Stepping impairments are associated with physical and cognitive decline in older adults and increased fall risk. Exercise interventions can reduce fall risk, but adherence is often low. A new ...exergame involving step training may provide an enjoyable exercise alternative for preventing falls in older people.
To assess the feasibility and safety of unsupervised, home-based step pad training and determine the effectiveness of this intervention on stepping performance and associated fall risk in older people.
Single-blinded two-arm randomized controlled trial comparing step pad training with control (no-intervention).
Thirty-seven older adults residing in independent-living units of a retirement village in Sydney, Australia.
Intervention group (IG) participants were provided with a computerized step pad system connected to their TVs and played a step game as often as they liked (with a recommended dose of 2-3 sessions per week for 15-20 minutes each) for eight weeks. In addition, IG participants were asked to complete a choice stepping reaction time (CSRT) task once each week.
CSRT, the Physiological Profile Assessment (PPA), neuropsychological and functional mobility measures were assessed at baseline and eight week follow-up.
Thirty-two participants completed the study (86.5%). IG participants played a median 2.75 sessions/week and no adverse events were reported. Compared to the control group, the IG significantly improved their CSRT (F31,1 = 18.203, p<.001), PPA composite scores (F31,1 = 12.706, p = 0.001), as well as the postural sway (F31,1 = 4.226, p = 0.049) and contrast sensitivity (F31,1 = 4.415, p = 0.044) PPA sub-component scores. In addition, the IG improved significantly in their dual-task ability as assessed by a timed up and go test/verbal fluency task (F31,1 = 4.226, p = 0.049).
Step pad training can be safely undertaken at home to improve physical and cognitive parameters of fall risk in older people without major cognitive and physical impairments.
Australian New Zealand Clinical Trials Registry ACTRN12611001081909.
Interactive cognitive-motor training (ICMT) requires individuals to perform both gross motor movements and complex information processing. This study investigated the effectiveness of ICMT on ...cognitive functions associated with falls in older adults.
A single-blinded randomized controlled trial was conducted in community-dwelling older adults (N = 90, mean age 81.5±7) without major cognitive impairment. Participants in the intervention group (IG) played four stepping games that required them to divide attention, inhibit irrelevant stimuli, switch between tasks, rotate objects and make rapid decisions. The recommended minimum dose was three 20-minute sessions per week over a period of 16 weeks unsupervised at home. Participants in the control group (CG) received an evidence-based brochure on fall prevention. Measures of processing speed, attention/executive function (EF), visuo-spatial ability, concerns about falling and depression were assessed before and after the intervention.
Eighty-one participants (90%) attended re-assessment. There were no improvements with respect to the Stroop Stepping Test (primary outcome) in the intervention group. Compared to the CG, the IG improved significantly in measures of processing speed, visuo-spatial ability and concern about falling. Significant interactions were observed for measures of EF and divided attention, indicating group differences varied for different levels of the covariate with larger improvements in IG participants with poorer baseline performance. The interaction for depression showed no change for the IG but an increase in the CG for those with low depressive symptoms at baseline. Additionally, low and high-adherer groups differed in their baseline performance and responded differently to the intervention. Compared to high adherers, low adherers improved more in processing speed and visual scanning while high-adherers improved more in tasks related to EF.
This study shows that unsupervised stepping ICMT led to improvements in specific cognitive functions associated with falls in older people. Low adherers improved in less complex functions while high-adherers improved in EF.
Australian New Zealand Clinical Trials Registry ACTRN12613000671763.
