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21.
Abstract: The two odontocete taxa Squalodon grateloupii and Patriocetus ehrlichii, both the type species of their respective genera, have been at the centre of a great deal of taxonomic confusion. Originally regarded to be conspecific, these two taxa have been the subject of a bewildering taxonomic debate lasting for more than a century, which recently led to the suggestion to abandon these widely used names and replace S. grateloupii with the similar, yet independently and later proposed name S. gratelupi as the type species of Squalodon. Here, we attempt to summarise the events leading to the current confused situation in the hope of resolving this issue once and for all and argue that the name Squalodon grateloupii, as originally proposed, should be reinstated. 相似文献
22.
Miroslava Chalupova Anna Skalova Tomas Hajek Lenka Geigerova Dana Kralova Pavel Liska Hana Hecova Jiri Molacek Jaroslav Hrabak 《Folia microbiologica》2018,63(6):707-711
Nowadays, dental diseases are one of the most common illnesses in the world. Some of them can lead to translocation of oral bacteria to the bloodstream causing intermittent bacteraemia. Therefore, a potential association between oral infection and cardiovascular diseases has been discussed in recent years as a result of adhesion of oral microbes to the heart valves. The aim of this study was to detect oral bacteria on pathologically changed heart valves not caused by infective endocarditis. In the study, patients with pathologically changed heart valves were involved. Samples of heart valves removed during heart valve replacement surgery were cut into two parts. One aliquot was cultivated aerobically and anaerobically. Bacterial DNA was extracted using Ultra-Deep Microbiome Prep (Molzym GmbH, Bremen, Germany) followed by a 16S rRNA gene PCR amplification using Mastermix 16S Complete kit (Molzym GmbH, Bremen, Germany). Positive PCR products were sequenced and the sequences were analyzed using BLAST database (http://www.ncbi.nlm.nih/BLAST). During the study period, 41 samples were processed. Bacterial DNA of the following bacteria was detected in 21 samples: Cutibacterium acnes (formerly Propionibacterium acnes) (n?=?11; 52.38% of patients with positive bacterial DNA detection), Staphylococcus sp. (n?=?9; 42.86%), Streptococcus sp. (n?=?1; 4.76%), Streptococcus sanguinis (n?=?4; 19.05%), Streptococcus oralis (n?=?1; 4.76%), Carnobacterium sp. (n?=?1; 4.76%), Bacillus sp. (n?=?2; 9.52%), and Bergeyella sp. (n?=?1; 4.76%). In nine samples, multiple bacteria were found. Our results showed significant appearance of bacteria on pathologically changed heart valves in patients with no symptoms of infective endocarditis. 相似文献
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24.
The optimal pH value of a lipase from Pseudomonas fragi was between 7.5 and 8.9, and a high reaction rate was observed at 54 C. Heating the enzyme solution at 63 C for 30 min inactivated only 27.6% of its activity; however, total inactivation was observed at 66 C after 1 hr and at 71 C after 10 min. The lipase was inhibited strongly by Fe+++ and Fe++ ions, and to a lesser extent by Co++, Cu++, Zn++. No inhibition was observed with Ca++ or NaF. Ethylenediaminetetraacetate was effective in removing the toxicity of Fe+++. The activity of the enzyme was inhibited markedly by p-chloromercurobenzoate, but the effects of N-ethylmaleimide and iodoacetate were moderate. The enzyme was able to hydrolyze natural fats, synthetic triglycerides, and alcohol esters. The order of the rate of hydrolysis of some triglycerides under experimental conditions was, from the fastest to the lowest, trilaurin, tricaprin, tricaprylin, tripalmitin, tributyrin, tricaproin, and tristearin. The enzyme was capable of hydrolyzing methyl butyrate, but the rate of hydrolysis was about one-fifth that for triolein and one-thirteenth that for coconut oil. The enzyme lost its activity rapidly when held frozen, at 20 C, and at the extremes in pH. Glutathione, cysteine, and mercaptoethanol did not preserve the activity of the enzyme. 相似文献
25.
J. Liska 《Human Evolution》1987,2(3):205-212
This paper summarizes and applies a continuum of «arbitrariness» or «symbolicity» composed of symptoms, rituals and symbols to the results of research in which American Sign Language (ASL) was used as the method of «language» training. Additionally, an expansion of the symbolicity continuum to include a continuum of «abstractness» with the «conceptual symbol» anchoring the most arbitrary end of the continuum was advanced. The results of the comparison provide additional support for the claim that apes are capable of learning and using symbolic signs. However, only a small number of those symbolic signs could be considered «conceptual symbols». 相似文献
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27.
