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BACKGROUND: Recent evidence suggests a beneficial effect of endovascular thrombectomy in acute ischaemic stroke with large infarct; however, previous trials have relied on multimodal brain imaging, whereas non-contrast CT is mostly used in clinical practice. METHODS: In a prospective multicentre, open-label, randomised trial, patients with acute ischaemic stroke due to large vessel occlusion in the anterior circulation and a large established infarct indicated by an Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) of 3-5 were randomly assigned using a central, web-based system (using a 1:1 ratio) to receive either endovascular thrombectomy with medical treatment or medical treatment (ie, standard of care) alone up to 12 h from stroke onset. The study was conducted in 40 hospitals in Europe and one site in Canada. The primary outcome was functional outcome across the entire range of the modified Rankin Scale at 90 days, assessed by investigators masked to treatment assignment. The primary analysis was done in the intention-to-treat population. Safety endpoints included mortality and rates of symptomatic intracranial haemorrhage and were analysed in the safety population, which included all patients based on the treatment they received. This trial is registered with ClinicalTrials.gov, NCT03094715. FINDINGS: From July 17, 2018, to Feb 21, 2023, 253 patients were randomly assigned, with 125 patients assigned to endovascular thrombectomy and 128 to medical treatment alone. The trial was stopped early for efficacy after the first pre-planned interim analysis. At 90 days, endovascular thrombectomy was associated with a shift in the distribution of scores on the modified Rankin Scale towards better outcome (adjusted common OR 2·58 [95% CI 1·60-4·15]; p=0·0001) and with lower mortality (hazard ratio 0·67 [95% CI 0·46-0·98]; p=0·038). Symptomatic intracranial haemorrhage occurred in seven (6%) patients with thrombectomy and in six (5%) with medical treatment alone. INTERPRETATION: Endovascular thrombectomy was associated with improved functional outcome and lower mortality in patients with acute ischaemic stroke from large vessel occlusion with established large infarct in a setting using non-contrast CT as the predominant imaging modality for patient selection. FUNDING: EU Horizon 2020.
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Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Estudos Prospectivos , Trombectomia/métodos , Hemorragias Intracranianas/etiologia , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Procedimentos Endovasculares/métodos , Infarto/complicações , Alberta , Resultado do TratamentoRESUMO
PURPOSE: Evaluation of water material density images (wMDIm) of dual-energy CT (DECT) for earlier prediction of final infarct volume (fiV) in follow-up single-energy CT (SECT) and correlation with clinical outcome. METHODS: Fifty patients (69 years, ± 12.1, 40-90, 50% female) with middle cerebral artery (MCA) occlusions were included. Early infarct volumes were analyzed in monoenergetic images (MonoIm) and wMDIm at 60 keV and compared with the fiV in SECT 4.9 days (± 4) after thrombectomy. Association between infarct volume and functional outcome was tested by linear regression analysis. RESULTS: wMDIm shows a prior visible infarct demarcation (60.7 ml, ± 74.9 ml) compared with the MonoIm (37.57 ml, ± 76.7 ml). Linear regression analysis, Bland-Altman plots and Pearson correlation coefficients show a close correlation of infarct volume in wMDIm to the fiV in SECT (r = 0.86; 95% CI 0.76-0.92), compared with MonoIm and SECT (r = 0.81; 95% CI 0.69-0.89). The agreement with SECT is substantially higher in patients with infarct volumes < 70 ml (n = 33; 66%). Coefficients were smaller with r = 0.59 (95% CI 0.31; 0.78) for MonoIm and SECT compared with r = 0.77 (95% CI 0.57; 0.88) for wMDIm and SECT. At admission, the mean NIHSS score and mRS were 17.02 (± 4.7) and 4.9 (± 0.2). mRS ≤ 2 was achieved in 56% at 90 days with a mean mRS of 2.5 (± 0.8) at discharge. CONCLUSION: Material decomposition allows earlier visibility of the final infarct volume. This promises an earlier evaluation of the dimension and severity of infarction and may lead to faster initiation of secondary stroke prophylaxis.
