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71.
RICARDO CRUZ DE CARVALHO ANABELA BERNARDES DA SILVA RENATA SOARES ANDRÉ M. ALMEIDA ANA VARELA COELHO JORGE MARQUES DA SILVA CRISTINA BRANQUINHO 《Plant, cell & environment》2014,37(7):1499-1515
All bryophytes evolved desiccation tolerance (DT) mechanisms during the invasion of terrestrial habitats by early land plants. Are these DT mechanisms still present in bryophytes that colonize aquatic habitats? The aquatic bryophyte Fontinalis antipyretica Hedw. was subjected to two drying regimes and alterations in protein profiles and sucrose accumulation during dehydration and rehydration were investigated. Results show that during fast dehydration, there is very little variation in protein profiles, and upon rehydration proteins are leaked. On the other hand, slow dehydration induces changes in both dehydration and rehydration protein profiles, being similar to the protein profiles displayed by the terrestrial bryophytes Physcomitrella patens (Hedw.) Bruch and Schimp. and, to what is comparable with Syntrichia ruralis (Hedw.) F. Weber and D. Mohr. During dehydration there was a reduction in proteins associated with photosynthesis and the cytoskeleton, and an associated accumulation of proteins involved in sugar metabolism and plant defence mechanisms. Upon rehydration, protein accumulation patterns return to control values for both photosynthesis and cytoskeleton whereas proteins associated with sugar metabolism and defence proteins remain high. The current results suggest that bryophytes from different ecological adaptations may share common DT mechanisms. 相似文献
72.
Graham RD Jones Sabrina DA Koetsier 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2014,35(4):243-250
Reference intervals are commonly considered to allow for between-laboratory bias. The RCPAQAP Liquid Serum Chemistry Program has collected data on laboratory measurements as well as reference intervals. This allows assessment of the between-laboratory variation in results, reference intervals and the information transmitted by the combination of these factors. For the majority of common chemistry analytes, the between-laboratory variation in reference intervals is greater than the variation in results. Additionally the reference interval variation is generally not related to bias between the results. Use of common reference intervals, either as an average of the current intervals in use, or the intervals proposed by the AACB Harmonisation Group, improved the variation seen in the information produced by different laboratories. 相似文献
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Indoor and outdoor winter activity of Culicoides biting midges,vectors of bluetongue virus,in Italy
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A. MAGLIANO P. SCARAMOZZINO S. RAVAGNAN F. MONTARSI G. DA ROLD G. CINCINELLI A. MONI P. SILVESTRI A. CARVELLI C. DE LIBERATO 《Medical and veterinary entomology》2018,32(1):70-77
Indoor and outdoor winter activity of Culicoides spp. (Diptera: Ceratopogonidae) in central Italy was investigated in order to evaluate whether indoor activity might account for the overwintering of bluetongue virus, as has been hypothesized by some authors. Weekly Culicoides collections were performed at three farms over three consecutive winter seasons. At each farm, two black‐light traps were operated simultaneously, indoors and outdoors. Culicoides were identified using both morphological and molecular means. The Culicoides obsoletus group accounted for 98.2% of sampled specimens. Within this group, C. obsoletus s.s. accounted for 56.8% and Culicoides scoticus for 43.2% of samples. Nulliparous, parous and engorged females were caught throughout the entire winter, both indoors and outdoors. At times, indoor catch sizes outnumbered outdoor collections. A significant inverse correlation was found between minimum temperature and the proportion of indoor Culicoides of the total midge catch, thus indicating that lower outdoor temperatures drive Culicoides midges indoors. High rates of engorged females were recorded indoors, possibly as the result of the propensity of C. obsoletus females to feed indoors. Higher proportions of parous females were found in indoor than in outdoor catches, indicating higher survival rates indoors and, consequently, higher vectorial capacities of midges sheltering indoors compared with those remaining outdoors. 相似文献
76.
