Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 59
Filtrar
1.
Nucleic Acids Res ; 51(8): 3934-3949, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36912080

RESUMO

The RNA exosome is an essential 3' to 5' exoribonuclease complex that mediates degradation, processing and quality control of virtually all eukaryotic RNAs. The nucleolar RNA exosome, consisting of a nine-subunit core and a distributive 3' to 5' exonuclease EXOSC10, plays a critical role in processing and degrading nucleolar RNAs, including pre-rRNA. However, how the RNA exosome is regulated in the nucleolus is poorly understood. Here, we report that the nucleolar ubiquitin-specific protease USP36 is a novel regulator of the nucleolar RNA exosome. USP36 binds to the RNA exosome through direct interaction with EXOSC10 in the nucleolus. Interestingly, USP36 does not significantly regulate the levels of EXOSC10 and other tested exosome subunits. Instead, it mediates EXOSC10 SUMOylation at lysine (K) 583. Mutating K583 impaired the binding of EXOSC10 to pre-rRNAs, and the K583R mutant failed to rescue the defects in rRNA processing and cell growth inhibition caused by knockdown of endogenous EXOSC10. Furthermore, EXOSC10 SUMOylation is markedly reduced in cells in response to perturbation of ribosomal biogenesis. Together, these results suggest that USP36 acts as a SUMO ligase to promote EXOSC10 SUMOylation critical for the RNA exosome function in ribosome biogenesis.


Assuntos
Exorribonucleases , Complexo Multienzimático de Ribonucleases do Exossomo , Nucléolo Celular/genética , Nucléolo Celular/metabolismo , Exorribonucleases/genética , Exorribonucleases/metabolismo , Complexo Multienzimático de Ribonucleases do Exossomo/genética , Complexo Multienzimático de Ribonucleases do Exossomo/metabolismo , RNA/metabolismo , Precursores de RNA/genética , Precursores de RNA/metabolismo , Processamento Pós-Transcricional do RNA , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Humanos , Linhagem Celular
2.
Epilepsia ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38845412

RESUMO

SCN8A variants cause a spectrum of epilepsy phenotypes ranging from self-limited infantile epilepsy (SeLIE) to developmental and epileptic encephalopathy. SeLIE is an infantile onset focal epilepsy, occurring in developmentally normal infants, which often resolves by 3 years. Our aim was to ascertain when epilepsy resolves in SCN8A-SeLIE. We identified unpublished individuals with SCN8A-SeLIE and performed detailed phenotyping. Literature was searched for published SCN8A-SeLIE cases. Nine unpublished individuals from four families were identified (age at study = 3.5-66 years). Six had their last seizure after 3 years (range = 4-21 years); although drug-responsive and despite multiple weaning attempts (1-5), five of six remain on antiseizure medications (carbamazepine, n = 3; lamotrigine, n = 2). We identified 29 published individuals with SCN8A-SeLIE who had data on seizure progression. Of the 22 individuals aged at least 10 years, reported here or in the literature, nine of 22 (41%) had seizure offset prior to 3 years, five of 22 (23%) had seizure offset between 3 and 10 years, and eight of 22 (36%) had seizures after 10 years. Our data highlight that more than half of individuals with SCN8A-SeLIE continue to have seizures into late childhood. In contrast to SeLIE due to other etiologies, many individuals have a more persistent, albeit drug-responsive, form of epilepsy.

3.
Int J Behav Nutr Phys Act ; 20(1): 80, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37408045

RESUMO

BACKGROUND: Few whole-school physical activity programmes integrate implementation science frameworks within the design, delivery, and evaluation. As a result, knowledge of the key factors that support implementation at scale is lacking. The Creating Active Schools (CAS) programme was co-designed and is underpinned by the Capability, Opportunity, Motivation and Behaviour (COM-B) model and the Consolidated Framework for Implementation Research (CFIR). The study aims to understand the initial impact and implementation of CAS in Bradford over 9 months using McKay's et al.'s (2019) implementation evaluation roadmap. METHODS: Focus groups and interviews were conducted with school staff (n = 30, schools = 25), CAS Champions (n = 9), and the CAS strategic lead (n = 1). Qualitative data were analysed both inductively and deductively. The deductive analysis involved coding data into a priori themes based on McKay et al's implementation evaluation roadmap, using a codebook approach to thematic analysis. The inductive analysis included producing initial codes and reviewing themes before finalising. RESULTS: Identified themes aligned into three categories: (i) key ingredients for successful adoption and implementation of CAS, (ii) CAS implementation: challenges and solutions, and (iv) the perceived effectiveness of CAS at the school level. This included the willingness of schools to adopt and implement whole-school approaches when they are perceived as high quality and aligned with current school values. The programme implementation processes were seen as supportive; schools identified and valued the step-change approach to implementing CAS long-term. Formal and informal communities of practice provided "safe spaces" for cross-school support. Conversely, challenges persisted with gaining broader reach within schools, school staff's self-competence and shifting school culture around physical activity. This resulted in varied uptake between and within schools. CONCLUSIONS: This study provides novel insights into the implementation of CAS, with outcomes aligning to the adoption, reach, and sustainability. Successful implementation of CAS was underpinned by determinants including acceptability, intervention complexity, school culture and school stakeholders' perceived self-efficacy. The combination of McKay's evaluation roadmap and CFIR establishes a rigorous approach for evaluating activity promotion programmes underpinned by behavioural and implementation science. Resultantly this study offers originality and progression in understanding the implementation and effectiveness of whole-school approaches to physical activity.


