Comparison of Newtonian and Non-newtonian Fluid Models in Blood Flow Simulation in Patients With Intracranial Arterial Stenosis

BACKGROUND: Newtonian fluid model has been commonly applied in simulating cerebral blood flow in intracranial atherosclerotic stenosis (ICAS) cases using computational fluid dynamics (CFD) modeling, while blood is a shear-thinning non-Newtonian fluid. We aimed to investigate the differences of cerebral hemodynamic metrics quantified in CFD models built with Newtonian and non-Newtonian fluid assumptions, in patients with ICAS. METHODS: We built a virtual artery model with an eccentric 75% stenosis and performed static CFD simulation. We also constructed CFD models in three patients with ICAS of different severities in the luminal stenosis. We performed static simulations on these models with Newtonian and two non-Newtonian (Casson and Carreau-Yasuda) fluid models. We also performed transient simulations on another patient-specific model. We measured translesional pressure ratio (PR) and wall shear stress (WSS) values in all CFD models, to reflect the changes in pressure and WSS across a stenotic lesion. In all the simulations, we compared the PR and WSS values in CFD models derived with Newtonian, Casson, and Carreau-Yasuda fluid assumptions. RESULTS: In all the static and transient simulations, the Newtonian/non-Newtonian difference on PR value was negligible. As to WSS, in static models (virtual and patient-specific), the rheological difference was not obvious in areas with high WSS, but observable in low WSS areas. In the transient model, the rheological difference of WSS areas with low WSS was enhanced, especially during diastolic period. CONCLUSION: Newtonian fluid model could be applicable for PR calculation, but caution needs to be taken when using the Newtonian assumption in simulating WSS especially in severe ICAS cases

Simvastatin inhibits TLR8 signaling in primary human monocytes and spontaneous TNF production from rheumatoid synovial membrane cultures

Simvastatin has been shown to have anti-inflammatory effects that are independent of its serum cholesterol lowering action, but the mechanisms by which these anti-inflammatory effects are mediated have not been elucidated. To explore the mechanism involved, the effect of simvastatin on Toll-like receptor (TLR) signalling in primary human monocytes was investigated. A short pre-treatment with simvastatin dose-dependently inhibited the production of tumor necrosis factor-α (TNF) in response to TLR8 (but not TLRs 2, 4, or 5) activation. Statins are known inhibitors of the cholesterol biosynthetic pathway, but intriguingly TLR8 inhibition could not be reversed by addition of mevalonate or geranylgeranyl pyrophosphate; downstream products of cholesterol biosynthesis. TLR8 signalling was examined in HEK 293 cells stably expressing TLR8, where simvastatin inhibited IKKα/β phosphorylation and subsequent NF-κB activation without affecting the pathway to AP-1. Since simvastatin has been reported to have anti-inflammatory effects in RA patients and TLR8 signalling contributes to TNF production in human RA synovial tissue in culture, simvastatin was tested in these cultures. Simvastatin significantly inhibited the spontaneous release of TNF in this model which was not reversed by mevalonate. Together, these results demonstrate a hitherto unrecognized mechanism of simvastatin inhibition of TLR8 signalling that may in part explain its beneficial anti-inflammatory effects

Higher media multi-tasking activity is associated with smaller gray-matter density in the anterior cingulate cortex

Media multitasking, or the concurrent consumption of multiple media forms, is increasingly prevalent in today’s society and has been associated with negative psychosocial and cognitive impacts. Individuals who engage in heavier media-multitasking are found to perform worse on cognitive control tasks and exhibit more socio-emotional difficulties. However, the neural processes associated with media multi-tasking remain unexplored. The present study investigated relationships between media multitasking activity and brain structure. Research has demonstrated that brain structure can be altered upon prolonged exposure to novel environments and experience. Thus, we expected differential engagements in media multitasking to correlate with brain structure variability. This was confirmed via Voxel-Based Morphometry (VBM) analyses: Individuals with higher Media Multitasking Index (MMI) scores had smaller gray matter density in the anterior cingulate cortex (ACC). Functional connectivity between this ACC region and the precuneus was negatively associated with MMI. Our findings suggest a possible structural correlate for the observed decreased cognitive control performance and socio-emotional regulation in heavy media-multitaskers. While the cross-sectional nature of our study does not allow us to specify the direction of causality, our results brought to light novel associations between individual media multitasking behaviors and ACC structure differences

The efficacy and safety of Yupingfeng Powder with variation in the treatment of allergic rhinitis: Study protocol for a randomized, double-blind, placebo-controlled trial

