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1.
Blood ; 144(1): 84-98, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38579286

RESUMO

ABSTRACT: The overall prognosis of acute myeloid leukemia (AML) remains dismal, largely because of the inability of current therapies to kill leukemia stem cells (LSCs) with intrinsic resistance. Loss of the stress sensor growth arrest and DNA damage-inducible 45 alpha (GADD45A) is implicated in poor clinical outcomes, but its role in LSCs and AML pathogenesis is unknown. Here, we define GADD45A as a key downstream target of G protein-coupled receptor (LGR)4 pathway and discover a regulatory role for GADD45A loss in promoting leukemia-initiating activity and oxidative resistance in LGR4/HOXA9-dependent AML, a poor prognosis subset of leukemia. Knockout of GADD45A enhances AML progression in murine and patient-derived xenograft (PDX) mouse models. Deletion of GADD45A induces substantial mutations, increases LSC self-renewal and stemness in vivo, and reduces levels of reactive oxygen species (ROS), accompanied by a decreased response to ROS-associated genotoxic agents (eg, ferroptosis inducer RSL3) and acquisition of an increasingly aggressive phenotype on serial transplantation in mice. Our single-cell cellular indexing of transcriptomes and epitopes by sequencing analysis on patient-derived LSCs in PDX mice and subsequent functional studies in murine LSCs and primary AML patient cells show that loss of GADD45A is associated with resistance to ferroptosis (an iron-dependent oxidative cell death caused by ROS accumulation) through aberrant activation of antioxidant pathways related to iron and ROS detoxification, such as FTH1 and PRDX1, upregulation of which correlates with unfavorable outcomes in patients with AML. These results reveal a therapy resistance mechanism contributing to poor prognosis and support a role for GADD45A loss as a critical step for leukemia-initiating activity and as a target to overcome resistance in aggressive leukemia.


Assuntos
Proteínas de Ciclo Celular , Ferroptose , Leucemia Mieloide Aguda , Células-Tronco Neoplásicas , Animais , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/metabolismo , Camundongos , Humanos , Ferroptose/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Proteínas GADD45
2.
HIV Med ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39367662

RESUMO

BACKGROUND: In the context of an outbreak of HIV among people who inject drugs in Glasgow, Scotland, identified in 2015, our objectives were to: (1) develop epidemiological methods to estimate HIV incidence using data linkage, and (2) examine temporal changes in HIV incidence to inform public health responses. METHODS: This was a retrospective cohort study involving data linkage of laboratory HIV testing data to identify individuals with a history of drug use. Person-years (PY) and Poisson regression were used to estimate incidence by time period (pre-outbreak: 2000-2010 and 2011-2013; early outbreak: 2014-2016; ongoing outbreak: 2017-2019). RESULTS: Among 13 484 individuals tested for HIV, 144 incident HIV infections were observed from 2000 to 2019. Incidence rates increased from pre-outbreak periods (1.00/1000 PY (95% confidence interval, CI: 0.60-1.65) in 2000-2010 and 1.70/1000 PY (95% CI: 1.14-2.54) in 2011-2013) to 3.02/1000 PY (95% CI: 2.36-3.86) early outbreak (2014-2016) and 2.35 (95% CI 1.74-3.18) during the ongoing outbreak period (2017-2019). Compared with the pre-outbreak period (2000-2010), the incidence rates were significantly elevated during both the early outbreak (2014-16) (adjusted incidence rate ratio (aIRR) = 2.87, 95% CI: 1.62-5.09, p < 0.001) and the ongoing outbreak periods (2017-19) (aIRR = 2.12, 95% CI: 1.16-3.90, p = 0.015). CONCLUSIONS: Public health responses helped to curb the rising incidence of HIV infection among people with a history of drug use in Glasgow, but further efforts are needed to reduce it to levels observed prior to the outbreak. Data linkage of routine diagnostic test data to assess and monitor incidence of HIV infection provided enhanced surveillance, which is important to inform outbreak investigations and guide national strategies on elimination of HIV transmission.

