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Recently, in 2020, Stark broadening parameters have been measured for spectral lines belonging to 75 vanadium ii (V  ii) multiplets. For some of them, there are published calculations in the literature. However, these lines are not sufficient for the analysis of the lines present in the metal-poor star HD 8493. When new calculations by the Griem approximation are performed and compared with the experimental results, in some cases there is a difference of a factor of 7. It is clear that the problem lies, as already suggested some years ago in a theoretical paper by Douglas H. Sampson, in the poor approximation proposed by van Regemorter for the Gaunt factors used in the Griem approximation. In this work, we have performed broadening measurements of 3276.12 and 3715.46 Å V  ii lines that confirmed the previous measurements of 2020. Subsequently, we performed a more accurate calculation using the procedure to calculate the Gaunt factors suggested by Sampson, obtaining results very close to the experimental values. These allowed us to assume that the calculations performed for 56 lines ranging between 3700 and 4600 Å (present in the photospheres of the Sun and the metal-poor star HD 8493), and without experimental information, are more accurate using the Gaunt factors proposed by Sampson. [ABSTRACT FROM AUTHOR]

Background: Carbapenem-resistant Enterobacteriaceae (CRE) are an emerging problem in the paediatric population worldwide with high mortality rates in bloodstream infection (BSI).Objectives: To evaluate predictors of 30 day mortality in CRE BSI in a paediatric cohort.Methods: A retrospective observational single-centre study (December 2005-August 2018) was conducted. Cases of CRE BSI in children 0 to 16 years were included. Microbiological identification (MALDI Biotyper) and antimicrobial susceptibility testing (Vitek2® and MicroScan panel NBC44) according to EUCAST breakpoints were performed. PCR OXVIKP® was used to confirm carbapenemase genes (OXA-48, VIM, KPC, NDM). Demographic characteristics, underlying diseases, source of bacteraemia, antimicrobial therapy and outcomes were collected from medical records. Survival analysis to establish predictors of 30 day mortality was performed.Results: Thirty-eight cases were included; 76.3% were hospital-acquired infections and 23.7% related to healthcare. All patients had at least one underlying comorbidity and 52.6% were recipients of an organ transplant. VIM carbapenemase was the predominant mechanism (92.1%). Previous CRE colonization or infection rate was 52.6%. Intestinal tract (26.3%) and vascular catheter (21.1%) were the most common sources of infection. Crude mortality within 30 days was 18.4% (7/38); directly related 30 day mortality was 10.5%. Conditions associated with an increment in 30 day mortality were intensive care admission and inadequate empirical therapy (P < 0.05). Combination-antibiotic targeted treatment and a low meropenem MIC were not related to improved survival.Conclusions: CRE BSI mortality rate is high. The most important factor related to 30 day survival in our CRE BSI cohort in children was empirical treatment that included at least one active antibiotic. [ABSTRACT FROM AUTHOR]

The presence of Hg iii in the stellar atmosphere in the stars HgMn χ Lupi and HR7775 was reported by Leckrone et al. and Proffitt et al. In this last work, the authors indicate that the intensities of the spectral lines of 1360.50, 1647.48, and 1738.54 Å of Hg iii are relatively strong compared to the intensities of the spectral lines of Hg ii. Although the explanation given by the authors in their conclusions should be correct, the values of the oscillator strengths used by the authors in some cases were not consistent with the experimental lifetimes obtained by Henderson et al. In addition, some of the lines studied by the authors are widely overlapped with intense lines of Hg iii of the same multiplet. In this paper, we present values of transition probabilities and line broadening by electron collision (Stark effect) of several lines of Hg iii in order to clarify the problems indicated above. Since Hg iii is a heavy element, we include the core polarization effects (using the Cowan's code) in our calculations. Several values of polarizability, taking Fraga values for Hg iv as a starting point, have been considered in this study in order to obtain theoretical values of those parameters close to the experimental ones. The theoretical values of the lifetimes obtained in this study, close to the experimental ones, were obtained for a polarizability value of 3.5 au. [ABSTRACT FROM AUTHOR]

