233 research outputs found

    Characterization of a Novel Association between Two Trypanosome-Specific Proteins and 5S rRNA

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    P34 and P37 are two previously identified RNA binding proteins in the flagellate protozoan Trypanosoma brucei. RNA interference studies have determined that the proteins are essential and are involved in ribosome biogenesis. Here, we show that these proteins interact in vitro with the 5S rRNA with nearly identical binding characteristics in the absence of other cellular factors. The T. brucei 5S rRNA has a complex secondary structure and presents four accessible loops (A to D) for interactions with RNA-binding proteins. In other eukaryotes, loop C is bound by the L5 ribosomal protein and loop A mainly by TFIIIA. The binding of P34 and P37 to T. brucei 5S rRNA involves the LoopA region of the RNA, but these proteins also protect the L5 binding site located on LoopC

    The Trypanosoma cruzi nucleic acid binding protein Tc38 presents changes in the intramitochondrial distribution during the cell cycle

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    Background: Tc38 of Trypanosoma cruzi has been isolated as a single stranded DNA binding protein with high specificity for the poly [dT-dG] sequence. It is present only in Kinetoplastidae protozoa and its sequence lacks homology to known functional domains. Tc38 orthologues present in Trypanosoma brucei and Leishmania were proposed to participate in quite different cellular processes. To further understand the function of this protein in Trypanosoma cruzi, we examined its in vitro binding to biologically relevant [dT-dG] enriched sequences, its expression and subcellular localization during the cell cycle and through the parasite life stages.Results: By using specific antibodies, we found that Tc38 protein from epimastigote extracts participates in complexes with the poly [dT-dG] probe as well as with the universal minicircle sequence (UMS), a related repeated sequence found in maxicircle DNA, and the telomeric repeat. However, we found that Tc38 predominantly localizes into the mitochondrion. Though Tc38 is constitutively expressed through non-replicating and replicating life stages of T. cruzi, its subcellular localization in the unique parasite mitochondrion changes according to the cell cycle stage. in epimastigotes, Tc38 is found only in association with kDNA in G1 phase. From the S to G2 phase the protein localizes in two defined and connected spots flanking the kDNA. These spots disappear in late G2 turning into a diffuse dotted signal which extends beyond the kinetoplast. This later pattern is more evident in mitosis and cytokinesis. Finally, late in cytokinesis Tc38 reacquires its association with the kinetoplast. in non-replicating parasite stages such as trypomastigotes, the protein is found only surrounding the entire kinetoplast structure.Conclusions: the dynamics of Tc38 subcellular localization observed during the cell cycle and life stages support a major role for Tc38 related to kDNA replication and maintenance.FIRCAFondo Clemente Estable (DICyT)FAPESConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)PROSULPEDECIBAAMSUD-PasteurFac Ciencias, Lab Interacc Mol, Montevideo, UruguayFac Med, Dept Genet, Montevideo, UruguayFac Ciencias, Dept Biol Celular & Mol, Montevideo, UruguayInst Invest Biol Clemente Estable Montevideo Urug, Dept Neurobiol Celular & Mol, Montevideo, UruguayUniv Nacl Gen San Martin, CONICET, INTECH, Inst Invest Biotecnol, Buenos Aires, DF, ArgentinaUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilSUNY Buffalo, Dept Microbiol & Immunol, Buffalo, NY 14260 USAInst Biol Mol Parana, Curitiba, Parana, BrazilUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilFIRCA: R03 TW05665-01Fondo Clemente Estable (DICyT): 7109Web of Scienc

    Distance-dependent association of affect with pacing strategy in cycling time trials.

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    The psychological construct of affect is proposed to significantly contribute to pacing decisions during exercise. Borg’s RPE scale, another important regulator of work rate, is criticized as an inadequate measure of the multiple perceptual responses experienced. This study aimed to examine power output distribution and associated changes in affect, self-efficacy, perceptual cues, HR, and respiratory gases during both 16.1- and 40-km self-paced cycling time trials (TT). Secondly, the differentiation between physical perceptions of exertion and sense of effort in self-paced exercise was investigated. Method: Fifteen trained male cyclists completed 16.1- and 40-km TT using a CompuTrainer cycle ergometer. Time, power output distribution, affect, self-efficacy, physical RPE (P-RPE), task effort and awareness (TEA), HR, and respiratory gases were measured throughout each TT. Linear mixed models explored associations of these variables with power output distribution and the relationship between P-RPE and TEA. Results: Similar pacing strategies were adopted in the 16.1- and 40-km TT (P = 0.31), and the main effects were found for affect (P = 0.001) and RER (P G 0.001). Interactions between affect (P = 0.037) and RER (P = 0.004), with condition, indicated closer associations with power output distribution in 16.1 km than that in 40 km TT. P-RPE was not significantly different from TEA (P = 0.053). Conclusion: A significant association between affect and power output distribution suggests that affective responses are task dependent even in self-paced exercise, and a greater association is demonstrated in higher intensity, 16.1 km TT. Furthermore, physical perceptions of exertion are not clearly differentiated from the sense of effort in self-paced exercise

