86 research outputs found
Identification of a Locus on the X Chromosome Linked to Familial Membranous Nephropathy
INTRODUCTION:
Membranous nephropathy (MN) is the most common cause of nephrotic syndrome (NS) in adults and is a leading cause of end-stage renal disease due to glomerulonephritis. Primary MN has a strong male predominance, accounting for approximately 65% of cases; yet, currently associated genetic loci are all located on autosomes. Previous reports of familial MN have suggested the existence of a potential X-linked susceptibility locus. Identification of such risk locus may provide clues to the etiology of MN.
METHODS:
We identified 3 families with 8 members affected by primary MN. Genotyping was performed using single-nucleotide polymorphism microarrays, and serum was sent for anti-phospholipase A2 receptor (PLA2R) antibody testing. All affected members were male and connected through the maternal line, consistent with X-linked inheritance. Genome-wide multipoint parametric linkage analysis using a model of X-linked recessive inheritance was conducted, and genetic risk scores (GRSs) based on known MN-associated variants were determined.
RESULTS: Anti-PLA2R testing was negative in all affected family members. Linkage analysis revealed a significant logarithm of the odds score (3.260) on the short arm of the X chromosome at a locus of approximately 11 megabases (Mb). Haplotype reconstruction further uncovered a shared haplotype spanning 2 Mb present in all affected individuals from the 3 families. GRSs in familial MN were significantly lower than in anti-PLA2R–associated MN and were not different from controls.
CONCLUSIONS: Our study identifies linkage of familial membranous nephropathy to chromosome Xp11.3-11.22. Family members affected with MN have a significantly lower GRS than individuals with anti-PLA2R–associated MN, suggesting that X-linked familial MN represents a separate etiologic entity
Treatment of developmental dyslexia: A review
Remarkably few research articles on the treatment of developmental dyslexia were published during the last 25 years. Some treatment research arose from the temporal processing theory, some from the phonological deficit hypothesis and some more from the balance model of learning to read and dyslexia. Within the framework of that model, this article reviews the aetiology of dyslexia sub-types, the neuropsychological rationale for treatment, the treatment techniques and the outcomes of treatment research. The possible mechanisms underlying the effects of treatment are discussed. © 2005 Informa UK Ltd All rights reserved
An interplanetary shock traced by planetary auroral storms from the Sun to Saturn
A relationship between solar activity and aurorae on Earth was postulated(1,2) long before space probes directly detected plasma propagating outwards from the Sun(3). Violent solar eruption events trigger interplanetary shocks(4) that compress Earth's magnetosphere, leading to increased energetic particle precipitation into the ionosphere and subsequent auroral storms(5,6). Monitoring shocks is now part of the 'Space Weather' forecast programme aimed at predicting solar-activity-related environmental hazards. The outer planets also experience aurorae, and here we report the discovery of a strong transient polar emission on Saturn, tentatively attributed to the passage of an interplanetary shock - and ultimately to a series of solar coronal mass ejection (CME) events. We could trace the shock-triggered events from Earth, where auroral storms were recorded, to Jupiter, where the auroral activity was strongly enhanced, and to Saturn, where it activated the unusual polar source. This establishes that shocks retain their properties and their ability to trigger planetary auroral activity thoughout the Solar System. Our results also reveal differences in the planetary auroral responses on the passing shock, especially in their latitudinal and local time dependences.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62930/1/nature02986.pd
Distribution and Acute Stressor-Induced Activation of Corticotrophin-Releasing Hormone Neurones in the Central Nervous System of Xenopus laevis
In mammals, corticotrophin-releasing hormone (CRH) and related peptides are known to play essential roles in the regulation of neuroendocrine, autonomic and behavioural responses to physical and emotional stress. In nonmammalian species, CRH-like peptides are hypothesized to play similar neuroendocrine and neurocrine roles. However, there is relatively little detailed information on the distribution of CRH neurones in the central nervous system (CNS) of nonmammalian vertebrates, and there are currently no comparative data on stress-induced changes in CRH neuronal physiology. We used a specific, affinity-purified antibody raised against synthetic Xenopus laevis CRH to map the distribution of CRH in the CNS of juvenile South African clawed frogs . We then analysed stress-induced changes in CRH immunoreactivity (CRH-ir) throughout the CNS. We found that CRH-positive cell bodies and fibres are widely distributed throughout the brain and rostral spinal cord of juvenile X. laevis . Strong CRH-immunoreactovity (ir) was found in cell bodies and fibres in the anterior preoptic area (POA, an area homologous to the mammalian paraventricular nucleus) and the external zone of the median eminence. Specific CRH-ir cell bodies and fibres were also identified in the septum, pallium and striatum in the telencephalon; the amygdala, bed nucleus of the stria terminalis and various hypothalamic and thalamic nuclei in the diencephalon; the tectum, torus semicircularis and tegmental nuclei of the mesencephalon; the cerebellum