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Susceptibility Data (susceptibility + data)
Kinds of Susceptibility Data Selected AbstractsBulky Pyrazolate-Based Compartmental Ligand Scaffolds: Encapsulation of an Edge-Sharing Cu6O2 Bitetrahedral Core,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 34 2008Anna Sachse Abstract Upon reaction with Cu(OAc)2·H2O, pyrazole-based ligands with two appended imine chelate arms in the 3- and 5-positions of the pyrazole and bulky substituents at the imine-N yield Cu6 complexes [L2Cu6(,-OAc)6(,4 -O)2] (1a,b). They feature an unusual {Cu6(,4 -O)2}-bitetrahedral core, only the second example of this structural motif. ESI mass spectrometric and UV/Vis data confirm that the Cu6 complexes stay intact in solution, and magnetic and high-field EPR measurements reveal an S = 0 ground state with the first excited triplet at ,E , 95 cm,1. Although the new hexanuclear systems are too complex for deriving all individual exchange constants from powder susceptibility data, a rough idea of the complete energy level spectrum could be obtained.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Tetranuclear Nickel Complexes Composed of Pairs of Dinuclear LNi2 Fragments Linked by 4,4,-Bipyrazolyl, 1,4-Bis(4,-pyrazolyl)benzene, and 4,4,-Bipyridazine: Synthesis, Structures, and Magnetic PropertiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2007Vasile Lozan Abstract The ability of the ligands 4,4,-bipyrazolyl (H2bpz), 1,4-bis(4,-pyrazolyl)benzene (H2bpzb), and 4,4,-bipyridazine (bpdz) to link two dioctahedral LNi2 units has been examined. Thefollowing complexes were prepared: [L1NiII2(Hbpz)][BPh4] (6[BPh4]), [L1NiII2(bpdz)][ClO4]2 (7[ClO4]2), [(L1NiII2)2(bpzb)][BPh4]2 (8[BPh4]2), and [(L2NiII2)2(bpz)][BPh4]2 (9[BPh4]2), where (L1)2, and (L2)2, represent macrocyclic hexaaza-dithiophenolate ligands. All complexes have been characterised by UV/Vis spectroscopy, IR spectroscopy, and X-ray crystallography. Whereas (Hbpz), and bpdz in 6[BPh4]2 and 7[ClO4]2 act as bidentate ligands coordinating to only one [LNi2]2+ unit, in 8[BPh4]2 and 9[BPh4]2 the (bpzb)2, and(bpz)2, units are tetradentate linkers. This is qualitatively explained in terms of the absence or presence of steric repulsions between the tBu groups of the supporting ligands and the length of the coligands. The structures of the tetranuclear complexes differ mainly in the distance between the center of the Ni···Ni axes of the isostructural [LNi2] units {14.040(1) Å in 8[BPh4]2, 9.184(1) Å in 9[BPh4]2}. The two Ni2pyrazolato planes in 9[BPh4]2 are coplanar. An analysis of the temperature-dependent magnetic susceptibility data for 9[BPh4]2 reveals the presence of weak ferromagnetic exchange interactions between the NiII ions in the binuclear [L2Ni2] subunits with values for the magnetic exchange constant J1 of 23.97 cm,1 (H = ,2JS1S2). The exchange coupling across the dipyrazolato bridge is less than 0.1 cm,1, suggesting that no significant interdimer exchange coupling occurs in 9[BPh4]2. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Coordination Chemistry of N,N,N,,N, -Tetraethylpyridine-2,6-dithiocarboxamide (S -dept) , X-ray Crystal Structures and Magnetic Properties of [Co(S -dept)X2] (X = Br, I, and NCS)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2005Ramesh Kapoor Abstract Mononuclear cobalt(II) complexes [Co(S -dept)X2] [X = Br (1), I (2) and NCS (3)] were synthesized using N,N,N,,N, -tetraethylpyridine-2,6-dithiocarboxamide (S -dept), and characterised by conductivity, spectral and single-crystal X-ray diffraction studies. These studies reveal that the compounds consist of discrete monomeric molecules in which the cobalt atoms are five-coordinate in an environment that is best described as being distorted square-pyramidal. In dimethylformamide the iodo complex shows significant ionic dissociation (1:1 electrolyte) and its crystal field absorption spectrum is interpretable in terms of an octahedral structure [Co(S -dept)(DMF)2I]+. The temperature dependence of the magnetic susceptibility data is indicative of a high-spin compound with an important zero-field splitting. The best fitwas obtained with |D| = 20.5 cm,1 and g = 2.53 for 1, |D| = 14.2 cm,1 and g = 2.38 for 2 and |D| = 17.7 cm,1 and g = 2.35 for 3. The X-band EPR spectra at low temperature is also characteristic of an S = 3/2 state with important zero-field splitting. The most important band appears at low fields (ca. 1200 G). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] In situ identification, pairing, and classification of meteorites from Antarctica through magnetic susceptibility measurementsMETEORITICS & PLANETARY SCIENCE, Issue 3 2006Luigi Folco Magnetic susceptibility measurements carried out with a pocket meter (SM30) during the 2003/04 PNRA meteorite collection expedition to northern Victoria Land (Antarctica) proved to be a rapid, sensitive, non-destructive means for the in situ identification, pairing, and classification of meteorites. In blue ice fields characterized by the presence of moraines and glacial drifts (e.g., Miller Butte, Roberts Butte, and Frontier Mountain), magnetic susceptibility measurements allowed discrimination of meteorites from abundant terrestrial stones that look like meteorites thanks to the relatively high magnetic susceptibility of the former with respect to terrestrial rocks. Comparative measurements helped identify 16 paired fragments found at Johannessen Nunataks, thereby reducing unnecessary duplication of laboratory analyses and statistical bias. Following classifications schemes developed by us in this and previous works, magnetic susceptibility measurements also helped classify stony meteorites directly in the field, thereby providing a means for selecting samples with higher research priority. A magnetic gradiometer capable of detecting perturbations in the Earth's magnetic field induced by the presence of meteorites was an efficient tool for locating meteorites buried in snow along the downwind margin of the Frontier Mountain blue ice field. Based on these results, we believe that magnetic sensors should constitute an additional payload for robotic search for meteorites on the Antarctic ice sheet and, by extension, on the surface of Mars where meteorite accumulations are predicted by theoretical works. Lastly, magnetic susceptibility data was successfully used to crosscheck the later petrographic classification of the 123 recovered meteorites, allowing the detection of misclassified or peculiar specimens. [source] Antimicrobial and anti-inflammatory activity of five Taxandria fragrans oils in vitroMICROBIOLOGY AND IMMUNOLOGY, Issue 11 2008Katherine A. Hammer ABSTRACT The antimicrobial activity of five samples of Taxandria fragrans essential oil was evaluated against a range of Gram-positive (n= 26) and Gram-negative bacteria (n= 39) and yeasts (n= 10). The majority of organisms were inhibited and/or killed at concentrations ranging from 0.06,4.0% v/v. Geometric means of MIC were lowest for oil Z (0.77% v/v), followed by oils X (0.86%), C (1.12%), A (1.23%) and B (1.24%). Despite differences in susceptibility data between oils, oils A and X did not differ when tested at 2% v/v in a time kill assay against Staphylococcus aureus. Cytotoxicity assays using peripheral blood mononuclear cells demonstrated that T. fragrans oil was cytotoxic at 0.004% v/v but not at 0.002%. Exposure to one or more of the oils at concentrations of ,0.002% v/v resulted in a dose responsive reduction in the production of proinflammatory cytokines IL-6 and TNF-,, regulatory cytokine IL-10, Th1 cytokine IFN-, and Th2 cytokines IL-5 and IL-13 by PHA stimulated mononuclear cells. Oil B inhibited the production of all cytokines except IL-10, oil X inhibited TNF-,, IL-6 and IL-10, oil A inhibited TNF-, and IL-6, oil C inhibited IL-5 and IL-6 and oil Z inhibited IL-13 only. IL-6 production was significantly inhibited by the most oils (A, B, C and X), followed by TNF-, (oils A, B and X). In conclusion, T. fragrans oil showed both antimicrobial and anti-inflammatory activity in vitro, however, the clinical relevance of this remains to be determined. [source] Clinically relevant drug interactions of current antifungal agentsMYCOSES, Issue 2 2010Paul O. Gubbins Summary Antifungal agents are often prescribed in critically ill patients who are receiving many other medications. When using systemic antifungals, clinicians may possess susceptibility data and they are typically aware of the potential toxicity of these agents. However, the myriad of potential drugs that antifungal agents can interact with is daunting and can be confusing. This article reviews the pharmacokinetic properties of antifungal agents and their clinically relevant drug interactions. The antifungal agents differ markedly in their pharmacokinetic properties and in how they interact with other medicines. The amphotericin