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2.
Stem Cell Rev Rep ; 20(3): 797-815, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38316679

RESUMO

Stem cell-based therapy is a potential alternative strategy for brain repair, with neural stem cells (NSC) presenting as the most promising candidates. Obtaining sufficient quantities of NSC for clinical applications is challenging, therefore alternative cell types, such as neural crest-derived dental pulp stem cells (DPSC), may be considered. Human DPSC possess neurogenic potential, exerting positive effects in the damaged brain through paracrine effects. However, a method for conversion of DPSC into NSC has yet to be developed. Here, overexpression of octamer-binding transcription factor 4 (OCT4) in combination with neural inductive conditions was used to reprogram human DPSC along the neural lineage. The reprogrammed DPSC demonstrated a neuronal-like phenotype, with increased expression levels of neural markers, limited capacity for sphere formation, and enhanced neuronal but not glial differentiation. Transcriptomic analysis further highlighted the expression of genes associated with neural and neuronal functions. In vivo analysis using a developmental avian model showed that implanted DPSC survived in the developing central nervous system and respond to endogenous signals, displaying neuronal phenotypes. Therefore, OCT4 enhances the neural potential of DPSC, which exhibited characteristics aligning with neuronal progenitors. This method can be used to standardise DPSC neural induction and provide an alternative source of neural cell types.


Assuntos
Polpa Dentária , Células-Tronco , Humanos , Diferenciação Celular , Fator de Transcrição 4/metabolismo , Neurogênese
3.
Br J Sports Med ; 58(8): 435-443, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38408858

RESUMO

OBJECTIVE: This study aims to investigate how athlete ethnicity is discussed in the inclusion and exclusion criteria, methodology, findings, and conclusions of research focused on menstrual health in sports science and medicine. DESIGN: A scoping review of sports-based research conducted on athletes related to (1) menstrual health and ethnicity, (2) how researchers include/exclude participants based on ethnicity and (3) how ethnicity is discussed. DATA SOURCES: Electronic search of PubMed and ProQuest. ELIGIBILITY CRITERIA: Articles were included if they met the following criteria: (1) published before September 2023, (2) published in peer-reviewed journals, (3) participants were women athletes, (4) published in English and (5) relating to menstrual health. Articles were assessed as good, fair or poor quality using the Inclusion of Participant Ethnicity Quality Assessment Criteria. RESULTS: From the 1089 studies available from the initial database search, 55 studies considered ethnicity. Nine studies met the inclusion criteria and were assessed as either good (22%), fair (44%) or poor (33%) in quality in their consideration of athlete ethnicity. 81% of research articles on menstrual health in sports do not consider athlete ethnicity, and when ethnicity is discussed, it rarely meets the criteria for cultural safety in the research process. Most studies did not factor ethnicity into the analysis and lacked cultural considerations in the research design and interventions. CONCLUSION: More careful inclusion of ethnicity in sports menstrual health-related research and recognition of social and cultural influences on health and research outcomes for indigenous and other ethnic minority groups is needed. Such research is required to support coaches, medical personnel and support staff in designing culturally safe environments for sportswomen from diverse cultural and ethnic backgrounds.


Assuntos
Etnicidade , Esportes , Humanos , Feminino , Masculino , Grupos Minoritários , Atletas
4.
J Sci Med Sport ; 26(12): 659-666, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37932202

