228 research outputs found
Case of carbon monoxide poisoning after smoking shisha
Carbon monoxide poisoning has been reported as a result of exposure to various sources of smoke, such as car exhaust fumes, home water heaters and tobacco smoke. We describe a case of symptomatic, moderately severe carbon monoxide (CO) poisoning in a young Mediterranean man after smoking a waterpipe, or shisha. This case highlights the importance of considering carbon monoxide exposure in patients presenting with non-specific neurological symptoms to the emergency department (ED)
A critique of the WHO TobReg's "Advisory Note" report entitled: "Waterpipe tobacco smoking: health effects, research needs and recommended actions by regulators"
BACKGROUND AND AIM: The World Health Organisation Study Group on Tobacco Product Regulation (TobReg) has issued in 2005 an "Advisory Note" entitled: "Waterpipe Tobacco Smoking: Health Effects, Research Needs and Recommended Actions by Regulators". "Waterpipe" smoking is now considered a global public health threat and the corresponding artefact is actually known in the world under three main terms: hookah, narghile and shisha. This important report, the first ever prepared by WHO on the subject, poses two major problems. On one hand, its bibliographical references dismiss world chief relevant studies. On the other, it contains a certain number of errors of many orders: biomedical, sociological, anthropological and historical. The purpose of the present study is to highlight, one by one, where these weaknesses and errors lie and show how this official report can be considerably improved. RESULTS: We realise that widely advertised early anthropological studies were not taken into consideration whereas they shed a substantial light on this peculiar form of smoking and help understanding its high complexity. As for concrete errors to be found in this report, they deal with the chemistry of smoke, health-related effects, smoking patterns, description and history of the artefact and its use, gender and underage use aspects, prevention and research needs in this field. CONCLUSION: The scientific credibility of an international expert report may be at stake if its recommendations do not rely on sound objective research findings and a comprehensive review of the existing literature. The critical comments in this study will certainly help improve the present WHO report
A Spatial Analysis of Rift Valley Fever Virus Seropositivity in Domestic Ruminants in Tanzania
Rift Valley fever (RVF) is an acute arthropod-borne viral zoonotic disease primarily occurring in Africa. Since RVF-like disease was reported in Tanzania in 1930, outbreaks of the disease have been reported mainly from the eastern ecosystem of the Great Rift Valley. This cross-sectional study was carried out to describe the variation in RVF virus (RVFV) seropositivity in domestic ruminants between selected villages in the eastern and western Rift Valley ecosystems in Tanzania, and identify potential risk factors. Three study villages were purposively selected from each of the two Rift Valley ecosystems. Serum samples from randomly selected domestic ruminants (n = 1,435) were tested for the presence of specific immunoglobulin G (IgG) and M (IgM), using RVF enzyme-linked immunosorbent assay methods. Mixed effects logistic regression modelling was used to investigate the association between potential risk factors and RVFV seropositivity. The overall RVFV seroprevalence (n = 1,435) in domestic ruminants was 25.8% and species specific seroprevalence was 29.7%, 27.7% and 22.0% in sheep (n = 148), cattle (n = 756) and goats (n = 531), respectively. The odds of seropositivity were significantly higher in animals sampled from the villages in the eastern than those in the western Rift Valley ecosystem (OR = 1.88, CI: 1.41, 2.51; p<0.001), in animals sampled from villages with soils of good than those with soils of poor water holding capacity (OR = 1.97; 95% CI: 1.58, 3.02; p< 0.001), and in animals which had been introduced than in animals born within the herd (OR = 5.08, CI: 2.74, 9.44; p< 0.001). Compared with animals aged 1-2 years, those aged 3 and 4-5 years had 3.40 (CI: 2.49, 4.64; p< 0.001) and 3.31 (CI: 2.27, 4.82, p< 0.001) times the odds of seropositivity. The findings confirm exposure to RVFV in all the study villages, but with a higher prevalence in the study villages from the eastern Rift Valley ecosystem
Cerebral Perfusion and Aortic Stiffness Are Independent Predictors of White Matter Brain Atrophy in Type 1 Diabetic Patients Assessed With Magnetic Resonance Imaging