Short-Term In Vitro Culture and Molecular Analysis of the Microsporidian, Enterocytozoon bieneusi 总被引:2,自引:0,他引:2
GOVINDA S. VISVESVARA GORDON J. LEITCH NORMAN J. PIENIAZEK ALEXANDRE J. DA SILVA SARA WALLACE SUSAN B. SLEMENDA RAINER WEBER DAVID A. SCHWARTZ LEO GORELKIN C. MEL WILCOX RALPH T. BRYAN 《The Journal of eukaryotic microbiology》1995,42(5):506-510
ABSTRACT. The microsporidium, Enterocytozoon bieneusi , causes a severe, debilitating, chronic diarrhea in patients with the acquired immunodeficiency syndrome. Specific diagnosis of intestinal microsporidiosis, especially due to Enterocytozoon , is difficult and there is no known therapy that can completely eradicate this parasite. Preliminary studies indicate that a short term (about 6 months) in vitro culture of this parasite yielding low numbers of spores, may be established by inoculating human lung fibroblasts and/or monkey kidney cell cultures with duodenal aspirates and or biopsy from infected patients. The cultures may subsequently be used for the isolation and molecular analysis of parasite DNA. 相似文献
77.
Gram-Chromotrope: a New Technique that Enhances Detection of Microsporidial Spores in Clinical Samples 总被引:3,自引:0,他引:3
HERCULES MOURA JORGE L. NUNES DA SILVA FERNANDO C. SODRÉ PATRICIA BRASIL KRISTY WALLMO SUSANNE WAHLQUIST SARA WALLACE GIAN P. CROPPO GOVINDA S. VISVESVARA 《The Journal of eukaryotic microbiology》1996,43(5):94S-95S
We have developed a new staining procedure that combines the traditional Gram staining for bacteria and the Weber's chromotrope staining method, the standard technique for the detection of microsporidia spores in clinical Specimens. This “Gram-chromotrope” staining technique enhances the staining characteristics of microsporidia spores and facilitates the easy detection and differentiation of spores from other microorganisms that are found in clinical specimens, especially stool samples. This new technique is fast, reliable, and simple to perform, and can be easily adapted for use in clinical laboratories. 相似文献
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79.
Hierarchical genetic structure and gene flow in three sympatric species of Amazonian rodents 总被引:2,自引:0,他引:2
The population genetic structure of three species of Amazonian rodents ( Oligoryzomys microtis, Oryzomys capito , and Mesomys hispidus ) is examined for mtDNA sequence haplotypes of the cytochrome b gene by hierarchical analysis of variance and gene flow estimates based on fixation indices ( N ST ) and coalescence methods. Species samples are from the same localities along 1000 km of the Rio Juruá in western Amazonian Brazil, but each species differs in important life history traits such as population size and reproductive rate. Average haplotype differentiation, hierarchical haplotype apportionment, and gene flow estimates are contrasted in discussing the current and past population structure. Two species exhibit isolation by distance patterns wherein gene flow is largely limited to geographically adjacent localities. Mesomys exhibits this pattern throughout its range along the river. More than 75% of haplotype variation is apportioned among localities and regions, and estimates of Nm for pair-wise comparisons are nearly always less than 1. Oligoryzomys shows weak isolation by distance, but only over the largest geographical distances. Nm values for this species are nearly always above 1 and most (about 80%) of haplotype variation is contained within local populations. In contrast, Oryzomys exhibits no genetic structure throughout its entire distribution; Nm values average 17 and nearly 90% of the total haplotype variance is contained within local populations. Although gene flow estimates are high, the pattern of Nm as a function of geographical distance suggests that this species experienced a more recent invasion of the region and is still in genetic disequilibrium under its current demographic conditions. 相似文献
80.
JOSEPH R. MENDELSON III HELIO R. DA SILVA ANNE M. MAGLIA 《Zoological Journal of the Linnean Society》2000,128(2):125-148
We reassess the phylogenetic relationships of genera of hemiphractine hylid frogs (Marsupial Treefrogs) and discuss the evolution of several distinctive characters within this group using parsimony analysis. Fifty-one morphological and life-history characters were sampled from two species of Cryptobatrachus , three species of Flectonotus , 17 species of Gastrotheca , all five species of Hemiphractus , and one species of Stefania as the ingroup and three hyline, one phyllomedusine, and one pelodryadine species as outgroups. Our results support the mon-ophyly of Flectonotus, Cryptobatrachus , and Hemiphractus. Gastrotheca is paraphyletic with respect to Hemiphractus , dorsal pouches were lost in the ancestor of Hemiphractus. Direct development is a synapomorphy for Hemiphractinae and tadpoles were regained independently several times. These results stand in stark contrast to the prevailing paradigm regarding marsupial frog relationships. 相似文献