and locus coeruleus in the rhombencephalon; and the ventral horn of the rostral spinal cord. To determine if exposure to an acute physical stressor alters CRH neuronal physiology, we exposed juvenile frogs to shaking/handling and conducted morphometric analysis. Plasma corticosterone was significantly elevated by 30 min after exposure to the stressor and continued to increase up to 6 h. Morphometric analysis of CRH-ir after 4 h of stress showed a significant increase in CRH-ir in parvocellular neurones of the anterior preoptic area, the medial amygdala and the bed nucleus of the stria terminalis, but not in other brain regions. The stress-induced increase in CRH-ir in the POA was associated with increased Fos-like immunoreactivity (Fos-LI), and confocal microscopy showed that CRH-ir colocalized with Fos-LI in a subset of Fos-LI-positive neurones. Our results support the view that the basic pattern of CNS CRH expression arose early in vertebrate evolution and lend further support to earlier studies suggesting that amphibians may be a transitional species for descending CRH-ergic pathways. Furthermore, CRH neurones in the frog brain exhibit changes in response to a physical stressor that parallel those seen in mammals, and thus are likely to play an active role in mediating neuroendocrine, behavioural and autonomic stress responses.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73585/1/j.1365-2826.2004.01246.x.pd
ATP-Sensitive Potassium Channels Exhibit Variance in the Number of Open Channels below the Limit Predicted for Identical and Independent Gating
In small cells containing small numbers of ion channels, noise due to stochastic channel opening and closing can introduce a substantial level of variability into the cell's membrane potential. Negatively cooperative interactions that couple a channel's gating conformational change to the conformation of its neighbor(s) provide a potential mechanism for mitigating this variability, but such interactions have not previously been directly observed. Here we show that heterologously expressed ATP-sensitive potassium channels generate noise (i.e., variance in the number of open channels) below the level possible for identical and independent channels. Kinetic analysis with single-molecule resolution supports the interpretation that interchannel negative cooperativity (specifically, the presence of an open channel making a closed channel less likely to open) contributes to the decrease in noise. Functional coupling between channels may be important in modulating stochastic fluctuations in cellular signaling pathways
Behavioural activation by mental health nurses for late-life depression in primary care: a randomized controlled trial
Background: Depressive symptoms are common in older adults. The effectiveness of pharmacological treatments and the availability of psychological treatments in primary care are limited. A behavioural approach to depression treatment might be beneficial to many older adults but such care is still largely unavailable. Behavioural Activation (BA) protocols are less complicated and more easy to train than other psychological therapies, making them very suitable for delivery by less specialised therapists. The recent introduction of the mental health nurse in primary care centres in the Netherlands has created major opportunities for improving the accessibility of psychological treatments for late-life depression in primary care. BA may thus address the needs of older patients while improving treatment outcome and lowering costs.The primary objective of this study is to compare the effectiveness and cost-effectiveness of BA in comparison with treatment as usual (TAU) for late-life depression in Dutch primary care. A secondary goal is to explore several potential mechanisms of change, as well as predictors and moderators of treatment outcome of BA for late-life depression.
Methods/design: Cluster-randomised controlled multicentre trial with two parallel groups: a) behavioural activation, and b) treatment as usual, conducted in primary care centres with a follow-up of 52 weeks. The main inclusion criterion is a PHQ-9 score > 9. Patients are excluded from the trial in case of severe mental illness that requires specialized treatment, high suicide risk, drug and/or alcohol abuse, prior psychotherapy, change in dosage or type of prescribed antidepressants in the previous 12 weeks, or moderate to severe cognitive impairment. The intervention consists of 8 weekly 30-min BA sessions delivered by a trained mental health nurse.
Discussion: We expect BA to be an effective and cost-effective treatment for late-life depression compared to TAU. BA delivered by mental health nurses could increase the availability and accessibility of non-pharmacological treatments for late-life depression in primary care.
Trial registration: This study is retrospectively registered in the Dutch Clinical Trial Register NTR6013on August 25th 2016.
© 2017 The Author(s)
Gene-enhanced tissue engineering for dental hard tissue regeneration: (2) dentin-pulp and periodontal regeneration
Potential applications for gene-based tissue engineering therapies in the oral and maxillofacial complex include the delivery of growth factors for periodontal regeneration, pulp capping/dentin regeneration, and bone grafting of large osseous defects in dental and craniofacial reconstruction. Part 1 reviewed the principals of gene-enhanced tissue engineering and the techniques of introducing DNA into cells. This manuscript will review recent advances in gene-based therapies for dental hard tissue regeneration, specifically as it pertains to dentin regeneration/pulp capping and periodontal regeneration
- …