3,171 research outputs found
Refining orthologue groups at the transcript level
<p>Abstract</p> <p>Background</p> <p>Orthologues are genes in different species that are related through divergent evolution from a common ancestor and are expected to have similar functions. Many databases have been created to describe orthologous genes based on existing sequence data. However, alternative splicing (in eukaryotes) is usually disregarded in the determination of orthologue groups and the functional consequences of alternative splicing have not been considered. Most multi-exon genes can encode multiple protein isoforms which often have different functions and can be disease-related. Extending the definition of orthologue groups to take account of alternate splicing and the functional differences it causes requires further examination.</p> <p>Results</p> <p>A subset of the orthologous gene groups between human and mouse was selected from the InParanoid database for this study. Each orthologue group was divided into sub-clusters, at the transcript level, using a method based on the sequence similarity of the isoforms. Transcript based sub-clusters were verified by functional signatures of the cluster members in the InterPro database. Functional similarity was higher within than between transcript-based sub-clusters of a defined orthologous group. In certain cases, cancer-related isoforms of a gene could be distinguished from other isoforms of the gene. Predictions of intrinsic disorder in protein regions were also correlated with the isoform sub-clusters within an orthologue group.</p> <p>Conclusions</p> <p>Sub-clustering of orthologue groups at the transcript level is an important step to more accurately define functionally equivalent orthologue groups. This work appears to be the first effort to refine orthologous groupings of genes based on the consequences of alternative splicing on function. Further investigation and refinement of the methodology to classify and verify isoform sub-clusters is needed, particularly to extend the technique to more distantly related species.</p
Refining orthologue groups at the transcript level
<p>Abstract</p> <p>Background</p> <p>Orthologues are genes in different species that are related through divergent evolution from a common ancestor and are expected to have similar functions. Many databases have been created to describe orthologous genes based on existing sequence data. However, alternative splicing (in eukaryotes) is usually disregarded in the determination of orthologue groups and the functional consequences of alternative splicing have not been considered. Most multi-exon genes can encode multiple protein isoforms which often have different functions and can be disease-related. Extending the definition of orthologue groups to take account of alternate splicing and the functional differences it causes requires further examination.</p> <p>Results</p> <p>A subset of the orthologous gene groups between human and mouse was selected from the InParanoid database for this study. Each orthologue group was divided into sub-clusters, at the transcript level, using a method based on the sequence similarity of the isoforms. Transcript based sub-clusters were verified by functional signatures of the cluster members in the InterPro database. Functional similarity was higher within than between transcript-based sub-clusters of a defined orthologous group. In certain cases, cancer-related isoforms of a gene could be distinguished from other isoforms of the gene. Predictions of intrinsic disorder in protein regions were also correlated with the isoform sub-clusters within an orthologue group.</p> <p>Conclusions</p> <p>Sub-clustering of orthologue groups at the transcript level is an important step to more accurately define functionally equivalent orthologue groups. This work appears to be the first effort to refine orthologous groupings of genes based on the consequences of alternative splicing on function. Further investigation and refinement of the methodology to classify and verify isoform sub-clusters is needed, particularly to extend the technique to more distantly related species.</p
Promoter-sharing by different genes in human genome – CPNE1 and RBM12 gene pair as an example
<p>Abstract</p> <p>Background</p> <p>Regulation of gene expression plays important role in cellular functions. Co-regulation of different genes may indicate functional connection or even physical interaction between gene products. Thus analysis on genomic structures that may affect gene expression regulation could shed light on the functions of genes.</p> <p>Results</p> <p>In a whole genome analysis of alternative splicing events, we found that two distinct genes, <it>copine I </it>(<it>CPNE1</it>) and <it>RNA binding motif protein 12 </it>(<it>RBM12</it>), share the most 5' exons and therefore the promoter region in human. Further analysis identified many gene pairs in human genome that share the same promoters and 5' exons but have totally different coding sequences. Analysis of genomic and expressed sequences, either cDNAs or expressed sequence tags (ESTs) for <it>CPNE1 </it>and <it>RBM12</it>, confirmed the conservation of this phenomenon during evolutionary courses. The co-expression of the two genes initiated from the same promoter is confirmed by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) in different tissues in both human and mouse. High degrees of sequence conservation among multiple species in the 5'UTR region common to <it>CPNE1 </it>and <it>RBM12 </it>were also identified.</p> <p>Conclusion</p> <p>Promoter and 5'UTR sharing between <it>CPNE1 </it>and <it>RBM12 </it>is observed in human, mouse and zebrafish. Conservation of this genomic structure in evolutionary courses indicates potential functional interaction between the two genes. More than 20 other gene pairs in human genome were found to have the similar genomic structure in a genome-wide analysis, and it may represent a unique pattern of genomic arrangement that may affect expression regulation of the corresponding genes.</p
Patients' perceptions of the potential of breathing training for asthma: a qualitative study.