    Guidelines on the diagnosis, clinical assessments, treatment and management for CLN2 disease patients

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    Background: CLN2 disease (Neuronal Ceroid Lipofuscinosis Type 2) is an ultra-rare, neurodegenerative lysosomal storage disease, caused by an enzyme deficiency of tripeptidyl peptidase 1 (TPP1). Lack of disease awareness and the non-specificity of presenting symptoms often leads to delayed diagnosis. These guidelines provide robust evidence-based, expert-agreed recommendations on the risks/benefits of disease-modifying treatments and the medical interventions used to manage this condition. Methods: An expert mapping tool process was developed ranking multidisciplinary professionals, with knowledge of CLN2 disease, diagnostic or management experience of CLN2 disease, or family support professionals. Individuals were sequentially approached to identify two chairs, ensuring that the process was transparent and unbiased. A systematic literature review of published evidence using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance was independently and simultaneously conducted to develop key statements based upon the strength of the publications. Clinical care statements formed the basis of an international modified Delphi consensus determination process using the virtual meeting (Within3) online platform which requested experts to agree or disagree with any changes. Statements reaching the consensus mark became the guiding statements within this manuscript, which were subsequently assessed against the Appraisal of Guidelines for Research and Evaluation (AGREEII) criteria. Results: Twenty-one international experts from 7 different specialities, including a patient advocate, were identified. Fifty-three guideline statements were developed covering 13 domains: General Description and Statements, Diagnostics, Clinical Recommendations and Management, Assessments, Interventions and Treatment, Additional Care Considerations, Social Care Considerations, Pain Management, Epilepsy / Seizures, Nutritional Care Interventions, Respiratory Health, Sleep and Rest, and End of Life Care. Consensus was reached after a single round of voting, with one exception which was revised, and agreed by 100% of the SC and achieved 80% consensus in the second voting round. The overall AGREE II assessment score obtained for the development of the guidelines was 5.7 (where 1 represents the lowest quality, and 7 represents the highest quality). Conclusion: This program provides robust evidence- and consensus-driven guidelines that can be used by all healthcare professionals involved in the management of patients with CLN2 disease and other neurodegenerative disorders. This addresses the clinical need to complement other information available

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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    Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts

    Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

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    Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN

    Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

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    This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin

    Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

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    Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment

    Study protocol for Women of Color and Asthma Control: A randomized controlled trial of an asthma-management intervention for African American women

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    <p>Abstract</p> <p>Background</p> <p>Among adults in the United States, asthma prevalence is disproportionately high among African American women; this group also experiences the highest levels of asthma-linked mortality and asthma-related health care utilization. Factors linked to biological sex (e.g., hormonal fluctuations), gender roles (e.g., exposure to certain triggers) and race (e.g., inadequate access to care) all contribute to the excess asthma burden in this group, and also shape the context within which African American women manage their condition. No prior interventions for improving asthma self-management have specifically targeted this vulnerable group of asthma patients. The current study aims to evaluate the efficacy of a culturally- and gender-relevant asthma-management intervention among African American women.</p> <p>Methods/Design</p> <p>A randomized controlled trial will be used to compare a five-session asthma-management intervention with usual care. This intervention is delivered over the telephone by a trained health educator. Intervention content is informed by the principles of self-regulation for disease management, and all program activities and materials are designed to be responsive to the specific needs of African American women. We will recruit 420 female participants who self-identify as African American, and who have seen a clinician for persistent asthma in the last year. Half of these will receive the intervention. The primary outcomes, upon which the target sample size is based, are number of asthma-related emergency department visits and overnight hospitalizations in the last 12 months. We will also assess the effect of the intervention on asthma symptoms and asthma-related quality of life. Data will be collected via telephone survey and medical record review at baseline, and 12 and 24 months from baseline.</p> <p>Discussion</p> <p>We seek to decrease asthma-related health care utilization and improve asthma-related quality of life in African American women with asthma, by offering them a culturally- and gender-relevant program to enhance asthma management. The results of this study will provide important information about the feasibility and value of this program in helping to address persistent racial and gender disparities in asthma outcomes.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01117805">NCT01117805</a></p
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