Influence of Aerobic Exercise on Ghrelin-o-Acyltransferase in Normal Weight and Obese Adults: A Pilot Study

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Differential diagnosis of illness in travelers arriving from sierra Leone, Liberia, or guinea: A cross-sectional study from the Geosentinel surveillance network

Background: The largest-ever outbreak of Ebola virus disease (EVD), ongoing in West Africa since late 2013, has led to export of cases to Europe and North America. Clinicians encountering ill travelers arriving from countries with widespread Ebola virus transmission must be aware of alternate diagnoses associated with fever and other nonspecific symptoms. Objective: To define the spectrum of illness observed in persons returning from areas of West Africa where EVD transmission has been widespread. Design: Descriptive, using GeoSentinel records. Setting: 57 travel or tropical medicine clinics in 25 countries. Patients: 805 ill returned travelers and new mmigrants from Sierra Leone, Liberia, or Guinea seen between September 2009 and August 2014. Measurements: Frequencies of demographic and travelrelated characteristics and illnesses reported. Results: The most common specific diagnosis among 770 nonimmigrant travelers was malaria (n = 310 [40.3%]), with Plasmodium falciparum or severe malaria in 267 (86%) and non–P. falciparum malaria in 43 (14%). Acute diarrhea was the second most common diagnosis among nonimmigrant travelers (n= 95 [12.3%]). Such common diagnoses as upper respiratory tract infection, urinary tract infection, and influenza-like illness occurred in only 26, 9, and 7 returning travelers, respectively. Few instances of typhoid fever (n = 8), acute HIV infection (n = 5), and dengue (n = 2) were encountered. Limitation: Surveillance data collected by specialist clinics may not be representative of all ill returned travelers. Conclusion: Although EVD may currently drive clinical evaluation of ill travelers arriving from Sierra Leone, Liberia, and Guinea, clinicians must be aware of other more common, potentially fatal diseases. Malaria remains a common diagnosis among travelers seen at GeoSentinel sites. Prompt exclusion of malaria and other life-threatening conditions is critical to limiting morbidity and mortality

Novel Protocol for the Chemical Synthesis of Crustacean Hyperglycemic Hormone Analogues — An Efficient Experimental Tool for Studying Their Functions

The crustacean Hyperglycemic Hormone (cHH) is present in many decapods in different isoforms, whose specific biological functions are still poorly understood. Here we report on the first chemical synthesis of three distinct isoforms of the cHH of Astacus leptodactylus carried out by solid phase peptide synthesis coupled to native chemical ligation. The synthetic 72 amino acid long peptide amides, containing L- or D-Phe3 and (Glp1, D-Phe3) were tested for their biological activity by means of homologous in vivo bioassays. The hyperglycemic activity of the D-isoforms was significantly higher than that of the L-isoform, while the presence of the N-terminal Glp residue had no influence on the peptide activity. The results show that the presence of D-Phe3 modifies the cHH functionality, contributing to the diversification of the hormone pool

Systematic review of worldwide variations of the prevalence of wheezing symptoms in children