RESUMO

OBJECTIVES: To report findings from the High Performance Sport New Zealand cardiac screening programme, including comparisons between sexes and ethnicities. DESIGN: Retrospective cohort study. METHODS: Elite Olympic-sport athletes were screened (2012-2022) with personal/family history, physical examination, resting 12-lead ECG and followed from the date of first screening until July 2022. An audit reviewed screening records, including demographic data, ECGs, follow-up and diagnoses. Flagged/equivocal ECGs were re-reviewed (International Criteria). RESULTS: 2075 ECGs from 1189 athletes (53 % female, mean age 21 years; 83 % European, 9 % Maori, 5 % Pacific Islander, 3 % other) were included. No athletes retired for cardiac reasons; there were no cardiac deaths or major cardiac incidents (mean follow-up from first screening: 6.1 years (range: 0.6-10.9 years)). Diagnoses included Wolff-Parkinson-White (WPW) syndrome (0.7 %) and cardiomyopathies (0.3 %). Overall, 3.5 % of ECGs were abnormal, with ECGs of females more commonly abnormal (4.4 % vs 2.5 %, p = 0.02) and with a higher proportion of ECGs with abnormal T-wave inversion (TWI) (3.1 % vs 0.9 %, p < 0.001) compared to males. Of the abnormal TWI in females (all aged ≥16 years), 47 % was limited to V1-V3 with no other abnormalities. Abnormality rates were similar between Maori, Pacific Islander and European athlete ECGs. CONCLUSIONS: WPW was the most frequent diagnosis, with very little cardiomyopathy found. The proportion of abnormal ECGs was low overall, but higher in females. This was driven by anterior TWI in V1-V3 which was not associated with diagnoses of conditions associated with sudden cardiac death (SCD). There was no difference in the proportion of abnormal ECGs of Maori or Pacific Island athletes compared to European athletes.


Assuntos
Atletas , Morte Súbita Cardíaca , Cardiopatias , Feminino , Humanos , Masculino , Adulto Jovem , Morte Súbita Cardíaca/prevenção & controle , Eletrocardiografia , Cardiopatias/diagnóstico , Nova Zelândia , Estudos Retrospectivos
5.
Artigo em Inglês | MEDLINE | ID: mdl-37754639

RESUMO

The Ottawa Charter identifies that multiple levels of government, non-government, community, and other organizations should work together to facilitate health promotion, including in acute settings such as hospitals. We outline a method and protocol to achieve this, namely an Action Research (AR) framework for an Animal Assisted Intervention (AAI) in a tertiary health setting. Dogs Offering Support after Stroke (DOgSS) is an AR study at a major tertiary referral hospital. AAI has been reported to improve mood and quality of life for patients in hospitals. Our project objectives included applying for funding, developing a hospital dog visiting Action Research project, and, subsequent to ethics and governance approvals and finance, undertaking and reporting on the Action Research findings. The Action Research project aimed to investigate whether AAI (dog-visiting) makes a difference to the expressed mood of stroke patients and their informal supports (visiting carers/family/friends), and also the impact these visits have on hospital staff and volunteers, as well as the dog handler and dog involved. We provide our protocol for project management and operations, setting out how the project is conducted from conception to assess human and animal wellbeing and assist subsequent decision-making about introducing dog-visiting to the Stroke Unit. The protocol can be used or adapted by other organizations to try to avoid pitfalls and support health promotion in one of the five important action areas of the Ottawa Charter, namely that of reorienting health services.


Assuntos
Qualidade de Vida , Acidente Vascular Cerebral , Humanos , Animais , Cães , Afeto , Promoção da Saúde , Acidente Vascular Cerebral/terapia , Centros de Atenção Terciária
6.
Artigo em Inglês | MEDLINE | ID: mdl-37239529

RESUMO

Dogs may provide humans with a range of physical, mental and social benefits. Whilst there is growing scientific evidence of benefits to humans, there has been less focus on the impact to canine health, welfare and ethical considerations for the dogs. The importance of animal welfare is increasingly acknowledged, indicating that the Ottawa Charter should be extended to include the welfare of non-human animals supporting the promotion of human health. Therapy dog programmes are delivered across a variety of settings including hospitals, aged care facilities and mental health services, highlighting the important role they play in human health outcomes. Research has shown that that there are biomarkers for stress in humans and other animals engaged in human-animal interactions. This review aims to assess the impact of human-animal interactions on therapy dogs engaged in providing support to human health. While challenging, it is paramount to ensure that, within the framework of One Welfare, the welfare of therapy dogs is included, as it is a key factor for future sustainability. We identified a range of concerns due to the lack of guidelines and standards to protect the wellbeing of the dogs engaged in these programmes. Extension of the Ottawa Charter to include the welfare of non-human animals with leveraging through a One Welfare approach would promote animal and human health beyond current boundaries.