OBJECTIVE-To identify vascular mechanisms of brain atrophy in type 1 diabetes mellitus (DM) patients by investigating the relationship between brain volumes and cerebral perfusion and aortic stiffness using magnetic resonance imaging (MRI). RESEARCH DESIGN AND METHODS-Approval from the local institutional review board was obtained, and patients gave informed consent. Fifty-one type 1 DM patients (30 men; mean age 44 +/- 11 years; mean DM duration 23 +/- 12 years) and 34 age- and sex-matched healthy control subjects were prospectively enrolled. Exclusion criteria comprised hypertension, stroke, aortic disease, and standard MRI contraindications. White matter (WM) and gray matter (GM) brain volumes, total cerebral blood flow (tCBF), total brain perfusion, and aortic pulse wave velocity (PWV) were assessed using MRI. Multivariable linear regression analysis was used for statistics, with covariates age, sex, mean arterial pressure, BMI, smoking, heart rate, DM duration, and HbA(1c). RESULTS-Both WM and GM brain volumes were decreased in type 1 DM patients compared with control subjects (WM P = 0.04; respective GM P = 0.03). Total brain perfusion was increased in type 1 DM compared with control subjects (beta = -0.219, P < 0.05). Total CBF and aortic PWV predicted WM brain volume (beta = 0.352, P = 0.024 for tCBF; respective beta = 0.458, P = 0.016 for aortic PWV) in type 1 DM. Age was the independent predictor of GM brain volume (beta = -0.695, P < 0.001). CONCLUSIONS-Type 1 DM patients without hypertension showed WM and GM volume loss compared with control subjects concomitant with a relative increased brain perfusion. Total CBF and stiffness of the aorta independently predicted WM brain atrophy in type 1 DM. Only age predicted GM brain atrophy.Cardiovascular Aspects of Radiolog
Structure and Dynamics of Cholesterol-Containing Polyunsaturated Lipid Membranes Studied by Neutron Diffraction and NMR
A direct and quantitative analysis of the internal structure and dynamics of a polyunsaturated lipid bilayer composed of 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (18:0-22:6n3-PC) containing 29Ā mol% cholesterol was carried out by neutron diffraction, 2H-NMR and 13C-MAS NMR. Scattering length distribution functions of cholesterol segments as well as of the sn-1 and sn-2 hydrocarbon chains of 18:0-22:6n3-PC were obtained by conducting experiments with specifically deuterated cholesterol and lipids. Cholesterol orients parallel to the phospholipids, with the A-ring near the lipid glycerol and the terminal methyl groups 3 Ć
away from the bilayer center. Previously, we reported that the density of polyunsaturated docosahexaenoic acid (DHA, 22:6n3) chains was higher near the lipidāwater interface. Addition of cholesterol partially redistributes DHA density from near the lipidāwater interface to the center of the hydrocarbon region. Cholesterol raises chain-order parameters of both stearic acid and DHA chains. The fractional order increase for stearic acid methylene carbons C8āC18 is larger, reflecting the redistribution of DHA chain density toward the bilayer center. The correlation times of DHA chain isomerization are short and mostly unperturbed by the presence of cholesterol. The uneven distribution of saturated and polyunsaturated chain densities and the cholesterol-induced balancing of chain distributions may have important implications for the function and integrity of membrane receptors, such as rhodopsin
Single nucleotide polymorphism discovery in rainbow trout by deep sequencing of a reduced representation library
<p>Abstract</p> <p>Background</p> <p>To enhance capabilities for genomic analyses in rainbow trout, such as genomic selection, a large suite of polymorphic markers that are amenable to high-throughput genotyping protocols must be identified. Expressed Sequence Tags (ESTs) have been used for single nucleotide polymorphism (SNP) discovery in salmonids. In those strategies, the salmonid semi-tetraploid genomes often led to assemblies of paralogous sequences and therefore resulted in a high rate of false positive SNP identification. Sequencing genomic DNA using primers identified from ESTs proved to be an effective but time consuming methodology of SNP identification in rainbow trout, therefore not suitable for high throughput SNP discovery. In this study, we employed a high-throughput strategy that used pyrosequencing technology to generate data from a reduced representation library constructed with genomic DNA pooled from 96 unrelated rainbow trout that represent the National Center for Cool and Cold Water Aquaculture (NCCCWA) broodstock population.</p> <p>Results</p> <p>The reduced representation library consisted of 440 bp fragments resulting from complete digestion with the restriction enzyme <it>Hae</it>III; sequencing produced 2,000,000 reads providing an average 6 fold coverage of the estimated 150,000 unique genomic restriction fragments (300,000 fragment ends). Three independent data analyses identified 22,022 to 47,128 putative SNPs on 13,140 to 24,627 independent contigs. A set of 384 putative SNPs, randomly selected from the sets produced by the three analyses were genotyped on individual fish to determine the validation rate of putative SNPs among analyses, distinguish apparent SNPs that actually represent paralogous loci in the tetraploid genome, examine Mendelian segregation, and place the validated SNPs on the rainbow trout linkage map. Approximately 48% (183) of the putative SNPs were validated; 167 markers were successfully incorporated into the rainbow trout linkage map. In addition, 2% of the sequences from the validated markers were associated with rainbow trout transcripts.</p> <p>Conclusion</p> <p>The use of reduced representation libraries and pyrosequencing technology proved to be an effective strategy for the discovery of a high number of putative SNPs in rainbow trout; however, modifications to the technique to decrease the false discovery rate resulting from the evolutionary recent genome duplication would be desirable.</p
Radioactive Holmium Acetylacetonate Microspheres for Interstitial Microbrachytherapy: An In Vitro and In Vivo Stability Study
