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1.
Cell ; 153(6): 1281-95, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23706625

RESUMO

Understanding the topological configurations of chromatin may reveal valuable insights into how the genome and epigenome act in concert to control cell fate during development. Here, we generate high-resolution architecture maps across seven genomic loci in embryonic stem cells and neural progenitor cells. We observe a hierarchy of 3D interactions that undergo marked reorganization at the submegabase scale during differentiation. Distinct combinations of CCCTC-binding factor (CTCF), Mediator, and cohesin show widespread enrichment in chromatin interactions at different length scales. CTCF/cohesin anchor long-range constitutive interactions that might form the topological basis for invariant subdomains. Conversely, Mediator/cohesin bridge short-range enhancer-promoter interactions within and between larger subdomains. Knockdown of Smc1 or Med12 in embryonic stem cells results in disruption of spatial architecture and downregulation of genes found in cohesin-mediated interactions. We conclude that cell-type-specific chromatin organization occurs at the submegabase scale and that architectural proteins shape the genome in hierarchical length scales.


Assuntos
Linhagem da Célula , Cromatina/metabolismo , Genoma , Proteínas Nucleares/análise , Animais , Fator de Ligação a CCCTC , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Células-Tronco Embrionárias/química , Células-Tronco Embrionárias/metabolismo , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Estudo de Associação Genômica Ampla , Complexo Mediador/genética , Complexo Mediador/metabolismo , Camundongos , Células-Tronco Neurais/química , Células-Tronco Neurais/metabolismo , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Proteínas Repressoras/metabolismo , Análise de Sequência de DNA , Coesinas
2.
Genome Res ; 34(7): 1089-1105, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38951027

RESUMO

Knowledge of locations and activities of cis-regulatory elements (CREs) is needed to decipher basic mechanisms of gene regulation and to understand the impact of genetic variants on complex traits. Previous studies identified candidate CREs (cCREs) using epigenetic features in one species, making comparisons difficult between species. In contrast, we conducted an interspecies study defining epigenetic states and identifying cCREs in blood cell types to generate regulatory maps that are comparable between species, using integrative modeling of eight epigenetic features jointly in human and mouse in our Validated Systematic Integration (VISION) Project. The resulting catalogs of cCREs are useful resources for further studies of gene regulation in blood cells, indicated by high overlap with known functional elements and strong enrichment for human genetic variants associated with blood cell phenotypes. The contribution of each epigenetic state in cCREs to gene regulation, inferred from a multivariate regression, was used to estimate epigenetic state regulatory potential (esRP) scores for each cCRE in each cell type, which were used to categorize dynamic changes in cCREs. Groups of cCREs displaying similar patterns of regulatory activity in human and mouse cell types, obtained by joint clustering on esRP scores, harbor distinctive transcription factor binding motifs that are similar between species. An interspecies comparison of cCREs revealed both conserved and species-specific patterns of epigenetic evolution. Finally, we show that comparisons of the epigenetic landscape between species can reveal elements with similar roles in regulation, even in the absence of genomic sequence alignment.


Assuntos
Epigênese Genética , Epigenoma , Especificidade da Espécie , Animais , Camundongos , Humanos , Células Sanguíneas/metabolismo , Sequências Reguladoras de Ácido Nucleico , Regulação da Expressão Gênica , Epigenômica/métodos
3.
PLoS Biol ; 22(1): e3002464, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38206904

RESUMO

Trichromacy is unique to primates among placental mammals, enabled by blue (short/S), green (medium/M), and red (long/L) cones. In humans, great apes, and Old World monkeys, cones make a poorly understood choice between M and L cone subtype fates. To determine mechanisms specifying M and L cones, we developed an approach to visualize expression of the highly similar M- and L-opsin mRNAs. M-opsin was observed before L-opsin expression during early human eye development, suggesting that M cones are generated before L cones. In adult human tissue, the early-developing central retina contained a mix of M and L cones compared to the late-developing peripheral region, which contained a high proportion of L cones. Retinoic acid (RA)-synthesizing enzymes are highly expressed early in retinal development. High RA signaling early was sufficient to promote M cone fate and suppress L cone fate in retinal organoids. Across a human population sample, natural variation in the ratios of M and L cone subtypes was associated with a noncoding polymorphism in the NR2F2 gene, a mediator of RA signaling. Our data suggest that RA promotes M cone fate early in development to generate the pattern of M and L cones across the human retina.