Assuntos
Promoção da Saúde , Animais de Terapia , Humanos , Animais , Cães , Idoso , Bem-Estar do Animal
7.
Animals (Basel) ; 13(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36978653

RESUMO

The social determinants of health (SDH) focus on the social, physical and economic factors that impact human health. Studies have revealed that animal guardians face a range of challenges in attaining positive welfare outcomes for their companion animals, which can be influenced by socioeconomic and environmental factors. Despite this, there is a lack of research specifically exploring the relationship between SDH and animal welfare outcomes. Given that the SDH impact on humans, which in turn directly impacts on their companion animal, it is important to adapt an SDH framework for companion animal welfare by characterising the impact of the SDH on companion animal guardians in their attempts to care for their animals and, by extension, the associated welfare outcomes. This paper explores how these human health determinants may impact animal welfare and the possible challenges that may arise for the guardian when attempting to meet their companion animal's welfare needs. By integrating the SDH with other key frameworks, including the five domains model of animal welfare, through multidisciplinary collaboration, this framework can be used to inform future programs aiming to improve animal welfare.

8.
Animals (Basel) ; 12(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35953965

RESUMO

The nomenclature used to describe animals working in roles supporting people can be confusing. The same term may be used to describe different roles, or two terms may mean the same thing. This confusion is evident among researchers, practitioners, and end users. Because certain animal roles are provided with legal protections and/or government-funding support in some jurisdictions, it is necessary to clearly define the existing terms to avoid confusion. The aim of this paper is to provide operationalized definitions for nine terms, which would be useful in many world regions: "assistance animal", "companion animal", "educational/school support animal", "emotional support animal", "facility animal", "service animal", "skilled companion animal", "therapy animal", and "visiting/visitation animal". At the International Society for Anthrozoology (ISAZ) conferences in 2018 and 2020, over 100 delegates participated in workshops to define these terms, many of whom co-authored this paper. Through an iterative process, we have defined the nine terms and explained how they differ from each other. We recommend phasing out two terms (i.e., "skilled companion animal" and "service animal") due to overlap with other terms that could potentially exacerbate confusion. The implications for several regions of the world are discussed.

9.
Gen Dent ; 70(5): 49-53, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35993933

RESUMO

Finishing and polishing of composite resin restorations may cause damage to the bordering enamel. Although many studies have investigated the effect of polish on restorative materials, few have quantified the effect on bordering enamel. The objective of this study was to compare enamel loss surrounding composite restorations after finishing and polishing sequences. The null hypothesis was that there would be no difference in enamel loss between different finishing and polishing sequences. Class V preparations on the buccal and lingual surfaces of 15 extracted human molars were restored with a composite resin and assigned to 1 of 2 finishing and polishing sequences, so that each tooth underwent both sequences (n = 15 per sequence). In sequence 1, a tungsten carbide finishing bur and aluminum oxide polishing discs were used; in sequence 2, a diamond finishing bur, aluminum oxide-impregnated finishing cup, and diamond-impregnated polishing cup were used. Tooth surfaces were scanned with an optical scanner after preparation, finishing, initial polishing, and final polishing. The finishing and polishing scans were aligned to the preparation scan using Cumulus software. The depth of enamel surface loss was calculated and statistically analyzed (α = 0.05; paired t test). Most enamel loss (mean [SD]) resulted from the finishing step with the tungsten carbide bur (51.8 [21.3] µm) or diamond bur (43.3 [12.6] µm). Each polishing step increased mean enamel loss by only a few microns. There was no statistically significant difference between the 2 finishing and polishing sequences. The majority of enamel damage during finishing and polishing of composite resin restorations resulted from the finishing burs. Little enamel was removed by either of the tested composite resin polishing systems.


