369 research outputs found
Results from a randomized, controlled trial on efficacy and tolerability of a 5% Lidocaine-Medicated Plaster vs. Pregabalin in patients with Post-Herpetic Neuralgia (PHN) and Painful Diabetic Polyneuropathy (DPN) [poster]
No abstract available
Results from a randomized, controlled trial on efficacy and tolerability of a 5% Lidocaine-Medicated Plaster vs. Pregabalin in patients with Post-Herpetic Neuralgia (PHN) and Painful Diabetic Polyneuropathy (DPN) [poster]
No abstract available
Production and Analysis of Recycled Ammonium Perrhenate from CMSX-4 superalloys
The process to extract rhenium from a superalloy is an immense technical challenge due the complex chemistry involved. Being one of the rarest elements in the earth’s crust the scarcity and cost of rhenium makes it advantageous to recover the element from scrap superalloy. In this research the separation and monitoring of the different stages of the recycling process to extract rhenium from CMSX-4 superalloys using a distillation process were performed. This novel method combining distillation and use of exchange resins was used to separate rhenium from a complex mixture of metals in the CMSX-4 superalloy. The identification and quantitation of perrhenate and contaminants were performed by atomic absorption spectroscopy (AAS), Fourier transform infrared spectroscopy (FTIR), ion chromatography (IC) and Scanning Electron Microscopy- Energy Dispersive X-Ray (SEM-EDX). Perrhenate ions were extracted with purity close to 93%. The analytical characteristics for a novel infrared method to quickly identify perrhenate anions from CMSX-4 are presented. The main characteristics of the analytical validation were: LoD: 0.5% w/w; LoQ: 1.5% w/w; linear range 1.5-100% w/w; correlation coefficient R2 = 0.9905; precision (%RSD) for 10%w/w = 6.6 and 75%w/w = 4.1, respectively; accuracy (%) for 10% w/w 99.6% and 75% w/w=101.1, respectively
An investigation of Digoxin by Cyclic Voltammetry using Gold and Silver Solid Electrodes and Chemometric Analysis
Digoxin, one of the main cardiac glycosides medication, has shown to have a strong analytical response under investigation by voltammetric analysis using mercury electrodes, achieving nanomole sensitivity. In this study we investigated the suitability of solid electrodes as gold and silver electrodes in voltammetric analysis of this active pharmaceutical ingredient. The scope of the investigation was to evaluate if the use of these solid electrodes, more practical and especially less dangerous, under an operative and environmental aspects could represent a valid further possibility to add to the use of the mercury ones. Both of the solid electrodes have been tested at different pH of 5, 7.4, 10, and 11. PCA analysis has been performed and specific responses achieved. Micromole sensitivity has been achieved for both of the electrodes, showing that the use of these sensors could represent a preliminary analytical approach when the more accurate alternative choice is not necessary, being more practical and less environmental impacting than using mercury
Unitarized Chiral Perturbation Theory in a finite volume: scalar meson sector
We develop a scheme for the extraction of the properties of the scalar mesons
f0(600), f0(980), and a0(980) from lattice QCD data. This scheme is based on a
two-channel chiral unitary approach with fully relativistic propagators in a
finite volume. In order to discuss the feasibility of finding the mass and
width of the scalar resonances, we analyze synthetic lattice data with a fixed
error assigned, and show that the framework can be indeed used for an accurate
determination of resonance pole positions in the multi-channel scattering.Comment: 15 pages, 17 figure
POLG1 mutations and stroke like episodes : a distinct clinical entity rather than an atypical MELAS syndrome
POLG1 mutations have been associated with MELAS-like phenotypes. However given several clinical differences it is unknown whether POLG1 mutations are possible causes of MELAS or give raise to a distinct clinical and genetic entity, named POLG1-associated encephalopathy.Case presentation: We describe a 74 years old man carrying POLG1 mutations presenting with strokes, myopathy and ragged red fibers with some atypical aspects for MELAS such as late onset, lack of cerebral calcification and presence of frontal and occipital MRI lesions better consistent with the POLG associated-encephalopathy spectrum.
Conclusion: The lack of available data hampers a definite diagnosis in our patient as well as makes it difficult to compare MELAS, which is a clearly defined clinical syndrome, with POLG1-associated encephalopathy, which is so far a purely molecularly defined syndrome with a quite heterogeneous clinical picture. However, the present report contributes to expand the phenotypic spectrum of POLG1 mutations underlining the importance of searching POLG1 mutations in patients with mitochondrial signs and MELAS like phenotypes but negative for common mtDNA mutations
Observing the First Stars and Black Holes
The high sensitivity of JWST will open a new window on the end of the
cosmological dark ages. Small stellar clusters, with a stellar mass of several
10^6 M_sun, and low-mass black holes (BHs), with a mass of several 10^5 M_sun
should be directly detectable out to redshift z=10, and individual supernovae
(SNe) and gamma ray burst (GRB) afterglows are bright enough to be visible
beyond this redshift. Dense primordial gas, in the process of collapsing from
large scales to form protogalaxies, may also be possible to image through
diffuse recombination line emission, possibly even before stars or BHs are
formed. In this article, I discuss the key physical processes that are expected
to have determined the sizes of the first star-clusters and black holes, and
the prospect of studying these objects by direct detections with JWST and with
other instruments. The direct light emitted by the very first stellar clusters
and intermediate-mass black holes at z>10 will likely fall below JWST's
detection threshold. However, JWST could reveal a decline at the faint-end of
the high-redshift luminosity function, and thereby shed light on radiative and
other feedback effects that operate at these early epochs. JWST will also have
the sensitivity to detect individual SNe from beyond z=10. In a dedicated
survey lasting for several weeks, thousands of SNe could be detected at z>6,
with a redshift distribution extending to the formation of the very first stars
at z>15. Using these SNe as tracers may be the only method to map out the
earliest stages of the cosmic star-formation history. Finally, we point out
that studying the earliest objects at high redshift will also offer a new
window on the primordial power spectrum, on 100 times smaller scales than
probed by current large-scale structure data.Comment: Invited contribution to "Astrophysics in the Next Decade: JWST and
Concurrent Facilities", Astrophysics & Space Science Library, Eds. H.