Summary Background Dabrafenib plus trametinib treatment provides significant benefits over BRAF-inhibitor monotherapy in patients with BRAFV600E -mutant or BRAFV600K -mutant advanced melanoma; ...however, in many patients the disease progresses, leading to death. With many treatment options available, understanding clinical factors that predict long-term response and survival for treatments is important for optimisation of patient management. We aimed to identify clinical factors associated with long-term response and survival using pooled data from randomised trials of dabrafenib plus trametinib in patients with metastatic BRAF -mutant melanoma. Methods We did a retrospective individual data analysis based on all published randomised trials that included treatment-naive patients with BRAFV600E -mutant or BRAFV600K -mutant metastatic melanoma who received the approved dose of dabrafenib 150 mg twice daily plus trametinib 2 mg once daily. Data were pooled from patients in the BRF113220 (part C; March 26, 2010, to Jan 15, 2015), COMBI-d (May 4, 2012, to Jan 12, 2015), and COMBI-v (June 4, 2012, to March 13, 2015) randomised trials. Patients with untreated brain metastases were not permitted to enrol in these trials. Baseline factors, identified a priori based on known melanoma clinical or prognostic characteristics, were analysed for association with progression-free survival and overall survival using univariate and multivariate analyses and assessed for hierarchical effect on outcomes using regression tree analyses. We also analysed factors identified after baseline, on treatment, and at progression, for associations with survival after progression. The trials included in this analysis are registered with ClinicalTrials.gov : BRF113220, number NCT01072175 ; COMBI-d, number NCT01584648 ; COMBI-v, number NCT01597908. Findings 617 patients were included in this analysis with a median follow-up of 20·0 months (range 0−48·0, IQR 10·1−24·8); 396 patients had progression events (ie, disease progression or death) and 290 patients had died. Median progression-free survival (11·1 months 95% CI 9·7−12·9), median overall survival (25·6 months 23·1−34·3), 1-year progression-free survival (48% 44–52) and overall survival (74% 71–78), and 2-year progression-free survival (30% 26–34) and overall survival (53% 49–57) were consistent with those in the individual trials. Patients with normal lactate dehydrogenase (LDH) concentration and fewer than three organ sites containing metastases (n=237) had the longest 1-year progression-free survival (68% 95% CI 62–74) and overall survival (90% 87–94) and 2-year progression-free survival (46% 40–54) and overall survival (75% 70–81), whereas patients with LDH concentration at least two times the upper limit of normal (n=70) had the shortest 1-year progression-free survival (8% 3–19) and overall survival (40% 29–55) and 2-year progression-free survival (2% 0–13) and overall survival (7% 3–19). Of patients with disease progression (n=379), survival after progression was longest in those with progression in baseline or new non-CNS lesions (n=205; median 10·0 months 95% CI 7·9−12·0) and shortest in those with new CNS lesions or concurrent progression in baseline and new lesions (n=171; median 4·0 months 3·5−4·9). Interpretation Several patient and clinical characteristics at and after baseline are associated with outcomes with dabrafenib plus trametinib, and durable benefit is possible with targeted treatment in defined patient subsets. Funding Novartis.
The COVID-19 pandemic has necessitated a multifaceted rapid response by the scientific community, bringing researchers, health officials, and industry together to address the ongoing public health ...emergency. To meet this challenge, participants need an informed approach for working safely with the etiological agent, the novel human coronavirus SARS-CoV-2. Work with infectious SARS-CoV-2 is currently restricted to high-containment laboratories, but material can be handled at a lower containment level after inactivation. Given the wide array of inactivation reagents that are being used in laboratories during this pandemic, it is vital that their effectiveness is thoroughly investigated. Here, we evaluated a total of 23 commercial reagents designed for clinical sample transportation, nucleic acid extraction, and virus inactivation for their ability to inactivate SARS-CoV-2, as well as seven other common chemicals, including detergents and fixatives. As part of this study, we have also tested five filtration matrices for their effectiveness at removing the cytotoxic elements of each reagent, permitting accurate determination of levels of infectious virus remaining following treatment. In addition to providing critical data informing inactivation methods and risk assessments for diagnostic and research laboratories working with SARS-CoV-2, these data provide a framework for other laboratories to validate their inactivation processes and to guide similar studies for other pathogens.