Assuntos
Serviços de Saúde Escolar , Instituições Acadêmicas , Humanos , Exercício Físico , Grupos Focais , Reino Unido
4.
Curr Microbiol ; 80(6): 200, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37129770

RESUMO

Cellulomonas flavigena KU (ATCC 53703) produces an extracellular matrix involved in the degradation of microcrystalline cellulose. This extracellular material is primarily composed of the gel-forming, ß-1,3-glucan known as curdlan and associated, cellulose-degrading enzymes. In this study, the effects of various forms of nutrient limitation on cellulose attachment, cellular aggregation, curdlan production, and biofilm formation were investigated throughout a 7-day incubation period by using phase-contrast microscopy. Compared to cultures grown in non-limiting media, nitrogen-limitation promoted early attachment of C. flavigena KU cells to the cellulose surface, and cellulose attachment was congruent with cellular aggregation and curdlan production. Over the course of the experiment, microcolonies of attached cells grew into curdlan-producing biofilms on the cellulose. By contrast, bacterial cells grown on cellulose in non-limiting media remained unattached and unaggregated throughout most of the incubation period. By 7 days of incubation, bacterial aggregation was ninefold greater in N-limited cultures compared to nutritionally complete cultures. In a similar way, phosphorus- and vitamin-limitation (i.e., yeast extract-limitation) also resulted in early cellulose attachment and biofilm formation. Furthermore, nutrient limitation promoted more rapid and efficient fragmentation and degradation of cellulose, with cellulose fragments in low-N media averaging half the size of those in high-N media after 7 days. Two modes of cellulose degradation are proposed for C. flavigena KU, a "planktonic mode" and a "biofilm mode". Similar observations have been reported for other curdlan-producing cellulomonads, and these differing cellulose degradation strategies may ultimately prove to reflect sequential stages of a multifaceted biofilm cycle important in the bioconversion of this abundant and renewable natural resource.


Assuntos
Celulose , Glucanos , Celulose/metabolismo , Biofilmes
5.
Differentiation ; 123: 30-41, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34906895

RESUMO

Adolescent Idiopathic Scoliosis (AIS) is the most common type of spine deformity affecting 2-3% of the population worldwide. The etiology of this disease is still poorly understood. Several GWAS studies have identified single nucleotide polymorphisms (SNPs) located near the gene LBX1 that is significantly correlated with AIS risk. LBX1 is a transcription factor with roles in myocyte precursor migration, cardiac neural crest specification, and neuronal fate determination in the neural tube. Here, we further investigated the role of LBX1 in the developing spinal cord of mouse embryos using a CRISPR-generated mouse model expressing a truncated version of LBX1 (Lbx1Δ). Homozygous mice died at birth, likely due to cardiac abnormalities. To further study the neural tube phenotype, we used RNA-sequencing to identify 410 genes differentially expressed between the neural tubes of E12.5 wildtype and Lbx1Δ/Δ embryos. Genes with increased expression in the deletion line were involved in neurogenesis and those with broad roles in embryonic development. Many of these genes have also been associated with scoliotic phenotypes. In comparison, genes with decreased expression were primarily involved in skeletal development. Subsequent skeletal and immunohistochemistry analysis further confirmed these results. This study aids in understanding the significance of links between LBX1 function and AIS susceptibility.


