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681.
The genetic relationships ofAechmea mexicana, A. lueddemanniana, A. macvaughii andA. tuitensis were investigated using starch gel electrophoresis. Eight enzyme systems encoded by ten putative gene loci were resolved in seventeen populations.Nei's (1978) genetic distances were obtained from allelic frequencies and used with UPGMA algorithm. Results indicate that some populations belonging to different species display genetic similarities closer to each other than to some conspecific populations. Our results do not support the proposed genusUrsulaea (Read & Baensch 1994), sinceA. tuitensis was closer toA. lueddemanniana andA. mexicana than toA. macvaughii. 相似文献
682.
683.
Opstelten W Van Wijck AJ Van Essen GA Buskens E Bak AA Kalkman CJ Verheij TJ Moons KG 《BMC anesthesiology》2004,4(1):2-7
BACKGROUND: Postherpetic neuralgia (PHN) is by far the most common complication of herpes zoster (HZ) and one of the most intractable pain disorders. Since PHN is seen most often in the elderly, the number of patients with this disorder is expected to increase in our ageing society. PHN may last for months to years and has a high impact on the quality of life. The results of PHN treatment are rather disappointing. Epidural injection of local anaesthetics and steroids in the acute phase of HZ is a promising therapy for the prevention of PHN. Since randomised trials on the effectiveness of this intervention are lacking, the PINE (Prevention by epidural Injection of postherpetic Neuralgia in the Elderly) study was set up. The PINE study compares the effectiveness and cost-effectiveness of a single epidural injection of local anaesthetics and steroids during the acute phase of HZ with that of care-as-usual (i.e. antivirals and analgesics) in preventing PHN in elderly patients. METHODS / DESIGN: The PINE study is an open, multicenter clinical trial in which 550 elderly (age >/= 50 yr.) patients who consult their general practitioner in the acute phase of HZ (rash < 7 days) are randomised to one of the treatment groups. The primary clinical endpoint is the presence of HZ-related pain one month after the onset of the rash. Secondary endpoints include duration and severity of pain, re-interventions aiming to treat the existing pain, side effects, quality of life, and cost-effectiveness. CONCLUSION: The PINE study is aimed to quantify the (cost-) effectiveness of a single epidural injection during the acute phase of HZ on the prevention of PHN. 相似文献
684.
Several and various types of cells contain fine cytoplasmic filaments closely resembling the myofilaments of muscle cells (2, 18, 23, 24). In many of these cells and especially when cultured, it has been demonstrated that some of these filaments react with heavy meromyosin (HMM) in the same way as do the actin filaments of muscle cells (3, 6 7). This suggests that these filaments may be actinoid and form part of a contractile system. As fine intracytoplasmic filaments do occur in lymphatic endothelial cells (2, 14), we undertook an electron microscope investigation of their fine structure and their reaction on incubation with HMM and EDTA. We postulated that lymphatic endothelial cells possess a contractile filamentous system to which these filaments belong. 相似文献
685.
Detection of Biomarkers of Pathogenic Naegleria fowleri Through Mass Spectrometry and Proteomics 下载免费PDF全文
Hercules Moura Fernando Izquierdo Adrian R. Woolfitt Glauber Wagner Tatiana Pinto Carmen del Aguila John R. Barr 《The Journal of eukaryotic microbiology》2015,62(1):12-20
Emerging methods based on mass spectrometry (MS) can be used in the rapid identification of microorganisms. Thus far, these practical and rapidly evolving methods have mainly been applied to characterize prokaryotes. We applied matrix‐assisted laser‐desorption‐ionization‐time‐of‐flight mass spectrometry MALDI‐TOF MS in the analysis of whole cells of 18 N. fowleri isolates belonging to three genotypes. Fourteen originated from the cerebrospinal fluid or brain tissue of primary amoebic meningoencephalitis patients and four originated from water samples of hot springs, rivers, lakes or municipal water supplies. Whole Naegleria trophozoites grown in axenic cultures were washed and mixed with MALDI matrix. Mass spectra were acquired with a 4700 TOF‐TOF instrument. MALDI‐TOF MS yielded consistent patterns for all isolates examined. Using a combination of novel data processing methods for visual peak comparison, statistical analysis and proteomics database searching we were able to detect several biomarkers that can differentiate all species and isolates studied, along with common biomarkers for all N. fowleri isolates. Naegleria fowleri could be easily separated from other species within the genus Naegleria. A number of peaks detected were tentatively identified. MALDI‐TOF MS fingerprinting is a rapid, reproducible, high‐throughput alternative method for identifying Naegleria isolates. This method has potential for studying eukaryotic agents. 相似文献
686.