Infectious SARS-CoV-2 can be recovered from the oral cavities and saliva of COVID-19 patients with potential implications for disease transmission. Reducing viral load in patient saliva using ...antiviral mouthwashes may therefore have a role as a control measure in limiting virus spread, particularly in dental settings. Here, the efficacy of SARS-CoV-2 inactivation by seven commercially available mouthwashes with a range of active ingredients were evaluated
. We demonstrate ≥4.1 to ≥5.5 log
reduction in SARS-CoV-2 titre following a 1 min treatment with commercially available mouthwashes containing 0.01-0.02 % stabilised hypochlorous acid or 0.58 % povidone iodine, and non-specialist mouthwashes with both alcohol-based and alcohol-free formulations designed for home use. In contrast, products containing 1.5 % hydrogen peroxide or 0.2 % chlorhexidine gluconate were ineffective against SARS-CoV-2 in these tests. This study contributes to the growing body of evidence surrounding virucidal efficacy of mouthwashes/oral rinses against SARS-CoV-2, and has important applications in reducing risk associated with aerosol generating procedures in dentistry and potentially for infection control more widely.
Abstract
Reverse-transcription quantitative polymerase chain reaction assays are frequently used to evaluate gene expression in animal model studies. Data analyses depend on normalization using a ...suitable reference gene (RG) to minimize effects of variation due to sample collection, sample processing, or experimental set-up. Here, we investigated the suitability of nine potential RGs in laboratory animals commonly used to study viral hemorrhagic fever infection. Using tissues (liver, spleen, gonad ovary or testis, kidney, heart, lung, eye, brain, and blood) collected from naïve animals and those infected with Crimean–Congo hemorrhagic fever (mice), Nipah (hamsters), or Lassa (guinea pigs) viruses, optimal species-specific RGs were identified based on five web-based algorithms to assess RG stability. Notably, the
Ppia
RG demonstrated stability across all rodent tissues tested. Optimal RG pairs that include
Ppia
were determined for each rodent species (
Ppia
and
Gusb
for mice;
Ppia
and
Hrpt
for hamsters; and
Ppia
and
Gapdh
for guinea pigs). These RG pair assays were multiplexed with viral targets to improve assay turnaround time and economize sample usage. Finally, a pan-rodent
Ppia
assay capable of detecting
Ppia
across multiple rodent species was developed and successfully used in ecological investigations of field-caught rodents, further supporting its pan-species utility.
Enhancement of bedrock permeability by weathering Worthington, Stephen R.H.; Davies, Gareth J.; Alexander, E. Calvin
Earth-science reviews,
September 2016, 2016-09-00, 20160901, Letnik:
160
Journal Article
Recenzirano
The permeability of bedrock aquifers varies by more than four orders of magnitude between different lithologies, but the reasons for this large range remain unexplained. In this review, we examine ...the role that weathering plays in enhancing the permeability of the five major hydrolithologies, represented by limestone, basalt, granite, sandstone and shale. In limestone aquifers, rapid dissolution kinetics and congruent dissolution result in widespread permeability enhancement. Weathering is usually focused along fractures, and feedbacks between flow and dissolution result in self-organization into networks of channels that discharge at springs. Caves represent prominent examples of weathering. In silicate aquifers, slower dissolution kinetics and incongruent dissolution make it more difficult to predict permeability enhancement. However, positive correlations between permeability and both the solute concentrations and the dissolution rates of the five major lithologies suggest that weathering is a major factor that enhances permeability in silicate as well as in carbonate aquifers. This explains why the largest springs occur in the most permeable lithologies, why groundwater velocities >10m/d are common, and why microbial contamination is more common in bedrock aquifers than in unconsolidated sediments. Differences in weathering rates explain why limestone is much more permeable than shale, and why mafic igneous rocks such as basalt have higher permeabilities than felsic igneous rocks such as granite. Weathering appears to play an important role in enhancing permeability in most bedrock aquifers.