Assuntos
Proteínas de Homeodomínio , Escoliose , Animais , Proteínas de Homeodomínio/genética , Camundongos , Fenótipo , Polimorfismo de Nucleotídeo Único , Escoliose/genética , Fatores de Transcrição/genética
6.
BMC Psychiatry ; 22(1): 669, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307752

RESUMO

BACKGROUND: The experience sampling method (ESM) is an intensive longitudinal research method.  Participants complete questionnaires at multiple times about their current or very recent state. The design of ESM studies is complex. People with psychosis have been shown to be less adherent to ESM study protocols than the general population. It is not known how to design studies that increase adherence to study protocols. A lack of typology makes it is hard for researchers to decide how to collect data in a way that allows for methodological rigour, quality of reporting, and the ability to synthesise findings. The aims of this systematic review were to characterise the design choices made in ESM studies monitoring the daily lives of people with psychosis, and to synthesise evidence relating the data completeness to different design choices. METHODS: A systematic review was conducted of published literature on studies using ESM with people with psychosis. Studies were included if they used digital technology for data collection and reported the completeness of the data set. The constant comparative method was used to identify design decisions, using inductive identification of design decisions with simultaneous comparison of design decisions observed. Weighted regression was used to identify design decisions that predicted data completeness. The review was pre-registered (PROSPERO CRD42019125545). RESULTS: Thirty-eight studies were included. A typology of design choices used in ESM studies was developed, which comprised three superordinate categories of design choice: Study context, ESM approach and ESM implementation. Design decisions that predict data completeness include type of ESM protocol used, length of time participants are enrolled in the study, and if there is contact with the research team during data collection. CONCLUSIONS: This review identified a range of design decisions used in studies using ESM in the context of psychosis. Design decisions that influence data completeness were identified. Findings will help the design and reporting of future ESM studies. Results are presented with the focus on psychosis, but the findings can be applied across different mental health populations.


Assuntos
Avaliação Momentânea Ecológica , Transtornos Psicóticos , Humanos , Transtornos Psicóticos/diagnóstico , Projetos de Pesquisa , Inquéritos e Questionários
7.
J Med Internet Res ; 23(1): e22619, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33326409

RESUMO

BACKGROUND: In response to COVID-19, there has been increasing momentum in telehealth development and delivery. To assess the anticipated exponential growth in telehealth, it is important to accurately capture how telehealth has been used in specific mental health fields prior to the pandemic. OBJECTIVE: This systematic review aimed to highlight how telehealth has been used with clinical samples in the neurodevelopmental field, including patients with neurodevelopmental disorders (NDDs), their families, and health care professionals. To identify which technologies show the greatest potential for implementation into health services, we evaluated technologies for effectiveness, economic impact, and readiness for clinical adoption. METHODS: A systematic search of literature was undertaken in April 2018 and updated until December 2019, by using the Medline, Web of Science, Scopus, CINAHL Plus, EMBASE, and PsycInfo databases. Extracted data included the type of technology, how the technology was used (ie, assessment, treatment, and monitoring), participant characteristics, reported outcomes and authors' views on clinical effectiveness, user impact (ie, feasibility and acceptability), economic impact, and readiness for clinic adoption. A quality review of the research was performed in accordance with the Oxford Centre for Evidence-Based Medicine Levels of Evidence. RESULTS: A total of 42 studies met the inclusion criteria. These studies included participants and family members with autism spectrum disorders (21/42, 50%), attention deficit hyperactivity disorders (8/42, 19%), attention deficit hyperactivity or autism spectrum disorders (3/42, 7%), communication disorders (7/42, 17%), and tic disorders (2/42, 5%). The focus of most studies (33/42, 79%) was on treatment, rather than assessment (4/42, 10%) or monitoring (5/42, 12%). Telehealth services demonstrated promise for being clinically effective, predominantly in relation to diagnosing and monitoring NDDs. In terms of NDD treatment, telehealth services were usually equivalent to control groups. There was some evidence of positive user and economic impacts, including increased service delivery efficiency (eg, increased treatment availability and decreased waiting times). However, these factors were not widely recorded across the studies. Telehealth was demonstrated to be cost-effective in the few studies that considered cost-effectiveness. Study quality varied, as many studies had small sample sizes and inadequate control groups. Of the 42 studies, only 11 (26%) were randomized controlled trials, 12 (29%) were case studies or case series, 6 (14%) were qualitative studies, and 5 (12%) were noncomparative trials. CONCLUSIONS: Telehealth has the potential to increase treatment availability, decrease diagnosis waiting times, and aid in NDD monitoring. Further research with more robust and adequately powered study designs that consider cost-effectiveness and increased efficiency is needed. This systematic review highlights the extent of telehealth technology use prior to the COVID-19 pandemic and the movement for investing in remote access to treatments. TRIAL REGISTRATION: PROSPERO International Prospective Register of Systematic Reviews CRD42018091156; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42018091156.