3.
Transfusion ; 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39003752

RESUMO

BACKGROUND: Lookback investigations are conducted by blood services when a risk of transmission of infection from a donor to a recipient has been identified. They involve tracing transfusion recipients and offering them testing for the relevant infectious agent. Results are relayed to the recipient to provide reassurance that there has been no transmission or to ensure appropriate treatment and care if required, and blood services are able to learn lessons from the planning, delivery, and outcomes of the investigation. A national lookback exercise was conducted in Scotland following the introduction of a test to identify occult hepatitis B infection, as recommended by the UK Advisory Committee for the Safety of Blood, Tissues and Organs (SaBTO) in 2021. METHODS AND MATERIALS: This paper outlines the development and delivery of a national lookback program. It discusses the logistical, economic, ethical, regulatory, and scientific issues that were considered during the planning and delivery of the lookback exercise. RESULTS: Development and delivery of a national lookback required robust governance, engagement of all relevant stakeholders and a shared understanding of aims, effective communication, systems, resources, limitations, and project management. Outcomes included a high testing uptake, low levels of reported anxiety, and a comprehensive data set. CONCLUSION: Key aspects for delivery of a successful large-scale lookback program include a patient-centered approach, clear and accessible communication, and whole-systems multiagency collaboration. Major challenges include stakeholder engagement and capacity.

4.
AIDS Behav ; 28(6): 2131-2147, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38649554

RESUMO

Glasgow, Scotland's largest city, has been experiencing an HIV outbreak among people who inject drugs (PWID) since 2015. A key focus of the public health response has been to increase HIV testing among those at risk of infection. Our aim was to assess the impact of COVID-19 on HIV testing among PWID in Glasgow. HIV test uptake in the last 12 months was quantified among: (1) PWID recruited in six Needle Exchange Surveillance Initiative (NESI) surveys (n = 6110); linked laboratory data for (2) people prescribed opioid agonist therapy (OAT) (n = 14,527) and (3) people hospitalised for an injecting-related hospital admission (IRHA) (n = 12,621) across four time periods: pre-outbreak (2010-2014); early-outbreak (2015-2016); ongoing-outbreak (2017-2019); and COVID-19 (2020-June 21). From the pre to ongoing period, HIV testing increased: the highest among people recruited in NESI (from 28% to 56%) and on OAT (from 17% to 54%) while the lowest was among people with an IRHA (from 15% to 42%). From the ongoing to the COVID-19 period, HIV testing decreased markedly among people prescribed OAT, from 54% to 37% (aOR 0.50, 95% CI 0.48-0.53), but increased marginally among people with an IRHA from 42% to 47% (aOR 1.19, 95% CI 1.08-1.31). In conclusion, progress in increasing testing in response to the HIV outbreak has been eroded by COVID-19. Adoption of a linked data approach could be warranted in other settings to inform efforts to eliminate HIV transmission.


Assuntos
COVID-19 , Infecções por HIV , Teste de HIV , SARS-CoV-2 , Abuso de Substâncias por Via Intravenosa , Humanos , Abuso de Substâncias por Via Intravenosa/epidemiologia , COVID-19/epidemiologia , Masculino , Feminino , Adulto , Infecções por HIV/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/diagnóstico , Teste de HIV/estatística & dados numéricos , Escócia/epidemiologia , Pessoa de Meia-Idade , Pandemias , Surtos de Doenças , Adulto Jovem
5.
Int J Cancer ; 152(7): 1399-1413, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36346110

RESUMO

The mitochondrion is a gatekeeper of apoptotic processes, and mediates drug resistance to several chemotherapy agents used to treat cancer. Neuroblastoma is a common solid cancer in young children with poor clinical outcomes following conventional chemotherapy. We sought druggable mitochondrial protein targets in neuroblastoma cells. Among mitochondria-associated gene targets, we found that high expression of the mitochondrial adenine nucleotide translocase 2 (SLC25A5/ANT2), was a strong predictor of poor neuroblastoma patient prognosis and contributed to a more malignant phenotype in pre-clinical models. Inhibiting this transporter with PENAO reduced cell viability in a panel of neuroblastoma cell lines in a TP53-status-dependant manner. We identified the histone deacetylase inhibitor, suberanilohydroxamic acid (SAHA), as the most effective drug in clinical use against mutant TP53 neuroblastoma cells. SAHA and PENAO synergistically reduced cell viability, and induced apoptosis, in neuroblastoma cells independent of TP53-status. The SAHA and PENAO drug combination significantly delayed tumour progression in pre-clinical neuroblastoma mouse models, suggesting that these clinically advanced inhibitors may be effective in treating the disease.