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Acidente Vascular Cerebral , Tomografia Computadorizada por Raios X , Feminino , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Masculino , TrombectomiaRESUMO
Expression of transposable elements in the germline is controlled by Piwi-interacting (pi) RNAs produced by genomic loci termed piRNA clusters and associated with Rhino, a heterochromatin protein 1 (HP1) homolog. Previously, we have shown that transgenes containing a fragment of the I retrotransposon form de novo piRNA clusters in the Drosophila germline providing suppression of I-element activity. We noted that identical transgenes located in different genomic sites vary considerably in piRNA production and classified them as "strong" and "weak" piRNA clusters. Here, we investigated what chromatin and transcriptional changes occur at the transgene insertion sites after their conversion into piRNA clusters. We found that the formation of a transgenic piRNA cluster is accompanied by activation of transcription from both genomic strands that likely initiates at multiple random sites. The chromatin of all transgene-associated piRNA clusters contain high levels of trimethylated lysine 9 of histone H3 (H3K9me3) and HP1a, whereas Rhino binding is considerably higher at the strong clusters. None of these chromatin marks was revealed at the "empty" sites before transgene insertion. Finally, we have shown that in the nucleus of polyploid nurse cells, the formation of a piRNA cluster at a given transgenic genomic copy works according to an "all-or-nothing" model: either there is high Rhino enrichment or there is no association with Rhino at all. As a result, genomic copies of a weak piRNA transgenic cluster show a mosaic association with Rhino foci, while the majority of strong transgene copies associate with Rhino and are hence involved in piRNA production.
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Cromatina/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , RNA Interferente Pequeno/genética , Transcrição Gênica/genética , Animais , Animais Geneticamente Modificados , Homólogo 5 da Proteína Cromobox , Feminino , Histonas/metabolismo , Metilação , Ligação Proteica , Retroelementos/genética , Ativação Transcricional/genética , Transgenes/genéticaRESUMO
PURPOSE: To determine the impact of vessel variation and anatomical features on technical and clinical success. MATERIALS AND METHODS: In vitro blood clots (n=100) were introduced into a silicon carotid-T flow model of 2, 3 or 4mm. The ICA/M1angle varied at 45°, 90°, 135° and 180°. Peripheral embolism was measured. In vivo 50 pat. (73.5 yrs.,±15) with MCA occlusion were examined for siphon variation, ICA morphology, vessel diameter and angles. The patients were divided according to the clinical success (mRS): group A: mRS≤2 after 90 day and group B: mRS≥3. Furthermore the technical success (TICI) and number of retrieval (n) were analysed. RESULTS: In vitro with larger vessel diameter the migrated thrombus load decreased (P=.001). The steeper the M1/ICA angles, the higher thrombus weighs (180°: 2.94mg; 135°: 6.32mg; 90°: 8.65mg, 45°: 10.69mg; P<.001). In vivo patients with mRS≤2 had significantly lower NIHSS (16.5 vs 20, P=.009) and higher ASPECTS (9 vs 6, P<.05). TICI≥2b was more often achieved (86.6 vs 40% P=.002). The procedure time was lower (45 vs. 80min, P<.05) with smaller number of retrieval (1.5 vs 4, P<05). Proximal ICA stenosis offers a trend to unfavourable outcome (P=.073). Siphon variation "D" is associated with less retrieval manoeuvre. CONCLUSION: While in vitro there is a close correlation between embolism and vascular anatomy, in vivo carotid artery stenosis and siphon variation influence clinical and technical success.