Assuntos
Monitorização Fisiológica/métodos , Transtornos do Neurodesenvolvimento/terapia , Telemedicina/métodos , Feminino , Humanos , Masculino , Transtornos do Neurodesenvolvimento/epidemiologia , Pesquisa Qualitativa
8.
Emerg Med J ; 38(8): 587-593, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34083427

RESUMO

BACKGROUND: The WHO and National Institute for Health and Care Excellence recommend various triage tools to assist decision-making for patients with suspected COVID-19. We aimed to compare the accuracy of triage tools for predicting severe illness in adults presenting to the ED with suspected COVID-19. METHODS: We undertook a mixed prospective and retrospective observational cohort study in 70 EDs across the UK. We collected data from people attending with suspected COVID-19 and used presenting data to determine the results of assessment with the WHO algorithm, National Early Warning Score version 2 (NEWS2), CURB-65, CRB-65, Pandemic Modified Early Warning Score (PMEWS) and the swine flu adult hospital pathway (SFAHP). We used 30-day outcome data (death or receipt of respiratory, cardiovascular or renal support) to determine prognostic accuracy for adverse outcome. RESULTS: We analysed data from 20 891 adults, of whom 4611 (22.1%) died or received organ support (primary outcome), with 2058 (9.9%) receiving organ support and 2553 (12.2%) dying without organ support (secondary outcomes). C-statistics for the primary outcome were: CURB-65 0.75; CRB-65 0.70; PMEWS 0.77; NEWS2 (score) 0.77; NEWS2 (rule) 0.69; SFAHP (6-point rule) 0.70; SFAHP (7-point rule) 0.68; WHO algorithm 0.61. All triage tools showed worse prediction for receipt of organ support and better prediction for death without organ support. At the recommended threshold, PMEWS and the WHO criteria showed good sensitivity (0.97 and 0.95, respectively) at the expense of specificity (0.30 and 0.27, respectively). The NEWS2 score showed similar sensitivity (0.96) and specificity (0.28) when a lower threshold than recommended was used. CONCLUSION: CURB-65, PMEWS and the NEWS2 score provide good but not excellent prediction for adverse outcome in suspected COVID-19, and predicted death without organ support better than receipt of organ support. PMEWS, the WHO criteria and NEWS2 (using a lower threshold than usually recommended) provide good sensitivity at the expense of specificity. TRIAL REGISTRATION NUMBER: ISRCTN56149622.


Assuntos
COVID-19/terapia , Serviço Hospitalar de Emergência , Pneumonia Viral/terapia , Triagem/métodos , Idoso , COVID-19/epidemiologia , Escore de Alerta Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , SARS-CoV-2 , Reino Unido
9.
Emerg Med J ; 38(2): 88-93, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33273040

RESUMO

BACKGROUND: Measurement of post-exertion oxygen saturation has been proposed to assess illness severity in suspected COVID-19 infection. We aimed to determine the accuracy of post-exertional oxygen saturation for predicting adverse outcome in suspected COVID-19. METHODS: We undertook a substudy of an observational cohort study across 70 emergency departments during the first wave of the COVID-19 pandemic in the UK. We collected data prospectively, using a standardised assessment form, and retrospectively, using hospital records, from patients with suspected COVID-19, and reviewed hospital records at 30 days for adverse outcome (death or receiving organ support). Patients with post-exertion oxygen saturation recorded were selected for this analysis. We constructed receiver-operating characteristic curves, calculated diagnostic parameters, and developed a multivariable model for predicting adverse outcome. RESULTS: We analysed data from 817 patients with post-exertion oxygen saturation recorded after excluding 54 in whom measurement appeared unfeasible. The c-statistic for post-exertion change in oxygen saturation was 0.589 (95% CI 0.465 to 0.713), and the positive and negative likelihood ratios of a 3% or more desaturation were, respectively, 1.78 (1.25 to 2.53) and 0.67 (0.46 to 0.98). Multivariable analysis showed that post-exertion oxygen saturation was not a significant predictor of adverse outcome when baseline clinical assessment was taken into account (p=0.368). Secondary analysis excluding patients in whom post-exertion measurement appeared inappropriate resulted in a c-statistic of 0.699 (0.581 to 0.817), likelihood ratios of 1.98 (1.26 to 3.10) and 0.61 (0.35 to 1.07), and some evidence of additional prognostic value on multivariable analysis (p=0.019). CONCLUSIONS: Post-exertion oxygen saturation provides modest prognostic information in the assessment of selected patients attending the emergency department with suspected COVID-19. TRIAL REGISTRATION NUMBER: ISRCTN Registry (ISRCTN56149622) http://www.isrctn.com/ISRCTN28342533.