Assuntos
Resinas Compostas , Polimento Dentário , Óxido de Alumínio , Resinas Compostas/efeitos adversos , Esmalte Dentário , Polimento Dentário/métodos , Restauração Dentária Permanente/efeitos adversos , Restauração Dentária Permanente/métodos , Diamante , Humanos , Polônia , Propriedades de Superfície
10.
BMJ Open ; 12(4): e045908, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365506

RESUMO

INTRODUCTION: Transient ischaemic attack (TIA) may be a warning sign of stroke and difficult to differentiate from minor stroke and TIA-mimics. Urgent evaluation and diagnosis is important as treating TIA early can prevent subsequent strokes. Recent improvements in mass spectrometer technology allow quantification of hundreds of plasma proteins and lipids, yielding large datasets that would benefit from different approaches including machine learning. Using plasma protein, lipid and radiological biomarkers, our study will develop predictive algorithms to distinguish TIA from minor stroke (positive control) and TIA-mimics (negative control). Analysis including machine learning employs more sophisticated modelling, allowing non-linear interactions, adapting to datasets and enabling development of multiple specialised test-panels for identification and differentiation. METHODS AND ANALYSIS: Patients attending the Emergency Department, Stroke Ward or TIA Clinic at the Royal Adelaide Hospital with TIA, minor stroke or TIA-like symptoms will be recruited consecutively by staff-alert for this prospective cohort study. Advanced neuroimaging will be performed for each participant, with images assessed independently by up to three expert neurologists. Venous blood samples will be collected within 48 hours of symptom onset. Plasma proteomic and lipid analysis will use advanced mass spectrometry (MS) techniques. Principal component analysis and hierarchical cluster analysis will be performed using MS software. Output files will be analysed for relative biomarker quantitative differences between the three groups. Differences will be assessed by linear regression, one-way analysis of variance, Kruskal-Wallis H-test, χ2 test or Fisher's exact test. Machine learning methods will also be applied including deep learning using neural networks. ETHICS AND DISSEMINATION: Patients will provide written informed consent to participate in this grant-funded study. The Central Adelaide Local Health Network Human Research Ethics Committee approved this study (HREC/18/CALHN/384; R20180618). Findings will be disseminated through peer-reviewed publication and conferences; data will be managed according to our Data Management Plan (DMP2020-00062).


Assuntos
Ataque Isquêmico Transitório , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , Lipídeos , Aprendizado de Máquina , Espectrometria de Massas , Neuroimagem , Estudos Prospectivos , Proteômica
11.
G3 (Bethesda) ; 12(3)2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35100349

RESUMO

How and to what degree gene duplication events create regulatory innovation, redundancy, or neofunctionalization remain important questions in animal evolution and comparative genetics. Ankfn1 genes are single copy in most invertebrates, partially duplicated in jawed vertebrates, and only the derived copy retained in most mammals. Null mutations in the single mouse homolog have vestibular and neurological abnormalities. Null mutation of the single Drosophila homolog is typically lethal with severe sensorimotor deficits in rare survivors. The functions and potential redundancy of paralogs in species with two copies are not known. Here, we define a vestibular role for Ankfn1 homologs in zebrafish based on the simultaneous disruption of each locus. Zebrafish with both paralogs disrupted showed vestibular defects and early lethality from swim bladder inflation failure. One intact copy at either locus was sufficient to prevent major phenotypes. Our results show that vertebrate Ankfn1 genes are required for vestibular-related functions, with at least partial redundancy between ancestral and derived paralogs.


Assuntos
Evolução Molecular , Peixe-Zebra , Animais , Duplicação Gênica , Camundongos , Organogênese , Penetrância , Filogenia , Peixe-Zebra/genética
12.
Clin J Sport Med ; 31(6): 516-521, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34446649

RESUMO

OBJECTIVE: The COVID-19 pandemic has affected all elements of global society, and sport is not exempt. Many sporting events have been either postponed or canceled, and national sporting organizations have had to make highly complex decisions in the face of scientific uncertainty and risk. This article applies these lessons to the world of sport with the goal of assisting sporting organizations to make sound and reasoned decisions during a pandemic. DATA SOURCES: A narrative approach using both academic literature sources and live examples from the authors' experience. We use Daniels and Sabin's accountability for reasonableness framework to facilitate decision-making in the face of such uncertainty. MAIN RESULTS: Decision-making in the context of uncertainty has the potential to create conflict and disengagement from key stakeholders. Evidence from recent pandemics has illustrated that an ethical approach to decision-making results in reasoned decision-making and confers a legitimacy to decisions that ultimately supports engagement and satisfaction from stakeholders. CONCLUSIONS: The incorporation of ethical considerations into risk assessment and management when making complex decisions, which incorporate high levels of uncertainty, will assist sporting organizations have positive outcomes.