Assuntos
Placenta , Tretinoína , Gravidez , Adulto , Animais , Humanos , Feminino , Tretinoína/metabolismo , Placenta/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Retina/metabolismo , Opsinas/metabolismo , Opsinas de Bastonetes/genética , Primatas , Mamíferos/metabolismo
4.
Mol Cell ; 71(5): 802-815.e7, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30201095

RESUMO

Lamins are structural components of the nuclear lamina (NL) that regulate genome organization and gene expression, but the mechanism remains unclear. Using Hi-C, we show that lamins maintain proper interactions among the topologically associated chromatin domains (TADs) but not their overall architecture. Combining Hi-C with fluorescence in situ hybridization (FISH) and analyses of lamina-associated domains (LADs), we reveal that lamin loss causes expansion or detachment of specific LADs in mouse ESCs. The detached LADs disrupt 3D interactions of both LADs and interior chromatin. 4C and epigenome analyses further demonstrate that lamins maintain the active and repressive chromatin domains among different TADs. By combining these studies with transcriptome analyses, we found a significant correlation between transcription changes and the interaction changes of active and inactive chromatin domains These findings provide a foundation to further study how the nuclear periphery impacts genome organization and transcription in development and NL-associated diseases.


Assuntos
Núcleo Celular/genética , Genoma/genética , Laminas/genética , Lâmina Nuclear/genética , Animais , Cromatina/genética , Montagem e Desmontagem da Cromatina/genética , Epigenômica/métodos , Expressão Gênica/genética , Hibridização in Situ Fluorescente/métodos , Camundongos
5.
Blood ; 141(2): 168-179, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-35981565

RESUMO

The efficacy and safety of rivipansel, a predominantly E-selectin antagonist, were studied in a phase 3, randomized, controlled trial for vaso-occlusive crisis (VOC) requiring hospitalization (RESET). A total of 345 subjects (204 adults and 141 children) were randomized and 320 were treated (162 with rivipansel, 158 with placebo) with an IV loading dose, followed by up to 14 additional 12-hourly maintenance doses of rivipansel or placebo, in addition to standard care. Rivipansel was similarly administered during subsequent VOCs in the Open-label Extension (OLE) study. In the full analysis population, the median time to readiness for discharge (TTRFD), the primary end point, was not different between rivipansel and placebo (-5.7 hours, P = .79; hazard ratio, 0.97), nor were differences seen in secondary end points of time to discharge (TTD), time to discontinuation of IV opioids (TTDIVO), and cumulative IV opioid use. Mean soluble E-selectin decreased 61% from baseline after the loading dose in the rivipansel group, while remaining unchanged in the placebo group. In a post hoc analysis, early rivipansel treatment within 26.4 hours of VOC pain onset (earliest quartile of time from VOC onset to treatment) reduced median TTRFD by 56.3 hours, reduced median TTD by 41.5 hours, and reduced median TTDIVO by 50.5 hours, compared with placebo (all P < .05). A similar subgroup analysis comparing OLE early-treatment with early-treatment RESET placebo showed a reduction in TTD of 23.1 hours (P = .062) and in TTDIVO of 30.1 hours (P = .087). Timing of rivipansel administration after pain onset may be critical to achieving accelerated resolution of acute VOC. Trial Registration: Clinicaltrials.gov, NCT02187003 (RESET), NCT02433158 (OLE).