Background: Allergic rhinitis (AR) is an upper airways chronic inflammatory disease mediated by IgE, which affects 10%–20% of the population. The mainstay for allergic rhinitis nowadays include steroids and antihistamines, but their effects are less than ideal. Many patients therefore seek Chinese medicine for treatment and Yupingfeng Powder is one of the most common formulae prescribed. In this study, we aim to investigate the efficacy and safety of Yupingfeng Powder with variation for the treatment of allergic rhinitis.Study design: This is a double-blind, randomized, placebo-controlled trial. A 2-week screening period will be implemented, and then eligible subjects with allergic rhinitis will receive interventions of either “Yupingfeng Powder with variation” granules or placebo granules for 8 weeks, followed by post treatment visits at weeks 12 and 16. The change in the Total Nasal Symptom Score (TNSS) will be used as the primary outcome.Discussion: This trail will evaluate the efficacy and safety of Yupingfeng Powder in treating allergic rhinitis. The study may provide the solid evidence of Yupingfeng Powder with variation can produce better clinical efficacy than the placebo granules.Trial registration:ClinicalTrials.gov, identifier NCT04976023

Probing the Reactivity of the Ce=O Multiple Bond in a Cerium(IV) Oxo Complex

The reactivity of the cerium­(IV) oxo complex [(L_OEt)₂Ce^IV(O)­(H₂O)]·MeC­(O)­NH₂ (<b>1</b>; L_OEt^– = [CoCp­{P­(O)­(OEt)₂}₃]⁻, where Cp = η⁵-C₅H₅) toward electrophiles and Brønsted acids has been investigated. The treatment of <b>1</b> with acetic anhydride afforded the diacetate complex [Ce^IV(L_OEt)₂(O₂CMe)₂] (<b>2</b>). The reaction of <b>1</b> with B­(C₆F₅)₃ yielded [Ce^IV(L_OEt)₂(Me₂CONH₂)₂]­[B­(C₆F₅)₃(OH)]₂ (<b>3</b>), in which the [B­(C₆F₅)₃(OH)]⁻ anions are H-bonded to the O-bound acetamide ligands. The treatment of <b>1</b> with HCl and HNO₃ afforded [Ce^IV(L_OEt)₂Cl₂] and [Ce^IV(L_OEt)₂(NO₃)₂], respectively. Protonation of <b>1</b> with triflic acid (HOTf) gave the diaqua complex [Ce^IV(L_OEt)₂(H₂O)₂]­(OTf)₂ (<b>4</b>), in which the triflate anions are H-bonded to the two aqua ligands. The treatment of <b>1</b> with phenol afforded the phenoxide complex [Ce^IV(L_OEt)₂(OPh)₂] (<b>5</b>). The oxo-bridged bimetallic complex [(L_OEt)₂(Me₂CONH₂)­Ce^IV(O)­NaL_OEt] (<b>6</b>) with the Ce–O_oxo and Na–O_oxo distances of 1.953(4) and 2.341(4) Å, respectively, was obtained from the reaction of <b>1</b> with [NaL_OEt]. Density functional theory calculations showed that the model complex [(L_OMe)₂Ce^IV(Me₂CONH₂)­(O)­NaL_OMe] (<b>6A</b>; L_OMe^– = [CoCp­{P­(O)­(OMe)₂}₃]⁻) contains a polarized CeO multiple bond. The energy for dissociation of the {NaL_OMe} fragment from <b>6A</b> in acetonitrile was calculated to be +33.7 kcal/mol, which is higher than that for dissociation of the H-bonded acetamide from [(L_OMe)₂Ce^IV(O)­(H₂O)]·MeC­(O)­NH₂ (<b>1A</b>) (calculated to be +17.4 kcal/mol). In hexanes containing trace water, complex <b>1</b> decomposed readily to a mixture of a tetranuclear cerium­(IV) oxo cluster, [Ce^IV₄(L_OEt)₄(μ₄-O)­(μ₂-O)₄(μ₂-OH)₂] (<b>7</b>), and a cerium­(III) complex, [Ce^III(L_OEt)₂(H₂O)₂]­[L_OEt] [<b>8</b>(L_OEt)], whereas the cerium/sodium oxo complex <b>6</b> is stable under the same conditions. The crystal structures of <b>3</b>, <b>4</b>·H₂O, <b>6</b>, and <b>8</b>(L_OEt) have been determined

Desired Chinese medicine practitioner capabilities and professional development needs: a survey of registered practitioners in Victoria, Australia