Assuntos
COVID-19/psicologia , Tomada de Decisões , Pandemias/prevenção & controle , Esportes , COVID-19/epidemiologia , Humanos , SARS-CoV-2
13.
Front Sports Act Living ; 3: 601420, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681758

RESUMO

Health is a pre-requisite for optimal performance yet the parameters which govern health and performance of elite female athletes are little understood. The aim of this study was to quantify the health status of elite female athletes, and understand sociocultural factors influencing that status. The survey addressed demographic, health and athletic performance history, training load, contraceptive use, sport-specific appearance and performance pressures, and communication barriers. Three hundred and fifty-seven elite New Zealand female athletes were recruited to complete an on-line survey. Two hundred and nineteen athletes completed the survey. Oligomenorrhea/amenorrhea had been diagnosed in only 12% of athletes compared with 50% of athletes not on hormonal contraception who reported symptoms consistent with this diagnosis. Stress fractures and iron deficiency were common and associated with oligomenorrhoea/amenorrhea (P = 0.002), disordered eating (P = 0.009) or menorrhagia (P = 0.026). Athletes involved in individual sports (P = 0.047) and with higher training volumes (P < 0.001) were more likely to report a medical illness. Seventy-three percent of athletes felt pressured by their sport to alter their physical appearance to conform to gender ideals with 15% engaging in disordered eating practices. Barriers to communicating female health issues included male coaches and support staff, and lack of quality information pertaining to health. Elite female athletes may fail to reach peak performance due to specific health issues and undiagnosed pathology. Sociocultural factors influence the effectiveness of support of female's health and performance. Organizational and cultural change is required if elite female athletes are to combine optimal health with best performance.

14.
Stem Cell Res Ther ; 12(1): 93, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514411

RESUMO

BACKGROUND: Cell therapies present an exciting potential but there is a long history of expensive translational failures in stroke research. Researchers engaged in cell therapy research would benefit from a practical framework that can help in planning research and development of investigational cell therapies into viable medical products. METHODS: We developed a checklist using a mixed methodology approach to evaluate the impact of study design, regulatory policy, ethical, and health economic considerations for efficient implementation of early phase cell therapy studies. RESULTS: The checklist comprises a series of questions arranged under four domains: the first concerns study design such as characterization of target study population, trial design, endpoints and operational fit of dosage, time, and route of administration to target populations. A second domain addresses the data package required for regulatory approval relevant to the intended use (allogeneic/autologous; homologous/non-homologous; nature of cell processing). The third domain comprises patient involvement to ensure relevant data is collected via targeted study design. The final domain requires the team to determine the critical data elements that could be built into study design to enable health economic data collection to be started at an early phase of the study. CONCLUSIONS: The CT2S checklist can help to determine areas of expertise gaps and enable research groups to appropriately allocate resources for capacity building. Use of this checklist will allow identification of key areas where trial planning needs to be optimized, as well as helping to identify resources that need to be secured. The CT2S checklist can also serve as a general cell therapy research decision aid to improve research output and accelerate new cell therapy development.