Invertebrates are dominant species in primary tropical rainforests, where their abundance and diversity contributes to the functioning and resilience of these globally important ecosystems. However, ...more than one-third of tropical forests have been logged, with dramatic impacts on rainforest biodiversity that may disrupt key ecosystem processes. We find that the contribution of invertebrates to three ecosystem processes operating at three trophic levels (litter decomposition, seed predation and removal, and invertebrate predation) is reduced by up to one-half following logging. These changes are associated with decreased abundance of key functional groups of termites, ants, beetles and earthworms, and an increase in the abundance of small mammals, amphibians and insectivorous birds in logged relative to primary forest. Our results suggest that ecosystem processes themselves have considerable resilience to logging, but the consistent decline of invertebrate functional importance is indicative of a human-induced shift in how these ecological processes operate in tropical rainforests.
The Transiting Exoplanet Survey Satellite (TESS) is performing a near all-sky survey for planets that transit bright stars. In addition, its excellent photometric precision enables asteroseismology ...of solar-type and red-giant stars, which exhibit convection-driven, solar-like oscillations. Simulations predict that TESS will detect solar-like oscillations in nearly 100 stars already known to host planets. In this paper, we present an asteroseismic analysis of the known red-giant host stars HD 212771 and HD 203949, both systems having a long-period planet detected through radial velocities. These are the first detections of oscillations in previously known exoplanet-host stars by TESS, further showcasing the mission's potential to conduct asteroseismology of red-giant stars. We estimate the fundamental properties of both stars through a grid-based modeling approach that uses global asteroseismic parameters as input. We discuss the evolutionary state of HD 203949 in depth and note the large discrepancy between its asteroseismic mass (M* = 1.23 0.15 M if on the red-giant branch or M* = 1.00 0.16 M if in the clump) and the mass quoted in the discovery paper (M* = 2.1 0.1 M ), implying a change >30% in the planet's mass. Assuming HD 203949 to be in the clump, we investigate the planet's past orbital evolution and discuss how it could have avoided engulfment at the tip of the red-giant branch. Finally, HD 212771 was observed by K2 during its Campaign 3, thus allowing for a preliminary comparison of the asteroseismic performances of TESS and K2. We estimate the ratio of the observed oscillation amplitudes for this star to be , consistent with the expected ratio of ∼0.85 due to the redder bandpass of TESS.
Abstract
To accurately characterize the planets a star may be hosting, stellar parameters must first be well determined.
τ
Ceti is a nearby solar analog and often a target for exoplanet searches. ...Uncertainties in the observed rotational velocities have made constraining
τ
Ceti’s inclination difficult. For planet candidates from radial velocity (RV) observations, this leads to substantial uncertainties in the planetary masses, as only the minimum mass (
m
sin
i
) can be constrained with RV. In this paper, we used new long-baseline optical interferometric data from the CHARA Array with the MIRC-X beam combiner and extreme precision spectroscopic data from the Lowell Discovery Telescope with EXPRES to improve constraints on the stellar parameters of
τ
Ceti. Additional archival data were obtained from a Tennessee State University Automatic Photometric Telescope and the Mount Wilson Observatory HK project. These new and archival data sets led to improved stellar parameter determinations, including a limb-darkened angular diameter of 2.019 ± 0.012 mas and rotation period of 46 ± 4 days. By combining parameters from our data sets, we obtained an estimate for the stellar inclination of 7° ± 7°. This nearly pole-on orientation has implications for the previously reported exoplanets. An analysis of the system dynamics suggests that the planetary architecture described by Feng et al. may not retain long-term stability for low orbital inclinations. Additionally, the inclination of
τ
Ceti reveals a misalignment between the inclinations of the stellar rotation axis and the previously measured debris disk rotation axis (
i
disk
= 35° ± 10°).
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