678 research outputs found
Hairy Leukoplakia
Oral hairy leukoplakia (OHL) is a disease of the mucosa first described in 1984. This pathology is associated with Epstein-Barr virus (EBV) and occurs mostly in people with HIV infection, both immunocompromised and immunocompetent, and can affect patients who are HIV negative. [1, 2] The first case in an HIV-negative patient was reported in 1999 in a 56-year-old patient with acute lymphocytic leukemia. Later, many cases were reported in heart, kidney, and bone marrow transplant recipients and patients with hematological malignancies. [3, 4
Racial Differences by Ischemic Stroke Subtype: A Comprehensive Diagnostic Approach
Background. Previous studies have suggested that black populations have more small-vessel and fewer cardioembolic strokes. We sought to analyze racial differences in ischemic stroke subtype employing a comprehensive diagnostic workup with magnetic resonance-imaging-(MRI-) based evaluation including diffusion-weighted imaging (DWI).
Methods. 350 acute ischemic stroke patients admitted to an urban hospital with standardized comprehensive diagnostic evaluations were retrospectively analyzed. Ischemic stroke subtype was determined by three Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification systems. Results. We found similar proportions of cardioembolic and lacunar strokes in the black and white cohort. The only subtype category with a significant difference by race was āstroke of other etiology,ā more common in whites. Black stroke patients were more likely to have an incomplete evaluation, but this did not reach significance. Conclusions. We found similar proportions by race of cardioembolic and lacunar strokes when employing a full diagnostic evaluation including DWI MRI. The relatively high rate of cardioembolism may have been underappreciated in black stroke patients when employing a CT approach to stroke subtype diagnosis. Further research is required to better understand the racial differences in frequency of āstroke of other etiologyā and explore disparities in the extent of diagnostic evaluations
Respiratory Muscle Paralysis Associated With Colistin, Polymyxin B, and Muscle Relaxants Drugs: A Case Report
Polymyxins B and E (colistin) exert a bactericidal effect on the gram-negative bacterial cell wall, causing permeability changes in the cytoplasmic membrane, leading to cell death. Their use was substantially decreased in clinical practice from the 1970s to 2000s due to their significant nephrotoxicity and neurotoxicity compared to the newly introduced antibiotics. The increasing prevalence of multidrug-resistant gram-negative bacteria infections in this century has led to an upsurge in the use of these āolderā drugs. Respiratory paralysis caused by neuromuscular blockage associated with the use of polymyxin B and E was reported mostly in literature published in the 1960s to 1970s with a few reports after 2000. In addition, such a reaction might be enhanced by the presence of other classes of drugs. We report a case of polymyxin B and Eāinduced apnea in a patient receiving āmuscle relaxants.
Multiple Inflation, Cosmic String Networks and the String Landscape
Motivated by the string landscape we examine scenarios for which inflation is
a two-step process, with a comparatively short inflationary epoch near the
string scale and a longer period at a much lower energy (like the TeV scale).
We quantify the number of -foldings of inflation which are required to yield
successful inflation within this picture. The constraints are very sensitive to
the equation of state during the epoch between the two inflationary periods, as
the extra-horizon modes can come back inside the horizon and become
reprocessed. We find that the number of -foldings during the first
inflationary epoch can be as small as 12, but only if the inter-inflationary
period is dominated by a network of cosmic strings (such as might be produced
if the initial inflationary period is due to the brane-antibrane mechanism). In
this case a further 20 -foldings of inflation would be required at lower
energies to solve the late universe's flatness and horizon problems.Comment: 27 pages, 6 figures; v2: refences adde
Resistance to quambalaria shoot blight and myrtle rust in Corymbia calophylla seedlings
Abstract Corymbia calophylla (marri), an endemic keystone tree species in southwest Western Australia, is increasingly impacted by the introduced basidiomycete smut Quambalaria pitereka. The basidiomycete rust Austropuccinia psidii (myrtle rust), an invasive pathogen recently introduced to Eastern Australia, is expected to spread to the southwest of Western Australia eventually. Austropuccinia psidii has similar epidemiology to Q. pitereka, and there is concern that C. calophylla may be susceptible. Preliminary pathogenicity tests showed significant differences in aggressiveness between twelve Q. pitereka isolates, and there was evidence of interactions between isolates and C. calophylla provenances. Seedlings from 59 open-pollinated families from 11 provenances covering the natural range of marri were screened for resistance to Q. pitereka and A. psidii under controlled glasshouse conditions. Resistance of seedlings within provenances to Q. pitereka and A. psidii differed significantly. There was no significant correlation between resistance to Q. pitereka and resistance to A. psidii. Seedlings of provenances from wetter regions were more resistant to both pathogens, but the correlation coefficients were insignificant. Seedlings of four families in three provenances (Serpentine, Chidlow, and Kingston) showed 100% resistance to Q. pitereka. Narrow-sense heritability estimates were 0.07 for quambalaria shoot blight resistance and 0.34 for myrtle rust resistance. The results indicate the potential to use selected families/individuals resistant to Q. pitereka and A. psidii for tree improvement programs and adaptive management strategies
Quambalaria shoot blight resistance in marri (Corymbia calophylla) : genetic parameters and correlations between growth rate and blight resistance
Quambalaria shoot blight (QSB) has emerged recently as a severe disease of Corymbia calophylla (marri). In this study, QSB