Background: Considerable variation in the prevalence of childhood asthma and its symptoms (wheezing) has been observed in previous studies and there is evidence that the prevalence has been increasing over time. Methods: We have systematically reviewed the reported prevalence and time trends of wheezing symptoms among children, worldwide and within the same country over time. All studies comprising more than 1000 persons and meeting certain other quality criteria published over a 16-year period, between January 1990 and December 2005, are reported and a comparison of ISAAC (International Study of Asthma and Allergies in Childhood) and non-ISAAC studies is made, in part as a way of expanding the power to examine time trends (the older studies tend to be non-ISAAC), but also to examine possible methodological differences between ISAAC and non-ISAAC questions. Results: A wide range of current prevalence of wheeze was observed between and within countries over time. The UK had the highest recorded prevalence of 32.2% in children aged 13–14 in 1994–5 and Ethiopia had the lowest prevalence, 1.7% in children aged 10–19 in 1996. All studies in Australia and the UK were compared using multiple logistic regression. ISAAC phase I and III studies reported significantly higher prevalence of current wheeze (OR = 1.638) compared with non-ISAAC studies, after adjusting for various other factors (country, survey year, age of child, parental vs child response to the survey). Australia showed a significantly higher prevalence of current wheezing (OR = 1.343) compared with the UK, there was a significant increase in the prevalence odds ratio per survey year (2.5% per year), a significant decrease per age of child (0.7% per year), and a significantly higher response in current wheezing if the response was self-completed by the child (OR = 1.290). These factors, when explored separately for ISAAC and non-ISAAC studies, showed very different results. In ISAAC studies, or non-ISAAC studies using ISAAC questions, there was a significant decrease in current wheezing prevalence over time (2.5% per year). In non-ISAAC studies, which tend to cover an earlier period, there was a significant increase (2.6% per year) in current wheezing prevalence over time. This is very likely to be a result of prevalence of wheezing increasing from the 1970s up to the early 1990s, but decreasing since then. Conclusion: The UK has the highest recorded prevalence of wheezing and Ethiopia the lowest. Prevalence of wheezing in Australia and the UK has increased from the 1970s up to the early 1990s, but decreased since then and ISAAC studies report significantly higher prevalences than non-ISAAC studies

Using combined diagnostic test results to hindcast trends of infection from cross-sectional data

Infectious disease surveillance is key to limiting the consequences from infectious pathogens and maintaining animal and public health. Following the detection of a disease outbreak, a response in proportion to the severity of the outbreak is required. It is thus critical to obtain accurate information concerning the origin of the outbreak and its forward trajectory. However, there is often a lack of situational awareness that may lead to over- or under-reaction. There is a widening range of tests available for detecting pathogens, with typically different temporal characteristics, e.g. in terms of when peak test response occurs relative to time of exposure. We have developed a statistical framework that combines response level data from multiple diagnostic tests and is able to ‘hindcast’ (infer the historical trend of) an infectious disease epidemic. Assuming diagnostic test data from a cross-sectional sample of individuals infected with a pathogen during an outbreak, we use a Bayesian Markov Chain Monte Carlo (MCMC) approach to estimate time of exposure, and the overall epidemic trend in the population prior to the time of sampling. We evaluate the performance of this statistical framework on simulated data from epidemic trend curves and show that we can recover the parameter values of those trends. We also apply the framework to epidemic trend curves taken from two historical outbreaks: a bluetongue outbreak in cattle, and a whooping cough outbreak in humans. Together, these results show that hindcasting can estimate the time since infection for individuals and provide accurate estimates of epidemic trends, and can be used to distinguish whether an outbreak is increasing or past its peak. We conclude that if temporal characteristics of diagnostics are known, it is possible to recover epidemic trends of both human and animal pathogens from cross-sectional data collected at a single point in time

Acute Muscular Sarcocystosis: An International Investigation Among Ill Travelers Returning From Tioman Island, Malaysia, 2011-2012

A large outbreak of acute muscular sarcocystosis (AMS) among international tourists who visited Tioman Island, Malaysia, is described. Clinicians evaluating travelers returning ill from Malaysia with myalgia, with or without fever, should consider AMS in their differential diagnosi

The impact of analog front-end filters on ultrasound harmonic imaging

\u3cp\u3eUltrasound (US) harmonic imaging has shown advantages in better spatial resolution and contrast compared to classic fundamental imaging, but it suffers from more attenuation due to the increased frequency. To achieve more penetration, high dynamic range (DR) front-end electronics is required to receive the weak harmonic components. Typical US front-ends use a variable gain amplifier (VGA) to compensate part of the required DR, in order to avoid using a highly sensitive analog-to-digital converter (ADC). However, in harmonic imaging, the received signal amplitude is dominated by the fundamental component, thus the VGA is less efficient for these small harmonics. An analog front-end filter can be used before the VGA to mitigate this issue but this has an impact on spatial resolution by changing the dominant frequency component and spatial pulse length of the received signal. In this work, a combined acoustic-and-electronic model is made to understand the impact of the use of an analog front-end filter in US harmonic imaging applications in terms of imaging resolution, contrast, and hardware requirements.\u3c/p\u3