Assuntos
Anemia Falciforme , Hemoglobinopatias , Compostos Orgânicos Voláteis , Adulto , Criança , Humanos , Selectina E/uso terapêutico , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Compostos Orgânicos Voláteis/uso terapêutico , Dor/tratamento farmacológico , Dor/etiologia , Analgésicos Opioides/uso terapêutico , Método Duplo-Cego
6.
Nature ; 567(7749): 516-520, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30818324

RESUMO

The nitrogen cycle has been radically changed by human activities1. China consumes nearly one third of the world's nitrogen fertilizers. The excessive application of fertilizers2,3 and increased nitrogen discharge from livestock, domestic and industrial sources have resulted in pervasive water pollution. Quantifying a nitrogen 'boundary'4 in heterogeneous environments is important for the effective management of local water quality. Here we use a combination of water-quality observations and simulated nitrogen discharge from agricultural and other sources to estimate spatial patterns of nitrogen discharge into water bodies across China from 1955 to 2014. We find that the critical surface-water quality standard (1.0 milligrams of nitrogen per litre) was being exceeded in most provinces by the mid-1980s, and that current rates of anthropogenic nitrogen discharge (14.5 ± 3.1 megatonnes of nitrogen per year) to fresh water are about 2.7 times the estimated 'safe' nitrogen discharge threshold (5.2 ± 0.7 megatonnes of nitrogen per year). Current efforts to reduce pollution through wastewater treatment and by improving cropland nitrogen management can partially remedy this situation. Domestic wastewater treatment has helped to reduce net discharge by 0.7 ± 0.1 megatonnes in 2014, but at high monetary and energy costs. Improved cropland nitrogen management could remove another 2.3 ± 0.3 megatonnes of nitrogen per year-about 25 per cent of the excess discharge to fresh water. Successfully restoring a clean water environment in China will further require transformational changes to boost the national nutrient recycling rate from its current average of 36 per cent to about 87 per cent, which is a level typical of traditional Chinese agriculture. Although ambitious, such a high level of nitrogen recycling is technologically achievable at an estimated capital cost of approximately 100 billion US dollars and operating costs of 18-29 billion US dollars per year, and could provide co-benefits such as recycled wastewater for crop irrigation and improved environmental quality and ecosystem services.


Assuntos
Agricultura/métodos , Fertilizantes/análise , Fertilizantes/provisão & distribuição , Ciclo do Nitrogênio , Nitrogênio/análise , Nitrogênio/provisão & distribuição , Qualidade da Água/normas , Agricultura/estatística & dados numéricos , Animais , China , Ecossistema , Monitoramento Ambiental , Abastecimento de Alimentos/métodos , Abastecimento de Alimentos/estatística & dados numéricos , Humanos , Poluentes Químicos da Água/análise , Poluição da Água/análise
7.
Proc Natl Acad Sci U S A ; 119(17): e2120439119, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35412862

RESUMO

Long-duration spaceflight induces changes to the brain and cerebrospinal fluid compartments and visual acuity problems known as spaceflight-associated neuro-ocular syndrome (SANS). The clinical relevance of these changes and whether they equally affect crews of different space agencies remain unknown. We used MRI to analyze the alterations occurring in the perivascular spaces (PVS) in NASA and European Space Agency astronauts and Roscosmos cosmonauts after a 6-mo spaceflight on the International Space Station (ISS). We found increased volume of basal ganglia PVS and white matter PVS (WM-PVS) after spaceflight, which was more prominent in the NASA crew than the Roscosmos crew. Moreover, both crews demonstrated a similar degree of lateral ventricle enlargement and decreased subarachnoid space at the vertex, which was correlated with WM-PVS enlargement. As all crews experienced the same environment aboard the ISS, the differences in WM-PVS enlargement may have been due to, among other factors, differences in the use of countermeasures and high-resistive exercise regimes, which can influence brain fluid redistribution. Moreover, NASA astronauts who developed SANS had greater pre- and postflight WM-PVS volumes than those unaffected. These results provide evidence for a potential link between WM-PVS fluid and SANS.