damage and growth were assessed in Corymbia calophylla trees at 4 and 6 years of age in two common gardens consisting
of 165 and 170 open-pollinated families representing 18 provenances across the speciesā natural distribution. There were
significant differences between provenances for all traits. The narrow-sense heritability for growth traits and QSB damage at
both sites were low to moderate. The genetic correlation between QSB damage and growth traits was negative; fast-growing
families were less damaged by QSB disease. Age-age genetic correlations for individual traits at four and six years were very
strong, and the type-B (siteāsite) correlations were strongly positive for all traits. Provenances from cooler wetter regions
showed higher resistance to QSB. The QSB incidence at 6 years was significantly correlated with environmental factors of
the provenanceās origin. The QSB incidence at years four and six was not correlated with the QSB expression in 3-month-old
seedlings. Based on these results, selection for resistance could be undertaken using 4-year-old trees. There is potential for
a resistance breeding program to develop populations of marri genetically diverse and resistant to QSB.Open Access funding by CAUL and its Member Institutions. PhD scholarship between the Vietnamese Government and Murdoch University as well as the Australian Research Council Linkage Program.https://link.springer.com/journal/11295am2023Forestry and Agricultural Biotechnology Institute (FABI)BiochemistryGeneticsMicrobiology and Plant Patholog
Constraints on Brane Inflation and Cosmic Strings
By considering simple, but representative, models of brane inflation from a
single brane-antibrane pair in the slow roll regime, we provide constraints on
the parameters of the theory imposed by measurements of the CMB anisotropies by
WMAP including a cosmic string component. We find that inclusion of the string
component is critical in constraining parameters. In the most general model
studied, which includes an inflaton mass term, as well as the brane-antibrane
attraction, values n_s < 1.02 are compatible with the data at 95 % confidence
level. We are also able to constrain the volume of internal manifold (modulo
factors dependent on the warp factor) and the value of the inflaton field to be
less than 0.66M_P at horizon exit. We also investigate models with a mass term.
These observational considerations suggest that such models have r < 2*10^-5,
which can only be circumvented in the fast roll regime, or by increasing the
number of antibranes. Such a value of r would not be detectable in CMB
polarization experiment likely in the near future, but the B-mode signal from
the cosmic strings could be detectable. We present forecasts of what a similar
analysis using PLANCK data would yield and find that it should be possible to
rule out G\mu > 6.5*10^-8 using just the TT, TE and EE power spectra.Comment: 11 pages, 3 figures, revtex4, typos corrected, references adde
High Rate of Microbleed Formation Following Primary Intracerebral Hemorrhage
Background
We sought to investigate the frequency of microbleed development following intracerebral hemorrhage in a predominantly African-American population and to identify predictors of new microbleed formation.
Aims and/or hypothesis
To investigate the frequency and predictors of new microbleeds following intracerebral hemorrhage.
Methods
The DECIPHER study was a prospective, longitudinal, magnetic resonance-based cohort study designed to evaluate racial/ethnic differences in risk factors for microbleeds and to evaluate the prognostic impact of microbleeds in this intracerebral hemorrhage population. We evaluated new microbleed formation in two time periods: from baseline to 30 days and from 30 days to year 1.
Results
Of 200 subjects enrolled in DECIPHER, 84 had magnetic resonance imaging at all required time points to meet criteria for this analysis. In the baseline to day 30 analysis, 11 (13Ā·1%) had new microbleeds, compared with 25 (29Ā·8%) in the day 30 to year 1 analysis. Logistic regression analysis demonstrated that baseline number of microbleeds [odds ratio 1Ā·05 (95% confidence interval 1Ā·01, 1Ā·08), Pā=ā0Ā·01] was associated with new microbleed formation at 30 days. A logistic regression model predicting new microbleed at one-year included baseline number of microbleeds [odds ratio 1Ā·05 (1Ā·00, 1Ā·11), Pā=ā0Ā·046], baseline age [odds ratio 1Ā·05 (1Ā·00, 1Ā·10), Pā=ā0Ā·04], and white matter disease score [odds ratio 1Ā·18 (0Ā·96, 1Ā·45). Pā=ā0Ā·115]. Overall, 28 of 84 (33Ā·3%) intracerebral hemorrhage subjects formed new microbleeds at some point in the first year post-intracerebral hemorrhage.
Conclusions
We found that one-third of intracerebral hemorrhage subjects in this cohort surviving one-year developed new microbleeds, which suggests a dynamic and rapidly progressive vasculopathy. Future studies are needed to examine the impact of new microbleed formation on patient outcomes
Primordial Black Holes, Eternal Inflation, and the Inflationary Parameter Space after WMAP5
We consider constraints on inflation driven by a single, minimally coupled
scalar field in the light of the WMAP5 dataset, as well as ACBAR and the
SuperNova Legacy Survey. We use the Slow Roll Reconstruction algorithm to
derive optimal constraints on the inflationary parameter space. The scale
dependence in the slope of the scalar spectrum permitted by WMAP5 is large
enough to lead to viable models where the small scale perturbations have a
substantial amplitude when extrapolated to the end of inflation. We find that
excluding parameter values which would cause the overproduction of primordial
black holes or even the onset of eternal inflation leads to potentially
significant constraints on the slow roll parameters. Finally, we present a more
sophisticated approach to including priors based on the total duration of
inflation, and discuss the resulting restrictions on the inflationary parameter
space.Comment: v2: version published in JCAP. Minor clarifications and references
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