Thronson, A. Tielens, M. Stiavelli, Springer: Dordrecht (2008
Neoglycoconjugates Derived from Deoxynojirimycin as Possible Therapeutic Agents for Cystic Fibrosis Lung Disease, by Modulation of the Sphingolipid Metabolism
The identification and development of novel and more efficient anti-inflammatory drugs for management of Cystic Fibrosis (CF) airway disease remains a
compelling need. Sphingolipids (SLs) play an important regulatory role in CF due to their function in pulmonary infections and inflammation. Given the emerging
importance of SLs in much pathology, novel drugs are continuously developed to selectively target different enzymes involved in SL metabolism. Iminosugars
disclose offer exciting and innovative opportunities for therapeutic agent discovery. Miglustat, the most popular iminosugar, has an anti-inflammatory effect
in CF models through inhibiting non-lysosomal-\u3b2-glucosidase 2 (GBA2). A small library of neoglycoconjugates with an adamantane mojety (AMP-DNJ),
characterized by differences in the length of the alkyl chain between the iminosugar and AMP, has been synthesized from the lead iminosugar deoxynojirimycin
(DNJ) (Ardes-Guisot, 2011). This study was hence aimed to test the effect of these AMP-DNJ derivatives on the inflammatory response to P. aeruginosa in CF
bronchial epithelial cells. Our original findings demonstrate that these AMP-DNJ derivatives reduce IL-8 mRNA expression in CF bronchial cells infected by
P. aeruginosa at nanomolar concentrations. The selectivity towards \u3b2 glucosidase seems to be modulated by variation of the length of the chain linking the
iminosugar and AMP, which are key motifs for the therapeutic activity of these compounds. Our results further support the use of SL metabolism modulators
for treating CF lung inflammation, thus providing useful hints on relevant targets and chemical structures that may be regarded as starting points for a drug
discovery campaign
The effect of age on DNA methylation in whole blood among Bangladeshi men and women
Background: It is well-known that methylation changes occur as humans age, however, understanding how age-related changes in DNA methylation vary by sex is lacking. In this study, we characterize the effect of age on DNA methylation in a sex-specific manner and determine if these effects vary by genomic context. We used the Illumina HumanMethylation 450 K array and DNA derived from whole blood for 400 adult participants (189 males and 211 females) from Bangladesh to identify age-associated CpG sites and regions and characterize the location of these age-associated sites with respect to CpG islands (vs. shore, shelf, or open sea) and gene regions (vs. intergenic). We conducted a genome-wide search for age-associated CpG sites (among 423,604 sites) using a reference-free approach to adjust for cell type composition (the R package RefFreeEWAS) and performed an independent replication analysis of age-associated CpGs. Results: The number of age-associated CpGs (p < 5 x 10-8) were 986 among men and 3479 among women of which 2027(63.8%) and 572 (64.1%) replicated (using Bonferroni adjusted p < 1.2 × 10-5). For both sexes, age-associated CpG sites were more likely to be hyper-methylated with increasing age (compared to hypo-methylated) and were enriched in CpG islands and promoter regions compared with other locations and all CpGs on the array. Although we observed strong correlation between chronological age and previously-developed epigenetic age models (r ≈ 0.8), among our top (based on lowest p-value) age-associated CpG sites only 12 for males and 44 for females are included in these prediction models, and the median chronological age compared to predicted age was 44 vs. 51.7 in males and 45 vs. 52.1 in females. Conclusions: Our results describe genome-wide features of age-related changes in DNA methylation. The observed associations between age and methylation were generally consistent for both sexes, although the associations tended to be stronger among women. Our population may have unique age-related methylation changes that are not captured in the established methylation-based age prediction model we used, which was developed to be non-tissue-specific
Rapid and highly variable warming of lake surface waters around the globe
In this first worldwide synthesis of in situ and satellite-derived lake data, we find that lake summer surface water temperatures rose rapidly (global mean = 0.34°C decade−1) between 1985 and 2009. Our analyses show that surface water warming rates are dependent on combinations of climate and local characteristics, rather than just lake location, leading to the counterintuitive result that regional consistency in lake warming is the exception, rather than the rule. The most rapidly warming lakes are widely geographically distributed, and their warming is associated with interactions among different climatic factors—from seasonally ice-covered lakes in areas where temperature and solar radiation are increasing while cloud cover is diminishing (0.72°C decade−1) to ice-free lakes experiencing increases in air temperature and solar radiation (0.53°C decade−1). The pervasive and rapid warming observed here signals the urgent need to incorporate climate impacts into vulnerability assessments and adaptation efforts for lakes.Peer reviewe
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