Thirdhand smoke (THS) refers to components of secondhand smoke that stick to indoor surfaces and persist in the environment. Little is known about exposure levels and possible remediation measures to ...reduce potential exposure in contaminated areas. This study deals with the effect of aging on THS components and evaluates possible exposure levels and remediation measures. We investigated the concentration of nicotine, five nicotine related alkaloids, and three tobacco specific nitrosamines (TSNAs) in smoke exposed fabrics. Two different extraction methods were used. Cotton terry cloth and polyester fleece were exposed to smoke in controlled laboratory conditions and aged before extraction. Liquid chromatography-tandem mass spectrometry was used for chemical analysis. Fabrics aged for 19 months after smoke exposure retained significant amounts of THS chemicals. During aqueous extraction, cotton cloth released about 41 times as much nicotine and about 78 times the amount of tobacco specific nitrosamines (TSNAs) as polyester after one hour of aqueous extraction. Concentrations of nicotine and TSNAs in extracts of terry cloth exposed to smoke were used to estimate infant/toddler oral exposure and adult dermal exposure to THS. Nicotine exposure from THS residue can be 6.8 times higher in toddlers and 24 times higher in adults and TSNA exposure can be 16 times higher in toddlers and 56 times higher in adults than what would be inhaled by a passive smoker. In addition to providing exposure estimates, our data could be useful in developing remediation strategies and in framing public health policies for indoor environments with THS.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•PET motion correction from simultaneously acquired MR-derived motion model.•Fast MR acquisition freeing scan time per PET bed for further diagnostic sequences.•Clinically feasible setup: streamlined ...processing in Gadgetron evaluation on a cohort of 36 patients.•Publicly available: https://sites.google.com/site/kspaceastronauts.
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Purpose: To develop a motion correction for Positron-Emission-Tomography (PET) using simultaneously acquired magnetic-resonance (MR) images within 90 s.
Methods: A 90 s MR acquisition allows the generation of a cardiac and respiratory motion model of the body trunk. Thereafter, further diagnostic MR sequences can be recorded during the PET examination without any limitation. To provide full PET scan time coverage, a sensor fusion approach maps external motion signals (respiratory belt, ECG-derived respiration signal) to a complete surrogate signal on which the retrospective data binning is performed. A joint Compressed Sensing reconstruction and motion estimation of the subsampled data provides motion-resolved MR images (respiratory + cardiac). A 1-POINT DIXON method is applied to these MR images to derive a motion-resolved attenuation map. The motion model and the attenuation map are fed to the Customizable and Advanced Software for Tomographic Reconstruction (CASToR) PET reconstruction system in which the motion correction is incorporated. All reconstruction steps are performed online on the scanner via Gadgetron to provide a clinically feasible setup for improved general applicability. The method was evaluated on 36 patients with suspected liver or lung metastasis in terms of lesion quantification (SUVmax, SNR, contrast), delineation (FWHM, slope steepness) and diagnostic confidence level (3-point Likert-scale).
Results: A motion correction could be conducted for all patients, however, only in 30 patients moving lesions could be observed. For the examined 134 malignant lesions, an average improvement in lesion quantification of 22%, delineation of 64% and diagnostic confidence level of 23% was achieved.
Conclusion: The proposed method provides a clinically feasible setup for respiratory and cardiac motion correction of PET data by simultaneous short-term MRI. The acquisition sequence and all reconstruction steps are publicly available to foster multi-center studies and various motion correction scenarios.
A Cartesian subsampling scheme is proposed incorporating the idea of PF acquisition and variable-density Poisson Disc (vdPD) subsampling by redistributing the sampling space onto a smaller region ...aiming to increase k-space sampling density for a given acceleration factor. Especially the normally sparse sampled high-frequency components benefit from this sampling redistribution, leading to improved edge delineation. The prospective subsampled and compacted k-space can be reconstructed by a seamless combination of a CS-algorithm with a Hermitian symmetry constraint accounting for the missing part of the k-space. This subsampling and reconstruction scheme is called Compressed Sensing Partial Subsampling (ESPReSSo) and was tested on in-vivo abdominal MRI datasets. Different reconstruction methods and regularizations are investigated and analyzed via global (intensity-based) and local (region-of-interest and line evaluation) image metrics, to conclude a clinical feasible setup. Results substantiate that ESPReSSo can provide improved edge delineation and regional homogeneity for multidimensional and multi-coil MRI datasets and is therefore useful in applications depending on well-defined tissue boundaries, such as image registration and segmentation or detection of small lesions in clinical diagnostics.
