7,056 research outputs found
Programmed schedule holds for improving launch vehicle holds
Baseline definition and system optimization are used for the analysis of programmed holds developed through prelaunch system analysis. Identification of design specifications for ground support equipment and maintenance concepts, and design specifications are used to describe the functional utilization of the overall flow process
Isoflavones and other compounds from the roots of Iris marsica I. Ricci E Colas. Collected from Majella National Park, Italy
In this study, a phytochemical analysis was performed, for the first time, on Iris marsica I. Ricci e Colas. In particular, the attention was focused on the constituents of the roots. Twenty-one compounds were isolated by column chromatography and were analyzed/identified by NMR spectroscopy and mass spectrometry. They all own chemotaxonomic, ethno-pharmacological and nutraceutical relevance which allowed us to provide a phytochemical rationale, for the correct botanical classification of this species, for the employment of its roots in folk medicine like for all the other species belonging to the Iris genus and, lastly, for their further uses as food with important healthy benefits. All of these parts were broadly discussed about within the text
The surface accessibility of α-bungarotoxin monitored by a novel paramagnetic probe
The surface accessibility of {alpha}-bungarotoxin has been investigated by using Gd2L7, a newly designed paramagnetic NMR probe. Signal attenuations induced by Gd2L7 on {alpha}-bungarotoxin C{alpha}H peaks of 1H-13C HSQC spectra have been analyzed and compared with the ones previously obtained in the presence of GdDTPA-BMA. In spite of the different molecular size and shape, for the two probes a common pathway of approach to the {alpha}-bungarotoxin surface can be observed with an equally enhanced access of both GdDTPA-BMA and Gd2L7 towards the protein surface side where the binding site is located. Molecular dynamics simulations suggest that protein backbone flexibility and surface hydration contribute to the observed preferential approach of both gadolinium complexes specifically to the part of the {alpha}-bungarotoxin surface which is involved in the interaction with its physiological target, the nicotinic acetylcholine receptor
The intrinsic topological information of the wild-type and of up-promoter mutations of the Saccharomyces cerevisiae alcohol dehydrogenase II regulatory region.
A 569-base pair fragment encompassing the upstream regulatory region, the RNA initiation sites, and the initial part of the coding region of the Saccharomyces cerevisiae alcohol dehydrogenase II gene has been analyzed for the presence of sites which undergo conformational modification under torsional stress. Fine mapping of P1 and S1 endonuclease-sensitive sites was obtained on single topoisomers produced by in vitro ligation. It was shown that the upstream activator sequence, the TATA sequence, a region directly upstream to the RNA initiation sites, and several positions in the first segment of the transcribed region change conformation as a function of the applied torsional stress in a precisely coordinate fashion. The superhelical density optima for this coordinate modifications have been determined. Analysis of the conformational changes of the promoter sequence in several naturally occurring (Young, E. T., Williamson, V. M., Taguchi, A., Smith, M., Sledziewski, L., Russel, D., Osterman, J., Denis, C., Cox, D., and Beier, D., (1982) in Genetic Engineering of Microorganisms for Chemicals (Hollander, A., De Moss, R. D., Kaplan, S., Konisky, J., Savage, D., and Wolle, R. S., eds) pp. 335-361, Plenum Publishing Corp., New York) up-promoter constitutive mutants was performed. This analysis has shown that the conformation of functionally relevant sites changes as a function of sequence mutations that have taken place elsewhere; this shows that the conformational behavior of the whole promoter region is linked and suggests transmission in cis of topological effects in RNA polymerase II promoters
Essential oil composition and polar fraction analysis of Tanacetum macrophyllum (Waldst. et Kit.) Schultz Bip.