Assuntos
Astronautas , Líquido Cefalorraquidiano , Sistema Glinfático , Voo Espacial , Transtornos da Visão , Líquido Cefalorraquidiano/diagnóstico por imagem , Sistema Glinfático/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Transtornos da Visão/líquido cefalorraquidiano , Transtornos da Visão/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
8.
Br J Haematol ; 204(5): 1811-1815, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38171355

RESUMO

Systemic light chain (AL) amyloidosis is a relapsing plasma cell disorder. Therapy is limited, particularly for triple-class refractory disease. We report the use of belantamab mafodotin, a BCMA-directed drug-antibody conjugate, for relapsed AL amyloidosis, including patients traditionally excluded from clinical trials. Thirty-one patients were reviewed, with a median of three prior lines of therapy. The median follow-up was 12 months (95% CI 4-19), and a median of five doses were delivered. The best haematological overall response rate was 71%, and the complete/very good partial response was 58%. Sixty-eight percent had keratopathy and improved in all. Belantamab mafodotin has high efficacy and good tolerability in patients with relapsed AL amyloidosis.


Assuntos
Anticorpos Monoclonais Humanizados , Amiloidose de Cadeia Leve de Imunoglobulina , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/tratamento farmacológico , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Recidiva , Idoso de 80 Anos ou mais , Resultado do Tratamento , Estudos Retrospectivos , Adulto
9.
J Am Acad Dermatol ; 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39374810

RESUMO

Prevention methods are important for patients with hand eczema (HE), especially those with risk factors. Frequent use of moisturizers is encouraged. Few drugs have been approved specifically for HE. Topical corticosteroids remain the mainstay treatment. Several new topical and systemic drugs are currently in development for HE. Dupilumab has recently been shown effective for chronic HE. Established criteria can be used to help determine causality for occupational HE, which is important for worker's compensation. The second article of this CME series discusses prevention, management, treatment and worker's compensation for HE.

10.
J Am Acad Dermatol ; 90(2): 319-327, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37879460

RESUMO

BACKGROUND: Isothiazolinones are a common cause of allergic contact dermatitis. OBJECTIVE: To examine the prevalence of positive patch test reactions to isothiazolinones from 2017-2020 and characterize isothiazolinone-allergic (Is+) patients compared with isothiazolinone nonallergic (Is-) patients. METHODS: Retrospective cross-sectional analysis of 9028 patients patch tested to methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI) 0.02% aqueous, MI 0.2% aqueous, benzisothiazolinone (BIT) 0.1% petrolatum, and/or octylisothiazolinone (OIT) 0.025% petrolatum. Prevalence, reaction strength, concurrent reactions, clinical relevance, and source of allergens were tabulated. RESULTS: In total, 21.9% (1976/9028) of patients had a positive reaction to 1 or more isothiazolinones. Positivity to MI was 14.4% (1296/9012), MCI/MI was 10.0% (903/9017), BIT was 8.6% (777/9018), and OIT was 05% (49/9028). Compared with Is-, Is+ patients were more likely to have occupational skin disease (16.5% vs 10.3%, P <.001), primary hand dermatitis (30.2% vs 19.7%, P <.001), and be >40 years (73.1% vs 61.9%, P <.001). Positive patch test reactions to >1 isothiazolinone occurred in 44.1% (871/1976) of Is+ patients. Testing solely to MCI/MI would miss 47.3% (611/1292) of MI and 60.1% (466/776) of BIT allergic reactions. LIMITATIONS: Retrospective cross-sectional study design and lack of follow-up data. CONCLUSION: Sensitization to isothiazolinones is high and concurrent sensitization to multiple isothiazolinone allergens is common.