Assuntos
COVID-19/diagnóstico , Oxigênio/análise , Esforço Físico , Adulto , Idoso , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
10.
Parasitol Res ; 119(5): 1563-1572, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32246260

RESUMO

In temperate regions, some avian haemosporidian parasites have evolved seasonal transmission strategies, with chronic infections relapsing during spring and transmission peaking during the hosts' breeding season. Because lineages with seasonal transmission strategies are unlikely to produce gametocytes in winter, we predicted that (1) resident birds living within wintering areas of Neotropical migrants would unlikely be infected with North American parasite lineages; and (2) if infected, wintering migratory birds would be more likely to harbor Plasmodium spp. rather than Parahaemoproteus spp. or Haemoproteus spp. parasites in their bloodstreams, as only Plasmodium produces life stages, other than gametocytes, that infect red blood cells. To test these predictions, we used molecular detection and microscopy to compare the diversity and prevalence of haemosporidian parasites among year-round residents and wintering migratory birds during February 2016, on three islands of The Bahamas archipelago, i.e., Andros, Grand Bahama, and Great Abaco. Infection prevalence was low and comparable between migratory (15/111) and resident (15/129) individuals, and it did not differ significantly among islands. Out of the 12 lineages detected infecting migratory birds, five were transmitted in North America; four lineages could have been transmitted during breeding, wintering, or migration; and three lineages were likely transmitted in The Bahamas. Resident birds mostly carried lineages endemic to the Caribbean region. All North American-transmitted parasite lineages detected among migratory birds were Plasmodium spp. Our findings suggest that haemosporidian parasites of migrants shift resource allocation seasonally, minimizing the production of gametocytes during winter, with low risk of infection spillover to resident birds.


Assuntos
Doenças das Aves/parasitologia , Aves/parasitologia , Haemosporida/isolamento & purificação , Plasmodium/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Migração Animal/fisiologia , Animais , Bahamas/epidemiologia , Doenças das Aves/epidemiologia , Haemosporida/classificação , Haemosporida/genética , Plasmodium/genética , Prevalência , Infecções Protozoárias em Animais/parasitologia , Estações do Ano
11.
J Med Internet Res ; 22(7): e16228, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32628116

RESUMO

BACKGROUND: The prevalence of mental health disorders continues to rise, with almost 4% of the world population having an anxiety disorder and almost 3.5% having depression in 2017. Despite the high prevalence, only one-third of people with depression or anxiety receive treatment. Over the last decade, the use of digital health interventions (DHIs) has risen rapidly as a means of accessing mental health care and continues to increase. Although there is evidence supporting the effectiveness of DHIs for the treatment of mental health conditions, little is known about what aspects are valued by users and how they might be improved. OBJECTIVE: This systematic review aimed to identify, appraise, and synthesize the qualitative literature available on service users' views and experiences regarding the acceptability and usability of DHIs for depression, anxiety, and somatoform disorders. METHODS: A systematic search strategy was developed, and searches were run in 7 electronic databases. Qualitative and mixed methods studies published in English were included. A meta-synthesis was used to interpret and synthesize the findings from the included studies. RESULTS: A total of 24 studies were included in the meta-synthesis, and 3 key themes emerged with descriptive subthemes. The 3 key themes were initial motivations and approaches to DHIs, personalization of treatment, and the value of receiving personal support in DHIs. The meta-synthesis suggests that participants' initial beliefs about DHIs can have an important effect on their engagement with these types of interventions. Personal support was valued very highly as a major component of the success of DHIs. The main reason for this was the way it enabled individual personalization of care. CONCLUSIONS: Findings from the systematic review have implications for the design of future DHIs to improve uptake, retention, and outcomes in DHIs for depression, anxiety, and somatoform disorders. DHIs need to be personalized to the specific needs of the individual. Future research should explore whether the findings could be generalized to other health conditions.


Assuntos
Depressão/terapia , Transtornos Somatoformes/terapia , Telemedicina/métodos , Adulto , Transtornos de Ansiedade/terapia , Humanos
12.
Haematologica ; 104(2): 360-369, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30262567

RESUMO

Chronic lymphocytic leukemia (CLL) patients with differential somatic hypermutation status of the immunoglobulin heavy variable genes, namely mutated or unmutated, display fundamental clinico-biological differences. Considering this, we assessed prognosis separately within mutated (M-CLL) and unmutated (U-CLL) CLL in 3015 patients, hypothesizing that the relative significance of relevant indicators may differ between these two categories. Within Binet A M-CLL patients, besides TP53 abnormalities, trisomy 12 and stereotyped subset #2 membership were equivalently associated with the shortest time-to-first-treatment and a treatment probability at five and ten years after diagnosis of 40% and 55%, respectively; the remaining cases exhibited 5-year and 10-year treatment probability of 12% and 25%, respectively. Within Binet A U-CLL patients, besides TP53 abnormalities, del(11q) and/or SF3B1 mutations were associated with the shortest time-to-first-treatment (5- and 10-year treatment probability: 78% and 98%, respectively); in the remaining cases, males had a significantly worse prognosis than females. In conclusion, the relative weight of indicators that can accurately risk stratify early-stage CLL patients differs depending on the somatic hypermutation status of the immunoglobulin heavy variable genes of each patient. This finding highlights the fact that compartmentalized approaches based on immunogenetic features are necessary to refine and tailor prognostication in CLL.