The presence of singly ionized thallium in the stellar atmosphere of the chemically peculiar star x Lupi was reported by Leckrone et al. in 1999 by analysis of its stellar spectrum obtained with the Goddard High Resolution Spectrograph (GHRS) on board the Hubble Space Telescope. Atomic data about the spectral line of 1307.50 Å and about the hyperfine components of the spectral lines of 1321.71 Å and 1908.64 Å were taken from different sources and used to analyse the isotopic abundance of thallium II in the star X Lupi. From their results the authors concluded that the photosphere of the star presents an anomalous isotopic composition of Tl II. A study of the atomic parameters of Tl II and of the broadening by the Stark effect of its spectral lines (and therefore of the possible overlaps of these lines) can help to clarify the conclusions about the spectral abundance of Tl II in different stars. In this paper we present calculated values of the atomic transition probabilities and Stark broadening parameters for 49 spectral lines of Tl II obtained by using the Cowan code including core polarization effects and the Griem semiempirical approach. Theoretical values of radiative lifetimes for 11 levels (eight with experimental values in the bibliography) are calculated and compared with the experimental values in order to test the quality of our results. Theoretical trends of the Stark width and shift parameters versus the temperature for spectral lines of astrophysical interest are displayed. Trends of our calculated Stark width for the isoelectronic sequence Tl II-Pb III-Bi IV are also displayed. [ABSTRACT FROM AUTHOR]

The presence of spectral lines of bismuth in stellar atmospheres has been reported in different stars. The anomalous values of the spectral intensities of Bi II and Bi III, compared to the theoretical Local Termodinamic Equilibrium (LTE) standards of Bi I/Bi II/Bi III, have been reported in the spectra obtained with theHigh Resolution Spectrograph of the Hubble/Goddard Space Telescope in the chemically peculiar stars HgMn stars χ Lupi and HR 7775. Spectral lines of 1436.8, 1902.3, 2630.9 and 2936.7 Å of Bi II and 1423.4 Å of Bi III were reported and their relative intensities were measured in these studies Litz'en & Wahlgren 2002. These lines are overlapped with spectral lines of 1437.65, 2630.1 and 2937.1 Å of Bi IV. A study of the Stark broadening parameters of Bi IV spectral lines can help to study these overlaps. In this paper, using the Griem semi-empirical approach, we report calculated values of the Stark parameters for 64 spectral lines of Bi IV. The matrix elements used in these calculations have been determined from 17 configurations of Bi IV. They were calculated using the COWAN code including core polarization effects. Data are displayed for an electron density of 1017 cm-3 and temperatures T = 10 000-160 000 K. Also calculated radiative lifetimes for 12 levels with experimental lifetime are presented, in order to test the goodness of our calculations. Theoretical trends of the Stark width and shift parameters versus the temperature for spectral lines of astrophysical interest are displayed. [ABSTRACT FROM AUTHOR]

Emission lines of Mg iv have been detected in the Far Ultraviolet Spectroscopic Explorer (FUSE) spectrum of LS V +46°21 star and in the Space Telescope Imaging Spectrograph (STIS) spectrum of BD +28°4211 star. This fact justifies our interest in providing spectroscopic parameters of Mg iv. Stark broadening parameters for 169 spectral lines of Mg iv have been calculated by using the Griem semi-empirical approach. The matrix elements used in these calculations has been determined from 13 configurations of Mg iv: 2s12p6, 2s22p4ns (n = 3–5), 2s22p4nd (n = 3–5) and 2s22p45g for even parity and 2s22p5, 2s22p4np (n = 3, 4) and 2s22p4nf (n = 4, 5) for odd parity. Our calculations were made by using the Cowan code. Data are presented for an electron density of 1017 cm−3 and temperatures T = 1.0–10.0 (104 K). Also we present calculated values of transition probabilities for 30 spectral lines and radiative lifetimes corresponding to its upper levels. These values were analysed using the data found in the literature. Theoretical trends of the Stark broadening parameters versus the temperature for several lines of astrophysical interest are presented. [ABSTRACT FROM AUTHOR]