Background The State of Victoria in Australia introduced Chinese medicine practitioner registration in 2000 and issued its education guidelines in late 2002 for introduction in 2005. This study obtained practitioners&#039; views on desired capabilities for competent Chinese medicine practice and to identify professional development needs. Methods A questionnaire, consisting of 28 predefined capabilities in four categories with a rating scale of importance from one to five, was developed and sent to all registered Chinese medicine practitioners in the State of Victoria, Australia in October, 2005. Results Two hundreds and twenty eight completed questionnaires were returned which represented a response rate of 32.5%. Of the four categories of capabilities, technical capabilities were considered to be the most important for clinical practice. Specifically, the ability to perform acupuncture treatment and/or dispense an herbal prescription was ranked the highest. In contrast, research and information management capabilities were considered the least important. The educational background of practitioners appeared to be an important factor influencing their rating of capabilities. Significantly, nearly double the number of practitioners with Australian qualifications than practitioners trained overseas valued communication as an important capability. For continuing professional education, clinical skills courses were considered as a priority while research degree studies were not. Conclusion Registered Chinese medicine practitioners viewed skills training as important but did not support the need for research and information management training. This represents a significant hurdle to developing Chinese medicine as a form of evidence-based healthcare

ITGAM is associated with disease susceptibility and renal nephritis of systemic lupus erythematosus in Hong Kong Chinese and Thai

ITGAM was recently found to be associated with systemic lupus erythematosus (SLE) in populations of not only European ancestry, but also in Hispanic- and African-Americans, Mexicans and Colombians. The risk alleles in the gene, however, were found to be monomorphic in two Asian populations examined: Japanese and Korean. In this study, using a collection of 910 SLE patients and 2360 controls from Chinese living in Hong Kong, analyzed by both genome-wide association and direct sequencing, we confirmed the association of the same risk alleles in ITGAM with the disease. These findings were further replicated in the Thai population with 278 patients and 383 ethnicity- and geography-matched controls. Subphenotype stratification analyses showed significantly more involvement of the gene in patients with renal nephritis and neurological disorders. Although our results support a pivotal role by rs1143679 (R77H) in disease association, our data also suggests an additional contribution from rs1143683, another non-synonymous polymorphism in this gene (A858V). Therefore, despite the low-allele frequencies of the risk alleles of the gene in our two Asian populations, ITGAM was confirmed to be a risk factor related to disease susceptibility and probably severe manifestations of SLE

Delay in diagnosis of tuberculosis in Rawalpindi, Pakistan

<p>Abstract</p> <p>Background</p> <p>Delay in diagnosis and treatment of tuberculosis (TB) may enhance the chances of morbidity and mortality and play a key role in continuous transmission of the bacilli. The objective of this study was to describe health care seeking behavior of suspected TB patients and initial diagnostic work up prior to consultation and diagnosis at National TB Center (NTC).</p> <p>Findings</p> <p>Interviews of 252 sputum smear positive patients were taken from NTC, Rawalpindi. The duration between on-set of symptoms and start of treatment was considered as the total delay and correlated with general characteristics of TB patients. The proportion of males and females were 49.6% and 50.4% with median age of 25 and 24 years respectively. A median delay of 56 days (8 weeks) was observed which was significantly associated with age, cough and fever. More than 50% of the current patients had a history of contact with previously diagnosed TB patients. The majority of patients (63%) visited health care providers within three weeks of appearance of symptoms but only thirty five percent were investigated for TB diagnosis.</p> <p>Conclusion</p> <p>Cough and fever are being ignored as likely symptoms of TB by patients as well as health care providers resulting in delay. Engaging private practitioners through public private mix (PPM) approach for expansion of TB diagnosis and increasing public awareness could be more beneficial to reduce delay.</p

Non-invasive intravital imaging of cellular differentiation with a bright red-excitable fluorescent protein

A method for non-invasive visualization of genetically labelled cells in animal disease models with micron-level resolution would greatly facilitate development of cell-based therapies. Imaging of fluorescent proteins (FPs) using red excitation light in the “optical window” above 600 nm is one potential method for visualizing implanted cells. However, previous efforts to engineer FPs with peak excitation beyond 600 nm have resulted in undesirable reductions in brightness. Here we report three new red-excitable monomeric FPs obtained by structure-guided mutagenesis of mNeptune, previously the brightest monomeric FP when excited beyond 600 nm. Two of these, mNeptune2 and mNeptune2.5, demonstrate improved maturation and brighter fluorescence, while the third, mCardinal, has a red-shifted excitation spectrum without reduction in brightness. We show that mCardinal can be used to non-invasively and longitudinally visualize the differentiation of myoblasts and stem cells into myocytes in living mice with high anatomical detail