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1.
Echo Res Pract ; 11(1): 7, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424646

RESUMO

INTRODUCTION: Athletic training can result in electrical and structural changes of the right ventricle that may mimic phenotypical features of arrhythmogenic right ventricular cardiomyopathy (ARVC), such as T-wave inversion and right heart dilatation. An erroneous interpretation may have consequences ranging from false reassurance in an athlete vulnerable to cardiac arrhythmias, to unnecessary sports restriction in a healthy individual. The primary aim of this study was to define normal RV dimension reference ranges for academy adolescent footballers of different ethnicities. Secondary aims include analysis of potential overlap between this adolescent group with ARVC criteria and comparison with normal adult ranges. RESULTS: Electrocardiographic (ECG) and echocardiographic data of 1087 academy male footballers aged between 13 and 18 years old (mean age 16.0 ± 0.5 years), attending mandatory cardiac screening were analysed. Ethnicity was categorised as white (n = 826), black (African/Caribbean; n = 166) and mixed-race (one parent white and one parent black; n = 95). Arrhythmogenic right ventricular cardiomyopathy major criteria for T-wave inversion was seen in 3.3% of the cohort. This was more prevalent in black footballers (12%) when compared to mixed race footballers (6.3%) or white footballers (1%), P < 0.05. Up to 59% of the cohort exceeded adult reference ranges for some of the right ventricular parameters, although values were similar to those seen in adult footballers. There were no differences in right ventricular dimensions between ethnicities. In particular, the right ventricular outflow tract diameter would fulfil major criteria for ARVC dimension in 12% of footballers. Overall, 0.2% of the cohort would fulfil diagnosis for 'definite' arrhythmogenic right ventricular cardiomyopathy and 2.2% would fulfil diagnosis for 'borderline' arrhythmogenic right ventricular cardiomyopathy for RV dimensions and ECG changes. This was seen more frequently in black footballers (9.9%) than mixed race footballers (3.9%) or white footballer (0.6%), P < 0.05. Among athletes meeting definite or borderline arrhythmogenic right ventricular cardiomyopathy criteria, no cardiomyopathy was identified after comprehensive clinical assessment, including with cardiac magnetic resonance imaging, exercise testing, ambulatory electrocardiograms and familial evaluation. CONCLUSION: Right heart sizes in excess of accepted adult ranges occurred in as many as one in two adolescent footballers. Structural adaptations in conjunction with anterior T-wave inversion may raise concern for ARVC, highlighting the need for evaluation in expert settings.

2.
Clin Radiol ; 78(12): e941-e949, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37788968

RESUMO

AIM: To investigate how magnetic resonance imaging (MRI) examinations are protocolled in tertiary paediatric neuroradiology centres around the UK for some of the more common presentations encountered in paediatric neuroradiology, and to identify any variations of note. MATERIALS AND METHODS: All 19 UK tertiary paediatric neuroradiology centres registered with the British Society of Neuroradiologists-Paediatric Group were contacted and asked if they could provide a copy of their standard MRI protocols. Twelve responded (63%) and 10 of the more common presentations were selected and the standard acquired sequences obtained at each participating centre were compared. Where available the collated protocols were also compared against current published guidance. RESULTS: The basic sequences carried out by centres around the UK are similar; however, there are lots of variations overall. The only standardised protocol currently being implemented nationally in paediatric imaging is that for brain tumours. Otherwise, chosen protocols are generally dependent on the preferences and technical capabilities of individual centres. Suggested published protocols also exist for non-accidental injury (NAI), multiple sclerosis, epilepsy, and head and neck imaging. CONCLUSIONS: The differences in MRI protocolling depend in part on technical capabilities and in part on the experience and preferences of the paediatric neuroradiologists at each centre. For most presentations, there is no consensus as to what constitutes the perfect protocol. The present results will be useful for specialist centres who may wish to review their current protocols, and for more generalist centres to use as a reference to guide their MRI protocolling.


Assuntos
Neoplasias Encefálicas , Hospitais Pediátricos , Criança , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Centros de Atenção Terciária , Reino Unido
3.
Nat Commun ; 13(1): 6975, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379931

RESUMO

Histone methylation is an important post-translational modification that plays a crucial role in regulating cellular functions, and its dysregulation is implicated in cancer and developmental defects. Therefore, systematic characterization of histone methylation is necessary to elucidate complex biological processes, identify biomarkers, and ultimately, enable drug discovery. Studying histone methylation relies on the use of antibodies, but these suffer from lot-to-lot variation, are costly, and cannot be used in live cells. Chromatin-modification reader domains are potential affinity reagents for methylated histones, but their application is limited by their modest affinities. We used phage display to identify key residues that greatly enhance the affinities of Cbx chromodomains for methylated histone marks and develop a general strategy for enhancing the affinity of chromodomains of the human Cbx protein family. Our strategy allows us to develop powerful probes for genome-wide binding analysis and live-cell imaging. Furthermore, we use optimized chromodomains to develop extremely potent CRISPR-based repressors for tailored gene silencing. Our results highlight the power of engineered chromodomains for analyzing protein interaction networks involving chromatin and represent a modular platform for efficient gene silencing.