Purpose The clinical application of holmium acetylacetonate microspheres (HoAcAcMS) for the intratumoral radionuclide treatment of solid malignancies requires a thorough understanding of their stability. Therefore, an in vitro and an in vivo stability study with HoAcAcMS was conducted. Methods HoAcAcMS, before and after neutron irradiation, were incubated in a phosphate buffer at 37Ā°C for 6 months. The in vitro release of holmium in this buffer after 6 months was 0.5%. Elemental analysis, scanning electron microscopy, infrared spectroscopy and time of flight secondary ion mass spectrometry were performed on the HoAcAcMS. Results After 4 days in buffer the acetylacetonate ligands were replaced by phosphate, without altering the particle size and surface morphology. HoAcAcMS before and after neutron irradiation were administered intratumorally in VX2 tumor-bearing rabbits. No holmium was detected in the faeces, urine, femur and blood. Histological examination of the tumor revealed clusters of intact microspheres amidst necrotic tissue after 30 days. Conclusion HoAcAcMS are stable both in vitro and in vivo and are suitable for intratumoral radionuclide treatment.Radiation, Radionuclides and ReactorsApplied Science
It is time to talk about people: a human-centered healthcare system
Examining vulnerabilities within our current healthcare system we propose borrowing two tools from the fields of engineering and design: a) Reason's system approach [1] and b) User-centered design [2,3]. Both approaches are human-centered in that they consider common patterns of human behavior when analyzing systems to identify problems and generate solutions. This paper examines these two human-centered approaches in the context of healthcare. We argue that maintaining a human-centered orientation in clinical care, research, training, and governance is critical to the evolution of an effective and sustainable healthcare system
A novel method to compare protein structures using local descriptors
<p>Abstract</p> <p>Background</p> <p>Protein structure comparison is one of the most widely performed tasks in bioinformatics. However, currently used methods have problems with the so-called "difficult similarities", including considerable shifts and distortions of structure, sequential swaps and circular permutations. There is a demand for efficient and automated systems capable of overcoming these difficulties, which may lead to the discovery of previously unknown structural relationships.</p> <p>Results</p> <p>We present a novel method for protein structure comparison based on the formalism of local descriptors of protein structure - DEscriptor Defined Alignment (DEDAL). Local similarities identified by pairs of similar descriptors are extended into global structural alignments. We demonstrate the method's capability by aligning structures in difficult benchmark sets: curated alignments in the SISYPHUS database, as well as SISY and RIPC sets, including non-sequential and non-rigid-body alignments. On the most difficult RIPC set of sequence alignment pairs the method achieves an accuracy of 77% (the second best method tested achieves 60% accuracy).</p> <p>Conclusions</p> <p>DEDAL is fast enough to be used in whole proteome applications, and by lowering the threshold of detectable structure similarity it may shed additional light on molecular evolution processes. It is well suited to improving automatic classification of structure domains, helping analyze protein fold space, or to improving protein classification schemes. DEDAL is available online at <url>http://bioexploratorium.pl/EP/DEDAL</url>.</p
Docosahexaenoic Acid-Derived Neuroprotectin D1 Induces Neuronal Survival via Secretase- and PPARĪ³-Mediated Mechanisms in Alzheimer's Disease Models
Neuroprotectin D1 (NPD1) is a stereoselective mediator derived from the omega-3 essential fatty acid docosahexaenoic acid (DHA) with potent inflammatory resolving and neuroprotective bioactivity. NPD1 reduces AĪ²42 peptide release from aging human brain cells and is severely depleted in Alzheimer's disease (AD) brain. Here we further characterize the mechanism of NPD1's neurogenic actions using 3xTg-AD mouse models and human neuronal-glial (HNG) cells in primary culture, either challenged with AĪ²42 oligomeric peptide, or transfected with beta amyloid precursor protein (Ī²APP)sw (Swedish double mutation APP695sw, K595N-M596L). We also show that NPD1 downregulates AĪ²42-triggered expression of the pro-inflammatory enzyme cyclooxygenase-2 (COX-2) and of B-94 (a TNF-Ī±-inducible pro-inflammatory element) and apoptosis in HNG cells. Moreover, NPD1 suppresses AĪ²42 peptide shedding by down-regulating Ī²-secretase-1 (BACE1) while activating the Ī±-secretase ADAM10 and up-regulating sAPPĪ±, thus shifting the cleavage of Ī²APP holoenzyme from an amyloidogenic into the non-amyloidogenic pathway. Use of the thiazolidinedione peroxisome proliferator-activated receptor gamma (PPARĪ³) agonist rosiglitazone, the irreversible PPARĪ³ antagonist GW9662, and overexpressing PPARĪ³ suggests that the NPD1-mediated down-regulation of BACE1 and AĪ²42 peptide release is PPARĪ³-dependent. In conclusion, NPD1 bioactivity potently down regulates inflammatory signaling, amyloidogenic APP cleavage and apoptosis, underscoring the potential of this lipid mediator to rescue human brain cells in early stages of neurodegenerations
- ā¦