2,659 research outputs found
The relationship between the COPD Assessment Test score and airflow limitation in Japan in patients aged over 40 years with a smoking history.
BACKGROUND: A large number of chronic obstructive pulmonary disease (COPD) patients in Japan remain undiagnosed, primarily due to the underuse of spirometry. Two studies were conducted to see whether the COPD Assessment Test (CAT) in primary care has the potential to identify those patients who need spirometry for a diagnosis of COPD and to determine whether patients with cardiovascular disease had airflow limitation, which could be detected by CAT.
MATERIALS AND METHODS: Two multicenter, noninterventional, prospective studies (studies 1 and 2) were conducted across Japan. Patients in both studies were ≥40 years old with a smoking history. Those in study 1 were seen in primary care and had experienced repeated respiratory tract infections, but had no diagnosis of COPD. Patients in study 2 were identified in cardiovascular disease clinics when routinely visiting for their cardiovascular disease. All patients completed the CAT prior to lung-function testing by hand-held spirometry. The presence of airflow limitation was defined as a forced expiratory volume in 1 second (FEV1)/FEV6 ratio<0.73.
RESULTS: A total of 3,062 subjects completed the CAT (2,067 in study 1, 995 in study 2); 88.8% were male, and the mean age (±standard deviation) was 61.5±11.6 years. Airflow limitation was found in 400 (19.4%) patients in study 1, and 269 (27.0%) in study 2. The CAT score in patients with airflow limitation was significantly higher than in patients without airflow limitation in both studies: 8.6 (95% confidence interval [CI] 7.9-9.2) versus 7.4 (95% CI 7.1-7.6) in study 1, and 8.3 (95% CI 7.5-9.2) versus 6.4 (95% CI 6.0-6.8) in study 2 (both P<0.001).
CONCLUSION: These findings suggest that the CAT has the potential to identify patients with cardiovascular disease or a history of frequent chest infections who need spirometry to diagnose COPD
Life and Death at the Edge of a Windy Cliff
The survival probability of a particle diffusing in the two dimensional
domain near a ``windy cliff'' at is investigated. The particle dies
upon reaching the edge of the cliff. In addition to diffusion, the particle is
influenced by a steady ``wind shear'' with velocity , \ie, no average bias either toward or away from the cliff.
For this semi-infinite system, the particle survival probability decays with
time as , compared to in the absence of wind. Scaling
descriptions are developed to elucidate this behavior, as well as the survival
probability within a semi-infinite strip of finite width with particle
absorption at . The behavior in the strip geometry can be described in
terms of Taylor diffusion, an approach which accounts for the crossover to the
decay when the width of the strip diverges. Supporting numerical
simulations of our analytical results are presented.Comment: 13 pages, plain TeX, 5 figures available upon request to SR
(submitted to J. Stat. Phys.
Aberrant Disgust Responses and Immune Reactivity in Cocaine-Dependent Men
Background: Infectious diseases are the most common and cost-intensive health complications associated with drug addiction. There is wide belief that drug-dependent individuals expose themselves more regularly to disease-related pathogens through risky behaviors such as sharing pipes and needles, thereby increasing their risk for contracting an infectious disease. However, evidence is emerging indicating that not only lifestyle but also the immunomodulatory effects of addictive drugs, such as cocaine, may account for their high infection risk. As feelings of disgust are thought to be an important psychological mechanism in avoiding the exposure to pathogens, we sought to investigate behavioral, physiological, and immune responses to disgust-evoking cues in both cocaine-dependent and healthy men.
Methods: All participants (N = 61) were exposed to neutral and disgust-evoking photographs depicting food and nonfood images while response accuracy, latency, and skin conductivity were recorded. Saliva samples were collected before and after exposure to neutral and disgusting images, respectively. Attitudes toward disgust and hygiene behaviors were assessed using questionnaire measures.
Results: Response times to disgust-evoking photographs were prolonged in all participants, and specifically in cocaine-dependent individuals. While viewing the disgusting images, cocaine-dependent individuals exhibited aberrant skin conductivity and increased the secretion of the salivary cytokine interleukin-6 relative to control participants.
