10 research outputs found
Effects of Lysophosphatidic Acid (LPA) and Antidiuretic Hormone (ADH) on Cl- Secretory Responses in Polycystic Kidney Disease (PKD)
poster abstractPolycystic kidney disease (PKD) is a genetic disease that causes the formation of fluid-filled cysts
in the kidney and other organs such as the liver and pancreas. Kidney function is seemingly
unaltered despite substantial cyst development over the first four to six decades of life, but then
the decline in renal function is precipitous often leading to complete renal failure in 5 years.
Antidiuretic hormone (ADH) causes an increase in Cl- secretion into the cyst lumen, and one of
the drugs in human clinical trials for treatment of PKD is an ADH receptor antagonist. The
hormone works by stimulating cAMP production, which leads to the Cl- secretion. Interestingly,
we have found that cyst fluid from human patients also causes a secretory Cl- flux that can lead to
the growth of the remaining intact cysts. The active component of the cyst fluid is LPA, a
phospholipid that acts as an extracellular signaling molecule. This secretion is important in late
stage disease when large cysts are likely to leak or burst contributing to the rapid decline in renal
function. Electrophysiological techniques were implemented to compare the ion fluxes stimulated
by ADH and LPA. In the mpkCCDc14 (mouse principal cells of the cortical collecting duct clone
4) cell line we found that the Cl- secretory pathways stimulated by the two factors are separate
and independent. Further indication of this separation is our finding that LPA stimulation does
not increase cAMP levels. Therefore we have identified an additional target for potential
pharmaceutical intervention in the treatment of PKD
Inhibition of cyst growth in PCK and Wpk rat models of polycystic kidney disease with low doses of peroxisome proliferator-activated receptor Îł agonists
Background and Objectives
The studies were designed to test the efficacy of two peroxisome proliferator-activated receptor Îł (PPARÎł) agonists in two rodent models of polycystic kidney disease (PKD).
Materials and Methods
The PCK rat is a slowly progressing cystic model while the Wpk-/- rat is a rapidly progressing model. PCK rats were fed with a pharmacological (0.4 mg/kg body weight [BW]) and a sub-pharmacological (0.04 mg/kg BW) dose of rosiglitazone (week 4â28). Wpk-/- rats were fed with pharmacological (2.0 mg/kg BW) and sub-pharmacologic (0.2 mg/kg BW) doses of pioglitazone from day 5 to 18. At termination, kidney weights of treated versus untreated cystic animals were used to determine efficacy. The current studies were also compared with previous studies containing higher doses of PPARÎł agonists. The concentrations used in the animals were calculated with reference to equivalent human doses for both drugs.
Results
The current studies demonstrate: 1) that low, pharmacologically relevant, doses of the PPARγ agonists effectively inhibit cyst growth; 2) there is a class action of the drugs with both commercially available PPARγ agonists, rosiglitazone, and pioglitazone, inhibiting cyst growth; 3) the drugs showed efficacy in two different preclinical cystic models. In the PCK rat, animals fed with a sub-pharmacological dose of rosiglitazone for 24 weeks had significantly lower kidney weights than untreated animals (3.68 ± 0.13 g vs. 4.17 ± 0. 11 g, respectively, P < 0.01) while treatment with a pharmacologic dose had no significant effect on kidney weight. The rapidly progressing Wpk-/- rats were fed with pharmacological and sub-pharmacologic doses of pioglitazone from day 5 to 18 and the kidneys were compared with non-treated, cystic animals. Kidney weights on the pharmacologic dose were not statistically lower than the untreated animals while rats fed a sub-pharmacologic dose showed a significant decrease compared with untreated animals (3.35 ± 0.15 g vs. 4.55 ± 0.46 g, respectively, P = 0.045).
Conclusion
Concentrations of PPARÎł agonists below the human equivalent diabetic doses are effective in slowing cyst growth in two rodent models of PKD
TeenCovidLife: a resource to understand the impact of the COVID-19 pandemic on adolescents in Scotland
TeenCovidLife is part of Generation Scotlandâs CovidLife projects, a set of longitudinal observational studies designed to assess the psychosocial and health impacts of the COVID-19 pandemic. TeenCovidLife focused on how adolescents in Scotland were coping during the pandemic. As of September 2021, Generation Scotland had conducted three TeenCovidLife surveys. Participants from previous surveys were invited to participate in the next, meaning the age ranges shifted over time.
TeenCovidLife Survey 1 consists of data from 5,543 young people age 12 to 17, collected from 22 May to 5 July 2020, during the first school closures period in Scotland. TeenCovidLife Survey 2 consists of data from 2,245 young people aged 12 to 18, collected from 18 August to 14 October 2020, when the initial lockdown measures were beginning to ease, and schools reopened in Scotland. TeenCovidLife Survey 3 consists of data from 597 young people age 12 to 19, collected from 12 May to 27 June 2021, a year after the first survey, after the schools returned following the second lockdown in 2021. A total of 316 participants took part in all three surveys.
TeenCovidLife collected data on general health and well-being, as well as topics specific to COVID-19, such as adherence to COVID-19 health guidance, feelings about school closures, and the impact of exam cancellations.