Assuntos
Dermatite Alérgica de Contato , Dermatite Ocupacional , Tiazóis , Humanos , Estudos Transversais , Estudos Retrospectivos , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/epidemiologia , Dermatite Alérgica de Contato/etiologia , Dermatite Ocupacional/diagnóstico , Dermatite Ocupacional/epidemiologia , Dermatite Ocupacional/etiologia , Alérgenos/efeitos adversos , América do Norte , Testes do Emplastro/efeitos adversos , Vaselina , Conservantes Farmacêuticos/efeitos adversos
11.
J Phys Chem A ; 128(11): 2111-2120, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38469744

RESUMO

This study presents a comprehensive analysis of the vibrational spectra of methyl-ß-D-ribofuranoside. Employing a combination of inelastic neutron scattering, Raman, and infrared spectroscopy allows for the observation of all modes regardless of the selection rules. The experimental techniques were complemented by density functional theory computational methods using both gas-phase (Gaussian) and solid-state (CRYSTAL, CASTEP) approaches to provide an unambiguous assignment of the defining vibrational features. Two distinct structures of the molecule were identified in the unit cell, differentiated mainly by the orientation of the furanose ring O-H bonds. The low-energy region of the spectrum (<400 cm-1) is dominated by lattice vibrations and functional group rotation, while the midenergy region is dominated by out-of-plane bending motions of the furanose ring (400-900 cm-1) and by C-H bending in the methyl and methylene groups (1400-1600 cm-1). The high-energy region (>2800 cm-1) encompasses the C-H and O-H stretching modes and offers convincing evidence of at least one H-bonding interaction between the two structures of methyl-ß-D-ribofuranoside.

12.
Contact Dermatitis ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169428

RESUMO

BACKGROUND: Photoallergic contact dermatitis (PACD) is a delayed hypersensitivity reaction to allergens only in the presence of ultraviolet radiation in sunlight. Photopatch testing (PhotoPT) is necessary to confirm the diagnosis of PACD. There are few published studies of PhotoPT in North America. OBJECTIVE: To summarise the results of patients photopatch tested by members of the North American Contact Dermatitis Group (NACDG), 2009-2020. METHODS: Retrospective analysis of patient characteristics and PhotoPT results to 32 allergens on the NACDG Photopatch Test Series. RESULTS: Most of the 454 tested patients were female (70.3%), 21-60 years old (66.7%) and White (66.7%). There were a total of 119 positive photopatch tests. Sunscreen agents comprised 88.2% of those, with benzophenones responsible for over half of them. Final diagnoses included PACD in 17.2%, allergic contact dermatitis (ACD) in 44.5%, polymorphous light eruption (PMLE) in 18.9% and chronic actinic dermatitis (CAD) in 9.0% of patients. CONCLUSIONS: In 454 patients with suspected photosensitivity referred for photopatch testing in North America, approximately one-fifth had PACD. Sunscreen agents, especially benzophenones, were the most common photoallergens. Other common diagnoses included ACD, PMLE and CAD. Photopatch testing is an important tool for differentiating these conditions.

13.
Contact Dermatitis ; 91(2): 91-103, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38812248

RESUMO

Patch testing is the only clinically applicable diagnostic method for Type IV allergy. The availability of Type IV patch test (PT) allergens in Europe, however, is currently scarce. This severely compromises adequate diagnostics of contact allergy, leading to serious consequences for the affected patients. Against this background, the European Society of Contact Dermatitis (ESCD) has created a task force (TF) (i) to explore the current availability of PT substances in different member states, (ii) to highlight some of the unique characteristics of Type IV vs. other allergens and (iii) to suggest ways forward to promote and ensure availability of high-quality patch testing substances for the diagnosis of Type IV allergies throughout Europe. The suggestions of the TF on how to improve the availability of PT allergens are supported by the ESCD, the European Academy of Allergy and Clinical Immunology, and the European Academy of Dermatology and Venereology and intend to provide potential means to resolve the present medical crisis.