Assuntos
Lista de Checagem , Acidente Vascular Cerebral , Terapia Baseada em Transplante de Células e Tecidos , Humanos , Projetos de Pesquisa , Acidente Vascular Cerebral/terapia
15.
Front Neurol ; 11: 589628, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33224099

RESUMO

Rationale: More than half of patients who receive thrombolysis for acute ischaemic stroke fail to recanalize. Elucidating biological factors which predict recanalization could identify therapeutic targets for increasing thrombolysis success. Hypothesis: We hypothesize that individual patient plasmin potential, as measured by in vitro response to recombinant tissue-type plasminogen activator (rt-PA), is a biomarker of rt-PA response, and that patients with greater plasmin response are more likely to recanalize early. Methods: This study will use historical samples from the Barcelona Stroke Thrombolysis Biobank, comprised of 350 pre-thrombolysis plasma samples from ischaemic stroke patients who received serial transcranial-Doppler (TCD) measurements before and after thrombolysis. The plasmin potential of each patient will be measured using the level of plasmin-antiplasmin complex (PAP) generated after in-vitro addition of rt-PA. Levels of antiplasmin, plasminogen, t-PA activity, and PAI-1 activity will also be determined. Association between plasmin potential variables and time to recanalization [assessed on serial TCD using the thrombolysis in brain ischemia (TIBI) score] will be assessed using Cox proportional hazards models, adjusted for potential confounders. Outcomes: The primary outcome will be time to recanalization detected by TCD (defined as TIBI ≥4). Secondary outcomes will be recanalization within 6-h and recanalization and/or haemorrhagic transformation at 24-h. This analysis will utilize an expanded cohort including ~120 patients from the Targeting Optimal Thrombolysis Outcomes (TOTO) study. Discussion: If association between proteolytic response to rt-PA and recanalization is confirmed, future clinical treatment may customize thrombolytic therapy to maximize outcomes and minimize adverse effects for individual patients.

16.
G3 (Bethesda) ; 10(11): 4241-4247, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32967895

RESUMO

Zfp423 encodes a transcriptional regulatory protein that interacts with canonical signaling and lineage pathways. Mutations in mouse Zfp423 or its human ortholog ZNF423 are associated with a range of developmental abnormalities reminiscent of ciliopathies, including cerebellar vermis hypoplasia and other midline brain defects. Null mice have reduced viability in most strain backgrounds. Here we show complete lethality on a C57BL/6J background, dominant rescue in backcrosses to any of 13 partner strains, with strain-dependent survival frequencies, and evidence for a BALB/c-derived survival modifier locus on chromosome 5. Survival data indicate both perinatal and postnatal periods of lethality. Anatomical data from a hypomorphic gene trap allele observed on both C57BL/6J and BALB/c congenic backgrounds shows an aggregate effect of background on sensitivity to Zfp423 loss rather than a binary effect on viability.


Assuntos
Genes Modificadores , Fatores de Transcrição , Alelos , Animais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fatores de Transcrição/genética
17.
PLoS Genet ; 16(9): e1009017, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32925911

RESUMO

Interpreting rare variants remains a challenge in personal genomics, especially for disorders with several causal genes and for genes that cause multiple disorders. ZNF423 encodes a transcriptional regulatory protein that intersects several developmental pathways. ZNF423 has been implicated in rare neurodevelopmental disorders, consistent with midline brain defects in Zfp423-mutant mice, but pathogenic potential of most patient variants remains uncertain. We engineered ~50 patient-derived and small deletion variants into the highly-conserved mouse ortholog and examined neuroanatomical measures for 791 littermate pairs. Three substitutions previously asserted pathogenic appeared benign, while a fourth was effectively null. Heterozygous premature termination codon (PTC) variants showed mild haploabnormality, consistent with loss-of-function intolerance inferred from human population data. In-frame deletions of specific zinc fingers showed mild to moderate abnormalities, as did low-expression variants. These results affirm the need for functional validation of rare variants in biological context and demonstrate cost-effective modeling of neuroanatomical abnormalities in mice.


Assuntos
Defeitos do Tubo Neural/genética , Proteínas/genética , Alelos , Animais , Encéfalo/patologia , Encefalopatias/genética , Modelos Animais de Doenças , Feminino , Frequência do Gene/genética , Genômica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Malformações do Sistema Nervoso/genética , Transtornos do Neurodesenvolvimento/genética , Proteínas/metabolismo , Fatores de Transcrição/genética , Dedos de Zinco
19.
Gen Dent ; 68(3): 51-56, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348244

RESUMO

Low-viscosity polymer resins, or surface sealants (SSs), have been utilized as a means of finalizing the polishing step following the placement of composite resin restorations. The aim of this study was to measure the surface roughness (Ra) of composite resins treated with different SSs before and after exposure to an accelerated artificial aging protocol. The study included 5 experimental groups of composite resin discs (TPH Spectra ST) treated with different SSs (PermaSeal, Embrace WetBond Seal-n-Shine, OptiGuard, BisCover LV, and DuraFinish) and a control group consisting of untreated discs (n = 6 per group). The discs were prepared by inserting composite resin in 10 × 1-mm rings, covering the ring and material with a transparent strip, compressing the assembly between glass slides, and polymerizing through the slides on each side for 40 seconds with an LED curing light. Each disc except for the control specimens received a coating of the selected SS followed by application of a transparent matrix strip and then light polymerization for 20 seconds using an LED light source. Surface roughness measurements were obtained with a digital contact profilometer at baseline (immediately after polymerization) and following exposure to a thermocycling regimen to simulate aging. The data were analyzed using 2-way analysis of variance and post hoc Student-Newman-Keuls test with significance set at P < 0.05. There were no statistically significant differences among the groups at baseline. There were no statistically significant differences between the baseline and post-thermocycling Ra measurements except among the DuraFinish specimens, which were significantly rougher than all other groups after accelerated artificial aging. The use of SSs for the initial insertion and possibly for the long-term maintenance of composite resins could be minimally beneficial for restoration maintenance if a transparent covering medium is utilized during polymerization. However, due to the effects caused by formation of an oxygen-inhibited layer of unpolymerized monomers if a covering medium is not used, the results suggest the benefits do not offset the costs considering both gloss and Ra surface-testing parameters.


Assuntos
Resinas Compostas , Polimento Dentário , Humanos , Teste de Materiais , Propriedades de Superfície
20.
BMJ Open ; 10(4): e038180, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32265253

RESUMO

INTRODUCTION: Intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator (rt-PA) is the only approved pharmacological reperfusion therapy for acute ischaemic stroke. Despite population benefit, IVT is not equally effective in all patients, nor is it without significant risk. Uncertain treatment outcome prediction complicates patient treatment selection. This study will develop and validate predictive algorithms for IVT response, using clinical, radiological and blood-based biomarker measures. A secondary objective is to develop predictive algorithms for endovascular thrombectomy (EVT), which has been proven as an effective reperfusion therapy since study inception. METHODS AND ANALYSIS: The Targeting Optimal Thrombolysis Outcomes Study is a multicenter prospective cohort study of ischaemic stroke patients treated at participating Australian Stroke Centres with IVT and/or EVT. Patients undergo neuroimaging using multimodal CT or MRI at baseline with repeat neuroimaging 24 hours post-treatment. Baseline and follow-up blood samples are provided for research use. The primary outcome is good functional outcome at 90 days poststroke, defined as a modified Rankin Scale (mRS) Score of 0-2. Secondary outcomes are reperfusion, recanalisation, infarct core growth, change in stroke severity, poor functional outcome, excellent functional outcome and ordinal mRS at 90 days. Primary predictive models will be developed and validated in patients treated only with rt-PA. Models will be built using regression methods and include clinical variables, radiological measures from multimodal neuroimaging and blood-based biomarkers measured by mass spectrometry. Predictive accuracy will be quantified using c-statistics and R2. In secondary analyses, models will be developed in patients treated using EVT, with or without prior IVT, reflecting practice changes since original study design. ETHICS AND DISSEMINATION: Patients, or relatives when patients could not consent, provide written informed consent to participate. This study received approval from the Hunter New England Local Health District Human Research Ethics Committee (reference 14/10/15/4.02). Findings will be disseminated via peer-reviewed publications and conference presentations.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Adolescente , Adulto , Idoso , Austrália , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Humanos , New England , Estudos Prospectivos , Reperfusão , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Trombectomia , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
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