Limited work has examined the impact of the COVID-19 pandemic on young people. TeenCovidLife provides relevant and timely data to assess the impact of the pandemic on young people in Scotland. The dataset is available under authorised access from Generation Scotland; see the Generation Scotland website for more information
TeenCovidLife:a resource to understand the impact of the COVID-19 pandemic on adolescents in Scotland
Neurofeedback of Slow Cortical Potentials in Children with Attention-Deficit/Hyperactivity Disorder: A Multicenter Randomized Trial Controlling for Unspecific Effects
Background: Neurofeedback (NF) in children with attention-deficit/hyperactivity disorder (ADHD) has been investigated in a series of studies over the last years. Previous studies did not unanimously support NF as a treatment in ADHD. Most studies did not control for unspecific treatment effects and did not demonstrate that self-regulation took place. The present study examined the efficacy of NF in comparison to electromyographic (EMG) feedback to control for unspecific effects of the treatment, and assessed self-regulation of slow cortical potentials (SCPs).
Methods: A total of 150 children aged 7â9 years diagnosed with ADHD (82% male; 43% medicated) were randomized to 25 sessions of feedback of SCPs (NF) or feedback of coordination of the supraspinatus muscles (EMG). The primary endpoint was the change in parentsâ ratings of ADHD core symptoms 4 weeks after the end of treatment compared to pre-tests.
Results: Children in both groups showed reduced ADHD-core symptoms (NF 0.3, 95% CI -0.42 to -0.18; EMG 0.13, 95% CI -0.26 to -0.01). NF showed a significant superiority over EMG (treatment difference 0.17, 95% CI 0.02â0.3, p = 0.02). This yielded an effect size (ES) of d = 0.57 without and 0.40 with baseline observation carried forward (BOCF). The sensitivity analysis confirmed the primary result. Successful self-regulation of brain activity was observed only in NF. As a secondary result teachers reported no superior improvement from NF compared to EMG, but within-group analysis revealed effects of NF on the global ADHD score, inattention, and impulsivity. In contrast, EMG feedback did not result in changes despite more pronounced self-regulation learning.
Conclusions: Based on the primary parent-rated outcome NF proved to be superior to a semi-active EMG feedback treatment. The study supports the feasibility and efficacy of NF in a large sample of children with ADHD, based on both specific and unspecific effects
Lysophosphatidic Acid is a Modulator of Cyst Growth in Autosomal Dominant Polycystic Kidney Disease
Neurofeedback of Slow Cortical Potentials in Children with Attention-Deficit/Hyperactivity Disorder: A Multicenter Randomized Trial Controlling for Unspecific Effects
Background: Neurofeedback (NF) in children with attention-deficit/hyperactivity disorder (ADHD) has been investigated in a series of studies over the last years. Previous studies did not unanimously support NF as a treatment in ADHD. Most studies did not control for unspecific treatment effects and did not demonstrate that self-regulation took place. The present study examined the efficacy of NF in comparison to electromyographic (EMG) feedback to control for unspecific effects of the treatment, and assessed self-regulation of slow cortical potentials (SCPs). Methods: A total of 150 children aged 7-9 years diagnosed with ADHD (82% male; 43% medicated) were randomized to 25 sessions of feedback of SCPs (NF) or feedback of coordination of the supraspinatus muscles (EMG). The primary endpoint was the change in parents' ratings of ADHD core symptoms 4 weeks after the end of treatment compared to pre-tests. Results: Children in both groups showed reduced ADHD-core symptoms (NF 0.3, 95% CI -0.42 to -0.18; EMG 0.13, 95% CI -0.26 to -0.01). NF showed a significant superiority over EMG (treatment difference 0.17, 95% CI 0.02-0.3, p = 0.02). This yielded an effect size (ES) of d = 0.57 without and 0.40 with baseline observation carried forward (BOCF). The sensitivity analysis confirmed the primary result. Successful self-regulation of brain activity was observed only in NF. As a secondary result teachers reported no superior improvement from NF compared to EMG, but within-group analysis revealed effects of NF on the global ADHD score, inattention, and impulsivity. In contrast, EMG feedback did not result in changes despite more pronounced self-regulation learning. Conclusions: Based on the primary parent-rated outcome NF proved to be superior to a semi-active EMG feedback treatment. The study supports the feasibility and efficacy of NF in a large sample of children with ADHD, based on both specific and unspecific effects. Trial Register: Current controlled trials ISRCTN76187185, registered 5 February 2009
The risk of COVID-19 death is much greater and age dependent with type I IFN autoantibodies
International audienceSignificance There is growing evidence that preexisting autoantibodies neutralizing type I interferons (IFNs) are strong determinants of life-threatening COVID-19 pneumonia. It is important to estimate their quantitative impact on COVID-19 mortality upon SARS-CoV-2 infection, by age and sex, as both the prevalence of these autoantibodies and the risk of COVID-19 death increase with age and are higher in men. Using an unvaccinated sample of 1,261 deceased patients and 34,159 individuals from the general population, we found that autoantibodies against type I IFNs strongly increased the SARS-CoV-2 infection fatality rate at all ages, in both men and women. Autoantibodies against type I IFNs are strong and common predictors of life-threatening COVID-19. Testing for these autoantibodies should be considered in the general population
The risk of COVID-19 death is much greater and age dependent with type I IFN autoantibodies
International audienceSignificance There is growing evidence that preexisting autoantibodies neutralizing type I interferons (IFNs) are strong determinants of life-threatening COVID-19 pneumonia. It is important to estimate their quantitative impact on COVID-19 mortality upon SARS-CoV-2 infection, by age and sex, as both the prevalence of these autoantibodies and the risk of COVID-19 death increase with age and are higher in men. Using an unvaccinated sample of 1,261 deceased patients and 34,159 individuals from the general population, we found that autoantibodies against type I IFNs strongly increased the SARS-CoV-2 infection fatality rate at all ages, in both men and women. Autoantibodies against type I IFNs are strong and common predictors of life-threatening COVID-19. Testing for these autoantibodies should be considered in the general population