186 research outputs found
The contribution of Alu exons to the human proteome.
BackgroundAlu elements are major contributors to lineage-specific new exons in primate and human genomes. Recent studies indicate that some Alu exons have high transcript inclusion levels or tissue-specific splicing profiles, and may play important regulatory roles in modulating mRNA degradation or translational efficiency. However, the contribution of Alu exons to the human proteome remains unclear and controversial. The prevailing view is that exons derived from young repetitive elements, such as Alu elements, are restricted to regulatory functions and have not had adequate evolutionary time to be incorporated into stable, functional proteins.ResultsWe adopt a proteotranscriptomics approach to systematically assess the contribution of Alu exons to the human proteome. Using RNA sequencing, ribosome profiling, and proteomics data from human tissues and cell lines, we provide evidence for the translational activities of Alu exons and the presence of Alu exon derived peptides in human proteins. These Alu exon peptides represent species-specific protein differences between primates and other mammals, and in certain instances between humans and closely related primates. In the case of the RNA editing enzyme ADARB1, which contains an Alu exon peptide in its catalytic domain, RNA sequencing analyses of A-to-I editing demonstrate that both the Alu exon skipping and inclusion isoforms encode active enzymes. The Alu exon derived peptide may fine tune the overall editing activity and, in limited cases, the site selectivity of ADARB1 protein products.ConclusionsOur data indicate that Alu elements have contributed to the acquisition of novel protein sequences during primate and human evolution
Induction Chemotherapy Followed by Radiotherapy versus Concurrent Chemoradiotherapy in elderly patients with nasopharyngeal carcinoma: finding from a propensity-matched analysis
Self-supervised Outdoor Scene Relighting
Outdoor scene relighting is a challenging problem that requires good
understanding of the scene geometry, illumination and albedo. Current
techniques are completely supervised, requiring high quality synthetic
renderings to train a solution. Such renderings are synthesized using priors
learned from limited data. In contrast, we propose a self-supervised approach
for relighting. Our approach is trained only on corpora of images collected
from the internet without any user-supervision. This virtually endless source
of training data allows training a general relighting solution. Our approach
first decomposes an image into its albedo, geometry and illumination. A novel
relighting is then produced by modifying the illumination parameters. Our
solution capture shadow using a dedicated shadow prediction map, and does not
rely on accurate geometry estimation. We evaluate our technique subjectively
and objectively using a new dataset with ground-truth relighting. Results show
the ability of our technique to produce photo-realistic and physically
plausible results, that generalizes to unseen scenes.Comment: Published in ECCV '20,
http://gvv.mpi-inf.mpg.de/projects/SelfRelight
Novel role for the innate immune receptor toll-like receptor 4 (TLR4) in the regulation of the wnt signaling pathway and photoreceptor apoptosis
Recent evidence has implicated innate immunity in regulating neuronal survival in the brain during stroke and other neurodegenerations. Photoreceptors are specialized light-detecting neurons in the retina that are essential for vision. In this study, we investigated the role of the innate immunity receptor TLR4 in photoreceptors. TLR4 activation by lipopolysaccharide (LPS) significantly reduced the survival of cultured mouse photoreceptors exposed to oxidative stress. With respect to mechanism, TLR4 suppressed Wnt signaling, decreased phosphorylation and activation of the Wnt receptor LRP6, and blocked the protective effect of the Wnt3a ligand. Paradoxically, TLR4 activation prior to oxidative injury protected photoreceptors, in a phenomenon known as preconditioning. Expression of TNFα and its receptors TNFR1 and TNFR2 decreased during preconditioning, and preconditioning was mimicked by TNFα antagonists, but was independent of Wnt signaling. Therefore, TLR4 is a novel regulator of photoreceptor survival that acts through the Wnt and TNFα pathways. © 2012 Yi et al
Gene encoder: a feature selection technique through unsupervised deep learning-based clustering for large gene expression data
© 2020, Springer-Verlag London Ltd., part of Springer Nature. Cancer is a severe condition of uncontrolled cell division that results in a tumor formation that spreads to other tissues of the body. Therefore, the development of new medication and treatment methods for this is in demand. Classification of microarray data plays a vital role in handling such situations. The relevant gene selection is an important step for the classification of microarray data. This work presents gene encoder, an unsupervised two-stage feature selection technique for the cancer samples’ classification. The first stage aggregates three filter methods, namely principal component analysis, correlation, and spectral-based feature selection techniques. Next, the genetic algorithm is used, which evaluates the chromosome utilizing the autoencoder-based clustering. The resultant feature subset is used for the classification task. Three classifiers, namely support vector machine, k-nearest neighbors, and random forest, are used in this work to avoid the dependency on any one classifier. Six benchmark gene expression datasets are used for the performance evaluation, and a comparison is made with four state-of-the-art related algorithms. Three sets of experiments are carried out to evaluate the proposed method. These experiments are for the evaluation of the selected features based on sample-based clustering, adjusting optimal parameters, and for selecting better performing classifier. The comparison is based on accuracy, recall, false positive rate, precision, F-measure, and entropy. The obtained results suggest better performance of the current proposal