In this paper, we present theoretical Stark widths and shifts calculated corresponding to 66 spectral lines of Sn IV. We use the Griem semi-empirical approach and the COWAN computer code. For the intermediate coupling calculations, the standard method of least-squares fitting from experimental energy levels was used. Data are presented for an electron density of 1017 cm-3 and temperatures T = 1.1-5.0 (104 K). The matrix elements used in these calculations have been determined from 34 configurations of Sn IV: 4d10ns(n = 5-10), 4d10nd(n = 5-8), 4d95s², 4d95p², 4d95s5d, 4d85s5p² and 4d105g for even parity and 4d10np(n=5-8), 4d10nf (n= 4-6), 4d95snp(n = 5-8), 4d85s²5p and 4d95snf (n = 4-10) for odd parity. Also, in order to test the matrix elements used in our calculations, we present calculated values of radiative lifetimes of 14 levels of Sn IV. There is good agreement between our calculations and the experimental radiative lifetimes obtained from the bibliography. The spectral lines of Sn IV are observed in UV spectra of HD 149499 B obtained with the Far Ultraviolet Spectroscopic Explorer, the Goddard High Resolution Spectrograph and the International Ultraviolet Explorer. Theoretical trends of the Stark broadening parameter versus the temperature for relevant lines are presented. Also our values of Stark broadening parameters have been compared with the data available in the bibliography. [ABSTRACT FROM AUTHOR]

Background Melanoma is responsible for almost 80% of the deaths attributed to skin cancer. Stem cells, defined by CD133 expression, have been implicated in melanoma tumour growth, but their specific role is still uncertain. Objectives We hypothesized that the phenotypic heterogeneity of human cutaneous melanomas is related to their content of CD133+ cells. Methods We compared the percentages of CD133+ cells in 29 tumours from four classic types of melanoma: lentigo maligna melanoma ( LMM), superficial spreading melanoma, nodular melanoma and acral lentiginous melanoma ( ALM). Also, we compared the percentages of CD133+ cells in melanomas with different degrees of exposure to ultraviolet radiation: 16 melanomas from skin with chronic sun-induced damage and 13 melanomas from skin without such damage. Results We found a statistically significant increase of CD133+ cells in three different contexts: in melanomas arising on skin with signs of chronic sun-induced damage vs. nonexposed skin, in melanomas in situ vs. invasive melanomas, and in LMM vs. ALM. The proportions of CD133+ cells did not differ among samples of normal skin with different degrees of sun exposure. A distinct subpopulation of CD133+ CXCR4+ cancer stem cells ( CSCs) was identified and shown to be related to the invasive phenotype of the tumours. Conclusions Here, we provide evidence showing, for the first time, that an increase in the CD133+ cell content is associated both with melanomas arising on skin with signs of chronic sun-induced damage and in melanomas in situ with better prognosis. Moreover, our study further confirms the existence of a subpopulation of CD133+ CXCR4+ CSCs in cutaneous melanomas with invasive phenotype and poor prognosis. [ABSTRACT FROM AUTHOR]

Inflammation is necessary for survival, but it is also an important cause of human morbidity and mortality, as exemplified by sepsis. During inflammation, cells of the innate immune system are recruited and activated in response to infection, trauma or injury. These cells are activated through receptors, such as Toll-like receptors (TLRs), which recognize microbial ligands such as lipopolysaccharide (LPS). Triggering receptor expressed on myeloid cells (TREM)-1 amplifies the inflammatory response initiated by TLRs, and its expression on the surface of monocytes increases in the presence of TLR ligands. Here we have shown that in monocytes TREM-1 mRNA levels, measured by reverse transcription–polymerase chain reaction (RT–PCR), remained unchanged and TREM-1 protein levels, measured by flow cytometry, increased, indicating that LPS increases TREM-1 expression by a post-transcriptional mechanism. We also showed that TREM-1/Fc fusion protein decreased the ability of the sera of some patients with sepsis to activate monocytes, indicating that the TREM-1 ligand, whose identity is unknown, may be present in the sera of some of these patients. We describe a mechanism for the regulation of TREM-1 expression on monocytes and the possible presence of its ligand in serum; these findings help to explain the contribution of TREM-1 during systemic inflammation. [ABSTRACT FROM AUTHOR]