Poor symptom control is common in asthma. Breathing training exercises may be an effective adjunct to medication; it is therefore important to understand facilitators and barriers to uptake of breathing training exercises
Investigating the effect of independent blinded digital image assessment on the STOP GAP trial
Background
Blinding is the process of keeping treatment assignment hidden and is used to minimise the possibility of bias. Trials at high risk of bias have been shown to report larger treatment effects than low risk studies. In dermatology, one popular method of blinding is to have independent outcome assessors who are unaware of treatment allocation assessing the end point using digital photographs. However, this can be complex, expensive and time-consuming. The objective of this study was to compare the effect of blinded and unblinded outcome assessment on the results of the STOP GAP trial.
Methods
The STOP GAP trial compared prednisolone to ciclosporin in treating pyoderma gangrenosum. Participants’ lesions were measured at baseline and 6 weeks to calculate the primary outcome, speed of healing. Independent blinded assessors obtained measurements from digital photographs using specialist software. In addition, unblinded treating clinicians estimated lesion area by measuring length and width. The primary outcome was determined using blinded measurements where available, otherwise unblinded measurements were used (method referred to as trial measurements).
In this study, agreement between the trial and unblinded measurements was determined using the intraclass correlation coefficient (ICC). The STOP GAP primary analysis was repeated using unblinded measurements only. We introduced differential and non-differential error in unblinded measurements and investigated the effect on the STOP GAP primary analysis.
Results
86 (80%) of the 108 patients were assessed using digital images. Agreement between trial and unblinded measurements was excellent (ICC=0.92 at baseline; 0.83 at 6 weeks). There was no evidence that the results of the trial primary analysis differed according to how the primary outcome was assessed (p-value for homogeneity = 1.00).
Conclusions
Blinded digital image assessment in STOP GAP did not meaningfully alter trial conclusions compared with unblinded assessment. However, as the process brought added accuracy and credibility to the trial it was considered worthwhile.
These findings question the usefulness of digital image assessment in a trial with an objective outcome and where bias is not expected to be excessive. Further research should investigate if there are alternative, less complex ways of incorporating blinding in clinical trials
Patient-Specific Prosthetic Fingers by Remote Collaboration - A Case Study
The concealment of amputation through prosthesis usage can shield an amputee
from social stigma and help improve the emotional healing process especially at
the early stages of hand or finger loss. However, the traditional techniques in
prosthesis fabrication defy this as the patients need numerous visits to the
clinics for measurements, fitting and follow-ups. This paper presents a method
for constructing a prosthetic finger through online collaboration with the
designer. The main input from the amputee comes from the Computer Tomography
(CT) data in the region of the affected and the non-affected fingers. These
data are sent over the internet and the prosthesis is constructed using
visualization, computer-aided design and manufacturing tools. The finished
product is then shipped to the patient. A case study with a single patient
having an amputated ring finger at the proximal interphalangeal joint shows
that the proposed method has a potential to address the patient's psychosocial
concerns and minimize the exposure of the finger loss to the public.Comment: Open Access articl
Thyroid Carcinoma Metastasis to Skull with Infringement of Brain: Treatment with Radioiodine
Background: Infringement by differentiated thyroid carcinoma on the brain is rare but, when suspected, the patient deserves special attention. A patient with an enlarging metastasis of thyroid carcinoma to the skull that was impinging on the brain illustrates diagnostic and therapeutic strategies applicable to the treatment of metastatic carcinoma. Methods: A case study was performed. Computed tomography (CT) and magnetic resonance imaging (MRI) were done, serum thyroglobulin was measured, and tumor responses to thyroxine and 131I treatments were monitored. Tumor dosimetry, enabled by scintigraphy with 131I employing single photon emission tomography fused with CT (SPECT-CT), was performed. Results: The metastasis was from a follicular variant of papillary thyroid carcinoma. During thyrotropin stimulation the tumor enlarged. The tumor decreased in volume after each of two 131I therapies. Dosimetry indicated delivery of 1970 and 2870cGy to the tumor and 35 and 42cGy to the brain, respectively, in the two treatments. The patient has survived for more than 11 years since diagnosis. Conclusions: A metastasis from a follicular variant of papillary carcinoma increased in volume during hypothyroidism producing more infringement on the brain. Beyond the effects of thyroxine therapy, 131I treatments induced recession of tumor volume. In patients with metastases that concentrate 131I, dosimetry with SPECT-CT can predict absorbed doses of radiation to the tumor and to the adjacent organs and thus lay a basis for data-based decisions on 131I therapies. Therapy may induce prolonged survival in patients with metastases infringing on the brain.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78102/1/thy.2008.0426.pd
Maternal Particulate Matter Exposure Impairs Lung Health and Is Associated with Mitochondrial Damage.
