
of structure and nomenclature are being collectively addressed by the UNEP/SETAC Life Cycle Initiative. These efforts will
bring practical solutions to issues of naming conventions and LCI to LCIA flow assignments. 相似文献
29.
RP Tucker K Drabikowski JF Hess J Ferralli R Chiquet-Ehrismann JC Adams 《BMC evolutionary biology》2006,6(1):60-17
Background
Tenascins are a family of glycoproteins found primarily in the extracellular matrix of embryos where they help to regulate cell proliferation, adhesion and migration. In order to learn more about their origins and relationships to each other, as well as to clarify the nomenclature used to describe them, the tenascin genes of the urochordate Ciona intestinalis, the pufferfish Tetraodon nigroviridis and Takifugu rubripes and the frog Xenopus tropicalis were identified and their gene organization and predicted protein products compared with the previously characterized tenascins of amniotes. 相似文献30.