Assuntos
Biomarcadores Tumorais , Suscetibilidade a Doenças , Leucemia Linfocítica Crônica de Células B/etiologia , Leucemia Linfocítica Crônica de Células B/mortalidade , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Feminino , Humanos , Imunogenética , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/patologia , Leucemia Linfocítica Crônica de Células B/terapia , Masculino , Mutação , Estadiamento de Neoplasias , Prognóstico , Tempo para o Tratamento
13.
Blood ; 127(8): 1007-16, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26675346

RESUMO

Fludarabine, cyclophosphamide, and rituximab (FCR) is first-line treatment of medically fit chronic lymphocytic leukemia (CLL) patients; however, despite good response rates, many patients eventually relapse. Although recent high-throughput studies have identified novel recurrent genetic lesions in adverse prognostic CLL, the mechanisms leading to relapse after FCR therapy are not completely understood. To gain insight into this issue, we performed whole-exome sequencing of sequential samples from 41 CLL patients who were uniformly treated with FCR but relapsed after a median of 2 years. In addition to mutations with known adverse-prognostic impact (TP53, NOTCH1, ATM, SF3B1, NFKBIE, and BIRC3), a large proportion of cases (19.5%) harbored mutations in RPS15, a gene encoding a component of the 40S ribosomal subunit. Extended screening, totaling 1119 patients, supported a role for RPS15 mutations in aggressive CLL, with one-third of RPS15-mutant cases also carrying TP53 aberrations. In most cases, selection of dominant, relapse-specific subclones was observed over time. However, RPS15 mutations were clonal before treatment and remained stable at relapse. Notably, all RPS15 mutations represented somatic missense variants and resided within a 7 amino-acid, evolutionarily conserved region. We confirmed the recently postulated direct interaction between RPS15 and MDM2/MDMX and transient expression of mutant RPS15 revealed defective regulation of endogenous p53 compared with wild-type RPS15. In summary, we provide novel insights into the heterogeneous genetic landscape of CLL relapsing after FCR treatment and highlight a novel mechanism underlying clinical aggressiveness involving a mutated ribosomal protein, potentially representing an early genetic lesion in CLL pathobiology.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Linfocítica Crônica de Células B/genética , Mutação de Sentido Incorreto , Recidiva Local de Neoplasia/genética , Proteínas Ribossômicas/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Western Blotting , Separação Celular , Ciclofosfamida/administração & dosagem , Análise Mutacional de DNA , Exoma , Humanos , Imunoprecipitação , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/patologia , Recidiva Local de Neoplasia/patologia , Rituximab/administração & dosagem , Transfecção , Proteína Supressora de Tumor p53/genética , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados
14.
Blood ; 128(23): 2666-2670, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27670424

RESUMO

We recently reported a truncating deletion in the NFKBIE gene, which encodes IκBε, a negative feedback regulator of NF-κB, in clinically aggressive chronic lymphocytic leukemia (CLL). Because preliminary data indicate enrichment of NFKBIE aberrations in other lymphoid malignancies, we screened a large patient cohort (n = 1460) diagnosed with different lymphoid neoplasms. While NFKBIE deletions were infrequent in follicular lymphoma, splenic marginal zone lymphoma, and T-cell acute lymphoblastic leukemia (<2%), slightly higher frequencies were seen in diffuse large B-cell lymphoma, mantle cell lymphoma, and primary central nervous system lymphoma (3% to 4%). In contrast, a remarkably high frequency of NFKBIE aberrations (46/203 cases [22.7%]) was observed in primary mediastinal B-cell lymphoma (PMBL) and Hodgkin lymphoma (3/11 cases [27.3%]). NFKBIE-deleted PMBL patients were more often therapy refractory (P = .022) and displayed inferior outcome compared with wild-type patients (5-year survival, 59% vs 78%; P = .034); however, they appeared to benefit from radiotherapy (P =022) and rituximab-containing regimens (P = .074). NFKBIE aberrations remained an independent factor in multivariate analysis (P = .003) and when restricting the analysis to immunochemotherapy-treated patients (P = .008). Whole-exome sequencing and gene expression profiling verified the importance of NF-κB deregulation in PMBL. In summary, we identify NFKBIE aberrations as a common genetic event across B-cell malignancies and highlight NFKBIE deletions as a novel poor-prognostic marker in PMBL.