Assuntos
Translocador 2 do Nucleotídeo Adenina , Antineoplásicos , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos , Neuroblastoma , Animais , Camundongos , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Inibidores de Histona Desacetilases/farmacologia , Histonas/metabolismo , Ácidos Hidroxâmicos/uso terapêutico , Mitocôndrias/metabolismo , Neuroblastoma/tratamento farmacológico , Vorinostat/farmacologia , Translocador 2 do Nucleotídeo Adenina/antagonistas & inibidores
6.
Blood ; 138(16): 1441-1455, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34075404

RESUMO

Changes in gene regulation and expression govern orderly transitions from hematopoietic stem cells to terminally differentiated blood cell types. These transitions are disrupted during leukemic transformation, but knowledge of the gene regulatory changes underpinning this process is elusive. We hypothesized that identifying core gene regulatory networks in healthy hematopoietic and leukemic cells could provide insights into network alterations that perturb cell state transitions. A heptad of transcription factors (LYL1, TAL1, LMO2, FLI1, ERG, GATA2, and RUNX1) bind key hematopoietic genes in human CD34+ hematopoietic stem and progenitor cells (HSPCs) and have prognostic significance in acute myeloid leukemia (AML). These factors also form a densely interconnected circuit by binding combinatorially at their own, and each other's, regulatory elements. However, their mutual regulation during normal hematopoiesis and in AML cells, and how perturbation of their expression levels influences cell fate decisions remains unclear. In this study, we integrated bulk and single-cell data and found that the fully connected heptad circuit identified in healthy HSPCs persists, with only minor alterations in AML, and that chromatin accessibility at key heptad regulatory elements was predictive of cell identity in both healthy progenitors and leukemic cells. The heptad factors GATA2, TAL1, and ERG formed an integrated subcircuit that regulates stem cell-to-erythroid transition in both healthy and leukemic cells. Components of this triad could be manipulated to facilitate erythroid transition providing a proof of concept that such regulatory circuits can be harnessed to promote specific cell-type transitions and overcome dysregulated hematopoiesis.


Assuntos
Fator de Transcrição GATA2/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Proteína 1 de Leucemia Linfocítica Aguda de Células T/genética , Células Eritroides/metabolismo , Células Eritroides/patologia , Redes Reguladoras de Genes , Hematopoese , Humanos , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Regulador Transcricional ERG/genética
7.
Bioorg Chem ; 136: 106462, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37060785

RESUMO

The MYCN oncogene and histone deacetylases (HDACs) are key driver genes in the childhood cancer, neuroblastoma. We recently described a novel pyridobenzimidazole analogue, SE486-11, which enhanced the therapeutic effectiveness of HDAC inhibitors by increasing MYCN ubiquitination through effects on the deubiquitinase, ubiquitin-specific protease 5 (USP5). Here we describe the synthesis of a novel series of pyrimido[1,2-a]benzimidazole derivatives, and an evaluation of their cytopathic effects against non-malignant and human neuroblastoma cell lines. Among the tested analogues, 4-(4-methoxyphenyl)benzo[4,5]imidazo[1,2-a]pyrimidine (3a) was the most active compound against neuroblastoma cells (IC50 ≤ 2 µM), with low cytotoxicity (IC50 ≥ 15 µM) to normal cells. We show compound 3a bound to USP5 protein (Kd = 0.47 µM) in vitro and synergistically enhanced the efficacy of HDAC inhibitors against neuroblastoma cells. Moreover, knockdown of USP5 and MYCN in treated neuroblastoma cells showed that both USP5 and MYCN expression was necessary for the cytopathic activity of compound 3a, thus providing a clinically relevant rationale for further development of this of pyrimido[1,2-a]benzimidazole.


Assuntos
Inibidores de Histona Desacetilases , Neuroblastoma , Criança , Humanos , Benzimidazóis , Linhagem Celular Tumoral , Inibidores de Histona Desacetilases/farmacologia , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Proteases Específicas de Ubiquitina
8.
BMC Public Health ; 23(1): 337, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36793018

RESUMO

BACKGROUND: Accelerating declines in tuberculosis (TB) incidence is paramount for achieving global goals set for 2030 by the Sustainable Development Goals and the End TB Strategy. The aim of this study was to identify key country-level social determinants of national TB incidence trends. METHODS: This longitudinal ecological study used country-level data extracted from online databases from the period 2005-2015. We used multivariable Poisson regression models allowing for distinct within- and between-country effects to estimate associations between national TB incidence rates and 13 social determinants of health. The analysis was stratified by country income status. RESULTS: The study sample included 48 low- and lower-middle-income countries (LLMICs) and 68 high- and upper-middle income countries (HUMICs), with a total of 528 and 748 observations between 2005-2015, respectively. National TB incidence rates declined in 108/116 countries between 2005-2015, with an average drop of 12.95% in LLMICs and 14.09% in HUMICs. Between LLMICs, higher Human Development Index (HDI), social protection spending, TB case detection, and TB treatment success were associated with lower TB incidence. Higher prevalence of HIV/AIDS was associated with higher TB incidence. Within LLMICs, increases in HDI over time were associated with lower TB incidence rates. Between HUMICs, higher HDI, health spending, and diabetes prevalence were associated with lower TB incidence, whereas higher prevalence of HIV/AIDS and alcohol-use were associated with higher TB incidence. Within HUMICs, increases in HIV/AIDS and diabetes prevalence over time were associated with higher TB incidence. CONCLUSIONS: In LLMICs, TB incidence rates remain highest in countries with low human development, social protection spending and TB programme performance, and high rates of HIV/AIDS. Strengthening human development is likely to accelerate declines in TB incidence. In HUMICs, TB incidence rates remain highest in countries with low human development, health spending and diabetes prevalence, and high rates of HIV/AIDS and alcohol use. Here, slowing rising rates of HIV/AIDS and diabetes is likely to accelerate declines in TB incidence.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Tuberculose , Humanos , Incidência , Determinantes Sociais da Saúde , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Fatores Sociais , Infecções por HIV/epidemiologia
9.
BMC Public Health ; 23(1): 2218, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37950177