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Artéria Cerebral Anterior/patologia , Artéria Carótida Interna/patologia , Infarto da Artéria Cerebral Média/terapia , Trombólise Mecânica/métodos , Artéria Cerebral Média/patologia , Idoso , Artéria Cerebral Anterior/fisiopatologia , Artéria Carótida Interna/fisiopatologia , Estenose das Carótidas/patologia , Estenose das Carótidas/terapia , Feminino , Humanos , Infarto da Artéria Cerebral Média/patologia , Masculino , Artéria Cerebral Média/fisiopatologia , Modelos Biológicos , Trombose , Resultado do TratamentoRESUMO
Most of our understanding of Drosophila heterochromatin structure and evolution has come from the annotation of heterochromatin from the isogenic y; cn bw sp strain. However, almost nothing is known about the heterochromatin's structural dynamics and evolution. Here, we focus on a 180-kb heterochromatic locus producing Piwi-interacting RNAs (piRNA cluster), the flamenco (flam) locus, known to be responsible for the control of at least three transposable elements (TEs). We report its detailed structure in three different Drosophila lines chosen according to their capacity to repress or not to repress the expression of two retrotransposons named ZAM and Idefix, and we show that they display high structural diversity. Numerous rearrangements due to homologous and nonhomologous recombination, deletions and segmental duplications, and loss and gain of TEs are diverse sources of active genomic variation at this locus. Notably, we evidence a correlation between the presence of ZAM and Idefix in this piRNA cluster and their silencing. They are absent from flam in the strain where they are derepressed. We show that, unexpectedly, more than half of the flam locus results from recent TE insertions and that most of the elements concerned are prone to horizontal transfer between species of the melanogaster subgroup. We build a model showing how such high and constant dynamics of a piRNA master locus open the way to continual emergence of new patterns of piRNA biogenesis leading to changes in the level of transposition control.
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Caderinas/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Evolução Molecular , Variação Genética , Heterocromatina/genética , RNA Interferente Pequeno/genética , Retroelementos/genética , Animais , Sequência de Bases , Biologia Computacional , Transferência Genética Horizontal/genética , Dados de Sequência Molecular , Oligonucleotídeos/genética , Interferência de RNA , Alinhamento de Sequência , Análise de Sequência de DNARESUMO
PURPOSE: To assess the effectiveness, technical aspects, handling, and safety of the micromesh Roadsaver Carotid Artery Stent in the treatment of atherosclerotic carotid artery stenosis and tandem lesions in ischemic stroke patients. METHODS: Seven patients (5 men; mean age 75±11.4 years, range 53-86) suffering from symptomatic internal carotid artery (ICA) stenosis (mean 76% diameter reduction) were treated with the dual layer closed-cell stent without embolic protection. Postdilation was performed in 6 of 7 patients. Two patients were treated in the context of ischemic stroke and concurrent middle cerebral artery occlusion. Mean National Institutes of Health Stroke Scale score at admission was 12.8±5. RESULTS: All devices were deployed satisfactorily. One wall-adherent thromboembolus in a proximal ICA was covered with the Roadsaver stent in a tandem lesion setting. The modified Rankin Scale (mRS) declined from 3.7±0.7 to 2.4±0.8 in hospital, showing an improvement in clinical symptoms. No complications were detected during or after the procedure. The 30-day mRS was 1.7±1.1. At 6 months, ultrasound examination demonstrated patency of stents and the external carotid arteries. CONCLUSION: The Roadsaver double layer micromesh stent seems to be safe and effective in the treatment of extracranial ICA stenosis and in the context of tandem lesions in ischemic stroke. Further studies with larger populations are warranted.
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Angioplastia com Balão/instrumentação , Artéria Carótida Interna , Estenose das Carótidas/terapia , Stents , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/fisiopatologia , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/fisiopatologia , Feminino , Humanos , Infarto da Artéria Cerebral Média/etiologia , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Radiografia , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia Doppler em Cores , Grau de Desobstrução VascularRESUMO
PIWI-interacting RNAs (piRNAs) provide defence against transposable element (TE) expansion in the germ line of metazoans. piRNAs are processed from the transcripts encoded by specialized heterochromatic clusters enriched in damaged copies of transposons. How these regions are recognized as a source of piRNAs is still elusive. The aim of this study is to determine how transgenes that contain a fragment of the Long Interspersed Nuclear Elements (LINE)-like I transposon lead to an acquired TE resistance in Drosophila. We show that such transgenes, being inserted in unique euchromatic regions that normally do not produce small RNAs, become de novo bidirectional piRNA clusters that silence I-element activity in the germ line. Strikingly, small RNAs of both polarities are generated from the entire transgene and flanking genomic sequences--not only from the transposon fragment. Chromatin immunoprecipitation analysis shows that in ovaries, the trimethylated histone 3 lysine 9 (H3K9me3) mark associates with transgenes producing piRNAs. We show that transgene-derived hsp70 piRNAs stimulate in trans cleavage of cognate endogenous transcripts with subsequent processing of the non-homologous parts of these transcripts into piRNAs.
