20 research outputs found
The reference frame for encoding and retention of motion depends on stimulus set size
YesThe goal of this study was to investigate the reference
frames used in perceptual encoding and storage of visual
motion information. In our experiments, observers viewed
multiple moving objects and reported the direction of motion
of a randomly selected item. Using a vector-decomposition
technique, we computed performance during smooth pursuit
with respect to a spatiotopic (nonretinotopic) and to a
retinotopic component and compared them with performance
during fixation, which served as the baseline. For the stimulus
encoding stage, which precedes memory, we found that the
reference frame depends on the stimulus set size. For a single
moving target, the spatiotopic reference frame had the most
significant contribution with some additional contribution
from the retinotopic reference frame. When the number of
items increased (Set Sizes 3 to 7), the spatiotopic reference
frame was able to account for the performance. Finally, when
the number of items became larger than 7, the distinction
between reference frames vanished. We interpret this finding
as a switch to a more abstract nonmetric encoding of motion
direction. We found that the retinotopic reference frame was
not used in memory. Taken together with other studies, our
results suggest that, whereas a retinotopic reference frame
may be employed for controlling eye movements, perception
and memory use primarily nonretinotopic reference frames.
Furthermore, the use of nonretinotopic reference frames appears
to be capacity limited. In the case of complex stimuli, the
visual system may use perceptual grouping in order to simplify
the complexity of stimuli or resort to a nonmetric abstract
coding of motion information
Effect of renal denervation on blood pressure in the presence of antihypertensive drugs: 6-month efficacy and safety results from the SPYRAL HTN-ON MED proof-of-concept randomised trial.
: Previous catheter-based renal denervation studies have reported variable efficacy results. We aimed to evaluate safety and blood pressure response after renal denervation or sham control in patients with uncontrolled hypertension on antihypertensive medications with drug adherence testing. : In this international, randomised, single-blind, sham-control, proof-of-concept trial, patients with uncontrolled hypertension (aged 20-80 years) were enrolled at 25 centres in the USA, Germany, Japan, UK, Australia, Austria, and Greece. Eligible patients had an office systolic blood pressure of between 150 mm Hg and 180 mm Hg and a diastolic blood pressure of 90 mm Hg or higher; a 24 h ambulatory systolic blood pressure of between 140 mm Hg and 170 mm Hg at second screening; and were on one to three antihypertensive drugs with stable doses for at least 6 weeks. Patients underwent renal angiography and were randomly assigned to undergo renal denervation or sham control. Patients, caregivers, and those assessing blood pressure were masked to randomisation assignments. The primary efficacy endpoint was blood pressure change from baseline (measured at screening visit two), based on ambulatory blood pressure measurements assessed at 6 months, as compared between treatment groups. Drug surveillance was used to assess medication adherence. The primary analysis was done in the intention-to-treat population. Safety events were assessed through 6 months as per major adverse events. This trial is registered with ClinicalTrials.gov, number NCT02439775, and follow-up is ongoing. : Between July 22, 2015, and June 14, 2017, 467 patients were screened and enrolled. This analysis presents results for the first 80 patients randomly assigned to renal denervation (n=38) and sham control (n=42). Office and 24 h ambulatory blood pressure decreased significantly from baseline to 6 months in the renal denervation group (mean baseline-adjusted treatment differences in 24 h systolic blood pressure -7·0 mm Hg, 95% CI -12·0 to -2·1; p=0·0059, 24 h diastolic blood pressure -4·3 mm Hg, -7·8 to -0·8; p=0.0174, office systolic blood pressure -6·6 mm Hg, -12·4 to -0·9; p=0·0250, and office diastolic blood pressure -4·2 mm Hg, -7·7 to -0·7; p=0·0190). The change in blood pressure was significantly greater at 6 months in the renal denervation group than the sham-control group for office systolic blood pressure (difference -6·8 mm Hg, 95% CI -12·5 to -1·1; p=0·0205), 24 h systolic blood pressure (difference -7·4 mm Hg, -12·5 to -2·3; p=0·0051), office diastolic blood pressure (difference -3·5 mm Hg, -7·0 to -0·0; p=0·0478), and 24 h diastolic blood pressure (difference -4·1 mm Hg, -7·8 to -0·4; p=0·0292). Evaluation of hourly changes in 24 h systolic blood pressure and diastolic blood pressure showed blood pressure reduction throughout 24 h for the renal denervation group. 3 month blood pressure reductions were not significantly different between groups. Medication adherence was about 60% and varied for individual patients throughout the study. No major adverse events were recorded in either group. : Renal denervation in the main renal arteries and branches significantly reduced blood pressure compared with sham control with no major safety events. Incomplete medication adherence was common. : Medtronic.<br/
Association of respiratory symptoms and lung function with occupation in the multinational Burden of Obstructive Lung Disease (BOLD) study
Background
Chronic obstructive pulmonary disease has been associated with exposures in the workplace. We aimed to assess the association of respiratory symptoms and lung function with occupation in the Burden of Obstructive Lung Disease study.