RESUMO

BACKGROUND: The global mining industry is an important partner in advancing the 2030 Agenda for Sustainable Development. In 2018, Anglo American plc published their Sustainable Mining Plan, containing a goal for improving health and wellbeing aligned with the Sustainable Development Goal 3 (SDG3) targets. Having formed an independent multidisciplinary research consortium, we designed and implemented a mixed-methods approach to attain a deeper understanding of SDG3 priorities within the local context of communities hosting Anglo American mining operations located in Latin America. METHODS: In 2019, within the host communities of three mining operations in Chile, three in Brazil, and one in Peru, we conducted a qualitative study which included stakeholder workshops and key informant interviews. We also quantitatively appraised existing health data. Findings emerging from the qualitative and quantitative assessments were compared to identify health and wellbeing priority areas for action relevant to each community. RESULTS: Across the three countries, 120 people took part in workshops and 35 in interviews. In these workshops and interviews, non-communicable diseases (SDG3.4), harmful alcohol consumption (SDG3.5), and pollution, particularly air pollution (SDG3.9), were consistently identified as areas for priority action. There were similarities in the reporting of individual, interpersonal, community, societal, and structural factors underlying these priority areas across the different communities. The availability of quantitative data was generally good at the state level, becoming increasing sparse as we focused on smaller geographies. The priorities identified in the quantitative assessments generally aligned with those highlighted in the qualitative data. CONCLUSIONS: We highlight the importance of engaging with local populations to understand and address health needs. To address the priorities identified, intervention packages tailored to the specific needs of host communities, that tackle associated upstream societal level factors, are required. To facilitate this, appropriate monitoring systems and epidemiological investigations should be implemented to better understand the local context and quantify health issues. In the host communities, it is essential for the mining sector to be a key health partner in promoting integrated programmes that contribute to achieving the priority objectives and targets aligned with the SDG3 agenda.


Assuntos
Desenvolvimento Sustentável , Humanos , Peru/epidemiologia , Brasil/epidemiologia , Chile/epidemiologia , América Latina
10.
Proc Natl Acad Sci U S A ; 117(32): 19141-19150, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32703811

RESUMO

Current strategies to direct therapy-loaded nanoparticles to the brain rely on functionalizing nanoparticles with ligands which bind target proteins associated with the blood-brain barrier (BBB). However, such strategies have significant brain-specificity limitations, as target proteins are not exclusively expressed at the brain microvasculature. Therefore, novel strategies which exploit alternative characteristics of the BBB are required to overcome nonspecific nanoparticle targeting to the periphery, thereby increasing drug efficacy and reducing detrimental peripheral side effects. Here, we present a simple, yet counterintuitive, brain-targeting strategy which exploits the higher impermeability of the BBB to selectively label the brain endothelium. This is achieved by harnessing the lower endocytic rate of brain endothelial cells (a key feature of the high BBB impermeability) to promote selective retention of free, unconjugated protein-binding ligands on the surface of brain endothelial cells compared to peripheral endothelial cells. Nanoparticles capable of efficiently binding to the displayed ligands (i.e., labeled endothelium) are consequently targeted specifically to the brain microvasculature with minimal "off-target" accumulation in peripheral organs. This approach therefore revolutionizes brain-targeting strategies by implementing a two-step targeting method which exploits the physiology of the BBB to generate the required brain specificity for nanoparticle delivery, paving the way to overcome targeting limitations and achieve clinical translation of neurological therapies. In addition, this work demonstrates that protein targets for brain delivery may be identified based not on differential tissue expression, but on differential endocytic rates between the brain and periphery.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/instrumentação , Células Endoteliais/metabolismo , Nanopartículas/metabolismo , Animais , Transporte Biológico , Encéfalo/irrigação sanguínea , Endotélio/metabolismo , Humanos , Ratos , Ratos Sprague-Dawley
11.
Int J Mol Sci ; 24(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37958555