B formulations interact with other medicines primarily by reducing their renal elimination or producing additive toxicities. The azoles interact with other medicines primarily by inhibiting biotransformation or by affecting drug distribution and elimination. The echinocandins have the lowest propensity to interact with other medicines. The clinical relevance of antifungal,drug interactions varies substantially. While certain interactions are benign and result in little or no untoward clinical outcomes, others can produce significant toxicity or compromise efficacy if not properly managed through monitoring and dosage adjustment. However, certain interactions produce significant toxicity or compromise efficacy to such an extent that they cannot be managed and the particular combination of antifungal and interacting medicine should be avoided. [source] PRESELI DOLERITE BLUESTONES: AXE-HEADS, STONEHENGE MONOLITHS, AND OUTCROP SOURCESOXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2006OLWEN WILLIAMS-THORPE Summary. Chemical compositions and magnetic susceptibility data were compared for 12 dolerite bluestone implements including axes, axe-hammers and battle-axes, 11 Stonehenge monoliths (chemical data only), and potential source outcrops in Preseli, South Wales. Most of the studied artefacts are of spotted dolerite, a small number being unspotted dolerite. Bivariate graphs, discriminant analysis and t-tests were used singly and in combination to show, respectively, that the implements found at sites in England are mainly similar to Stonehenge monoliths, while the implements found in Wales have a variety of compositions and are much less similar to Stonehenge monoliths. The dichotomy between English and Welsh dolerite bluestone implements could be explained by exploitation of different Preseli outcrops or erratic assemblages derived from them. A small number of spotted dolerite implements have previously been shown to have chemical compositions atypical of and marginal to Preseli, suggesting the possibility of a source of spotted dolerite outside Preseli. Previously published analytical data in combination with the new implement/outcrop comparisons presented in this paper support derivation of the majority of analysed Stonehenge monoliths at one particular outcrop within the group of four identified by Thorpe et al. 15 years ago. Analysis of all the extant bluestone monoliths at Stonehenge (now possible using non-destructive methods) would allow progress in identifying monolith outcrop sources, and in understanding the links with the bluestone axe trade. [source] Population antibiotic susceptibility for Streptococcus pneumoniae and treatment outcomes in common respiratory tract infections,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 1 2006Jon P. Furuno PhD Abstract Purpose Antibiotic-resistant Streptococcus pneumoniae potentially threatens the successful treatment of common respiratory tract infections (RTIs); however, the relationship between antibiotic resistance and treatment outcomes remains unclear. We aimed to test the hypothesis that higher in vitro penicillin and erythromycin nonsusceptibility levels among clinical isolates of S. pneumoniae are associated with higher risk of treatment failure in suppurative acute otitis media (AOM), acute sinusitis, and acute exacerbation of chronic bronchitis (AECB). Methods We conducted a population-level analysis using treatment outcomes data from a national, managed-care claims database, and antibiotic susceptibility data from a national repository of antimicrobial susceptibility results between 1997 and 2000. Treatment outcomes in patients with suppurative AOM, acute sinusitis, or AECB receiving selected macrolides or beta-lactams were assessed. Associations between RTI-specific treatment outcomes and antibiotic nonsusceptibility were determined using Spearman correlation coefficients with condition-specific paired outcome and susceptibility data for each region and each year. Results There were 649,552 available RTI outcomes and 7252 susceptibility tests performed on S. pneumoniae isolates. There were no statistically significant trends across time for resolution proportions following treatment by either beta-lactams or macrolides among any of the RTIs. Correlation analyses found no statistically significant association between S. pneumoniae susceptibility and RTI treatment outcomes apart from a significant positive association