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Drosophila/genética , Elementos Nucleotídeos Longos e Dispersos , RNA Interferente Pequeno/biossíntese , Transgenes , Animais , Cromatina/metabolismo , Feminino , Proteínas de Choque Térmico HSP70/genética , Ovário/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Sequências Repetidas TerminaisRESUMO
BACKGROUND: Long-term data showing the benefits of endovascular thrombectomy for stroke with large infarct are scarce. The TENSION trial showed the safety and efficacy of endovascular thrombectomy in patients with ischaemic stroke and large infarct at 90 days. We aimed to investigate the safety and efficacy at 12 months of endovascular thrombectomy in patients who were enrolled in the TENSION trial. METHODS: TENSION was an open-label, blinded endpoint, randomised trial done at 40 hospitals across Europe and one hospital in Canada. We included patients (aged ≥18 years) with acute ischaemic stroke due to large vessel occlusion in the anterior circulation and who had a large infarct, as indicated by an Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) of 3-5 on standard-of-care stroke imaging. We randomly assigned patients (1:1) to receive either endovascular thrombectomy with medical treatment or medical treatment only up to 12 h from stroke onset. The primary outcome was functional outcome across the entire range of the modified Rankin Scale at 90 days. Here, we report the prespecified 12-month follow-up analyses for functional outcome (using the simplified modified Rankin Scale questionnaire), quality of life (using the Patient-Reported Outcomes Measurement Information System 10-item [PROMIS-10] and EQ-5D questionnaires), post-stroke anxiety and depression (using the Patient Health Questionnaire-4 [PHQ-4]), and overall survival. Outcomes (except survival) were assessed in the intention-to-treat population; the survival analysis was based on treatment received. This trial is registered with ClinicalTrials.gov, NCT03094715, and is completed. FINDINGS: We enrolled patients between July 17, 2018, and Feb 21, 2023, when the trial was stopped early for efficacy. 253 patients were randomly assigned, 125 (49%) to endovascular thrombectomy and 128 (51%) to medical treatment only. Median follow-up was 8·36 months (IQR 0·02-12·00). Endovascular thrombectomy was associated with a shift in the distribution of scores on the modified Rankin Scale towards better functional outcome at 12 months (adjusted common odds ratio 2·39 [95% CI 1·47-3·90]). Endovascular thrombectomy was also associated with a better quality of life compared with medical treatment only, as reflected by median scores on the EQ-5D questionnaire index (0·7 [IQR 0·4-0·9] vs 0·4 [0·2-0·7]), median scores for health status on the EQ-5D questionnaire visual analogue scale (50 [IQR 35-70] vs 30 [5-60]), and median global physical health scores on the PROMIS-10 questionnaire (T-score 39·8 [IQR 37·4-50·8] vs 37·4 [32·4-44·9]); although there was not enough evidence to suggest a difference between groups in global mental health scores on PROMIS-10 (41·1 [IQR 36·3-48·3] vs 38·8 [31·3-44·7]) or the numbers of patients reporting anxiety (13 [22%] of 58 vs 15 [42%] of 36) and depression (18 [31%] vs 18 [50%]) on PHQ-4. Overall survival was slightly better in the endovascular thrombectomy group compared with medical treatment only (adjusted hazard ratio 0·70 [95% CI 0·50-0·99]). INTERPRETATION: In patients with acute ischaemic stroke from large vessel occlusion with established large infarct, compared with medical treatment only, endovascular thrombectomy was associated at 12 months after stroke with better functional outcome, quality of life, and overall survival. These findings suggest that the benefits of endovascular thrombectomy in patients with an ischaemic stroke and a large infarct are sustained in the long term and support the use of endovascular thrombectomy in these patients. FUNDING: European Union Horizon 2020 Research and Innovation Programme.