Assuntos
Alérgenos , Dermatite Alérgica de Contato , Dermatite Ocupacional , Testes do Emplastro , Humanos , Testes do Emplastro/métodos , Europa (Continente) , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/etiologia , Alérgenos/efeitos adversos , Dermatite Ocupacional/diagnóstico , Dermatite Ocupacional/etiologia , Sociedades Médicas , Comitês Consultivos
14.
J Dairy Sci ; 107(9): 6945-6970, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38788837

RESUMO

An economic simulation was carried out over 183 milk-producing countries to estimate the global economic impacts of 12 dairy cattle diseases and health conditions: mastitis (subclinical and clinical), lameness, paratuberculosis (Johne's disease), displaced abomasum, dystocia, metritis, milk fever, ovarian cysts, retained placenta, and ketosis (subclinical and clinical). Estimates of disease impacts on milk yield, fertility, and culling were collected from the literature, standardized, meta-analyzed using a variety of methods ranging from simple averaging to random-effects models, and adjusted for comorbidities to prevent overestimation. These comorbidity-adjusted disease impacts were then combined with a set of country-level estimates for lactational incidence or prevalence or both, herd characteristics, and price estimates within a series of Monte Carlo simulations that estimated and valued the economic losses due to these diseases. It was estimated that total annual global losses are US$65 billion (B). Subclinical ketosis, clinical mastitis, and subclinical mastitis were the costliest diseases modeled, resulting in mean annual global losses of approximately US$18B, US$13B, and US$9B, respectively. Estimated global annual losses due to clinical ketosis, displaced abomasum, dystocia, lameness, metritis, milk fever, ovarian cysts, paratuberculosis, and retained placenta were estimated to be US$0.2B, US$0.6B, US$0.6B, US$6B, US$5B, US$0.6B, US$4B, US$4B, and US$3B, respectively. Without adjustment for comorbidities, when statistical associations between diseases were disregarded, mean aggregate global losses would have been overestimated by 45%. Although annual losses were greatest in India (US$12B), the United States (US$8B), and China (US$5B), depending on the measure of losses used (losses as a percentage of gross domestic product, losses per capita, losses as a percentage of gross milk revenue), the relative economic burden of these dairy cattle diseases across countries varied markedly.


Assuntos
Doenças dos Bovinos , Indústria de Laticínios , Mastite Bovina , Bovinos , Animais , Doenças dos Bovinos/economia , Doenças dos Bovinos/epidemiologia , Feminino , Indústria de Laticínios/economia , Mastite Bovina/economia , Mastite Bovina/epidemiologia , Leite/economia , Lactação , Comorbidade , Cetose/veterinária , Cetose/economia , Gravidez
15.
J Med Philos ; 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39244778

RESUMO

It is widely held that to break a promise that one made to a person who is now dead would be to wrong her. This view undergirds many positions in bioethics, ranging from those that concern who may access a person's medical records after she has died, to questions concerning organ procurement and posthumous procreation. Ashley Dressel has argued that there is no reason to believe that promissory obligations can be owed to people who are dead. Although her arguments are unsuccessful, others establish that neither of the promissory obligation accounts that she considers (the "Authority Account" and the "harm-based view") can justify the standard view that directed posthumous promissory obligation is possible. However, this does not mean that the received view that we should keep our promises to the dead is mistaken. First, the theoretical commitments and argumentative strategies of those who endorse the possibility of posthumous promissory obligations preclude them from grounding such on either of these accounts of directed promissory obligation. They are thus already committed to justifying such obligations in other ways. Second, the obligation to keep promises to the dead could be justified on the grounds that not to do so would adversely affect the living.

16.
Genome Res ; 30(2): 299-312, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32024661

RESUMO

Current transcriptome annotations have largely relied on short read lengths intrinsic to the most widely used high-throughput cDNA sequencing technologies. For example, in the annotation of the Caenorhabditis elegans transcriptome, more than half of the transcript isoforms lack full-length support and instead rely on inference from short reads that do not span the full length of the isoform. We applied nanopore-based direct RNA sequencing to characterize the developmental polyadenylated transcriptome of C. elegans Taking advantage of long reads spanning the full length of mRNA transcripts, we provide support for 23,865 splice isoforms across 14,611 genes, without the need for computational reconstruction of gene models. Of the isoforms identified, 3452 are novel splice isoforms not present in the WormBase WS265 annotation. Furthermore, we identified 16,342 isoforms in the 3' untranslated region (3' UTR), 2640 of which are novel and do not fall within 10 bp of existing 3'-UTR data sets and annotations. Combining 3' UTRs and splice isoforms, we identified 28,858 full-length transcript isoforms. We also determined that poly(A) tail lengths of transcripts vary across development, as do the strengths of previously reported correlations between poly(A) tail length and expression level, and poly(A) tail length and 3'-UTR length. Finally, we have formatted this data as a publicly accessible track hub, enabling researchers to explore this data set easily in a genome browser.


