Ocular sarcoidosis and tuberculous lymphadenopathy: coincidence or real association

Tuberculosis and sarcoidosis share similarity in histopathologic findings and clinically occur in association with each other occasionally. Tuberculosis should always be ruled out before the diagnosis of sarcoidosis. But, the diagnosis is often complicated, especially in extrapulmonary cases. Here we present a case of bilateral vitreous hemorrhage with uveitis. Ocular sarcoidosis was initially diagnosed based on the characteristic ocular findings, negative results on chest radiography, tuberculosis culture, and polymerase chain reaction of aqueous, as well as simultaneous presence of panda and lambda sign on gallium-67 scans. The ocular condition improved after pars plana vitrectomy and systemic steroid therapy. However, TB lymphadenopathy but no recurrent ocular inflammation was found 6 years later. The patient received anti-TB treatment for 6 months thereafter. The eyes remained silent except cataract progression and glaucoma under two medications during this period. In conclusion, TB could occur coincidently or in association with sarcoidosis, continued follow-up is important for patients with ocular sarcoidosis

Effect of gamified perceptual learning on visual detection and discrimination skills in equine gait assessment

Background Visual assessment of equine lameness is an everyday veterinary task suffering from poor diagnostic accuracy. The aim of this study was to quantify the impact of the perceptual learning game ‘LamenessTrainer’ on skill development. Methods Thirty‐six undergraduate veterinary students engaged in four game modules teaching the assessment of fore‐ and hindlimb lameness. Computer animations of horses in this game displayed 0% (sound) to 70% (moderately lame) vertical movement asymmetry of head and pelvis. Performance, learning effects, diagnostic accuracy, detection thresholds and survey responses were analysed. Results Following staircase learning, more than 80% of students reliably classified horses with ≥20% asymmetry for forelimb lameness, ≥40% asymmetry for simplified hindlimb lameness and ≥50% asymmetry for realistic hindlimb lameness. During random presentation, on average 82% of sound and 65% of lame horses were assessed correctly during forelimb lameness evaluation, dropping to 39% of sound and 56% of lame horses for hindlimb lameness. Conclusion In less than two hours, systematic perceptual learning through deliberate practice can develop visual assessment skills to an accuracy level comparable to expert assessors scoring the same animations. Skills should be developed further to improve misclassifications of sound and mildly lame horses, especially for hindlimb lameness evaluation

Acyclovir for treating varicella in otherwise healthy children and adolescents: a systematic review of randomised controlled trials

BACKGROUND: Acyclovir has the potential to shorten the course of chickenpox which may result in reduced costs and morbidity. We conducted a systematic review of randomised controlled trials that evaluated acyclovir for the treatment of chickenpox in otherwise healthy children. METHODS: MEDLINE, EMBASE, and the Cochrane Library were searched. The reference lists of relevant articles were examined and primary authors and Glaxo Wellcome were contacted to identify additional trials. Two reviewers independently screened studies for inclusion, assessed study quality using the Jadad scale and allocation concealment, and extracted data. Continuous data were converted to a weighted mean difference (WMD). Overall estimates were not calculated due to differences in the age groups studied. RESULTS: Three studies were included. Methodological quality was 3 (n = 2) and 4 (n = 1) on the Jadad scale. Acyclovir was associated with a significant reduction in the number of days with fever, from -1.0 (95% CI -1.5,-0.5) to -1.3 (95% CI -2.0,-0.6). Results were inconsistent with respect to the number of days to no new lesions, the maximum number of lesions and relief of pruritis. There were no clinically important differences between acyclovir and placebo with respect to complications or adverse effects. CONCLUSION: Acyclovir appears to be effective in reducing the number of days with fever among otherwise healthy children with chickenpox. The results were inconsistent with respect to the number of days to no new lesions, the maximum number of lesions and the relief of itchiness. The clinical importance of acyclovir treatment in otherwise healthy children remains controversial

Nonlinear mixed effects modeling of gametocyte carriage in patients with uncomplicated malaria