Assuntos
Procedimentos Endovasculares , AVC Isquêmico , Trombectomia , Humanos , Trombectomia/métodos , Masculino , Feminino , Procedimentos Endovasculares/métodos , Idoso , AVC Isquêmico/cirurgia , AVC Isquêmico/terapia , Pessoa de Meia-Idade , Resultado do Tratamento , Qualidade de Vida , Idoso de 80 Anos ou maisRESUMO
Most Drosophila transposable elements are LTR retrotransposons, some of which belong to the genus Errantivirus and share structural and functional characteristics with vertebrate endogenous retroviruses. Like endogenous retroviruses, it is unclear whether errantiviruses retain some infectivity and transposition capacity. We created conditions where control of the Drosophila ZAM errantivirus through the piRNA pathway was abolished leading to its de novo reactivation in somatic gonadal cells. After reactivation, ZAM invaded the oocytes and severe fertility defects were observed. While ZAM expression persists in the somatic gonadal cells, the germline then set up its own adaptive genomic immune response by producing piRNAs against the constantly invading errantivirus, restricting invasion. Our results suggest that although errantiviruses are continuously repressed by the piRNA pathway, they may retain their ability to infect the germline and transpose, thus allowing them to efficiently invade the germline if they are expressed.
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Proteínas de Drosophila , Retrovirus Endógenos , Animais , Feminino , Drosophila/genética , Drosophila/metabolismo , Ovário/metabolismo , Drosophila melanogaster/genética , Células Germinativas/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Retrovirus Endógenos/genética , Retrovirus Endógenos/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Elementos de DNA Transponíveis/genéticaRESUMO
Transposable elements (TEs) are mobile DNA sequences that can jump from one genomic locus to another and that have colonized the genomes of all living organisms. TE mobilization and accumulation are an important source of genomic innovations that greatly contribute to the host species evolution. To ensure their maintenance and amplification, TE transposition must occur in the germ cell genome. As TE transposition is also a major threat to genome integrity, the outcome of TE mobility in germ cell genomes could be highly dangerous because such mutations are inheritable. Thus, organisms have developed specialized strategies to protect the genome integrity from TE transposition, particularly in germ cells. Such effective TE silencing, together with ongoing mutations and negative selection, should result in the complete elimination of functional TEs from genomes. However, TEs have developed efficient strategies for their maintenance and spreading in populations, particularly by using horizontal transfer to invade the genome of novel species. Here, we discuss how TEs manage to bypass the host's silencing machineries to propagate in its genome and how hosts engage in a fightback against TE invasion and propagation. This shows how TEs and their hosts have been evolving together to achieve a fine balance between transposition and repression.
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For the treatment of peripheral arterial disease, drug-eluting technology is a widely accepted therapeutic option, with significant reduction in intimal hyperplasia and, consequently, use of target lesion revascularization. Nevertheless, the reputation of such devices was damaged after a meta-analysis, published in December 2018, showed increased mortality in patients receiving paclitaxel-eluting devices. Although subsequent studies have failed to establish such correlation, the use of paclitaxel-eluting devices remains heavily restricted. As such, other options and drugs have been developed, for instance sirolimus. In this article we present the available data on drug-eluting technology.
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PIWI-interacting RNAs (piRNAs) target transcripts by sequence complementarity serving as guides for RNA slicing in animal germ cells. The piRNA pathway is increasingly recognized as critical for essential cellular functions such as germline development and reproduction. In the Anopheles gambiae ovary, as much as 11% of piRNAs map to protein-coding genes. Here, we show that ovarian mRNAs and long non-coding RNAs (lncRNAs) are processed into piRNAs that can direct other transcripts into the piRNA biogenesis pathway. Targeting piRNAs fuel transcripts either into the ping-pong cycle of piRNA amplification or into the machinery of phased piRNA biogenesis, thereby creating networks of inter-regulating transcripts. RNAs of the same network share related genomic repeats. These repeats give rise to piRNAs, which target other transcripts and lead to a cascade of concerted RNA slicing. While ping-pong networks are based on repeats of several hundred nucleotides, networks that rely on phased piRNA biogenesis operate through short ~40-nucleotides long repeats, which we named snetDNAs. Interestingly, snetDNAs are recurring in evolution from insects to mammals. Our study brings to light a new type of conserved regulatory pathway, the snetDNA-pathway, by which short sequences can include independent genes and lncRNAs in the same biological pathway.