Assuntos
Histonas , Lisina , Humanos , Metilação , Histonas/metabolismo , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Cromatina/genética
5.
J Hosp Infect ; 126: 93-102, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35562072

RESUMO

BACKGROUND: Healthcare-associated infections (HAIs) are not present on admission but are contracted while a patient is undergoing hospital treatment. While the prevalence of HAIs, and their causes and treatments have been researched in various contexts to date, patients' perspectives of contracting and living with the consequences of an HAI remain under-researched. OBJECTIVE: To explore patients' experiences of having an HAI. METHODS: A qualitative phenomenological study that drew on data from semi-structured interviews was conducted in order to explore the lived experiences of patients who had recently contracted an HAI while in hospital. Participants were recruited from two Australian hospitals in 2019 and 2021. Telephone interviews were conducted with 10 participants by two research team members, and transcripts from these interviews were analysed qualitatively using a thematic coding process to identify the patients' perspectives of contracting an HAI. RESULTS: The participants had a range of different HAIs. The participants described how the experience of having an HAI can be very isolating and distressing from the patient's perspective, with life-long implications. This contributes to understanding of the way in which patients are impacted emotionally and mentally as a result of contracting an HAI. CONCLUSION: There is a need for improved, person-centred communication about the source, treatment and prognosis of HAIs. The findings from this study indicate the importance of considering patients' voices in their own health care.


Assuntos
Infecção Hospitalar , Austrália/epidemiologia , Comunicação , Infecção Hospitalar/epidemiologia , Atenção à Saúde , Hospitais , Humanos , Pesquisa Qualitativa
6.
Toxicol In Vitro ; 69: 104997, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32896591

RESUMO

Electronic nicotine delivery systems (ENDS) are a rapidly growing global market advertised as a safer alternative to combustible cigarettes. However, comprehensive investigations of END aerosol physicochemical and toxicological properties have not been fully explored across brands to assess relative safety. In this study, we evaluated aerosols collected from three ENDS - Juul Fruit Medley (5% nicotine), Logic Power (2.4% nicotine), and Mistic (1.8% nicotine). ENDS aerosols were generated using standard machine puffing regimen and collected with a novel fluoropolymer condensation trap. Triple quadrupole-inductively coupled plasma-mass determined the presence of heavy metals in collected aerosols. The toxicological effects of ENDS aerosols on normal human bronchial epithelial cells (NHBE) were investigated using cellular viability, reactive oxygen species, oxidative stress assays, along with DNA damage assessments using the CometChip©. Results indicated the total metal concentrations within collected ENDS aerosols were higher for Mistic and Logic compared to Juul. Logic Power aerosols elicited higher reactive oxygen species levels than Mistic and Juul in NHBE after 24-h exposure. Similar dose-dependent reductions of cellular viability and total glutathione were found for each exposure. However, Logic and Juul aerosols caused greater single stranded DNA damage compared to Mistic. Our study indicates that regardless of brand, ENDS aerosols are toxic to upper airway epithelial cells and may pose a potential respiratory hazard to occasional and frequent users.


Assuntos
Brônquios/citologia , Vapor do Cigarro Eletrônico/toxicidade , Sistemas Eletrônicos de Liberação de Nicotina , Células Epiteliais/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Vapor do Cigarro Eletrônico/análise , Células Epiteliais/metabolismo , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
7.
Inhal Toxicol ; 31(9-10): 357-367, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31779509

RESUMO

Objective: The aerosolization of common nano-enabled consumer products such as cosmetics has significantly increased engineered nanoparticle inhalation risks. While several studies have investigated the impact of cosmetic dermal exposures, inhalation hazards of aerosolized cosmetics are much less known but could pose considerable harm to users due to potential co-exposure of nanoparticles and other product components.Materials and Methods: In this study, we developed a fully automated aerosol generation system to examine the aerosol properties of four aerosolized nano-enabled cosmetics using real-time monitoring and sampling instrumentation. Physicochemical characterization of aerosols was conducted using scanning electron microscopy coupled with energy dispersive x-ray spectroscopy (SEM-EDX). Characterization and calibration of animal exposure pods coupled to the system were also performed by measuring and comparing particle concentrations between pods.Results and Discussion: Results show peak emissions are shade dependent and varied between 12,000-22,000 particles/cm3 with modal diameters ranging from 36 nm-1.3 µm. SEM-EDX analysis determined that the original products and collected aerosols have similar morphological features consisting of micron-sized particles decorated with nanoparticles and crystalline structures. Mean total particle concentration in pods at 5 and 10 mg/m3 target levels were 2.22E + 05 #/cm3 and 4.33E + 05 #/cm3, respectively, with <10% variability between pods.Conclusions: The fully automated exposure platform described herein provides reproducible aerosol generation, conforms to recommended guidelines on chemical testing, and therefore is suitable for future in vivo toxicological assessments to examine potential respiratory hazards of aerosolized nano-enabled consumer products.