RESUMO

MYCN amplification occurs in approximately 20-30% of neuroblastoma patients and correlates with poor prognosis. The TH-MYCN transgenic mouse model mimics the development of human high-risk neuroblastoma and provides strong evidence for the oncogenic function of MYCN. In this study, we identified mitotic dysregulation as a hallmark of tumor initiation in the pre-cancerous ganglia from TH-MYCN mice that persists through tumor progression. Single-cell quantitative-PCR of coeliac ganglia from 10-day-old TH-MYCN mice revealed overexpression of mitotic genes in a subpopulation of premalignant neuroblasts at a level similar to single cells derived from established tumors. Prophylactic treatment using antimitotic agents barasertib and vincristine significantly delayed the onset of tumor formation, reduced pre-malignant neuroblast hyperplasia, and prolonged survival in TH-MYCN mice. Analysis of human neuroblastoma tumor cohorts showed a strong correlation between dysregulated mitosis and features of MYCN amplification, such as MYC(N) transcriptional activity, poor overall survival, and other clinical predictors of aggressive disease. To explore the therapeutic potential of targeting mitotic dysregulation, we showed that genetic and chemical inhibition of mitosis led to selective cell death in neuroblastoma cell lines with MYCN over-expression. Moreover, combination therapy with antimitotic compounds and BCL2 inhibitors exploited mitotic stress induced by antimitotics and was synergistically toxic to neuroblastoma cell lines. These results collectively suggest that mitotic dysregulation is a key component of tumorigenesis in early neuroblasts, which can be inhibited by the combination of antimitotic compounds and pro-apoptotic compounds in MYCN-driven neuroblastoma.


Assuntos
Antimitóticos , Neuroblastoma , Humanos , Camundongos , Animais , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Linhagem Celular Tumoral , Camundongos Transgênicos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Neuroblastoma/patologia , Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica
12.
BMC Public Health ; 22(1): 68, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35016650

RESUMO

BACKGROUND: The global mining industry has an opportunity to mobilize resources to advance progress against the Sustainable Development Goals (SDGs). In 2018, the Anglo-American Group outlined aspirations for mining host communities to meet the SDG3 health targets. To progress from aspiration to action we designed and implemented a mixed-methods approach to attain a deeper understanding of the health and wellbeing priorities within the local context of host communities of fifteen mines in South Africa. METHODS: To identify local needs and priorities relating to SDG3 targets in host communities, stakeholder workshops and key informant interviews were conducted between June and August 2019. A baseline assessment of health data, related to each of the SDG3 targets and indicators and to each host community location, was also conducted. Findings emerging from the qualitative and quantitative baseline assessments were compared to identify the extent to which health issues aligned and health and wellbeing priority areas for action. RESULTS: A total of 407 people participated in the workshops, and 85 key informants were interviewed. Quantitative data were available at sub-national level for seven of the nine SDG3 targets and eleven of the 21 indicators. Key priority areas for action identified through alignment of the qualitative and quantitative data were maternal mortality (SDG3.1), HIV (SDG3.3.1), tuberculosis (SDG3.3.2), substance abuse (SDG3.5), and road traffic accidents (SDG3.6) We found consistency in the individual, interpersonal, community, societal, and structural factors underlying these priority areas. At a structural level, poor access to quality healthcare was raised at every workshop as a key factor underlying the achievement of all SDG3 targets. Of the five priority areas identified, HIV, TB and substance abuse were found to overlap in the study communities in terms of risk, burden, and underlying factors. CONCLUSIONS: We demonstrate a mixed method approach for identifying local health needs and prioritised SDG3 targets in mining host communities. Consistency in reporting suggests the need for effective, efficient and feasible interventions to address five priority areas. Given the prominent economic role of the mining sector in South Africa, it can play a critical role in implementing programmatic activities that further progress towards achieving the SDG3 targets.