Tanacetum macrophyllum (Waldst. et Kit.) Schultz Bip, also known as Tansy, is a perennial herbaceous plant belonging to the Asteraceae family. This species is typical of the Balcan area but is punctually spread in other European countries as a rare species [1]. In Italy, it is found mainly within forests [1, 2]. This species is often erroneously confused with Achillea grandifolia Friv. [1, 2]. In this work, a comprehensive phytochemical analysis on the volatile components and polar fraction of T. macrophyllum growing in central Italy was carried out. Flowers and leaves were separately analyzed for the essential oil composition and were characterized by oxygenated monoterpenes (39.4%) and oxygenated sesquiterpenes (28.0%) and sesquiterpene hydrocarbons (39.3%) and oxygenated monoterpenes (25.4%), respectively. The phytochemical analysis conducted on the ethanolic extract of the total aerial parts evidenced the presence of twelve compounds: apigenin, cirsimaritin, apigenin-7-O-glucoside, apigenin-7-O-glucuronide, kaempferol-7-O-glucoside, kaempferol-7-O-glucuronide, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, chlorogenic acid, shikimic acid, quinic acid and 4-O-β-D-glucopyranosyl-vanillic acid. Most of these compounds were reported for the first time in the species while three of them are new phytochemicals for the Tanacetum genus. The presence of all these compounds provides a phytochemical rationale for the botanical classification of this species and encourages further ethno-pharmacological studies just like for T. parthenium [3]
A case of persistent bacteraemia by Ralstonia mannitolilytica and Ralstonia pickettii in an intensive care unit
The Ralstonia spp. genus is a group of non-fermentative, Gram-negative bacteria often resistant to many antibiotics, which are emerging as opportunistic pathogens frequently associated with infections in hospital settings. We present herein a case of combined R. pickettii and R. mannitolilytica persisting and relapsing bacteraemia, possibly caused by a septic arterial thrombosis secondary to the rupture of an internal carotid artery aneurysm. Microbiology studies showed that both Ralstonia isolates produced biofilm and carried class D oxacillinase genes. When confronted with infections caused by members of the Ralstonia genus, identification to the species level is crucial for correct clinical management, as the two species show different antibiotic susceptibility patterns
Idiopathic thrombocytopenic purpura: current concepts in pathophysiology and management.
Idiopathic thrombocytopenic purpura (ITP) is characterized by
a low platelet count, which is the result of both increased pla-
telet destruction and insufficient platelet production. Although
the development of autoantibodies against platelet glycoproteins remains central in the pathophysiology of ITP, several abnormalities involving the cellular mechanisms of immune modu-
lation have been identified. Conventional treatments for ITP aim
at reducing platelet destruction, either by immunosuppression or splenectomy. Two new thrombopoietic agents,AMG 531 and eltrombopag, have been used in clinical trials to stimulate platelet production in ITP patients not responsive to standard
treatments. These new molecules bear no structural resemblance to thrombopoietin, but still bind and activate the thrombopoietin receptor. This review will focus on the pathophysiology and treatment of ITP in adults, highlighting recent advances
in both fields
The use of ash at Late Lower Paleolithic Qesem Cave, Israel—An integrated study of use-wear and residue analysis
Employing an integrated approach to investigate the use of Late Lower Paleolithic flint tools
found at the site of Qesem Cave (Israel), we revealed a particular trace pattern related to
the employment of ashes at the site. Using a designated collection of replica items and combining
use-wear and residue (morphological analysis, FTIR, SEM-EDX) analyses, we
revealed the intentional use of ashes in preserving foods for delayed consumption as well
as hide for delayed processing. Our interpretation, we believe is the most plausible one
since we were able to delineate the specific use-wear fingerprints of the intentional use of
ashes for such purposes, suggesting that our approach might be useful for the recognition
of other similar functional-behavioral patterns. Lastly, in support of previous findings at
Qesem Cave, our current findings present evidence for the processing of organic matters
intentionally mixed with ash, leading us to suggest that the inhabitants of Qesem Cave were
proficient not only in the habitual use of fire but also of its main by-product, ash. Hence, we
call for a reassessment of the timeline currently assigned to hominins’ utilization of ash for
storing and processing vegetal foods and hide
Superinfections in patients treated with teicoplanin as anti SARSCoV2 AGENT
We read with interest the paper by Giacobbe et al. estimating a cumulative risk of developing at least one bloodstream infection (BSI) episode (largely due to Gram-positive pathogens) of almost 50% after 30 days at risk in (2) Similarly, Somers et al. reported an increased risk to develop bacterial superinfections, principally represented by Staphylococcus aureus ventilatory associated pneumonia (VAP), in critically ill patients infected with SARS-CoV-2 and treated with Tocilizumab. (1) We previously described a cohort of intubated patients affected by severe COVID-19pneumonia treated with the best available therapy (BAT), including Tocilizumab and associated with Teicoplanin. (3) This glycopeptide antibiotic was used with a double purpose: as antiviral agent for COVID-19 and as of possible S.aureus superinfection
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