Aims/hypothesis We and others recently characterised metabolically benign or healthy obesity (MHO). In the present study we investigated whether a lifestyle intervention is sufficient to place obese ...insulin-resistant (OIR) individuals in a position where the possible metabolic consequences are similar to those for MHO individuals. Methods A total of 262 non-diabetic individuals participated in a 9 month lifestyle intervention programme. Obese individuals (BMI ≥ 30.0 kg/m²) were stratified, based on their insulin sensitivity (IS) estimated from an OGTT, into MHO (IS in the upper quartile, n = 26) and OIR (IS in the lower three quartiles, n = 77). Total body and visceral fat were measured by magnetic resonance (MR) tomography and liver fat by ¹H-MR spectroscopy. Results During the intervention, visceral fat decreased significantly in both groups (both p ≤ 0.009), whereas total body and liver fat decreased only in the OIR group (p < 0.0001; MHO p = 0.12 for total body fat and p = 0.47 for liver fat). IS improved in the OIR group (p < 0.0001), but remained essentially unchanged in the MHO group (p = 0.30). However, despite the significant increase in the OIR group, IS at follow-up barely exceeded 50% of the IS of the MHO group (OIR 9.30 ± 0.53 arbitrary units AU; MHO 16.41 ± 1.05 AU; p < 0.0001). Conclusions/interpretation IS improves during the lifestyle intervention in OIR individuals. However, it does not reach a level where adequate protection from type 2 diabetes and cardiovascular disease is expected. Thus, stratification of obese individuals based on their metabolic phenotype is important to identify those who are likely to need early pharmacological treatment in addition to the lifestyle intervention.
On Technical Alterity Schick, Johannes F. M.
Foundations of science,
06/2022, Letnik:
27, Številka:
2
Journal Article
Recenzirano
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This commentary introduces the notion of “technical alterity” in order to address the following questions: is it possible that technical objects can become “others” in analogy to Levinas’ ethics and ...can this relation provide solutions for the subject in the Anthropocene? According to Levinas, the human subject’s only break from having to be itself is in the consumption and enjoyment of things. Objects constitute thus an “other” that can be consumed, i.e., appropriated and be made one’s own. But, in times of the Anthropocene, where the entanglement of human and non-human actors becomes increasingly obvious and intricate, and a question of survival for human beings in the face of the climate crisis, it is necessary to develop a relation with non-human actors that does not reduce them to mere means to an end. This ethical relation with technical objects relies upon an epistemic act, since technical objects precisely do not have a “face” in the Levinasian sense. Technical objects as “technical others” have therefore—in light of Simondon’s philosophy of technology—to be
invented
.
Lifestyle intervention with diet modification and increase in physical activity is effective for reducing hepatic steatosis in patients with non-alcoholic fatty liver disease (NAFLD). However, for a ...similar weight loss, there is a large variability in the change in liver fat. We hypothesised that cardiorespiratory fitness may predict the response to the intervention.
Longitudinal study with increase in physical activity and diet modification.
University teaching hospital.
50 adults with NAFLD and 120 controls at risk for metabolic diseases.
Total-, subcutaneous abdominal- and visceral adipose tissue by magnetic resonance tomography, liver fat by 1HMR spectroscopy and cardiorespiratory fitness (VO(2,max)) by a maximal cycle exercise test at baseline and after 9 months of follow-up.
In all subjects total-, subcutaneous abdominal- and visceral adipose tissue decreased and fitness increased (all p<0.0001) during the intervention. The most pronounced changes were found for liver fat (-31%, p<0.0001). Among the parameters predicting the change in liver fat, fitness at baseline emerged as the strongest factor, independently of total- and visceral adipose tissue as well as exercise intensity (p = 0.005). In the group of subjects with NAFLD at baseline, a resolution of NAFLD was found in 20 individuals. For 1 standard deviation increase in VO(2,max) at baseline the odds ratio for resolution of NAFLD was 2.79 (95% confidence interval, 1.43-6.33).
Cardiorespiratory fitness, independently of total adiposity, body fat distribution and exercise intensity, determines liver fat content in humans, suggesting that fitness and liver fat are causally related to each other. Moreover, measurement of fitness at baseline predicts the effectiveness of a lifestyle intervention in reducing hepatic steatosis in patients with NAFLD.