Assuntos
Infecções por HIV , Tuberculose , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Mineração , África do Sul/epidemiologia , Desenvolvimento Sustentável
13.
J Clin Microbiol ; 59(6)2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-33782112

RESUMO

LamPORE is a novel diagnostic platform for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA combining loop-mediated isothermal amplification with nanopore sequencing, which could potentially be used to analyze thousands of samples per day on a single instrument. We evaluated the performance of LamPORE against reverse transcriptase PCR (RT-PCR) using RNA extracted from spiked respiratory samples and stored nose and throat swabs collected at two UK hospitals. The limit of detection of LamPORE was 10 genome copies/µl of extracted RNA, which is above the limit achievable by RT-PCR, but was not associated with a significant reduction of sensitivity in clinical samples. Positive clinical specimens came mostly from patients with acute symptomatic infection, and among them, LamPORE had a diagnostic sensitivity of 99.1% (226/228; 95% confidence interval [CI], 96.9% to 99.9%). Among negative clinical specimens, including 153 with other respiratory pathogens detected, LamPORE had a diagnostic specificity of 99.6% (278/279; 98.0% to 100.0%). Overall, 1.4% (7/514; 0.5% to 2.9%) of samples produced an indeterminate result on first testing, and repeat LamPORE testing on the same RNA extract had a reproducibility of 96.8% (478/494; 94.8% to 98.1%). LamPORE has a similar performance as RT-PCR for the diagnosis of SARS-CoV-2 infection in symptomatic patients and offers a promising approach to high-throughput testing.


Assuntos
COVID-19 , Sequenciamento por Nanoporos , Humanos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , RNA Viral/genética , Reprodutibilidade dos Testes , SARS-CoV-2 , Sensibilidade e Especificidade
14.
Exp Appl Acarol ; 84(3): 593-606, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34125334

RESUMO

Assessing the risk of tick-borne disease in areas with high visitor numbers is important from a public health perspective. Evidence suggests that tick presence, density, infection prevalence and the density of infected ticks can vary between habitats within urban green space, suggesting that the risk of Lyme borreliosis transmission can also vary. This study assessed nymph density, Borrelia prevalence and the density of infected nymphs across a range of habitat types in nine parks in London which receive millions of visitors each year. Ixodes ricinus were found in only two of the nine locations sampled, and here they were found in all types of habitat surveyed. Established I. ricinus populations were identified in the two largest parks, both of which had resident free-roaming deer populations. Highest densities of nymphs (15.68 per 100 m2) and infected nymphs (1.22 per 100 m2) were associated with woodland and under canopy habitats in Richmond Park, but ticks infected with Borrelia were found across all habitat types surveyed. Nymphs infected with Borrelia (7.9%) were only reported from Richmond Park, where Borrelia burgdorferi sensu stricto and Borrelia afzelii were identified as the dominant genospecies. Areas with short grass appeared to be less suitable for ticks and maintaining short grass in high footfall areas could be a good strategy for reducing the risk of Lyme borreliosis transmission to humans in such settings. In areas where this would create conflict with existing practices which aim to improve and/or meet historic landscape, biodiversity and public access goals, promoting public health awareness of tick-borne disease risks could also be utilised.


Assuntos
Grupo Borrelia Burgdorferi , Borrelia burgdorferi , Cervos , Ixodes , Doença de Lyme , Animais , Londres/epidemiologia , Doença de Lyme/epidemiologia , Ninfa , Reino Unido
15.
Emerg Infect Dis ; 26(1): 90-96, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31661056

RESUMO

During February 2018-January 2019, we conducted large-scale surveillance for the presence and prevalence of tick-borne encephalitis virus (TBEV) and louping ill virus (LIV) in sentinel animals and ticks in the United Kingdom. Serum was collected from 1,309 deer culled across England and Scotland. Overall, 4% of samples were ELISA-positive for the TBEV serocomplex. A focus in the Thetford Forest area had the highest proportion (47.7%) of seropositive samples. Ticks collected from culled deer within seropositive regions were tested for viral RNA; 5 of 2,041 ticks tested positive by LIV/TBEV real-time reverse transcription PCR, all from within the Thetford Forest area. From 1 tick, we identified a full-length genomic sequence of TBEV. Thus, using deer as sentinels revealed a potential TBEV focus in the United Kingdom. This detection of TBEV genomic sequence in UK ticks has important public health implications, especially for undiagnosed encephalitis.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Ixodidae/virologia , Animais , Cervos/parasitologia , Vírus da Encefalite Transmitidos por Carrapatos/genética , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/transmissão , Ensaio de Imunoadsorção Enzimática , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Masculino , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espécies Sentinelas/virologia , Análise de Sequência de RNA , Reino Unido/epidemiologia
16.
Int J Cancer ; 147(7): 1928-1938, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32086952