Mary J Beilby Christina E Turi Teesha C Baker Fiona JM Tymm Susan J Murch 《Plant signaling & behavior》2015,10(11)
Giant-celled Characeae (Chara australis Brown), grown for 4 months on 12/12 hr day/night cycle and summer/autumn temperatures, exhibited distinct concentration maxima in auxin (indole-3-acetic acid; IAA), melatonin and serotonin about 4 hr after subjective daybreak. These concentration peaks persisted after 3 day pretreatment in continuous darkness: confirming a circadian rhythm, rather than a response to “light on.” The plants pretreated for 3 d in continuous light exhibited several large IAA concentration maxima throughout the 24 hr. The melatonin and serotonin concentrations decreased and were less synchronized with IAA. Chara plants grown on 9/15 hr day/night cycle for 4 months and winter/spring temperatures contained much smaller concentrations of IAA, melatonin and serotonin. The IAA concentration maxima were observed in subjective dark phase. Serotonin concentration peaks were weakly correlated with those of IAA. Melatonin concentration was low and mostly independent of circadian cycle. The “dark” IAA concentration peaks persisted in plants treated for 3 d in the dark. The plants pretreated for 3 d in the light again developed more IAA concentration peaks. In this case the concentration maxima in melatonin and serotonin became more synchronous with those in IAA. The abscisic acid (ABA) and jasmonic acid (JA) concentrations were also measured in plants on winter regime. The ABA concentration did not exhibit circadian pattern, while JA concentration peaks were out of phase with those of IAA. The data are discussed in terms of crosstalk between metabolic pathways. 相似文献
687.
Mogas T Fernández-Novell JM Palomo MJ Otaegui PJ Gomis RR Ballester J Izquierdo D Guinovart JJ Ferrer JC Rigau T Rodríguez-Gil JE 《Biochemical and biophysical research communications》2002,297(4):841-846
Intra-testicular inoculation of an adenoviral vector carrying the fusion gene Aequorea victoria green fluorescence protein/rat-liver glycogen synthase (GFP/LGS) resulted in the presence of GFP/GLS in spermatozoa from 7days to, at least, 16days after inoculation. The GFP/LGS was detected in the sperm heads after an "in vitro" fertilization procedure, either before or after the oocyte penetration. Our results indicate that spermatozoa carrying GFP/LGS protein conserved their fertilizing ability and were also detectable after oocyte penetration. This technique will allow to develop an easy system to follow the fate of mature sperm proteins. 相似文献
688.
Mice of the TO Swiss strain received diets containing different amounts of saturated or unsaturated fat throughout life. These diets produced characteristic changes in cardiac phospholipid fatty acid composition, but produced no significant differences in fatty acid composition of phospholipids from a crude membrane fraction of brain. When littermates of these animals were exposed to ethanol vapour in an inhalation chamber it was observed that mice which had received a diet high in saturated fat lost the righting reflex at an estimated concentration of ethanol in blood higher than that required for mice receiving a control diet, or a diet rich in polyunsaturated fat. Analysis of the brain membrane fraction from those animals which had received ethanol revealed that mice receiving the highly saturated fat diet now had a significantly greater proportion of saturated fatty acids in brain membrane phospholipids. These results are discussed in relation to the hypothesis that brain membrane lipid composition may influence the behavioural response to ethanol. 相似文献
689.
BACKGROUND: Both sorghum (Sorghum bicolor) and sugarcane (Saccharum officinarum) are members of the Andropogoneae tribe in the Poaceae and are each other's closest relatives amongst cultivated plants. Both are relatively recent domesticates and comparatively little of the genetic potential of these taxa and their wild relatives has been captured by breeding programmes to date. This review assesses the genetic gains made by plant breeders since domestication and the progress in the characterization of genetic resources and their utilization in crop improvement for these two related species. GENETIC RESOURCES: The genome of sorghum has recently been sequenced providing a great boost to our knowledge of the evolution of grass genomes and the wealth of diversity within S. bicolor taxa. Molecular analysis of the Sorghum genus has identified close relatives of S. bicolor with novel traits, endosperm structure and composition that may be used to expand the cultivated gene pool. Mutant populations (including TILLING populations) provide a useful addition to genetic resources for this species. Sugarcane is a complex polyploid with a large and variable number of copies of each gene. The wild relatives of sugarcane represent a reservoir of genetic diversity for use in sugarcane improvement. Techniques for quantitative molecular analysis of gene or allele copy number in this genetically complex crop have been developed. SNP discovery and mapping in sugarcane has been advanced by the development of high-throughput techniques for ecoTILLING in sugarcane. Genetic linkage maps of the sugarcane genome are being improved for use in breeding selection. The improvement of both sorghum and sugarcane will be accelerated by the incorporation of more diverse germplasm into the domesticated gene pools using molecular tools and the improved knowledge of these genomes. 相似文献
690.
Alireza Babaei Seyed Reza Tabaei-Aghdaei Morteza Khosh-Khui Reza Omidbaigi Mohammad Reza Naghavi Gerhard D Esselink Marinus JM Smulders 《BMC plant biology》2007,7(1):12