<p>Abstract</p> <p>Background</p> <p>Gametocytes are the sexual form of the malaria parasite and the main agents of transmission. While there are several factors that influence host infectivity, the density of gametocytes appears to be the best single measure that is related to the human host's infectivity to mosquitoes. Despite the obviously important role that gametocytes play in the transmission of malaria and spread of anti-malarial resistance, it is common to estimate gametocyte carriage indirectly based on asexual parasite measurements. The objective of this research was to directly model observed gametocyte densities over time, during the primary infection.</p> <p>Methods</p> <p>Of 447 patients enrolled in sulphadoxine-pyrimethamine therapeutic efficacy studies in South Africa and Mozambique, a subset of 103 patients who had no gametocytes pre-treatment and who had at least three non-zero gametocyte densities over the 42-day follow up period were included in this analysis.</p> <p>Results</p> <p>A variety of different functions were examined. A modified version of the critical exponential function was selected for the final model given its robustness across different datasets and its flexibility in assuming a variety of different shapes. Age, site, initial asexual parasite density (logged to the base 10), and an empirical patient category were the co-variates that were found to improve the model.</p> <p>Conclusions</p> <p>A population nonlinear modeling approach seems promising and produced a flexible function whose estimates were stable across various different datasets. Surprisingly, dihydrofolate reductase and dihydropteroate synthetase mutation prevalence did not enter the model. This is probably related to a lack of power (quintuple mutations n = 12), and informative censoring; treatment failures were withdrawn from the study and given rescue treatment, usually prior to completion of follow up.</p

New insight into kinetics behavor of the structural formation process in Agar gelation

A time-resolved experimental study on the kinetics and relaxation of the structural formation process in gelling Agar-water solutions was carried out using our custom-built torsion resonator. The study was based on measurements of three naturally cooled solutions with agar concentrations of 0.75%, 1.0% and 2.0% w/w. It was found that the natural-cooling agar gelation process could be divided into three stages, sol stage (Stage I), gelation zone (Stage II) and gel stage (Stage III), based on the time/temperature evolutions of the structural development rate (SDR). An interesting fluctuant decaying behavior of SDR was observed in Stage II and III, indicative of a sum of multiple relaxation processes and well described by a multiple-order Gaussisn-like equation: . More interestingly, the temperature dependences of the fitted values of Wn in Stage II and Stage III were found to follow the different Arrhenius laws, with different activation energies of EaII= 39-74 KJ/mol and EaIII~7.0 KJ/mol. The two different Arrhenius-like behaviors respectively suggest that dispersions in Stage II be attributed to the relaxation of the self-assembly of agar molecules or the growth of junction zones en route to gelation, in which the formation or fission of hydrogen bonding interactions plays an important role; and that dispersions in Stage III be attributed to the relaxation dynamics of water released from various size domains close to the domain of the viscous flow of water during the syneresis process.Comment: 24 pages, 4 figures, 1 tabl

Bcl-2 protein family: Implications in vascular apoptosis and atherosclerosis

Apoptosis has been recognized as a central component in the pathogenesis of atherosclerosis, in addition to the other human pathologies such as cancer and diabetes. The pathophysiology of atherosclerosis is complex, involving both apoptosis and proliferation at different phases of its progression. Oxidative modification of lipids and inflammation differentially regulate the apoptotic and proliferative responses of vascular cells during progression of the atherosclerotic lesion. Bcl-2 proteins act as the major regulators of extrinsic and intrinsic apoptosis signalling pathways and more recently it has become evident that they mediate the apoptotic response of vascular cells in response to oxidation and inflammation either in a provocative or an inhibitory mode of action. Here we address Bcl-2 proteins as major therapeutic targets for the treatment of atherosclerosis and underscore the need for the novel preventive and therapeutic interventions against atherosclerosis, which should be designed in the light of molecular mechanisms regulating apoptosis of vascular cells in atherosclerotic lesions

Cerenkov Radiation Energy Transfer (CRET) Imaging: A Novel Method for Optical Imaging of PET Isotopes in Biological Systems

Positron emission tomography (PET) allows sensitive, non-invasive analysis of the distribution of radiopharmaceutical tracers labeled with positron (β(+))-emitting radionuclides in small animals and humans. Upon β(+) decay, the initial velocity of high-energy β(+) particles can momentarily exceed the speed of light in tissue, producing Cerenkov radiation that is detectable by optical imaging, but is highly absorbed in living organisms.To improve optical imaging of Cerenkov radiation in biological systems, we demonstrate that Cerenkov radiation from decay of the PET isotopes (64)Cu and (18)F can be spectrally coupled by energy transfer to high Stokes-shift quantum nanoparticles (Qtracker705) to produce highly red-shifted photonic emissions. Efficient energy transfer was not detected with (99m)Tc, a predominantly γ-emitting isotope. Similar to bioluminescence resonance energy transfer (BRET) and fluorescence resonance energy transfer (FRET), herein we define the Cerenkov radiation energy transfer (CRET) ratio as the normalized quotient of light detected within a spectral window centered on the fluorophore emission divided by light detected within a spectral window of the Cerenkov radiation emission to quantify imaging signals. Optical images of solutions containing Qtracker705 nanoparticles and [(18)F]FDG showed CRET ratios in vitro as high as 8.8±1.1, while images of mice with subcutaneous pseudotumors impregnated with Qtracker705 following intravenous injection of [(18)F]FDG showed CRET ratios in vivo as high as 3.5±0.3.Quantitative CRET imaging may afford a variety of novel optical imaging applications and activation strategies for PET radiopharmaceuticals and other isotopes in biomaterials, tissues and live animals