RESUMO

Patients with neuroblastoma due to MYCN oncogene amplification and consequent N-Myc oncoprotein overexpression have very poor prognosis. The cyclin-dependent kinase 7 (CDK7)/super-enhancer inhibitor THZ1 suppresses MYCN gene transcription, reduces neuroblastoma cell proliferation, but does not cause significant cell death. The protein kinase phosphatase 1 nuclear targeting subunit (PNUTS) has recently been shown to interact with c-Myc protein and suppresses c-Myc protein degradation. Here we screened the U.S. Food and Drug Administration-Approved Oncology Drugs Set V from the National Cancer Institute, and identified tyrosine kinase inhibitors (TKIs), including ponatinib and lapatinib, as the Approved Oncology Drugs exerting the best synergistic anticancer effects with THZ1 in MYCN-amplified neuroblastoma cells. Combination therapy with THZ1 and ponatinib or lapatinib synergistically induced neuroblastoma cell apoptosis, while having little effects in normal nonmalignant cells. Differential gene expression analysis identified PNUTS as one of the genes most synergistically reduced by the combination therapy. Reverse transcription polymerase chain reaction and immunoblot analyses confirmed that THZ1 and the TKIs synergistically downregulated PNUTS mRNA and protein expression and reduced N-Myc protein but not N-Myc mRNA expression. In addition, PNUTS knockdown resulted in decreased N-Myc protein but not mRNA expression and decreased MYCN-amplified neuroblastoma cell proliferation and survival. As CDK7 inhibitors are currently under clinical evaluation in patients, our data suggest the addition of the TKI ponatinib or lapatinib in CDK7 inhibitor clinical trials in patients.


Assuntos
Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Fenilenodiaminas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quinases Ciclina-Dependentes/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Sinergismo Farmacológico , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Lapatinib/farmacologia , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Piridazinas/farmacologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Quinase Ativadora de Quinase Dependente de Ciclina
17.
Cochrane Database Syst Rev ; 3: CD003316, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32196635

RESUMO

BACKGROUND: Levels of physical activity and physical fitness are low after stroke. Interventions to increase physical fitness could reduce mortality and reduce disability through increased function. OBJECTIVES: The primary objectives of this updated review were to determine whether fitness training after stroke reduces death, death or dependence, and disability. The secondary objectives were to determine the effects of training on adverse events, risk factors, physical fitness, mobility, physical function, health status and quality of life, mood, and cognitive function. SEARCH METHODS: In July 2018 we searched the Cochrane Stroke Trials Register, CENTRAL, MEDLINE, Embase, CINAHL, SPORTDiscus, PsycINFO, and four additional databases. We also searched ongoing trials registers and conference proceedings, screened reference lists, and contacted experts in the field. SELECTION CRITERIA: Randomised trials comparing either cardiorespiratory training or resistance training, or both (mixed training), with usual care, no intervention, or a non-exercise intervention in stroke survivors. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, assessed quality and risk of bias, and extracted data. We analysed data using random-effects meta-analyses and assessed the quality of the evidence using the GRADE approach. Diverse outcome measures limited the intended analyses. MAIN RESULTS: We included 75 studies, involving 3017 mostly ambulatory participants, which comprised cardiorespiratory (32 studies, 1631 participants), resistance (20 studies, 779 participants), and mixed training interventions (23 studies, 1207 participants). Death was not influenced by any intervention; risk differences were all 0.00 (low-certainty evidence). There were few deaths overall (19/3017 at end of intervention and 19/1469 at end of follow-up). None of the studies assessed death or dependence as a composite outcome. Disability scores were improved at end of intervention by cardiorespiratory training (standardised mean difference (SMD) 0.52, 95% CI 0.19 to 0.84; 8 studies, 462 participants; P = 0.002; moderate-certainty evidence) and mixed training (SMD 0.23, 95% CI 0.03 to 0.42; 9 studies, 604 participants; P = 0.02; low-certainty evidence). There were too few data to assess the effects of resistance training on disability. Secondary outcomes showed multiple benefits for physical fitness (VO2 peak and strength), mobility (walking speed) and physical function (balance). These physical effects tended to be intervention-specific with the evidence mostly low or moderate certainty. Risk factor data were limited or showed no effects apart from cardiorespiratory fitness (VO2 peak), which increased after cardiorespiratory training (mean difference (MD) 3.40 mL/kg/min, 95% CI 2.98 to 3.83; 9 studies, 438 participants; moderate-certainty evidence). There was no evidence of any serious adverse events. Lack of data prevents conclusions about effects of training on mood, quality of life, and cognition. Lack of data also meant benefits at follow-up (i.e. after training had stopped) were unclear but some mobility benefits did persist. Risk of bias varied across studies but imbalanced amounts of exposure in control and intervention groups was a common issue affecting many comparisons. AUTHORS' CONCLUSIONS: Few deaths overall suggest exercise is a safe intervention but means we cannot determine whether exercise reduces mortality or the chance of death or dependency. Cardiorespiratory training and, to a lesser extent mixed training, reduce disability during or after usual stroke care; this could be mediated by improved mobility and balance. There is sufficient evidence to incorporate cardiorespiratory and mixed training, involving walking, within post-stroke rehabilitation programmes to improve fitness, balance and the speed and capacity of walking. The magnitude of VO2 peak increase after cardiorespiratory training has been suggested to reduce risk of stroke hospitalisation by ˜7%. Cognitive function is under-investigated despite being a key outcome of interest for patients. Further well-designed randomised trials are needed to determine the optimal exercise prescription, the range of benefits and any long-term benefits.