between of erythromycin nonsusceptibility in ear isolates and macrolide treatment resolution for suppurative AOM. Conclusion On the population level, in vitroS. pneumoniae nonsusceptibility to macrolide or beta-lactam antibiotics was not associated with treatment failure in conditions of probable S. pneumoniae etiology. Copyright © 2005 John Wiley & Sons, Ltd. [source] Isosymmetrical phase transition in ,-YbV4O8ACTA CRYSTALLOGRAPHICA SECTION B, Issue 6 2008Karen Friese The structure of YbV4O8 is related to the CaFe2O4 structure type. VO6 octahedra form a three-dimensional framework with tunnels in which the Yb3+ ions are incorporated. Two different polymorphs , and , are known and differ mainly in the arrangement of the Yb ions within the framework. We studied the structure and magnetic properties of ,-YbV4O8 as a function of temperature. At approximately 70,K ,-YbV4O8 undergoes a first-order isosymmetrical phase transition (P21/n,P21/n). While in the high-temperature , phase the three V3+ and one V4+ are disordered over the four symmetrically independent octahedral sites, in the low-temperature ,, phase complete charge ordering is observed. The transition is accompanied by a paramagnetic,paramagnetic anomaly in the magnetic susceptibility data which can be interpreted on the basis of spin-gap formation. The transition mechanism in the , polymorph is very similar to that observed earlier in the , polymorph at 185,K. [source] Exploring the location and function of a Late Neolithic house at Crossiecrown, Orkney by geophysical, geochemical and soil micromorphological methodsARCHAEOLOGICAL PROSPECTION, Issue 1 2010Richard Jones Abstract Magnetic prospection was instrumental in the discovery of a multiphase Neolithic settlement at Crossiecrown on Mainland Orkney. Subsequent excavation revealed a number of structures, including a large circular walled house of Late Neolithic date with a range of well-defined architectural features in its interior. This paper presents the discovery, excavation and in particular the functional analysis of this house. Soil micromorphology established the sequence from the house's initial floor construction to its abandonment. On the basis of multi-element and magnetic susceptibility data obtained from analysis of samples taken from the floor of the house, several element distributions were found to be distinctive in the way they correlated with some of the house's ,fixed furniture' and moreover with the distributions of certain artefacts, notably the stone tools. The archaeological implications of these findings are discussed. Copyright © 2010 John Wiley & Sons, Ltd. [source] In vitro susceptibility to 17 antimicrobials of clinical Clostridium difficile isolates collected in 1993,2007 in SwedenCLINICAL MICROBIOLOGY AND INFECTION, Issue 8 2010T. Norén Clin Microbiol Infect 2010; 16: 1104,1110 Abstract This study investigated the MICs of 17 antimicrobials, for 606 toxigenic clinical isolates of Clostridium difficile collected between 1993 and 2007 in Sweden. Low MIC90 values were found for metronidazole (0.5 mg/L), vancomycin (1.0 mg/L), teicoplanin (0.125 mg/L), fusidic acid (1.0 mg/L), linezolid (2.0 mg/L), daptomycin (2.0 mg/L) and tigecycline (0.064 mg/L). Three isolates (0.5%) had elevated MICs for vancomycin (4,8 mg/L); however, these isolates originated from the same patient, who was receiving long-term intravenous vancomycin treatment. High-level clindamycin resistant isolates (MIC >256 mg/L) peaked in 1997 with 39 of 95 (41%) and out of these, 36% were also highly resistant to erythromycin. ,-Lactams such as penicillin V and piperacillin displayed MIC90s of 8 and 32 mg/L, respectively, whereas MICs of cefuroxime were >256 mg/L for all isolates. Universal resistance to ciprofloxacin and levofloxacin was found, and resistance to moxifloxacin increased from 4% of isolates in 2004 to 23% in 2007. Notably, these moxifloxacin-resistant isolates did not belong to the recent epidemic PCR ribotype 027, but to the pre-existing epidemic type 012 (82%), and these isolates accounted for the majority of isolates that were resistant to clindamycin (70%), tetracycline (84%) and rifampicin (92%) as well. This investigation of susceptibility data on clinical C. difficile isolates showed variations of multiresistance to be due to a specific PCR ribotype 012, emphasizing the importance of genotyping when evaluating emerging resistance over time. [source] | |||||||||||||