Methods
We analysed cross-sectional data from 28 823 adults (≥40 years) in 34 countries. We considered 11 occupations and grouped them by likelihood of exposure to organic dusts, inorganic dusts and fumes. The association of chronic cough, chronic phlegm, wheeze, dyspnoea, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)/FVC with occupation was assessed, per study site, using multivariable regression. These estimates were then meta-analysed. Sensitivity analyses explored differences between sexes and gross national income.
Results
Overall, working in settings with potentially high exposure to dusts or fumes was associated with respiratory symptoms but not lung function differences. The most common occupation was farming. Compared to people not working in any of the 11 considered occupations, those who were farmers for ≥20 years were more likely to have chronic cough (OR 1.52, 95% CI 1.19–1.94), wheeze (OR 1.37, 95% CI 1.16–1.63) and dyspnoea (OR 1.83, 95% CI 1.53–2.20), but not lower FVC (β=0.02 L, 95% CI −0.02–0.06 L) or lower FEV1/FVC (β=0.04%, 95% CI −0.49–0.58%). Some findings differed by sex and gross national income.
Conclusion
At a population level, the occupational exposures considered in this study do not appear to be major determinants of differences in lung function, although they are associated with more respiratory symptoms. Because not all work settings were included in this study, respiratory surveillance should still be encouraged among high-risk dusty and fume job workers, especially in low- and middle-income countries.publishedVersio
Cohort Profile: Burden of Obstructive Lung Disease (BOLD) study
The Burden of Obstructive Lung Disease (BOLD) study was established to assess the prevalence of chronic airflow obstruction, a key characteristic of chronic obstructive pulmonary disease, and its risk factors in adults (≥40 years) from general populations across the world.
The baseline study was conducted between 2003 and 2016, in 41 sites across Africa, Asia, Europe, North America, the Caribbean and Oceania, and collected high-quality pre- and post-bronchodilator spirometry from 28 828 participants.
The follow-up study was conducted between 2019 and 2021, in 18 sites across Africa, Asia, Europe and the Caribbean. At baseline, there were in these sites 12 502 participants with high-quality spirometry. A total of 6452 were followed up, with 5936 completing the study core questionnaire. Of these, 4044 also provided high-quality pre- and post-bronchodilator spirometry.
On both occasions, the core questionnaire covered information on respiratory symptoms, doctor diagnoses, health care use, medication use and ealth status, as well as potential risk factors. Information on occupation, environmental exposures and diet was also collected
Acute and long-term outcome of Silverhawk assisted atherectomy for femoro-popliteal lesions according the TASC II classification: a single-center experience
Directional atherectomy (DA) has become popular in some centers to remove atherosclerotic plaques in femoro-popliteal lesions. Although immediate and also short - term outcome data are promising, solid long-term data are warranted to justify the widespread use in daily practice
Farm-based cropping pattern optimization and conjunctive use planning using piece-wise genetic algorithm (PWGA): a case study
Evaluation of the effective parameters on shear resistance of interface in a geocomposite-reinforced pavement
Rare structural variants disrupt multiple genes in neurodevelopmental pathways in schizophrenia
Schizophrenia is a devastating neurodevelopmental disorder whose genetic influences remain elusive. We hypothesize that individually rare structural variants contribute to the illness. Microdeletions and microduplications >100 kilobases were identified by microarray comparative genomic hybridization of genomic DNA from 150 individuals with schizophrenia and 268 ancestry-matched controls. All variants were validated by high-resolution platforms. Novel deletions and duplications of genes were present in 5% of controls versus 15% of cases and 20% of young-onset cases, both highly significant differences. The association was independently replicated in patients with childhood-onset schizophrenia as compared with their parents. Mutations in cases disrupted genes disproportionately from signaling networks controlling neurodevelopment, including neuregulin and glutamate pathways. These results suggest that multiple, individually rare mutations altering genes in neurodevelopmental pathways contribute to schizophrenia