Assuntos
Biomarcadores Tumorais/genética , Deleção de Genes , Proteínas I-kappa B/genética , Linfoma de Células B , Neoplasias do Mediastino , Proteínas Proto-Oncogênicas/genética , Adolescente , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Linfoma de Células B/genética , Linfoma de Células B/mortalidade , Masculino , Neoplasias do Mediastino/genética , Neoplasias do Mediastino/mortalidade , Pessoa de Meia-Idade , Taxa de Sobrevida
15.
Retina ; 38(9): 1816-1823, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28723846

RESUMO

PURPOSE: To use fractal dimensional analysis to investigate retinal vascular disease patterns in patients with diabetic retinopathy using spectral domain optical coherence tomography angiography. METHODS: A retrospective study was conducted which included 49 eyes from 26 control subjects and 58 eyes from 35 patients known to have diabetic retinopathy. Of the 58 eyes with known retinopathy, 31 were categorized as nonproliferative diabetic retinopathy (13 mild, 9 moderate, and 9 severe) and 27 were categorized as proliferative diabetic retinopathy. Optical coherence tomography angiography images were acquired using the RTVue XR Avanti (Optovue, Inc). Automated segmentation was obtained through both the superficial and deep capillary plexuses for each eye. Grayscale optical coherence tomography angiography images were standardized and binarized using ImageJ (National Institutes of Health). Fractal box-counting analyses were conducted using Fractalyse (ThéMA). Fractal dimensions (FDs) and correlation coefficient of the superficial and deep capillary plexuses were compared between control eyes and those in various stages of diabetic retinopathy. RESULTS: The superficial and deep capillary plexuses from diabetic and control eyes were analyzed. The average FD for diabetic eyes was significantly lower than in control eyes in the superficial plexus (P = 2.4 × 10) and in the deep capillary plexus (P = 1.87 × 10 ) with a more statistically significant difference noted in the deep capillary plexus. When analyzing diabetic patients without edema noted on optical coherence tomography, the FD was significantly reduced in the superficial (P = 0.001) and deep (P = 1.49 × 10) plexuses. When analyzing diabetic patients with edema noted on optical coherence tomography, the FD was significantly reduced in the superficial (P = 2.0 × 10) and deep (P = 1.85 × 10) plexuses. CONCLUSION: The optical coherence tomography angiography FD is significantly lower in both superficial and deep capillary plexuses in eyes with all stages studied of diabetic retinopathy. The results were more often significant for the deep capillary plexus. The use of fractal analysis provides an objective criterion to assess microvascular disease burden in diabetic retinopathy.


Assuntos
Retinopatia Diabética/diagnóstico , Angiofluoresceinografia/métodos , Fractais , Retina/patologia , Acuidade Visual , Adulto , Idoso , Idoso de 80 Anos ou mais , Retinopatia Diabética/fisiopatologia , Progressão da Doença , Feminino , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Tomografia de Coerência Óptica/métodos , Adulto Jovem
16.
Haematologica ; 102(3): 562-572, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27927767

RESUMO

Chronic lymphocytic leukemia is characterized by impaired immune functions largely due to profound T-cell defects. T-cell functions also depend on co-signaling receptors, inhibitory or stimulatory, known as immune checkpoints, including cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and programmed death-1 (PD-1). Here we analyzed the T-cell phenotype focusing on immune checkpoints and activation markers in chronic lymphocytic leukemia patients (n=80) with different clinical characteristics and compared them to healthy controls. In general, patients had higher absolute numbers of CD3+ cells and the CD8+ subset was particularly expanded in previously treated patients. Progressive patients had higher numbers of CD4+ and CD8+ cells expressing PD-1 compared to healthy controls, which was more pronounced in previously treated patients (P=0.0003 and P=0.001, respectively). A significant increase in antigen-experienced T cells was observed in patients within both the CD4+ and CD8+ subsets, with a significantly higher PD-1 expression. Higher numbers of CD4+ and CD8+ cells with intracellular CTLA-4 were observed in patients, as well as high numbers of proliferating (Ki67+) and activated (CD69+) CD4+ and CD8+ cells, more pronounced in patients with active disease. The numbers of Th1, Th2, Th17 and regulatory T cells were substantially increased in patients compared to controls (P<0.05), albeit decreasing to low levels in pre-treated patients. In conclusion, chronic lymphocytic leukemia T cells display increased expression of immune checkpoints, abnormal subset distribution, and a higher proportion of proliferating cells compared to healthy T cells. Disease activity and previous treatment shape the T-cell profile of chronic lymphocytic leukemia patients in different ways.


Assuntos
Biomarcadores Tumorais , Regulação Leucêmica da Expressão Gênica , Imunomodulação/genética , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Idoso , Biomarcadores , Antígeno CTLA-4/genética , Antígeno CTLA-4/metabolismo , Estudos de Casos e Controles , Aberrações Cromossômicas , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Imunofenotipagem , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/terapia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Mutação , Fenótipo , Prognóstico , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
17.
Anal Chem ; 88(3): 1496-505, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26703823

RESUMO

Nuclear forensic science, or "nuclear forensic", aims to answer questions about nuclear material found outside of regulatory control. In this Feature, we provide a general overview of nuclear forensics, selecting examples of key "nuclear forensic signatures" which have allowed investigators to determine the identity of unknown nuclear material in real investigations.