Is Canada ready for patient accessible electronic health records? A national scan

<p>Abstract</p> <p>Background</p> <p>Access to personal health information through the electronic health record (EHR) is an innovative means to enable people to be active participants in their own health care. Currently this is not an available option for consumers of health. The absence of a key technology, the EHR, is a significant obstacle to providing patient accessible electronic records. To assess the readiness for the implementation and adoption of EHRs in Canada, a national scan was conducted to determine organizational readiness and willingness for patient accessible electronic records.</p> <p>Methods</p> <p>A survey was conducted of Chief Executive Officers (CEOs) of Canadian public and acute care hospitals.</p> <p>Results</p> <p>Two hundred thirteen emails were sent to CEOs of Canadian general and acute care hospitals, with a 39% response rate. Over half (54.2%) of hospitals had some sort of EHR, but few had a record that was predominately electronic. Financial resources were identified as the most important barrier to providing patients access to their EHR and there was a divergence in perceptions from healthcare providers and what they thought patients would want in terms of access to the EHR, with providers being less willing to provide access and patients desire for greater access to the full record.</p> <p>Conclusion</p> <p>As the use of EHRs becomes more commonplace, organizations should explore the possibility of responding to patient needs for clinical information by providing access to their EHR. The best way to achieve this is still being debated.</p

Does zero temperature decide on the nature of the electroweak phase transition?

Taking on a new perspective of the electroweak phase transition, we investigate in detail the role played by the depth of the electroweak minimum (“vacuum energy difference”). We find a strong correlation between the vacuum energy difference and the strength of the phase transition. This correlation only breaks down if a negative eigen-value develops upon thermal corrections in the squared scalar mass matrix in the broken vacuum before the critical temperature. As a result the scalar fields slide across field space toward the symmetric vacuum, often causing a significantly weakened phase transition. Phenomenological constraints are found to strongly disfavour such sliding scalar scenarios. For several popular models, we suggest numerical bounds that guarantee a strong first order electroweak phase transition. The zero temperature phenomenology can then be studied in these parameter regions without the need for any finite temperature calculations. For almost all non-supersymmetric models with phenomenologically viable parameter points, we find a strong phase transition is guaranteed if the vacuum energy difference is greater than −8.8 × 107 GeV4. For the GNMSSM, we guarantee a strong phase transition for phenomenologically viable parameter points if the vacuum energy difference is greater than −6.9×107 GeV4. Alternatively, we capture more of the parameter space exhibiting a strong phase transition if we impose a simultaneous bound on the vacuum energy difference and the singlet mass

Towards Electrosynthesis in Shewanella: Energetics of Reversing the Mtr Pathway for Reductive Metabolism

Bioelectrochemical systems rely on microorganisms to link complex oxidation/reduction reactions to electrodes. For example, in Shewanella oneidensis strain MR-1, an electron transfer conduit consisting of cytochromes and structural proteins, known as the Mtr respiratory pathway, catalyzes electron flow from cytoplasmic oxidative reactions to electrodes. Reversing this electron flow to drive microbial reductive metabolism offers a possible route for electrosynthesis of high value fuels and chemicals. We examined electron flow from electrodes into Shewanella to determine the feasibility of this process, the molecular components of reductive electron flow, and what driving forces were required. Addition of fumarate to a film of S. oneidensis adhering to a graphite electrode poised at −0.36 V versus standard hydrogen electrode (SHE) immediately led to electron uptake, while a mutant lacking the periplasmic fumarate reductase FccA was unable to utilize electrodes for fumarate reduction. Deletion of the gene encoding the outer membrane cytochrome-anchoring protein MtrB eliminated 88% of fumarate reduction. A mutant lacking the periplasmic cytochrome MtrA demonstrated more severe defects. Surprisingly, disruption of menC, which prevents menaquinone biosynthesis, eliminated 85% of electron flux. Deletion of the gene encoding the quinone-linked cytochrome CymA had a similar negative effect, which showed that electrons primarily flowed from outer membrane cytochromes into the quinone pool, and back to periplasmic FccA. Soluble redox mediators only partially restored electron transfer in mutants, suggesting that soluble shuttles could not replace periplasmic protein-protein interactions. This work demonstrates that the Mtr pathway can power reductive reactions, shows this conduit is functionally reversible, and provides new evidence for distinct CymA:MtrA and CymA:FccA respiratory units