Assuntos
Terapia por Exercício/métodos , Aptidão Física , Reabilitação do Acidente Vascular Cerebral , Caminhada/fisiologia , Atividades Cotidianas , Humanos , Pessoa de Meia-Idade , Força Muscular , Consumo de Oxigênio , Desempenho Físico Funcional , Equilíbrio Postural , Ensaios Clínicos Controlados Aleatórios como Assunto , Treinamento Resistido , Acidente Vascular Cerebral/mortalidade , Sobreviventes , Velocidade de Caminhada/fisiologia
18.
Emerg Infect Dis ; 25(12): 2317-2319, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31742526

RESUMO

We report a case of a previously healthy man returning to the United Kingdom from Lithuania who developed rhombencephalitis and myeloradiculitis due to tick-borne encephalitis. These findings add to sparse data on tick-borne encephalitis virus phylogeny and associated neurologic syndromes and underscore the importance of vaccinating people traveling to endemic regions.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos/diagnóstico , Encefalite Transmitida por Carrapatos/virologia , Adulto , Anticorpos Antivirais/imunologia , Biomarcadores , Vírus da Encefalite Transmitidos por Carrapatos/classificação , Vírus da Encefalite Transmitidos por Carrapatos/genética , Genoma Viral , Humanos , Imageamento por Ressonância Magnética , Masculino , Filogenia , Avaliação de Sintomas , Reino Unido
19.
Nanomedicine ; 15(1): 1-11, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189294

RESUMO

The blood-brain barrier (BBB) is a protective endothelial barrier lining the brain microvasculature which prevents brain delivery of therapies against brain diseases. Hence, there is an urgent need to develop vehicles which efficiently penetrate the BBB to deliver therapies into the brain. The drug L-DOPA efficiently and specifically crosses the BBB via the large neutral amino acid transporter (LAT)-1 protein to enter the brain. Thus, we synthesized L-DOPA-functionalized multi-branched nanoflower-like gold nanoparticles (L-DOPA-AuNFs) using a seed-mediated method involving catechols as a direct reducing-cum-capping agent, and examined their ability to cross the BBB to act as brain-penetrating nanovehicles. We show that L-DOPA-AuNFs efficiently penetrate the BBB compared to similarly sized and shaped AuNFs functionalized with a non-targeting ligand. Furthermore, we show that L-DOPA-AuNFs are efficiently internalized by brain macrophages without inducing inflammation. These results demonstrate the application of L-DOPA-AuNFs as a non-inflammatory BBB-penetrating nanovehicle to efficiently deliver therapies into the brain.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Endotélio Vascular/metabolismo , Ouro/química , Levodopa/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Animais , Células Cultivadas , Dopaminérgicos/administração & dosagem , Dopaminérgicos/química , Sistemas de Liberação de Medicamentos , Endotélio Vascular/citologia , Humanos , Levodopa/química , Masculino , Nanopartículas Metálicas/química , Ratos , Ratos Wistar
20.
Euro Surveill ; 24(47)2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31771701

RESUMO

The presence of tick-borne encephalitis virus (TBEV) was detected in a questing tick pool in southern England in September 2019. Hitherto, TBEV had only been detected in a limited area in eastern England. This southern English viral genome sequence is distinct from TBEV-UK, being most similar to TBEV-NL. The new location of TBEV presence highlights that the diagnosis of tick-borne encephalitis should be considered in encephalitic patients in areas of the United Kingdom outside eastern England.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Encefalite Transmitida por Carrapatos/diagnóstico , Ixodes/virologia , RNA Viral/genética , Animais , Cervos , Vírus da Encefalite Transmitidos por Carrapatos/genética , Encefalite Transmitida por Carrapatos/epidemiologia , Inglaterra/epidemiologia , Humanos , Filogenia , Estações do Ano , Estudos Soroepidemiológicos , Sequenciamento Completo do Genoma
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