Conclusion: Our data provide evidence of a hypersensitivity to disgusting stimuli in cocaine-dependent individuals, possibly reflecting conditioned responses to noningestive sources of infection. Coupled with a lack of interoception of bodily signals, aberrant disgust responses might lead to increased infection susceptibility in affected individuals
Spiral Motion in a Noisy Complex Ginzburg-Landau Equation
The response of spiral waves to external perturbations in a stable regime of
the two-dimensional complex Ginzburg-Landau equation (CGLE) is investigated. It
is shown that the spiral core has a finite mobility and performs Brownian
motion when driven by white noise. Combined with simulation results, this
suggests that defect-free and quasi-frozen states in the noiseless CGLE are
unstable against free vortex excitation at any non-zero noise strength.Comment: RevTex, 4 pages, 3 figures, submitted to Phys. Rev. Let
Praziquantel: its use in control of schistosomiasis in sub-Saharan Africa and current research needs
Treatment with praziquantel (PZQ) has become virtually the sole basis of schistosomiasis control in sub-Saharan Africa and elsewhere, and the drug is reviewed here in the context of the increasing rate that it is being used for this purpose. Attention is drawn to our relative lack of knowledge about the mechanisms of action of PZQ at the molecular level, the need for more work to be done on schistosome isolates that have been collected recently from endemic areas rather than those maintained in laboratory conditions for long periods, and our reliance for experimental work mainly on Schistosoma mansoni, little work having been done on S. haematobium. There is no evidence that resistance to PZQ has been induced in African schistosomes as a result of its large-scale use on that continent to date, but there is also no assurance that PZQ and/or schistosomes are in any way unique and that resistant organisms will not be selected as a result of widespread drug usage. The failure of PZQ to produce complete cures in populations given a routine treatment should therefore solicit considerable concern. With few alternatives to PZQ currently available and/or on the horizon, methods to monitor drug-susceptibility in African schistosomes need to be devised and used to help ensure that this drug remains effective for as long a time as possibl
Akt substrate TBC1D1 regulates GLUT1 expression through the mTOR pathway in 3T3-L1 adipocytes
Multiple studies have suggested that the protein kinase Akt/PKB (protein kinase B) is required for insulin-stimulated glucose transport in skeletal muscle and adipose cells. In an attempt to understand links between Akt activation and glucose transport regulation, we applied mass spectrometry-based proteomics and bioinformatics approaches to identify potential Akt substrates containing the phospho-Akt substrate motif RXRXXpS/T. The present study describes the identification of the Rab GAP (GTPase-activating protein)-domain containing protein TBC1D1 [TBC (Tre-2/Bub2/Cdc16) domain family, member 1], which is closely related to TBC1D4 [TBC domain family, member 4, also denoted AS160 (Akt substrate of 160 kDa)], as an Akt substrate that is phosphorylated at Thr(590). RNAi (RNA interference)-mediated silencing of TBC1D1 elevated basal deoxyglucose uptake by approx. 61% in 3T3-L1 mouse embryo adipocytes, while the suppression of TBC1D4 and RapGAP220 under the same conditions had little effect on basal and insulin-stimulated deoxyglucose uptake. Silencing of TBC1D1 strongly increased expression of the GLUT1 glucose transporter but not GLUT4 in cultured adipocytes, whereas the decrease in TBC1D4 had no effect. Remarkably, loss of TBC1D1 in 3T3-L1 adipocytes activated the mTOR (mammalian target of rapamycin)-p70 S6 protein kinase pathway, and the increase in GLUT1 expression in the cells treated with TBC1D1 siRNA (small interfering RNA) was blocked by the mTOR inhibitor rapamycin. Furthermore, overexpression of the mutant TBC1D1-T590A, lacking the putative Akt/PKB phosphorylation site, inhibited insulin stimulation of p70 S6 kinase phosphorylation at Thr(389), a phosphorylation induced by mTOR. Taken together, our data suggest that TBC1D1 may be involved in controlling GLUT1 glucose transporter expression through the mTOR-p70 S6 kinase pathway
Vortex Dynamics in Dissipative Systems
We derive the exact equation of motion for a vortex in two- and three-
dimensional non-relativistic systems governed by the Ginzburg-Landau equation
with complex coefficients. The velocity is given in terms of local gradients of
the magnitude and phase of the complex field and is exact also for arbitrarily
small inter-vortex distances. The results for vortices in a superfluid or a
superconductor are recovered.Comment: revtex, 5 pages, 1 encapsulated postscript figure (included), uses
aps.sty, epsf.te
Aberrant Disgust Responses and Immune Reactivity in Cocaine-Dependent Men
Background: Infectious diseases are the most common and cost-intensive health complications associated with drug addiction. There is wide belief that drug-dependent individuals expose themselves more regularly to disease-related pathogens through risky behaviors such as sharing pipes and needles, thereby increasing their risk for contracting an infectious disease. However, evidence is emerging indicating that not only lifestyle but also the immunomodulatory effects of addictive drugs, such as cocaine, may account for their high infection risk. As feelings of disgust are thought to be an important psychological mechanism in avoiding the exposure to pathogens, we sought to investigate behavioral, physiological, and immune responses to disgust-evoking cues in both cocaine-dependent and healthy men.
Methods: All participants (N = 61) were exposed to neutral and disgust-evoking photographs depicting food and nonfood images while response accuracy, latency, and skin conductivity were recorded. Saliva samples were collected before and after exposure to neutral and disgusting images, respectively. Attitudes toward disgust and hygiene behaviors were assessed using questionnaire measures.
Results: Response times to disgust-evoking photographs were prolonged in all participants, and specifically in cocaine-dependent individuals. While viewing the disgusting images, cocaine-dependent individuals exhibited aberrant skin conductivity and increased the secretion of the salivary cytokine interleukin-6 relative to control participants.
Conclusion: Our data provide evidence of a hypersensitivity to disgusting stimuli in cocaine-dependent individuals, possibly reflecting conditioned responses to noningestive sources of infection. Coupled with a lack of interoception of bodily signals, aberrant disgust responses might lead to increased infection susceptibility in affected individuals
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