Assuntos
Ciências Forenses/métodos , Aplicação da Lei , Monitoramento de Radiação , Resíduos Radioativos/análise , Medidas de Segurança , Humanos
18.
Haematologica ; 101(8): 959-67, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27198719

RESUMO

We report on markedly different frequencies of genetic lesions within subsets of chronic lymphocytic leukemia patients carrying mutated or unmutated stereotyped B-cell receptor immunoglobulins in the largest cohort (n=565) studied for this purpose. By combining data on recurrent gene mutations (BIRC3, MYD88, NOTCH1, SF3B1 and TP53) and cytogenetic aberrations, we reveal a subset-biased acquisition of gene mutations. More specifically, the frequency of NOTCH1 mutations was found to be enriched in subsets expressing unmutated immunoglobulin genes, i.e. #1, #6, #8 and #59 (22-34%), often in association with trisomy 12, and was significantly different (P<0.001) to the frequency observed in subset #2 (4%, aggressive disease, variable somatic hypermutation status) and subset #4 (1%, indolent disease, mutated immunoglobulin genes). Interestingly, subsets harboring a high frequency of NOTCH1 mutations were found to carry few (if any) SF3B1 mutations. This starkly contrasts with subsets #2 and #3 where, despite their immunogenetic differences, SF3B1 mutations occurred in 45% and 46% of cases, respectively. In addition, mutations within TP53, whilst enriched in subset #1 (16%), were rare in subsets #2 and #8 (both 2%), despite all being clinically aggressive. All subsets were negative for MYD88 mutations, whereas BIRC3 mutations were infrequent. Collectively, this striking bias and skewed distribution of mutations and cytogenetic aberrations within specific chronic lymphocytic leukemia subsets implies that the mechanisms underlying clinical aggressiveness are not uniform, but rather support the existence of distinct genetic pathways of clonal evolution governed by a particular stereotyped B-cell receptor selecting a certain molecular lesion(s).


Assuntos
Biomarcadores Tumorais , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Mutação , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/metabolismo , Regiões Determinantes de Complementaridade/genética , Análise Citogenética , Feminino , Frequência do Gene , Rearranjo Gênico do Linfócito B , Genes de Imunoglobulinas , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região de Junção de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Polimorfismo de Nucleotídeo Único , Prognóstico
20.
Haematologica ; 100(3): 370-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25480502

RESUMO

Next-generation sequencing has revealed novel recurrent mutations in chronic lymphocytic leukemia, particularly in patients with aggressive disease. Here, we explored targeted re-sequencing as a novel strategy to assess the mutation status of genes with prognostic potential. To this end, we utilized HaloPlex targeted enrichment technology and designed a panel including nine genes: ATM, BIRC3, MYD88, NOTCH1, SF3B1 and TP53, which have been linked to the prognosis of chronic lymphocytic leukemia, and KLHL6, POT1 and XPO1, which are less characterized but were found to be recurrently mutated in various sequencing studies. A total of 188 chronic lymphocytic leukemia patients with poor prognostic features (unmutated IGHV, n=137; IGHV3-21 subset #2, n=51) were sequenced on the HiSeq 2000 and data were analyzed using well-established bioinformatics tools. Using a conservative cutoff of 10% for the mutant allele, we found that 114/180 (63%) patients carried at least one mutation, with mutations in ATM, BIRC3, NOTCH1, SF3B1 and TP53 accounting for 149/177 (84%) of all mutations. We selected 155 mutations for Sanger validation (variant allele frequency, 10-99%) and 93% (144/155) of mutations were confirmed; notably, all 11 discordant variants had a variant allele frequency between 11-27%, hence at the detection limit of conventional Sanger sequencing. Technical precision was assessed by repeating the entire HaloPlex procedure for 63 patients; concordance was found for 77/82 (94%) mutations. In summary, this study demonstrates that targeted next-generation sequencing is an accurate and reproducible technique potentially suitable for routine screening, eventually as a stand-alone test without the need for confirmation by Sanger sequencing.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Leucemia Linfocítica Crônica de Células B/diagnóstico , Mutação , Proteínas de Neoplasias/genética , Alelos , Expressão Gênica , Frequência do Gene , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Proteínas de Neoplasias/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Prognóstico , Fatores de Processamento de RNA , Receptor Notch1/genética , Receptor Notch1/metabolismo , Ribonucleoproteína Nuclear Pequena U2/genética , Ribonucleoproteína Nuclear Pequena U2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA