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1.
Br J Nutr ; 131(2): 219-228, 2024 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-37642175

RESUMO

Gestational diabetes is treated with medical nutrition therapy, delivered by healthcare professionals; however, the optimal diet for affected women is unknown. Randomised controlled trials, such as the DiGest (Dietary Intervention in Gestational Diabetes) trial, will address this knowledge gap, but the acceptability of whole-diet interventions in pregnancy is unclear. Whole-diet approaches reduce bias but require high levels of participant commitment and long intervention periods to generate meaningful clinical outcomes. We aimed to assess healthcare professionals' views on the acceptability of the DiGest dietbox intervention for women with gestational diabetes and to identify any barriers to adherence which could be addressed to support good recruitment and retention to the DiGest trial. Female healthcare professionals (n 16) were randomly allocated to receive a DiGest dietbox containing 1200 or 2000 kcal/d including at least one weeks' food. A semi-structured interview was conducted to explore participants' experience of the intervention. Interviews were audio-recorded, transcribed verbatim and analysed thematically using NVivo software. Based on the findings of qualitative interviews, modifications were made to the dietboxes. Participants found the dietboxes convenient and enjoyed the variety and taste of the meals. Factors which facilitated adherence included participants having a good understanding of study aims and sufficient organisational skills to facilitate weekly meal planning in advance. Barriers to adherence included peer pressure during social occasions and feelings of deprivation or hunger (affecting both standard and reduced calorie groups). Healthcare professionals considered random allocation to a whole-diet replacement intervention to be acceptable and feasible in a clinical environment and offered benefits to participants including convenience.


Assuntos
Diabetes Gestacional , Gravidez , Humanos , Feminino , Estudos de Viabilidade , Dieta , Pessoal de Saúde , Atenção à Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Neuropathol Appl Neurobiol ; 49(2): e12894, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36843390

RESUMO

AIMS: Glioneuronal tumours (GNTs) are poorly distinguished by their histology and lack robust diagnostic indicators. Previously, we showed that common GNTs comprise two molecularly distinct groups, correlating poorly with histology. To refine diagnosis, we constructed a methylation-based model for GNT classification, subsequently evaluating standards for molecular stratification by methylation, histology and radiology. METHODS: We comprehensively analysed methylation, radiology and histology for 83 GNT samples: a training cohort of 49, previously classified into molecularly defined groups by genomic profiles, plus a validation cohort of 34. We identified histological and radiological correlates to molecular classification and constructed a methylation-based support vector machine (SVM) model for prediction. Subsequently, we contrasted methylation, radiological and histological classifications in validation GNTs. RESULTS: By methylation clustering, all training and 23/34 validation GNTs segregated into two groups, the remaining 11 clustering alongside control cortex. Histological review identified prominent astrocytic/oligodendrocyte-like components, dysplastic neurons and a specific glioneuronal element as discriminators between groups. However, these were present in only a subset of tumours. Radiological review identified location, margin definition, enhancement and T2 FLAIR-rim sign as discriminators. When validation GNTs were classified by SVM, 22/23 classified correctly, comparing favourably against histology and radiology that resolved 17/22 and 15/21, respectively, where data were available for comparison. CONCLUSIONS: Diagnostic criteria inadequately reflect glioneuronal tumour biology, leaving a proportion unresolvable. In the largest cohort of molecularly defined glioneuronal tumours, we develop molecular, histological and radiological approaches for biologically meaningful classification and demonstrate almost all cases are resolvable, emphasising the importance of an integrated diagnostic approach.


Assuntos
Neoplasias Encefálicas , Neoplasias do Sistema Nervoso Central , Neoplasias Neuroepiteliomatosas , Radiologia , Humanos , Neoplasias Encefálicas/patologia , Metilação de DNA , Neoplasias Neuroepiteliomatosas/genética , Neoplasias do Sistema Nervoso Central/genética
3.
Mol Cancer ; 21(1): 126, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689207

RESUMO

BACKGROUND: Development of resistance to targeted therapies has tempered initial optimism that precision oncology would improve poor outcomes for cancer patients. Resistance mechanisms, however, can also confer new resistance-specific vulnerabilities, termed collateral sensitivities. Here we investigated anaplastic lymphoma kinase (ALK) inhibitor resistance in neuroblastoma, a childhood cancer frequently affected by activating ALK alterations. METHODS: Genome-wide forward genetic CRISPR-Cas9 based screens were performed to identify genes associated with ALK inhibitor resistance in neuroblastoma cell lines. Furthermore, the neuroblastoma cell line NBLW-R was rendered resistant by continuous exposure to ALK inhibitors. Genes identified to be associated with ALK inhibitor resistance were further investigated by generating suitable cell line models. In addition, tumor and liquid biopsy samples of four patients with ALK-mutated neuroblastomas before ALK inhibitor treatment and during tumor progression under treatment were genomically profiled. RESULTS: Both genome-wide CRISPR-Cas9-based screens and preclinical spontaneous ALKi resistance models identified NF1 loss and activating NRASQ61K mutations to confer resistance to chemically diverse ALKi. Moreover, human neuroblastomas recurrently developed de novo loss of NF1 and activating RAS mutations after ALKi treatment, leading to therapy resistance. Pathway-specific perturbations confirmed that NF1 loss and activating RAS mutations lead to RAS-MAPK signaling even in the presence of ALKi. Intriguingly, NF1 loss rendered neuroblastoma cells hypersensitive to MEK inhibition. CONCLUSIONS: Our results provide a clinically relevant mechanistic model of ALKi resistance in neuroblastoma and highlight new clinically actionable collateral sensitivities in resistant cells.


Assuntos
Neuroblastoma , Medicina de Precisão , Quinase do Linfoma Anaplásico/genética , Linhagem Celular Tumoral , Criança , Humanos , Mutação , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Neuroblastoma/patologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Transdução de Sinais
4.
Mov Disord ; 35(8): 1357-1368, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32472658

RESUMO

BACKGROUND: Juvenile forms of parkinsonism are rare conditions with onset of bradykinesia, tremor and rigidity before the age of 21 years. These atypical presentations commonly have a genetic aetiology, highlighting important insights into underlying pathophysiology. Genetic defects may affect key proteins of the endocytic pathway and clathrin-mediated endocytosis (CME), as in DNAJC6-related juvenile parkinsonism. OBJECTIVE: To report on a new patient cohort with juvenile-onset DNAJC6 parkinsonism-dystonia and determine the functional consequences on auxilin and dopamine homeostasis. METHODS: Twenty-five children with juvenile parkinsonism were identified from a research cohort of patients with undiagnosed pediatric movement disorders. Molecular genetic investigations included autozygosity mapping studies and whole-exome sequencing. Patient fibroblasts and CSF were analyzed for auxilin, cyclin G-associated kinase and synaptic proteins. RESULTS: We identified 6 patients harboring previously unreported, homozygous nonsense DNAJC6 mutations. All presented with neurodevelopmental delay in infancy, progressive parkinsonism, and neurological regression in childhood. 123 I-FP-CIT SPECT (DaTScan) was performed in 3 patients and demonstrated reduced or absent tracer uptake in the basal ganglia. CSF neurotransmitter analysis revealed an isolated reduction of homovanillic acid. Auxilin levels were significantly reduced in both patient fibroblasts and CSF. Cyclin G-associated kinase levels in CSF were significantly increased, whereas a number of presynaptic dopaminergic proteins were reduced. CONCLUSIONS: DNAJC6 is an emerging cause of recessive juvenile parkinsonism-dystonia. DNAJC6 encodes the cochaperone protein auxilin, involved in CME of synaptic vesicles. The observed dopamine dyshomeostasis in patients is likely to be multifactorial, secondary to auxilin deficiency and/or neurodegeneration. Increased patient CSF cyclin G-associated kinase, in tandem with reduced auxilin levels, suggests a possible compensatory role of cyclin G-associated kinase, as observed in the auxilin knockout mouse. DNAJC6 parkinsonism-dystonia should be considered as a differential diagnosis for pediatric neurotransmitter disorders associated with low homovanillic acid levels. Future research in elucidating disease pathogenesis will aid the development of better treatments for this pharmacoresistant disorder. © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Distonia , Transtornos Parkinsonianos , Criança , Dopamina , Distonia/diagnóstico por imagem , Distonia/genética , Proteínas de Choque Térmico HSP40/genética , Homeostase , Humanos , Mutação/genética , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/genética
5.
Am J Hum Genet ; 98(4): 763-71, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27058447

RESUMO

Chorea is a hyperkinetic movement disorder resulting from dysfunction of striatal medium spiny neurons (MSNs), which form the main output projections from the basal ganglia. Here, we used whole-exome sequencing to unravel the underlying genetic cause in three unrelated individuals with a very similar and unique clinical presentation of childhood-onset chorea and characteristic brain MRI showing symmetrical bilateral striatal lesions. All individuals were identified to carry a de novo heterozygous mutation in PDE10A (c.898T>C [p.Phe300Leu] in two individuals and c.1000T>C [p.Phe334Leu] in one individual), encoding a phosphodiesterase highly and selectively present in MSNs. PDE10A contributes to the regulation of the intracellular levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). Both substitutions affect highly conserved amino acids located in the regulatory GAF-B domain, which, by binding to cAMP, stimulates the activity of the PDE10A catalytic domain. In silico modeling showed that the altered residues are located deep in the binding pocket, where they are likely to alter cAMP binding properties. In vitro functional studies showed that neither substitution affects the basal PDE10A activity, but they severely disrupt the stimulatory effect mediated by cAMP binding to the GAF-B domain. The identification of PDE10A mutations as a cause of chorea further motivates the study of cAMP signaling in MSNs and highlights the crucial role of striatal cAMP signaling in the regulation of basal ganglia circuitry. Pharmacological modulation of this pathway could offer promising etiologically targeted treatments for chorea and other hyperkinetic movement disorders.


Assuntos
Coreia/genética , Corpo Estriado/patologia , Mutação , Diester Fosfórico Hidrolases/genética , Sequência de Aminoácidos , Animais , Criança , Coreia/diagnóstico , Corpo Estriado/metabolismo , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Camundongos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Conformação Proteica , Alinhamento de Sequência , Transdução de Sinais , Adulto Jovem
6.
Diabetologia ; 61(7): 1528-1537, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29744539

RESUMO

AIMS/HYPOTHESIS: Women with diabetes remain at increased risk of adverse pregnancy outcomes associated with poor pregnancy preparation. However, women with type 2 diabetes are less aware of and less likely to access pre-pregnancy care (PPC) compared with women with type 1 diabetes. We developed and evaluated a community-based PPC programme with the aim of improving pregnancy preparation in all women with pregestational diabetes. METHODS: This was a prospective cohort study comparing pregnancy preparation measures before and during/after the PPC intervention in women with pre-existing diabetes from 1 June 2013 to 28 February 2017. The setting was 422 primary care practices and ten National Health Service specialist antenatal diabetes clinics. A multifaceted approach was taken to engage women with diabetes and community healthcare teams. This included identifying and sending PPC information leaflets to all eligible women, electronic preconception care templates, online education modules and resources, and regional meetings and educational events. Key outcomes were preconception folic acid supplementation, maternal HbA1c level, use of potentially harmful medications at conception and gestational age at first presentation, before and during/after the PPC programme. RESULTS: A total of 306 (73%) primary care practices actively participated in the PPC programme. Primary care databases were used to identify 5075 women with diabetes aged 18-45 years. PPC leaflets were provided to 4558 (89.8%) eligible women. There were 842 consecutive pregnancies in women with diabetes: 502 before and 340 during/after the PPC intervention. During/after the PPC intervention, pregnant women with type 2 diabetes were more likely to achieve target HbA1c levels ≤48 mmol/mol (6.5%) (44.4% of women before vs 58.5% of women during/after PPC intervention; p = 0.016) and to take 5 mg folic acid daily (23.5% and 41.8%; p = 0.001). There was an almost threefold improvement in 'optimal' pregnancy preparation in women with type 2 diabetes (5.8% and 15.1%; p = 0.021). Women with type 1 diabetes presented for earlier antenatal care during/after PPC (54.0% vs 67.3% before 8 weeks' gestation; p = 0.003) with no other changes. CONCLUSIONS/INTERPRETATION: A pragmatic community-based PPC programme was associated with clinically relevant improvements in pregnancy preparation in women with type 2 diabetes. To our knowledge, this is the first community-based PPC intervention to improve pregnancy preparation for women with type 2 diabetes. DATA AVAILABILITY: Further details of the data collection methodology, individual clinic data and the full audit reports for healthcare professionals and service users are available from https://digital.nhs.uk/data-and-information/clinical-audits-and-registries/our-clinical-audits-and-registries/national-pregnancy-in-diabetes-audit .


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Adolescente , Adulto , Planejamento em Saúde Comunitária , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Ácido Fólico/uso terapêutico , Humanos , Pessoa de Meia-Idade , Cuidado Pré-Concepcional/métodos , Gravidez , Gravidez em Diabéticas , Cuidado Pré-Natal/métodos , Estudos Prospectivos , Adulto Jovem
7.
Am J Hum Genet ; 96(6): 938-47, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-25983243

RESUMO

Myoclonus-dystonia (M-D) is a rare movement disorder characterized by a combination of non-epileptic myoclonic jerks and dystonia. SGCE mutations represent a major cause for familial M-D being responsible for 30%-50% of cases. After excluding SGCE mutations, we identified through a combination of linkage analysis and whole-exome sequencing KCTD17 c.434 G>A p.(Arg145His) as the only segregating variant in a dominant British pedigree with seven subjects affected by M-D. A subsequent screening in a cohort of M-D cases without mutations in SGCE revealed the same KCTD17 variant in a German family. The clinical presentation of the KCTD17-mutated cases was distinct from the phenotype usually observed in M-D due to SGCE mutations. All cases initially presented with mild myoclonus affecting the upper limbs. Dystonia showed a progressive course, with increasing severity of symptoms and spreading from the cranio-cervical region to other sites. KCTD17 is abundantly expressed in all brain regions with the highest expression in the putamen. Weighted gene co-expression network analysis, based on mRNA expression profile of brain samples from neuropathologically healthy individuals, showed that KCTD17 is part of a putamen gene network, which is significantly enriched for dystonia genes. Functional annotation of the network showed an over-representation of genes involved in post-synaptic dopaminergic transmission. Functional studies in mutation bearing fibroblasts demonstrated abnormalities in endoplasmic reticulum-dependent calcium signaling. In conclusion, we demonstrate that the KCTD17 c.434 G>A p.(Arg145His) mutation causes autosomal dominant M-D. Further functional studies are warranted to further characterize the nature of KCTD17 contribution to the molecular pathogenesis of M-D.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Distúrbios Distônicos/genética , Distúrbios Distônicos/patologia , Mutação de Sentido Incorreto/genética , Canais de Potássio/genética , Sequência de Bases , Encéfalo/metabolismo , Mapeamento Cromossômico , Distúrbios Distônicos/metabolismo , Exoma/genética , Feminino , Redes Reguladoras de Genes/genética , Genes Dominantes/genética , Alemanha , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Análise de Sequência de DNA , Transmissão Sináptica/genética , Reino Unido
8.
Brain ; 140(6): 1611-1618, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28430856

RESUMO

Amyotrophic lateral sclerosis is a progressive neurodegenerative disease of motor neurons. About 25 genes have been verified as relevant to the disease process, with rare and common variation implicated. We used next generation sequencing and repeat sizing to comprehensively assay genetic variation in a panel of known amyotrophic lateral sclerosis genes in 1126 patient samples and 613 controls. About 10% of patients were predicted to carry a pathological expansion of the C9orf72 gene. We found an increased burden of rare variants in patients within the untranslated regions of known disease-causing genes, driven by SOD1, TARDBP, FUS, VCP, OPTN and UBQLN2. We found 11 patients (1%) carried more than one pathogenic variant (P = 0.001) consistent with an oligogenic basis of amyotrophic lateral sclerosis. These findings show that the genetic architecture of amyotrophic lateral sclerosis is complex and that variation in the regulatory regions of associated genes may be important in disease pathogenesis.


Assuntos
Esclerose Lateral Amiotrófica/genética , Variação Genética , Herança Multifatorial , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Estudos de Associação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Reino Unido , Adulto Jovem
9.
Brain ; 140(5): 1204-1211, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28334938

RESUMO

Leukodystrophies and genetic leukoencephalopathies are a rare group of disorders leading to progressive degeneration of cerebral white matter. They are associated with a spectrum of clinical phenotypes dominated by dementia, psychiatric changes, movement disorders and upper motor neuron signs. Mutations in at least 60 genes can lead to leukoencephalopathy with often overlapping clinical and radiological presentations. For these reasons, patients with genetic leukoencephalopathies often endure a long diagnostic odyssey before receiving a definitive diagnosis or may receive no diagnosis at all. In this study, we used focused and whole exome sequencing to evaluate a cohort of undiagnosed adult patients referred to a specialist leukoencephalopathy service. In total, 100 patients were evaluated using focused exome sequencing of 6100 genes. We detected pathogenic or likely pathogenic variants in 26 cases. The most frequently mutated genes were NOTCH3, EIF2B5, AARS2 and CSF1R. We then carried out whole exome sequencing on the remaining negative cases including four family trios, but could not identify any further potentially disease-causing mutations, confirming the equivalence of focused and whole exome sequencing in the diagnosis of genetic leukoencephalopathies. Here we provide an overview of the clinical and genetic features of these disorders in adults.


Assuntos
Exoma/genética , Predisposição Genética para Doença/genética , Leucoencefalopatias/diagnóstico , Leucoencefalopatias/genética , Adolescente , Adulto , Feminino , Humanos , Masculino , Mutação , Análise de Sequência de DNA , Adulto Jovem
10.
Brain ; 139(Pt 7): 1904-18, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27217339

RESUMO

The hereditary spastic paraplegias are a heterogeneous group of degenerative disorders that are clinically classified as either pure with predominant lower limb spasticity, or complex where spastic paraplegia is complicated with additional neurological features, and are inherited in autosomal dominant, autosomal recessive or X-linked patterns. Genetic defects have been identified in over 40 different genes, with more than 70 loci in total. Complex recessive spastic paraplegias have in the past been frequently associated with mutations in SPG11 (spatacsin), ZFYVE26/SPG15, SPG7 (paraplegin) and a handful of other rare genes, but many cases remain genetically undefined. The overlap with other neurodegenerative disorders has been implied in a small number of reports, but not in larger disease series. This deficiency has been largely due to the lack of suitable high throughput techniques to investigate the genetic basis of disease, but the recent availability of next generation sequencing can facilitate the identification of disease-causing mutations even in extremely heterogeneous disorders. We investigated a series of 97 index cases with complex spastic paraplegia referred to a tertiary referral neurology centre in London for diagnosis or management. The mean age of onset was 16 years (range 3 to 39). The SPG11 gene was first analysed, revealing homozygous or compound heterozygous mutations in 30/97 (30.9%) of probands, the largest SPG11 series reported to date, and by far the most common cause of complex spastic paraplegia in the UK, with severe and progressive clinical features and other neurological manifestations, linked with magnetic resonance imaging defects. Given the high frequency of SPG11 mutations, we studied the autophagic response to starvation in eight affected SPG11 cases and control fibroblast cell lines, but in our restricted study we did not observe correlations between disease status and autophagic or lysosomal markers. In the remaining cases, next generation sequencing was carried out revealing variants in a number of other known complex spastic paraplegia genes, including five in SPG7 (5/97), four in FA2H (also known as SPG35) (4/97) and two in ZFYVE26/SPG15 Variants were identified in genes usually associated with pure spastic paraplegia and also in the Parkinson's disease-associated gene ATP13A2, neuronal ceroid lipofuscinosis gene TPP1 and the hereditary motor and sensory neuropathy DNMT1 gene, highlighting the genetic heterogeneity of spastic paraplegia. No plausible genetic cause was identified in 51% of probands, likely indicating the existence of as yet unidentified genes.


Assuntos
Proteínas/genética , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/fisiopatologia , Adolescente , Adulto , Linhagem Celular , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Fibroblastos , Humanos , Masculino , Mutação , Linhagem , Fenótipo , Paraplegia Espástica Hereditária/diagnóstico por imagem , Tripeptidil-Peptidase 1 , Reino Unido , Adulto Jovem
12.
Hum Mol Genet ; 21(4): 958-62, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22072393

RESUMO

There have been few definitive examples of gene-gene interactions in humans. Through mutational analyses in 7325 individuals, we report four interactions (defined as departures from a multiplicative model) between mutations in the breast cancer susceptibility genes ATM and CHEK2 with BRCA1 and BRCA2 (case-only interaction between ATM and BRCA1/BRCA2 combined, P = 5.9 × 10(-4); ATM and BRCA1, P= 0.01; ATM and BRCA2, P= 0.02; CHEK2 and BRCA1/BRCA2 combined, P = 2.1 × 10(-4); CHEK2 and BRCA1, P= 0.01; CHEK2 and BRCA2, P= 0.01). The interactions are such that the resultant risk of breast cancer is lower than the multiplicative product of the constituent risks, and plausibly reflect the functional relationships of the encoded proteins in DNA repair. These findings have important implications for models of disease predisposition and clinical translation.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Supressoras de Tumor/genética , Proteínas Mutadas de Ataxia Telangiectasia , Quinase do Ponto de Checagem 2 , Análise Mutacional de DNA , Saúde da Família , Feminino , Humanos , Modelos Genéticos , Linhagem , Reino Unido
13.
Forensic Sci Int ; 356: 111951, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301431

RESUMO

This study assessed the level of nucleic acid persistence on the substrate pre-, and post-swabbing, in order to assess whether biological materials (touch, saliva, semen, and blood) are collected differently depending on the substrate characteristics. A total of 48 samples per deposit and substrate variety (n = 384) were assessed by tracking the persistence of nucleic acid using Diamond™ Nucleic Acid Dye (DD) staining and Polilight photography. The number of DD nucleic acid fluorescent complexes formed post-staining were counted (fluorescent count) and in conjunction with the fluorescence signal intensity (DD nucleic acid complex accumulation) used to estimate the level of nucleic acid persistence on substrates. Touch deposits have shown to be the most persistent deposit with strong adhesion capabilities on both substrate verities. Saliva displayed a higher persistence than semen and/or blood. Semen displayed a high collection efficiency as well as a high fluorescence signal intensity. Blood displayed a low persistence on both substrates with a superior collection efficiency that may also indicate a higher probability to become dislodged from surfaces given a particular activity. Our research has shown that the persistence and recovery of biological deposits is not only measurable but more importantly, may have the potential to be estimated, as such, may build an understanding that can provide valuable guidance for collection efficiency evaluations, and the assessing of the probability of particular profiles, given alternate propositions of means of transfer occurring.


Assuntos
Impressões Digitais de DNA , Ácidos Nucleicos , DNA , Corantes , Tato
14.
Forensic Sci Int ; 354: 111914, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38154427

RESUMO

A comprehensive investigation into the impact of the physical and chemical variables of a substrate on the deposition was conducted to aid in the estimation of the subsequent transfer probabilities of blood and semen. The study focussed on surface roughness, topography, surface free energy (SFE), wettability, and the capacity for protein adsorption. Conjointly, evaluations of the physical and chemical characteristics of blood and seminal deposits were conducted, to assess the fluid dynamics of these non-Newtonian fluids and their adhesion potential to aluminium and polypropylene. A linear range of surface roughness parameters (0.5 - 3.5 µm) were assessed for their impact on the deposit deposition spread and adhesion height, to gather insight into the change in fluid dynamics of non-Newtonian fluids. Blood has shown to produce a uniform adhesion coverage on aluminium across all roughness categories while blood deposited on polypropylene exhibited a strong hydrophobic response from a surface roughness of 2.0 µm and beyond. Interestingly, the deposition height of blood resulted in near identical values, whether deposited onto the hydrophobic polypropylene or the hydrophilic aluminium substrate, illustrating the potential influence of a heightened fibrinogen adsorption effect. Semen deposited on aluminium resulted in concentrated localised deposition regions after reaching a surface roughness of 2.0 µm, highlighting the development of crystal formations afforded by the sodium ion concentration in the seminal fluid. The semen deposited on polypropylene conformed to the substrate contours producing a deposition film that was smoother than the substrate itself, underlining the effects of thixotropic fluid dynamics. Variables identified here establish the complexity observed for non-Newtonian fluids, and the effect protein adsorption may have on the deposition behaviour of blood and seminal deposits and inform questions in relation to the adhesion strength of said deposits and their ability to dislodge (becoming detached upon the application of an external force) from the substrate surface during a potential transfer event.


Assuntos
Líquidos Corporais , Polipropilenos , Propriedades de Superfície , Polipropilenos/análise , Alumínio/análise , Molhabilidade , Líquidos Corporais/química
15.
J Forensic Sci ; 69(3): 1061-1068, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38415957

RESUMO

An investigation into whether the addition of a commonly used anti-coagulant agent like ethylenediaminetetraacetic acid (EDTA) has an impact on the adhesion potential of blood to non-porous substrates was conducted. Two non-porous substrates (aluminum and polypropylene) exhibiting six different surface roughness categories (R1-R6) were used as test substrates upon which either whole blood or blood treated with EDTA was deposited. Samples were exposed to different drying periods (24 hours, 48 hours, and 1 week) before undergoing a tapping agitation experiment in order to evaluate the adhesion to the surface. Clear differences in adhesion potential were observed between whole blood and blood treated with EDTA. Blood treated with EDTA displayed a stronger adhesion strength to aluminum after a drying time of 24 h pre-agitation, while whole blood presented with a stronger adhesion strength at the drying time of 48 h and 1 week. Both EDTA-treated and EDTA-untreated blood was shown to dislodge less easily on polypropylene with the only difference observed on smooth surfaces (0.51-1.50 µm surface roughness). Thus, when conducting transfer studies using smooth hydrophobic substrates like polypropylene or considering the likelihood of transfer given specific case scenarios, differences in adhesion strength of blood due to hydrophobic substrate characteristics and a decreased surface area need to be considered. Overall, whole blood displayed a better adhesion strength to aluminum, emphasizing that indirect transfer probability experiments using EDTA blood on substrates like aluminum should take an increased dislodgment tendency into account in their transfer estimations.


Assuntos
Alumínio , Anticoagulantes , Ácido Edético , Polipropilenos , Propriedades de Superfície , Ácido Edético/farmacologia , Humanos , Anticoagulantes/farmacologia , Adesividade , Manchas de Sangue , Sangue , Interações Hidrofóbicas e Hidrofílicas
16.
Clin Child Psychol Psychiatry ; 28(2): 697-706, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35765954

RESUMO

INTRODUCTION: Youth with suicidal thoughts and behaviours often present to acute emergency care settings for assessment. Timely outpatient follow up may reduce return acute care visits. The primary aim of our study was to describe clinical and contextual differences between youth who do and do not use acute care once connected to outpatient services. METHODS: A 24-month retrospective chart review of suicidal youth aged 13-16 (n = 45) presenting for outpatient mental health treatment. Youth who used acute services during the study period (ASU) or did not (non-ASU) were compared on demographic, risk profile, and mental health service use. RESULTS: The mean age of participants was 14.6 years (73% female). Suicide risk profile at baseline did not differ between groups, but was significantly higher in ASU youth at 24 months. There were more youth in service at the end of the study period in the ASU group compared to the non-ASU group (11% vs 55%). CONCLUSION: Youth who do continue to access acute services may be at higher risk of suicidality even after outpatient treatment. Although it is unclear whether this is linked to outpatient engagement, it raises further questions about this population and how they respond to community based mental healthcare.


Assuntos
Serviços de Saúde Mental , Ideação Suicida , Humanos , Adolescente , Feminino , Masculino , Estudos Retrospectivos , Assistência Ambulatorial
17.
PLoS One ; 18(9): e0292094, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37756288

RESUMO

BACKGROUND: Undiagnosed diabetes in pregnancy is associated with stillbirth and perinatal complications, but standard testing for gestational diabetes using the oral glucose tolerance test (OGTT) is impractical and exacerbates healthcare inequalities. There is an urgent need to improve the accuracy, acceptability and accessibility of glucose testing in pregnancy. We qualitatively assessed the feasibility and acceptability of two alternative home-based methods of glucose testing in pregnant women, using continuous glucose monitoring (CGM), with or without a home-based OGTT. METHODS: We recruited women with a singleton pregnancy at 28 weeks' gestation with ≥1 risk factor for gestational diabetes attending antenatal glucose testing. A Dexcom G6 CGM device was sited and women were asked to take a 75g OGTT solution (Rapilose) on day 4 after an overnight fast. Qualitative interviews were performed with 20 participants using video conferencing according to a semi-structured interview schedule and thematically analysed using NVIVO software. RESULTS: 92 women were recruited; 73 also underwent a home OGTT. Women had an average of 6.9 days of glucose monitoring and found the CGM painless, easy to use with few or no adverse events. During the qualitative study, the main themes identified were reassurance and convenience. All women interviewed would recommend CGM and a home OGTT for diagnosis of gestational diabetes. CONCLUSIONS: CGM with or without a home OGTT is feasible and acceptable to pregnant women for diagnosis of gestational diabetes and offered advantages of convenience and reassurance. Further work is needed to clarify diagnostic thresholds for gestational diabetes using CGM metrics.