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Anopheles/genética , Anopheles/metabolismo , RNA Longo não Codificante/genética , RNA Interferente Pequeno/biossíntese , RNA Interferente Pequeno/genética , Aedes/genética , Aedes/metabolismo , Animais , Sequência Consenso , Sequência Conservada , DNA/genética , Elementos de DNA Transponíveis , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Evolução Molecular , Feminino , Redes Reguladoras de Genes , Genes de Insetos , Genoma de Inseto , Humanos , Masculino , Camundongos , Anotação de Sequência Molecular , Ovário/metabolismo , Sequências Repetitivas de Ácido Nucleico , Testículo/metabolismoRESUMO
Transgenes containing a fragment of the I retrotransposon represent a powerful model of piRNA cluster de novo formation in the Drosophila germline. We revealed that the same transgenes located at different genomic loci form piRNA clusters with various capacity of small RNA production. Transgenic piRNA clusters are not established in piRNA pathway mutants. However, in the wild-type context, the endogenous ancestral I-related piRNAs heterochromatinize and convert the I-containing transgenes into piRNA-producing loci. Here, we address how the quantitative level of piRNAs influences the heterochromatinization and piRNA production. We show that a minimal amount of maternal piRNAs from ancestral I-elements is sufficient to form the transgenic piRNA clusters. Supplemental piRNAs stemming from active I-element copies do not stimulate additional chromatin changes or piRNA production from transgenes. Therefore, chromatin changes and piRNA production are initiated by a minimum threshold level of complementary piRNAs, suggesting a selective advantage of prompt cell response to the lowest level of piRNAs. It is noteworthy that the weak piRNA clusters do not transform into strong ones after being targeted by abundant I-specific piRNAs, indicating the importance of the genomic context for piRNA cluster establishment. Analysis of ovarian transcription profiles suggests that regions facilitating convergent transcription favor the formation of transgenic piRNA clusters.
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Proteínas Argonautas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , RNA/biossíntese , RNA/genética , Animais , Proteínas Argonautas/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Epigênese Genética , Células Germinativas , Heterocromatina/genética , Heterocromatina/metabolismo , RNA/metabolismo , Retroelementos , TransgenesRESUMO
BACKGROUND: For species survival, the germline must faithfully transmit genetic information to the progeny. Transposable elements (TEs) constitute a significant threat to genome stability due to their mobility. In the metazoan germline, their mobilization is limited by a class of small RNAs called PIWI-interacting RNAs (piRNAs) produced by dedicated genomic loci called piRNA clusters. Although the piRNA pathway is an adaptive genomic immunity system, it remains unclear how the germline gains protection from a new transposon invasion. RESULTS: To address this question, we analyze Drosophila melanogaster lines harboring a deletion within flamenco, a major piRNA cluster specifically expressed in somatic follicular cells. This deletion leads to derepression of the retrotransposon ZAM in the somatic follicular cells and subsequent germline genome invasion. In this mutant line, we identify de novo production of sense and antisense ZAM-derived piRNAs that display a germinal molecular signature. These piRNAs originated from a new ZAM insertion into a germline dual-strand piRNA cluster and silence ZAM expression specifically in germ cells. Finally, we find that ZAM trapping in a germinal piRNA cluster is a frequent event that occurs early during the isolation of the mutant line. CONCLUSIONS: Transposons can hijack the host developmental process to propagate whenever their silencing is lost. Here, we show that the germline can protect itself by trapping invading somatic-specific TEs into germline piRNA clusters. This is the first demonstration of "auto-immunization" of a germline endangered by mobilization of a surrounding somatic TE.