Deann J. Liska Richard Hawkins Kristina Wikstrom Paul Bornstein 《Journal of cellular physiology》1994,158(3):495-505
The thrombospondins (TSPs) are a family of extracellular glycoproteins that display distinct patterns of temporal and spatial expression during development. In this study, we investigated the expression of two of the TSPs–TPS1 and TSP2– during the course of differentiation of embryonal carcinoma cells in vitro. We report that both TSP1 and TSP2 mRNA and protein synthesis are induced during the differentiation of P19EC cells into neurons, glial cells, and fibroblasts. Immunofluorescence studies indicate that TSP1 displays a fibrillar pattern of staining, characteristic of an extracellular matrix protein, in differentiated P19EC cells. In contrast, TSP2 is cell-associated and is present on differentiated P19EC cells and on primary neurons and glial cells obtained from a 17-day embyronic mouse cerebral cortex. Interestingly, although both TSP1 and TSP2 are more prevalent in areas of differentiated cells, they display distinct patterns of deposition. These observations suggest that TSP1 and TSP2 may function differently during neurogenesis. The response of TSP1 and TSP2 to differentiation of P19EC cells indicates that this cell system will serve as a valuable model for the study of TSP expression and function during neurogenesis. © 1994 Wiley-Liss, Inc. 相似文献
28.
Anna Aminoff Helena Ledmyr Petra Thulin Kerstin Lundell Leyla Nunez Elisabeth Strandhagen Charlotte Murphy Ulf Lidberg Jukka Westerbacka Anders Franco-Cereceda Jan Liska Lars Bo Nielsen Mats G?fvels Maria Nastase Mannila Anders Hamsten Hannele Yki-J?rvinen Dag Thelle Per Eriksson Jan Borén Ewa Ehrenborg 《Journal of lipid research》2010,51(1):103-111
29.
Accumulated dust samples were collected from the heating ducts in a household where signs resembling ochratoxin poisoning
in animals occurred. Several Penicillium spp. and Aspergillus ochraceous had been identified previously from air samples taken from this house. A composite sample from six collected samples was
examined by HPLC, and it was determined that 58 ppb of ochratoxin A was present in this sample. A second set of six samples
was collected and determinations were made by HPLC of the ochratoxin content in each sample. All samples, including one sample
of dirt from a crawl space, yielded at least a trace of ochratoxin A; however, one sample of dust collected from the heating
ducts yielded over 1500 ppb of ochratoxin A, and another sample of dust from a different heating duct yielded 306 ppb of ochratoxin
A. Ochratoxin A was confirmed in all samples by LC-MS, and ochratoxin was evident in the samples by TLC analysis. This is
believed to be the first report of finding ochratoxin inhouse dust.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
30.
Enhanced photosynthesis and redox energy production contribute to salinity tolerance in Dunaliella as revealed by homology-based proteomics 总被引:11,自引:0,他引:11
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Salinity is a major limiting factor for the proliferation of plants and inhibits central metabolic activities such as photosynthesis. The halotolerant green alga Dunaliella can adapt to hypersaline environments and is considered a model photosynthetic organism for salinity tolerance. To clarify the molecular basis for salinity tolerance, a proteomic approach has been applied for identification of salt-induced proteins in Dunaliella. Seventy-six salt-induced proteins were selected from two-dimensional gel separations of different subcellular fractions and analyzed by mass spectrometry (MS). Application of nanoelectrospray mass spectrometry, combined with sequence-similarity database-searching algorithms, MS BLAST and MultiTag, enabled identification of 80% of the salt-induced proteins. Salinity stress up-regulated key enzymes in the Calvin cycle, starch mobilization, and redox energy production; regulatory factors in protein biosynthesis and degradation; and a homolog of a bacterial Na(+)-redox transporters. The results indicate that Dunaliella responds to high salinity by enhancement of photosynthetic CO(2) assimilation and by diversion of carbon and energy resources for synthesis of glycerol, the osmotic element in Dunaliella. The ability of Dunaliella to enhance photosynthetic activity at high salinity is remarkable because, in most plants and cyanobacteria, salt stress inhibits photosynthesis. The results demonstrated the power of MS BLAST searches for the identification of proteins in organisms whose genomes are not known and paved the way for dissecting molecular mechanisms of salinity tolerance in algae and higher plants. 相似文献