It has been shown recently that different genotypes ofMycobacterium tuberculosisinduce distinct immune responses in the host, as reflected by variations in cytokine and iNOS expression. Because these molecules are probably regulated by multiple factorsin vivothis complex phenomenon was partially analysed by assessing cytokine and iNOS expression by real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) in anin vitromodel of bone marrow-derived macrophages infected with three differentM. tuberculosisgenotypes: Canetti, H37 Rv and Beijing. Although the three genotypes induced production of iNOS and the different cytokines tested at 24 h post-infection, macrophages infected with the Beijing isolate expressed the highest levels of mRNA for iNOS, interleukin (IL)-1β, tumour necrosis factor (TNF)-α, IL-12 cytokines and lower levels of IL-10 compared with cells infected with other genotypes. This expression pattern has been associated with infection control, but during infectionin vivowith the Beijing genotype it is lost upon progression to chronic phase. The failure to control infection is likely to be influenced by cytokines produced by other cell types and bacterial molecules expressed during the course of disease. Results presented in this work show that each genotype has the ability to induce different levels of cytokine expression that could be related to its pathogenesis during infection. [ABSTRACT FROM AUTHOR]

The activity of sparfloxacin on Staphylococcus epidermidis biofilms on different plastic catheters was evaluated. Sparfloxacin showed high bactericidal activity against S. epidermidis biofilms on Vialon and polyvinylchloride catheters. The combination of sparfloxacin with amikacin or rifampicin significantly increased its activity against bacterial biofilms on polyurethane and Teflon catheters. [ABSTRACT FROM AUTHOR]

Azithromycin is a new macrolide which accumulates in high concentrations in human phagocytes. The cellular to extracellular ratio (C/E) of azithromycin concentrations (fixed extracellular concentration 1 mg/L) in human polymorphonuclear leucocytes (PMN) were significantly affected by small increases in the environmental temperature (C/E 20.3 +/- 2 and 59.4 +/- 6 at 37 degrees C and 40 degrees C, respectively). PMN-associated azithromycin was not affected by the presence of different concentrations of human serum. The intracellular accumulation of azithromycin decreased slightly (C/E approximately 5) when cells were activated with PMA or opsonized with zymosan. The phagocytosis of opsonized Staphylococcus aureus or Haemophilus influenzae, however, slightly increased the intracellular concentrations of azithromycin. At different extracellular concentrations, azithromycin did not affect the production of hydrogen peroxide and superoxide radicals by PMN. The intracellular survival of H. influenzae in human PMN was abolished in the presence of concentrations higher than 0.125 mg/L of azithromycin. Under the same experimental conditions, however, azithromycin did not show any intracellular activity against S. aureus. [ABSTRACT FROM AUTHOR]

The effect of several antimicrobial agents, active against Gram-positive cocci, anaerobes or fungi on the intracellular penetration of ofloxacin and its optically active isomer (-)-ofloxacin into human polymorphonuclear leucocytes (PMNs) was studied. In the presence of therapeutic extracellular concentrations of these drugs, both ofloxacin and (-)-ofloxacin reached high intracellular concentrations (cellular to extracellular ratio (C/E greater than 3). Ofloxacin and (-)-ofloxacin uptake by PMNs was higher when cells were stimulated with opsonized zymosan (C/E greater than 5). It is concluded that none of the antimicrobial agents studied significantly affected the uptake of both quinolones by human PMNs. [ABSTRACT FROM AUTHOR]

Summary: Interpretation of electron tomograms is difficult due to the high noise levels. Thus, denoising techniques are needed to improve the signal-to-noise ratio. XMSF (Microscopy Mean Shift Filtering) is a fast, user-friendly application that succeeds in filtering noise while preserving the structures of interest. It is based on the extension to 3D of a method widely applied in other image processing fields under very different scenarios. XMSF has been tested for a variety of tomograms, showing a great potential to become a state-of-the-art filtering program in electron tomography. Applied iteratively, the algorithm yields pre-segmented volumes facilitating posterior segmentation tasks. Moreover, execution times remain low thanks to parallel computing techniques to exploit current multicore computers.Availability: http://sites.google.com/site/xmsfilter/Contact: jrbcast@ace.ual.es [ABSTRACT FROM PUBLISHER]

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010. [ABSTRACT FROM PUBLISHER]