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901.
Anjana Silva Jiri Hlusicka Nipuna Siribaddana Subodha Waiddyanatha Senaka Pilapitiya Prasanna Weerawansa Niroshan Lokunarangoda Sujeewa Thalgaspitiya Sisira Siribaddana Geoffrey K. Isbister 《PLoS neglected tropical diseases》2020,14(11)
Delays in treatment seeking and antivenom administration remain problematic for snake envenoming. We aimed to describe the treatment seeking pattern and delays in admission to hospital and administration of antivenom in a cohort of authenticated snakebite patients. Adults (> 16 years), who presented with a confirmed snakebite from August 2013 to October 2014 were recruited from Anuradhapura Hospital. Demographic data, information on the circumstances of the bite, first aid, health-seeking behaviour, hospital admission, clinical features, outcomes and antivenom treatment were documented prospectively. There were 742 snakebite patients [median age: 40 years (IQR:27–51; males: 476 (64%)]. One hundred and five (14%) patients intentionally delayed treatment by a median of 45min (IQR:20-120min). Antivenom was administered a median of 230min (IQR:180–360min) post-bite, which didn’t differ between directly admitted and transferred patients; 21 (8%) receiving antivenom within 2h and 141 (55%) within 4h of the bite. However, transferred patients received antivenom sooner after admission to Anuradhapura hospital than those directly admitted (60min [IQR:30-120min] versus 120min [IQR:52-265min; p<0.0001]). A significantly greater proportion of transferred patients had features of systemic envenoming on admission compared to those directly admitted (166/212 [78%] versus 5/43 [12%]; p<0.0001), and had positive clotting tests on admission (123/212 [58%] versus 10/43 [23%]; p<0.0001). Sri Lankan snakebite patients present early to hospital, but there remains a delay until antivenom administration. This delay reflects a delay in the appearance of observable or measurable features of envenoming and a lack of reliable early diagnostic tests. Improved early antivenom treatment will require reliable, rapid diagnostics for systemic envenoming. 相似文献
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903.
Abstract O6-(4-Nitrophenyl)inosine (la), O6 -(4-nitrophenyl)guanosine (1c) and O6 -(4-methylumbelliferonyl)inosine (2) were obtained by reaction of 6-chloro-9-(β-D-ribofuranosyl)purine (3a) or 2-amino-6-chloro-9-(β-D-ribofuranosyl)purine (3c) with sodium salts of 4-nitrophenol or 4-methylumbelliferone in N,N-dimethylformamide. Similarly, 6-chloro-9-(β-D-2,3-isopropylideneribofuranosyl)purine (3b) was transformed to 2′,3′-O-isopropylidene-O6-(4-nitrophenyl)inosine (1b). Deprotection of 1b with CF3COOH gave compound la and O6 -(4-nitrophenyl)hypoxanthine (4). Compounds 1a and 1c are substrates for adenosine deaminase releasing 4-nitrophenol which is readily detected visually or spectrophotomemcally. Rate and extent of hydrolysis of la are significantly increased in the presence of purine nucleoside phosphorylase but xanthine oxidase has no influence. A potential fluorogenic analogue 2 is not a substrate for adenosine deaminase. 相似文献
904.
905.
906.
Martin Konvicka Jiri Benes Oldrich Cizek Frantisek Kopecek Ondrej Konvicka Lubomir Vitaz 《Journal of Insect Conservation》2008,12(5):519-525
We describe a rapid extirpation of a strong population of globally threatened butterfly, Colias myrmidone, from the White Carpathians, Czech Republic. The area is renowned for a high plant and insect diversity associated with savannah-like
Carpathian meadows, traditionally managed by mowing once a year and subsequent autumn grazing. Although many meadows fell
victim to land consolidation schemes in the 1970s and 1980s, over 2000 hectares have been preserved in a dense network of
reserves. The reserve management practised since the mid-1990s has consisted of uniform machine mowing of entire areas and
this was further accelerated after accession of the Czech Republic to the EU, when agri-environmental schemes (AES) required
two cuts per year. This starkly conflicted with the life history of C. myrmidone, because both spring and autumn cuts interfere with larval development. Despite intensive surveys, only five and then two
C. myrmidone individuals were seen in the area in 2005 and 2006, respectively, rendering the species effectively extinct. Conservation
authorities failed by neglecting early warning signals issued by amateur entomologists, and by ignoring the basic tenets of
conservation of insect diversity, such as the need to maintain heterogeneity of resources. Unless AES provide for this crucial
aspect of habitat suitability for invertebrates, they may turn from a great hope into a massive failure. 相似文献
907.