Relatively little is known about the transgenerational effects of chronic maternal exposure to low-level traffic-related air pollution (TRAP) on the offspring lung health, nor are the effects of removing such exposure before pregnancy. Female BALB/c mice were exposed to PM2.5 (PM2.5, 5 µg/day) for 6 weeks before mating and during gestation and lactation; in a subgroup, PM was removed when mating started to model mothers moving to cleaner areas during pregnancy to protect their unborn child (Pre-exposure). Lung pathology was characterised in both dams and offspring. A subcohort of female offspring was also exposed to ovalbumin to model allergic airways disease. PM2.5 and Pre-exposure dams exhibited airways hyper-responsiveness (AHR) with mucus hypersecretion, increased mitochondrial reactive oxygen species (ROS) and mitochondrial dysfunction in the lungs. Female offspring from PM2.5 and Pre-exposure dams displayed AHR with increased lung inflammation and mitochondrial ROS production, while males only displayed increased lung inflammation. After the ovalbumin challenge, AHR was increased in female offspring from PM2.5 dams compared with those from control dams. Using an in vitro model, the mitochondria-targeted antioxidant MitoQ reversed mitochondrial dysfunction by PM stimulation, suggesting that the lung pathology in offspring is driven by dysfunctional mitochondria. In conclusion, chronic exposure to low doses of PM2.5 exerted transgenerational impairment on lung health
A 'resource allocator' for transcription based on a highly fragmented T7 RNA polymerase
Synthetic genetic systems share resources with the host, including machinery for transcription and translation. Phage RNA polymerases (RNAPs) decouple transcription from the host and generate high expression. However, they can exhibit toxicity and lack accessory proteins (σ factors and activators) that enable switching between different promoters and modulation of activity. Here, we show that T7 RNAP (883 amino acids) can be divided into four fragments that have to be co‐expressed to function. The DNA‐binding loop is encoded in a C‐terminal 285‐aa ‘σ fragment’, and fragments with different specificity can direct the remaining 601‐aa ‘core fragment’ to different promoters. Using these parts, we have built a resource allocator that sets the core fragment concentration, which is then shared by multiple σ fragments. Adjusting the concentration of the core fragment sets the maximum transcriptional capacity available to a synthetic system. Further, positive and negative regulation is implemented using a 67‐aa N‐terminal ‘α fragment’ and a null (inactivated) σ fragment, respectively. The α fragment can be fused to recombinant proteins to make promoters responsive to their levels. These parts provide a toolbox to allocate transcriptional resources via different schemes, which we demonstrate by building a system which adjusts promoter activity to compensate for the difference in copy number of two plasmids.United States. Office of Naval Research (N00014‐13‐1‐0074)National Institutes of Health (U.S.) (5R01GM095765)National Science Foundation (U.S.) (Synthetic Biology Engineering Research Center (SA5284‐11210))United States. Dept. of Defense (National Defense Science and Engineering Graduate Fellowship (NDSEG) Program))Hertz Foundation (Fellowship
Multi-centre parallel arm randomised controlled trial to assess the effectiveness and cost-effectiveness of a group-based cognitive behavioural approach to managing fatigue in people with multiple sclerosis
Abstract (provisional)
Background
Fatigue is one of the most commonly reported and debilitating symptoms of multiple sclerosis (MS); approximately two-thirds of people with MS consider it to be one of their three most troubling symptoms. It may limit or prevent participation in everyday activities, work, leisure, and social pursuits, reduce psychological well-being and is one of the key precipitants of early retirement. Energy effectiveness approaches have been shown to be effective in reducing MS-fatigue, increasing self-efficacy and improving quality of life. Cognitive behavioural approaches have been found to be effective for managing fatigue in other conditions, such as chronic fatigue syndrome, and more recently, in MS. The aim of this pragmatic trial is to evaluate the clinical and cost-effectiveness of a recently developed group-based fatigue management intervention (that blends cognitive behavioural and energy effectiveness approaches) compared with current local practice.
Methods
This is a multi-centre parallel arm block-randomised controlled trial (RCT) of a six session group-based fatigue management intervention, delivered by health professionals, compared with current local practice. 180 consenting adults with a confirmed diagnosis of MS and significant fatigue levels, recruited via secondary/primary care or newsletters/websites, will be randomised to receive the fatigue management intervention or current local practice. An economic evaluation will be undertaken alongside the trial. Primary outcomes are fatigue severity, self-efficacy and disease-specific quality of life. Secondary outcomes include fatigue impact, general quality of life, mood, activity patterns, and cost-effectiveness. Outcomes in those receiving the fatigue management intervention will be measured 1 week prior to, and 1, 4, and 12 months after the intervention (and at equivalent times in those receiving current local practice). A qualitative component will examine what aspects of the fatigue management intervention participants found helpful/unhelpful and barriers to change.
Discussion
This trial is the fourth stage of a research programme that has followed the Medical Research Council guidance for developing and evaluating complex interventions. What makes the intervention unique is that it blends cognitive behavioural and energy effectiveness approaches. A potential strength of the intervention is that it could be integrated into existing service delivery models as it has been designed to be delivered by staff already working with people with MS. Service users will be involved throughout this research. Trial registration: Current Controlled Trials ISRCTN7651747
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