Magnetic resonance (MR) imaging offers a wide variety of imaging techniques. A large amount of data is created per examination which needs to be checked for sufficient quality in order to derive a ...meaningful diagnosis. This is a manual process and therefore time- and cost-intensive. Any imaging artifacts originating from scanner hardware, signal processing or induced by the patient may reduce the image quality and complicate the diagnosis or any image post-processing. Therefore, the assessment or the ensurance of sufficient image quality in an automated manner is of high interest. Usually no reference image is available or difficult to define. Therefore, classical reference-based approaches are not applicable. Model observers mimicking the human observers (HO) can assist in this task. Thus, we propose a new machine-learning-based reference-free MR image quality assessment framework which is trained on HO-derived labels to assess MR image quality immediately after each acquisition. We include the concept of active learning and present an efficient blinded reading platform to reduce the effort in the HO labeling procedure. Derived image features and the applied classifiers (support-vector-machine, deep neural network) are investigated for a cohort of 250 patients. The MR image quality assessment framework can achieve a high test accuracy of 93.7% for estimating quality classes on a 5-point Likert-scale. The proposed MR image quality assessment framework is able to provide an accurate and efficient quality estimation which can be used as a prospective quality assurance including automatic acquisition adaptation or guided MR scanner operation, and/or as a retrospective quality assessment including support of diagnostic decisions or quality control in cohort studies.
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•Automatic reference-free quality assessment of medical images•Prediction of human observer scores based on underlying diagnostic question•Reduced labeling effort by active learning•Investigation on suitable features and classifiers (SVM, DNN)•Accuracy of 93.7% for estimating quality classes on a 5-point Likert scale
Aims/hypothesis Impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) are risk factors for type 2 diabetes and cardiovascular disease; however, their impact on these endpoints differs. ...Because liver fat and visceral fat are important determinants of glucose and lipid metabolism, we investigated whether these fat compartments and their humoral products, the adipokine adiponectin and the hepatokine fetuin-A, differ in their impact on the glucose categories. Methods In 330 individuals at risk of type 2 diabetes, glucose tolerance status was determined by a 2 h 75 g OGTT. Total-body and visceral fat were precisely quantified by magnetic resonance (MR) tomography and liver fat by ¹H-MR spectroscopy. Results A total of 210 individuals had normal glucose tolerance (NGT), 41 isolated IFG, 43 isolated IGT and 36 IFG+IGT. Total-body fat was not different (p = 0.51), although a small but continuous increase in visceral fat was found among the categories after adjustment for age and sex (NGT: 3.07 ± 0.10 kg; IFG: 3.11 ± 0.21 kg; IGT: 3.61 ± 0.21 kg; IFG+IGT: 3.84 ± 0.23 kg SEs, p = 0.03). A larger difference was found for liver fat (NGT: 4.73 ± 0.42%; IFG: 5.86 ± 0.92%; IGT: 8.65 ± 0.92%; IFG + IGT: 11.11 ± 1.01%, p < 0.0001). The differences among the categories were small for adiponectin (p = 0.14), but larger for fetuin-A (p = 0.015). Among fat compartments, liver fat (p < 0.0001) and among circulating variables fetuin-A (p = 0.016) were the strongest determinants of the categories. Conclusions/interpretation Liver fat, more than visceral fat, strongly increases when glycaemia and glucose tolerance move from NGT to isolated IFG, isolated IGT and IFG+IGT. Because liver-derived circulating fetuin-A determines, although weakly, prediabetes categories, it is worth searching for hepatokines more strongly predicting prediabetes.
•THS exposure significantly increased pan-tumor incidence in CC mice.•THS exposure significantly reduced pan-tumor-free survival in CC mice.•Tumor susceptibility after THS exposure varied ...significantly across different CC strains.•Genetic background plays an important role in THS exposure-induced mouse tumorigenesis.
Increasing evidence has shown that thirdhand smoke (THS) exposure is likely to induce adverse health effects. An important knowledge gap remains in our understanding of THS exposure related to cancer risk in the human population. Population-based animal models are useful and powerful in investigating the interplay between host genetics and THS exposure on cancer risk. Here, we used the Collaborative Cross (CC) mouse population-based model system, which recapitulates the genetic and phenotypic diversity observed in the human population, to assess cancer risk after a short period of exposure, between 4 and 9 weeks of age. Eight CC strains (CC001, CC019, CC026, CC036, CC037, CC041, CC042 and CC051) were included in our study. We quantified pan-tumor incidence, tumor burden per mouse, organ tumor spectrum and tumor-free survival until 18 months of age. At the population level, we observed a significantly increased pan-tumor incidence and tumor burden per mouse in THS-treated mice as compared to the control (p = 3.04E-06). Lung and liver tissues exhibited the largest risk of undergoing tumorigenesis after THS exposure. Tumor-free survival was significantly reduced in THS-treated mice compared to control (p = 0.044). At the individual strain level, we observed a large variation in tumor incidence across the 8 CC strains. CC036 and CC041 exhibited a significant increase in pan-tumor incidence (p = 0.0084 and p = 0.000066, respectively) after THS exposure compared to control. We conclude that early-life THS exposure increases tumor development in CC mice and that host genetic background plays an important role in individual susceptibility to THS-induced tumorigenesis. Genetic background is an important factor that should be taken into account when determining human cancer risk of THS exposure.
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