Assuntos
Caenorhabditis elegans/genética , Genoma/genética , RNA Mensageiro/genética , Transcriptoma/genética , Processamento Alternativo/genética , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Éxons/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Anotação de Sequência Molecular , Análise de Sequência de RNA
17.
Genome Res ; 30(3): 472-484, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32132109

RESUMO

Thousands of epigenomic data sets have been generated in the past decade, but it is difficult for researchers to effectively use all the data relevant to their projects. Systematic integrative analysis can help meet this need, and the VISION project was established for validated systematic integration of epigenomic data in hematopoiesis. Here, we systematically integrated extensive data recording epigenetic features and transcriptomes from many sources, including individual laboratories and consortia, to produce a comprehensive view of the regulatory landscape of differentiating hematopoietic cell types in mouse. By using IDEAS as our integrative and discriminative epigenome annotation system, we identified and assigned epigenetic states simultaneously along chromosomes and across cell types, precisely and comprehensively. Combining nuclease accessibility and epigenetic states produced a set of more than 200,000 candidate cis-regulatory elements (cCREs) that efficiently capture enhancers and promoters. The transitions in epigenetic states of these cCREs across cell types provided insights into mechanisms of regulation, including decreases in numbers of active cCREs during differentiation of most lineages, transitions from poised to active or inactive states, and shifts in nuclease accessibility of CTCF-bound elements. Regression modeling of epigenetic states at cCREs and gene expression produced a versatile resource to improve selection of cCREs potentially regulating target genes. These resources are available from our VISION website to aid research in genomics and hematopoiesis.


Assuntos
Epigênese Genética , Hematopoese/genética , Células-Tronco Hematopoéticas/metabolismo , Animais , Camundongos , Elementos Reguladores de Transcrição , Transcriptoma
18.
Proc Biol Sci ; 290(2001): 20230640, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37357857

RESUMO

Deep-sea cephalopods are diverse, abundant, and poorly understood. The Cirrata are gelatinous finned octopods and among the deepest-living cephalopods ever recorded. Their natural feeding behaviour remains undocumented. During deep-sea surveys in the Arctic, we observed Cirroteuthis muelleri. Octopods were encountered with their web spread wide, motionless and drifting in the water column 500-2600 m from the seafloor. Individuals of C. muelleri were also repeatedly observed on the seafloor where they exhibited a repeated, behavioural sequence interpreted as feeding. The sequence (11-21 s) consisted of arm web spreading, enveloping and retreating. Prey capture happened during the enveloping phase and lasted 5-49 s. Numerous traces of feeding activity were also observed on the seafloor. The utilization of the water column for drifting and the deep seafloor for feeding is a novel migration behaviour for cephalopods, but known from gelatinous fishes and holothurians. By benthic feeding, the octopods benefit from the enhanced nutrient availability on the seafloor. Drifting in the water column may be an energetically efficient way of transportation while simultaneously avoiding seafloor-associated predators. In situ observations are indispensable to discover the behaviour of abundant megafauna, and the energetic coupling between the pelagic and benthic deep sea.