Assuntos
Aerossóis/química , Cosméticos/química , Exposição por Inalação , Nanoestruturas/química , Testes de Toxicidade/instrumentação , Testes de Toxicidade/métodos , Humanos
8.
Leukemia ; 32(4): 882-889, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29089643

RESUMO

Despite advances in our understanding of the molecular basis for particular subtypes of acute myeloid leukemia (AML), effective therapy remains a challenge for many individuals suffering from this disease. A significant proportion of both pediatric and adult AML patients cannot be cured and since the upper limits of chemotherapy intensification have been reached, there is an urgent need for novel therapeutic approaches. The transcription factor c-MYB has been shown to play a central role in the development and progression of AML driven by several different oncogenes, including mixed lineage leukemia (MLL)-fusion genes. Here, we have used a c-MYB gene expression signature from MLL-rearranged AML to probe the Connectivity Map database and identified mebendazole as a c-MYB targeting drug. Mebendazole induces c-MYB degradation via the proteasome by interfering with the heat shock protein 70 (HSP70) chaperone system. Transient exposure to mebendazole is sufficient to inhibit colony formation by AML cells, but not normal cord blood-derived cells. Furthermore, mebendazole is effective at impairing AML progression in vivo in mouse xenotransplantation experiments. In the context of widespread human use of mebendazole, our data indicate that mebendazole-induced c-MYB degradation represents a safe and novel therapeutic approach for AML.


Assuntos
Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Mebendazol/farmacologia , Proteólise/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myb/metabolismo , Animais , Criança , Feminino , Humanos , Lactente , Masculino , Camundongos , Oncogenes/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo
9.
J Anim Sci ; 95(10): 4260-4273, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29108061

RESUMO

Genetic correlations between 29 wool production and quality traits and 25 meat quality and nutritional value traits were estimated for Merino sheep from an Information Nucleus (IN). Genetic correlations among the meat quality and nutritional value traits are also reported. The IN comprised 8 flocks linked genetically and managed across a range of sheep production environments in Australia. The wool traits included over 5,000 yearling and 3,700 adult records for fleece weight, fiber diameter, staple length, staple strength, fiber diameter variation, scoured wool color, and visual scores for breech and body wrinkle. The meat quality traits were measured on samples from the and included over 1,200 records from progeny of over 170 sires for intramuscular fat (IMF), shear force of meat aged for 5 d (SF5), 24 h postmortem pH (pHLL; also measured in the , pHST), fresh and retail meat color and meat nutritional value traits such as iron and zinc levels, and long-chain omega-3 and omega-6 polyunsaturated fatty acid levels. Estimated heritabilities for IMF, SF5, pHLL, pHST, retail meat color lightness (), myoglobin, iron, zinc and across the range of long-chain fatty acids were 0.58 ± 0.11, 0.10 ± 0.09, 0.15 ± 0.07, 0.20 ± 0.10, 0.59 ± 0.15, 0.31 ± 0.09, 0.20 ± 0.09, 0.11 ± 0.09, and range of 0.00 (eicosapentaenoic, docosapentaenoic, and arachidonic acids) to 0.14 ± 0.07 (linoleic acid), respectively. The genetic correlations between the wool production and meat quality traits were low to negligible and indicate that wool breeding programs will have little or no effect on meat quality. There were moderately favorable genetic correlations between important yearling wool production traits and the omega-3 fatty acids that were reduced for corresponding adult wool production traits, but these correlations are unlikely to be important in wool/meat breeding programs because they have high SE, and the omega-3 traits have little or no genetic variance. Significant genetic correlations among the meat quality traits included IMF with SF5 (-0.76 ± 0.24), fresh meat color * (0.50 ± 0.18), and zinc (0.41 ± 0.19). Selection to increase IMF will improve meat tenderness and color which may address some of the issues with Merino meat quality. These estimated parameters allow Merino breeders to combine wool and meat objectives without compromising meat quality.


Assuntos
Carne/normas , Ovinos/genética , Lã/normas , Animais , Austrália , Peso Corporal/genética , Cruzamento , Cor , Ácidos Graxos/análise , Feminino , Ferro/análise , Masculino , Valor Nutritivo/genética , Fenótipo , Ovinos/fisiologia , Zinco/análise
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