Expression of pendrin in benign and malignant human thyroid tissues
The Pendred syndrome gene (PDS) encodes a transmembrane protein, pendrin, which is expressed in follicular thyroid cells and participates in the apical iodide transport. Pendrin expression has been studied in various thyroid neoplasms by means of immunohistochemistry (IHC), Western blot and RT–quantitative real-time PCR. The expression was related to the functional activity of the thyroid tissue. Follicular cells of normal, nodular goitre and Graves' disease tissues express pendrin at the apical pole of the thyrocytes. In follicular adenomas, pendrin was detected in cell membranes and cytoplasm simultaneously in 10 out of 15 cases. Pendrin protein was detected in 73.3 and 76.7% of the follicular (FTC) and papillary (PTC) thyroid carcinomas, respectively, where pendrin was solely localised inside the cytoplasm. An extensive intracellular immunostaining of pendrin was observed in six out of 11 (54.5%) of positive FTCs and 19 out of 23 (82%) of PTCs. Focal reactivity was detected in one follicular- and three papillary carcinomas, whereas pendrin protein was absent in three of 15 FTC and four of 30 PTC; mRNA of pendrin was detected in 92.4% of thyroid tumours. The relative mRNA expression of pendrin was lower in cancers than in normal thyroid tissues (P<0.001). The pendrin protein level was found to parallel its mRNA expression, which was not, however, related to the tumour size and tumour stage. In conclusion, pendrin is expressed in the majority of differentiated thyroid tumours with high individual variability but its targeting to the apical cell membrane is affected
Enhanced control of self-doping in halide perovskites for improved thermoelectric performance
Metal halide perovskites have emerged as promising photovoltaic materials, but, despite ultralow thermal conductivity, progress on developing them for thermoelectrics has been limited. Here, we report the thermoelectric properties of all-inorganic tin based perovskites with enhanced air stability. Fine tuning the thermoelectric properties of the films is achieved by self-doping through the oxidation of tin (ΙΙ) to tin (ΙV) in a thin surface-layer that transfers charge to the bulk. This separates the doping defects from the transport region, enabling enhanced electrical conductivity. We show that this arises due to a chlorine-rich surface layer that acts simultaneously as the source of free charges and a sacrificial layer protecting the bulk from oxidation. Moreover, we achieve a figure-of-merit (ZT) of 0.14 ± 0.01 when chlorine-doping and degree of the oxidation are optimised in tandem
Testosterone therapy delays cardiomyocyte aging via an androgen receptor-independent pathway
Pathophysiology of ANCA-Associated Small Vessel Vasculitis
Antineutrophil cytoplasmic autoantibodies (ANCAs) directed to proteinase 3 (PR3-ANCA) or myeloperoxidase (MPO-ANCA) are strongly associated with the ANCA-associated vasculitides—Wegener’s granulomatosis, microscopic polyangiitis, and Churg-Strauss syndrome. Clinical observations, including the efficacy of B-cell depletion via rituximab treatment, support—but do not prove—a pathogenic role for ANCA in the ANCA-associated vasculitides. In vitro experimental studies show that the interplay of ANCA, neutrophils, the alternative pathway of the complement system, and endothelial cells could result in lysis of the endothelium. A pathogenic role for MPO-ANCA is strongly supported by in vivo experimental studies in mice and rats, which also elucidate the pathogenic mechanisms involved in lesion development. Unfortunately, an animal model for PR3-ANCA–associated Wegener’s granulomatosis is not yet available. Here, cellular immunity appears to play a major role as well, particularly via interleukin-17–producing T cells, in line with granulomatous inflammation in the lesions. Finally, microbial factors, in particular Staphylococcus aureus and gram-negative bacteria, seem to be involved in disease induction and expression, but further studies are needed to define their precise role in disease development
Comparative efficacy and safety of the fixed versus unfixed combination of latanoprost and timolol in Chinese patients with open-angle glaucoma or ocular hypertension
<p>Abstract</p> <p>Background</p> <p>A noninferiority trial was conducted to evaluate the efficacy of a single evening dose of fixed-combination latanoprost 50 μg/mL and timolol 0.5 mg/mL (Xalacom<sup>®</sup>; LTFC), in Chinese patients with primary open-angle glaucoma (POAG) or ocular hypertension (OH) who were insufficiently controlled on β-blocker monotherapy or β-blocker-based dual therapy.</p> <p>Methods</p> <p>This 8-week, randomized, open-label, parallel-group, noninferiority study compared once-daily evening dosing of LTFC with the unfixed combination of latanoprost, one drop in the evening, and timolol, one drop in the morning (LTuFC). The primary efficacy endpoint was the mean change from baseline to week 8 in diurnal intraocular pressure (IOP; mean of 8 AM, 10 AM, 2 PM, 4 PM IOPs). LTFC was considered noninferior to LTuFC if the upper limit of the 95% confidence interval (CI) of the difference was < 1.5 mmHg (analysis of covariance).</p> <p>Results</p> <p>Baseline characteristics were similar for LTFC (N = 125; POAG, 70%; mean IOP, 25.8 mmHg) and LTuFC (N = 125; POAG, 69%; mean IOP, 26.0 mmHg). Mean diurnal IOP changes from baseline to week 8 were -8.6 mmHg with LTFC and -8.9 mmHg with LTuFC (between-treatment difference: 0.3 mmHg; 95%-CI, -0.3 to 1.0). Both treatments were well tolerated.</p> <p>Conclusions</p> <p>A single evening dose of LTFC was at least as effective as the unfixed combination of latanoprost in the PM and timolol in the AM in reducing IOP in Chinese subjects with POAG or OH whose IOP was insufficiently reduced with β-blocker monotherapy or β-blocker-based dual therapy. LTFC is an effective and well tolerated once-daily treatment for POAG and OH.</p> <p>Trial registration</p> <p>Clinicaltrials.gov registration: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00219596">NCT00219596</a></p
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