The removal of toluene and xylene from an artificial waste gaswas investigated in two laboratory scale biofilters filled withmixtures of peat, bark and wood. The packed beds differed in themixture of materials used, so that peat and then bark was thedominant constituent. The biofilters were operated in an upflowmode. Both biofilters showed relatively high removal efficienciesfor both pollutants (74–98%). The evaluation of the localelimination capacities in the peat-loaded biofilter revealed thatthe major part of pollutants was degraded in the middle layer.In this biofilter, larger differences in theremoval rates along the bed height were also observed. In thebiofilter with bark as dominant material, the major part ofpollutants was degraded at the inlet of the bed and also at arelative height of 0.7. Moisture contents of 71–80% and 65–78%were found for the biofilter with peat and bark respectively. Whenthe regular pouring of nutrient solution through the bed wasinterrupted for 1 month, a decrease in efficiency was observed inthe biofilter with bark, whilst the efficiency in the biofilter withpeat remained the same. 相似文献
908.
Tomas Wald Adriana Osickova Miroslav Sulc Oldrich Benada Alena Semeradtova Lenka Rezabkova Vaclav Veverka Lucie Bednarova Jan Maly Pavel Macek Peter Sebo Ivan Slaby Jiri Vondrasek Radim Osicka 《The Journal of biological chemistry》2013,288(31):22333-22345
Tooth enamel, the hardest tissue in the body, is formed by the evolutionarily highly conserved biomineralization process that is controlled by extracellular matrix proteins. The intrinsically disordered matrix protein ameloblastin (AMBN) is the most abundant nonamelogenin protein of the developing enamel and a key element for correct enamel formation. AMBN was suggested to be a cell adhesion molecule that regulates proliferation and differentiation of ameloblasts. Nevertheless, detailed structural and functional studies on AMBN have been substantially limited by the paucity of the purified nondegraded protein. With this study, we have developed a procedure for production of a highly purified form of recombinant human AMBN in quantities that allowed its structural characterization. Using size exclusion chromatography, analytical ultracentrifugation, transmission electron, and atomic force microscopy techniques, we show that AMBN self-associates into ribbon-like supramolecular structures with average widths and thicknesses of 18 and 0.34 nm, respectively. The AMBN ribbons exhibited lengths ranging from tens to hundreds of nm. Deletion analysis and NMR spectroscopy revealed that an N-terminal segment encoded by exon 5 comprises two short independently structured regions and plays a key role in self-assembly of AMBN. 相似文献
909.
910.
Alagille syndrome may mimic biliary atresia in early infancy. Since mutations in JAG1 typical for Alagille syndrome type 1 have also been found in biliary atresia, we aimed to identify JAG1 mutations in newborns with proven biliary atresia (n = 72). Five biliary atresia patients with cholestasis, one additional characteristic feature of Alagille syndrome and ambiguous liver histology were single heterozygotes for nonsense or frameshift mutations in JAG1. No mutations were found in the remaining 67 patients. All “biliary atresia” carriers of JAG1 null mutations developed typical Alagille syndrome at the age of three years. Our data do not support association of biliary atresia with JAG1 mutations, at least in Czech patients. Rapid testing for JAG1 mutations could prevent misdiagnosis of Alagille syndrome in early infancy and improve their outcome. 相似文献