Adaptive motion-artifact reduction in capacitive ECG measurements by using the power-line interference

Capacitive electrodes can be employed for noninvasive electrocardiography (ECG) measurements; they are especially suitable for long-term ambulatory monitoring. However, capacitive electrodes are very sensitive to motion artifacts (MAs) due to variable coupling distance. Adaptive filtering has been widely used for optimal MA reduction in biopotential measurements. Unfortunately, the existing adaptive-filtering methods require a reference signal recorded by additional sensors, limiting their applicability in ambulatory settings. In the present study, a novel adaptive MA removal method is proposed where the reference signal is extracted from the power-line interference (PLI). PLI usually appears in ECG measurements due to unbalanced electrode impedance. Movement of the electrodes causes not only MAs but also variations in the PLI. Demodulation of the PLI may, therefore, represent a reference signal reflecting the sensor movement for adaptive MA removal by signal decorrelation. Preliminary validation on both simulation and real data showed effective MA removal by the proposed adaptive filter, possibly leading to improved analysis of capacitive ECG signals in ambulatory settings

Arginine methylation of a mitochondrial guide RNA binding protein from Trypanosoma brucei

RBP16 is a mitochondrial Y-box protein from the parasitic protozoan Trypanosoma brucei that binds guide RNAs and ribosomal RNAs. It is comprised of an N-terminal cold-shock domain and a C-terminal domain rich in glycine and arginine residues, resembling the RGG RNA-binding motif. Arginine residues found within RGG domains are frequently asymmetrically dimethylated by a class of enzymes termed protein arginine methyltransferases (PRMTs). As Arg-93 of RBP16 exists in the context of a preferred sequence for asymmetric arginine dimethylation (G/FGGRGGG/F), we investigated whether modified arginines are present in native RBP16 by MALDI-TOF and post-source decay analyses. These analyses confirmed that Arg-93 is dimethylated. In addition, Arg-78 exists as an unmodified or as a monomethylated derivative, and Arg-85 is present in forms corresponding to the unmodified, di-, and tri-methylated state. While Arg-93 is apparently constitutively dimethylated, the methylation of Arg-78 and Arg-85 is mutually exclusive. Furthermore, whole cell extracts from procyclic form T. brucei are able to methylate bacterially expressed RBP16 (rRBP16), as well as endogenous proteins, in the presence of S-adenosyl- l-[ methyl- 3H]methionine. While assays of mitochondrial extracts suggest a small amount of PRMT may also be present in this subcellular compartment, the majority of trypanosome PRMT activity is extramitochondrial. We show that rRBP16 is methylated in trypanosome extracts through the action of a type I methyltransferase as well as serving as a substrate for heterologous mammalian type I PRMTs. In addition, we demonstrate the presence of type II PRMT activity in trypanosome cell extracts. These results suggest that protein arginine methylation is a common posttranslational modification in trypanosomes, and that it may regulate the function of RBP16

Adaptive motion-artifact reduction in capacitive ECG measurements by using the power-line interference

Capacitive electrodes can be employed for noninvasive electrocardiography (ECG) measurements; they are especially suitable for long-term ambulatory monitoring. However, capacitive electrodes are very sensitive to motion artifacts (MAs) due to variable coupling distance. Adaptive filtering has been widely used for optimal MA reduction in biopotential measurements. Unfortunately, the existing adaptive-filtering methods require a reference signal recorded by additional sensors, limiting their applicability in ambulatory settings. In the present study, a novel adaptive MA removal method is proposed where the reference signal is extracted from the power-line interference (PLI). PLI usually appears in ECG measurements due to unbalanced electrode impedance. Movement of the electrodes causes not only MAs but also variations in the PLI. Demodulation of the PLI may, therefore, represent a reference signal reflecting the sensor movement for adaptive MA removal by signal decorrelation. Preliminary validation on both simulation and real data showed effective MA removal by the proposed adaptive filter, possibly leading to improved analysis of capacitive ECG signals in ambulatory settings