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RNA Interferente Pequeno/metabolismo , Retroelementos , Animais , Drosophila melanogaster , Feminino , Ovário/metabolismoRESUMO
BACKGROUND: The field of small RNA is one of the most investigated research areas since they were shown to regulate transposable elements and gene expression and play essential roles in fundamental biological processes. Small RNA deep sequencing (sRNA-seq) is now routinely used for large-scale analyses of small RNA. Such high-throughput sequencing typically produces several millions reads. RESULTS: Here we present a computational pipeline (sRNAPipe: small RNA pipeline) based on the Galaxy framework that takes as input a fastq file of small RNA-seq reads and performs successive steps of mapping to categories of genomic sequences: transposable elements, gene transcripts, microRNAs, small nuclear RNAs, ribosomal RNAs and transfer RNAs. It also provides individual mapping and counting for chromosomes, transposable elements and gene transcripts, normalization, small RNA length analysis and plotting of the data along genomic coordinates to build publication-quality graphs and figures. sRNAPipe evaluates 10-nucleotide 5'-overlaps of reads on opposite strands to test ping-pong amplification for putative PIWI-interacting RNAs, providing counts of overlaps and corresponding z-scores. CONCLUSIONS: sRNAPipe is easy to use and does not require command-line or coding knowledge. This pipeline gives quick visual and quantitative results, which are usable for publications. sRNAPipe is freely available as a Galaxy tool and via GitHub.
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Endovascular options are increasingly recognized as primary treatments for lower extremity peripheral arterial disease inadequately responsive to noninvasive therapy. Options include balloon angioplasty and stent implantation, and newer technologies incorporate drug coatings to prevent restenosis and reduce the need for reintervention. The Eluvia drug-eluting vascular stent system (Boston Scientific, MA, USA) was designed with a biocompatible fluoropolymer coating to allow for drug elution over time. Initial clinical results demonstrate promising efficacy in terms of sustained femoropopliteal artery patency along with a good safety profile. This review summarizes the existing clinical literature on treatment of femoropopliteal artery lesions with Eluvia, and outlines the continuing research program.
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Stents Farmacológicos , Procedimentos Endovasculares/métodos , Artéria Femoral , Doença Arterial Periférica/cirurgia , Artéria Poplítea , Humanos , Desenho de PróteseRESUMO
Visual search is faster and more accurate when a subset of distractors is presented before the display containing the target. This "preview benefit" has been attributed to separate inhibitory and facilitatory guidance mechanisms during search. In the preview task the temporal cues thought to elicit inhibition and facilitation provide complementary sources of information about the likely location of the target. In this study, we use a Bayesian observer model to compare sensitivity when the temporal cues eliciting inhibition and facilitation produce complementary, and competing, sources of information. Observers searched for T-shaped targets among L-shaped distractors in 2 standard and 2 preview conditions. In the standard conditions, all the objects in the display appeared at the same time. In the preview conditions, the initial subset of distractors either stayed on the screen or disappeared before the onset of the search display, which contained the target when present. In the latter, the synchronous onset of old and new objects negates the predictive utility of stimulus-driven capture during search. The results indicate observers combine memory-driven inhibition and sensory-driven capture to reduce spatial uncertainty about the target's likely location during search. In the absence of spatially predictive onsets, memory-driven inhibition at old locations persists despite irrelevant sensory change at previewed locations. This result is consistent with a bias toward unattended objects during search via the active suppression of irrelevant capture at previously attended locations. (PsycINFO Database Record
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Atenção/fisiologia , Inibição Psicológica , Memória de Curto Prazo/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Having evolved at a rapid pace, the therapy options for percutaneous treatment of peripheral arterial disease in the lower limbs, especially percutaneous transluminal angioplasty in combination with stent-technology, are able to deliver a rate where at least 80% of the treated patients remain free from reintervention after the first years under ideal study conditions, meaning that defined and often restrict in- and exclusion criteria were fulfilled and mid-term dual platelet therapy is warranted. This is somewhat a huge leap when compared to the 50-60% in the 1980s and 1990s, but we now face an era of an increasingly demanding clientele, where the industry also strives to cover this final 20% with newer technologies. As recent studies with drug-eluting stents (DES) suggests, nowadays it is possible to achieve up to 90% patency in the short- and mid-term, but this comes accompanied by remarkably increased therapy costs, making it almost impossible to most centers to implant it as the standard therapy option. Trying to fill this gap between the low-patency of the plain old balloon angioplasty and the higher costs of the DES, drug-coated balloon technology has found its niche, knowing that reimbursement shows a broad variation across the countries and continents.