Assuntos
Diabetes Gestacional , Gravidez , Feminino , Humanos , Diabetes Gestacional/diagnóstico , Automonitorização da Glicemia , Estudos de Viabilidade , Estudos Prospectivos , Glicemia , Glucose
18.
Forensic Sci Int ; 343: 111546, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36621057

RESUMO

An in-depth study into the physical substrate characteristics such as substrate surface roughness, topography, and physicochemical characteristics like wettability and surface free energy (SFE) was conducted to investigate the impact on the deposition and adherence of touch and salivary deposits on aluminium and polypropylene. A robust protocol was established to generate a set of substrates with a controlled linear surface roughness range (0.5-3.5 µm) in order to identify the impact of surface roughness on DNA transfer, persistence, prevalence, and recovery (DNA-TPPR). The polypropylene substrate was shown to produce fibres when artificially roughened, becoming more prominent at a higher surface roughness range, and has shown to have a direct impact on the distribution of salivary and touch deposits. At the low to moderate surface roughness range 0.5-2.0 µm, salivary and touch deposits have generally shown to follow the topographical features of the substrate they were deposited on, before a plateau of the surface roughness measure on the deposit was observed, indicating that a saturation point was reached and the grooves in the substrate were beginning to fill. Touch deposits have shown to maintain a consistent deposition height pre-surface roughness threshold, irrespective of substrate surface roughness while the deposition height of salivary deposits was heavily influenced by substrate surface roughness and topography. The substrate SFE, wettability, hydrophobicity, and the surface tension of the deposit was shown to drive the adhesion properties of the saliva and touch deposits on the respective substrates, and it was observed that this may be of importance for the improvement of the current DNA-TPPR understanding, DNA sampling protocols, and DNA transfer considerations within casework.


Assuntos
Polipropilenos , Tato , Molhabilidade , DNA/genética , Tensão Superficial , Propriedades de Superfície
19.
Eur J Med Chem ; 259: 115637, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37524009

RESUMO

A series of 3-methoxy-2-phenylimidazo[1,2-b]pyridazine derivatives which were highly active against autoluminescent Mycobacterium tuberculosis (Mtb) and Mycobacterium marinum (Mm) in an in vitro assay were identified. SAR analysis showed that the most active compounds, which included a phenyl group bearing fluoro substituent(s) at C2, a methoxy function at C3, and a benzyl-heteroatom moiety at C6, exhibited in vitro MIC90 values generally around 0.63-1.26 µM against Mtb and Mm. However, these compounds were inactive against Mtb in vivo (mice), and investigations revealed very short metabolic half-lives (<10 min) when incubated with mouse liver microsomes. Multiple observations of side products produced from oxidative cleavage of the imidazole moiety during the chemical synthesis work suggested that this is a likely metabolic pathway leading to the lack of observed activity in vivo.


Assuntos
Mycobacterium marinum , Mycobacterium tuberculosis , Piridazinas , Animais , Camundongos , Antituberculosos/farmacologia , Antituberculosos/química , Piridazinas/química , Testes de Sensibilidade Microbiana
20.
Forensic Sci Int ; 330: 111096, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34794062

RESUMO

A targeted sampling approach of latent DNA, deposited when a person makes contact with a surface, can prove challenging during crime scene or evidence processing, with the sampling of latent DNA often relying on the expert judgement from crime scene officers and forensic examiners. As such, the ability to use the quick and robust screening tool Diamond™ Nucleic Acid Dye (DD) was explored, with a focus on the visualisation of latent DNA on non-porous substrates, namely polypropylene, acrylic, aluminium, PVC composite material, glass, and crystalline silicon. The application of DD was performed according to methods reported in literature, where 10 µL of the dye solution (20-fold dilution of DD in 75% EtOH) was applied onto a variety of non-porous substrates via a micropipette and then subsequently visualised using a portable fluorescence microscope. It was discovered that there was scope for improvement in the reported methods due to the observation of crystal formations on all test substrates upon drying of the DD, resulting in the impaired visualisation of latent DNA and fingerprint detail. Thus, changes to the EtOH water ratio of the dye solution, and changes to the mode of dye application from a micropipette to a spray application, were explored to improve the drying time of the dye and mitigate the formation of crystals. While changes to the EtOH water ratio did not improve the overall drying time, the mode of dye application enhanced visualisation, with a spray application eliminating the formation of crystals no matter the EtOH water ratio. Visualisation with a portable Dino-Lite and Zeiss Widefield fluorescence microscope were also explored, with the Zeiss Widefield fluorescence microscope proving to be useful in whole print imaging and a more efficient imaging tool in a laboratory setting.


Assuntos
Medicina Legal , Ácidos Nucleicos , DNA , Impressões Digitais de DNA , Dermatoglifia , Corantes Fluorescentes , Humanos , Repetições de Microssatélites , Tato , Água
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