Assuntos
Almoço , Octopodiformes , Animais , Peixes , Comportamento Alimentar , Água , Ecossistema
19.
J Endovasc Ther ; : 15266028231199923, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37728000

RESUMO

PURPOSE: This study examines the use and impact of directional atherectomy with antirestenotic therapy (DAART) versus angioplasty plus Supera stent implantation on the outcomes during endovascular treatment of popliteal lesions in clinical practice. METHODS: Overall 143 consecutive patients (mean age 75.0±12.2 years, 72% male), with isolated atherosclerotic disease of the popliteal artery who underwent endovascular treatment using DAART therapy or percutaneous transluminal angioplasty (PTA)/Supera stenting of the popliteal artery between January 2016 and December 2021 were identified from a retrospectively database. Patient and plaque characteristics were collected. A propensity-score matched, case-control analysis was conducted to balance covariates between the group of patients who underwent DAART and the one treated by PTA/Supera stenting. RESULTS: A total of 51 patients (35.7%) showed severe claudication and 92 (64.3%) critical limb ischemia. There was a trend toward longer treated lesions (90.4±81 vs 72.5±5.3 mm, p=0.089) and more chronic total occlusions (60.5% vs 46.8%, p=0.058) in the PTA/Supera stenting group, although not reaching statistically significance. Moderate-to-severe calcification was present in most lesions treated (75.8% of DAART group, 80.2% of PTA/Supera stenting group, and 78.3% of total cohort). Among the 53 case-matched pairs of patients treated with DAART or PTA/Supera stenting, there were no significant differences in short-term outcomes, including rate of technical success (96.2% vs 98.1%, p=0.232), procedural success (88.7% vs 90.1%, p=0.251), distal embolization (1.9% vs 1.9%, p=0.178), dissection (5.7% vs 1.9%, p=0.268), perforation (3.8% vs 5.6%, p=0.163), hospital discharge (1.2±0.1 vs 1.0±0.1, p=0.325), 30 day minor (28.3% vs 32.1%, p=0.264) or major amputation rates (7.5% vs 3.8%, p=0.107), and 30 day mortality (1.9% vs 1.9%, p=0.173). At 1 year, there was no difference in primary patency (73.6% vs 77.4%, p=0.233), primary assisted patency (81.3% vs 84.9%, p=0.167), secondary patency (86.8% vs 92.5%, p=0.094), ipsilateral minor (35.8% vs 39.6%, p=0.472) or major amputation (9.4% vs 7.5%, p=0.186), ankle brachial index improvement (0.32±0.12 vs 0.37±0.37, p=0.401), or mortality (5.7% vs 5.7%, p=0.121) rate between patients who underwent DAART or PTA/Supera stenting for popliteal lesions. CONCLUSION: Twelve-month results following DAART technique or PTA/Supera stenting of atherosclerotic lesions of the popliteal artery are not different, regardless of patient and plaque characteristics. CLINICAL IMPACT: The DAART technique for the treatment of popliteal artery atherosclerotic disease is presented as a "leave nothing behind" strategy with on-year clinical outcomes similar to ATP/Supera stenting.

20.
Analyst ; 148(15): 3574-3583, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37403759

RESUMO

A line illumination Raman microscope extracts the underlying spatial and spectral information of a sample, typically a few hundred times faster than raster scanning. This makes it possible to measure a wide range of biological samples such as cells and tissues - that only allow modest intensity illumination to prevent potential damage - within feasible time frame. However, a non-uniform intensity distribution of laser line illumination may induce some artifacts in the data and lower the accuracy of machine learning models trained to predict sample class membership. Here, using cancerous and normal human thyroid follicular epithelial cell lines, FTC-133 and Nthy-ori 3-1 lines, whose Raman spectral difference is not so large, we show that the standard pre-processing of spectral analyses widely used for raster scanning microscopes introduced some artifacts. To address this issue, we proposed a detrending scheme based on random forest regression, a nonparametric model-free machine learning algorithm, combined with a position-dependent wavenumber calibration scheme along the illumination line. It was shown that the detrending scheme minimizes the artifactual biases arising from non-uniform laser sources and significantly enhances the differentiability of the sample states, i.e., cancerous or normal epithelial cells, compared to the standard pre-processing scheme.


Assuntos
Iluminação , Microscopia , Humanos , Luz , Calibragem , Algoritmos , Análise Espectral Raman
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