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2.
Eur J Obstet Gynecol Reprod Biol ; 297: 132-137, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38626514

RESUMO

OBJECTIVES: Numerous animal and epidemiologic studies have demonstrated a positive association between maternal obesity in pregnancy and obesity in offspring. The biologic mechanisms of this association remain under investigation. One proposed mechanism includes fetoplacental endothelial dysfunction secondary to inflammation. Endocan is a relatively new biomarker for endothelial dysfunction and inflammation. Our objectives were to examine (1) the association between maternal obesity and neonatal serum endocan at birth, and (2) the association between neonatal serum endocan at birth and pediatric obesity at 24-36 months of age. STUDY DESIGN: This was a secondary analysis of a prospective cohort of neonates born < 33 weeks gestation. Serum endocan was collected within 48 hours of birth. Serum endocan levels were compared in neonates born to obese mothers vs. those born to non-obese mothers. BMI data were retrospectively collected from cohort neonates between 24 and 36 months of age. RESULTS: The analysis included 120 mother/neonate dyads. Neonates born to obese mothers had higher median serum endocan at birth compared to neonates born to non-obese mothers (299 ng/L [205-586] vs. 251 ng/L [164-339], p = 0.045). In a linear regression modeled on neonatal serum endocan level, maternal obesity had a statistically significant positive association (p = 0.021). Higher mean serum endocan level at birth was associated with pediatric obesity between 24 and 36 months (obese vs. non-obese offspring; 574 ng/L (222) vs. 321 ng/L (166), p = 0.005). CONCLUSIONS: In our cohort of preterm neonates, elevated serum endocan at birth was associated with both maternal obesity and downstream pediatric obesity. More research is needed to understand intergenerational transmission of obesity. A large focus has been on epigenetic modification. Endothelial dysfunction and inflammation may play important roles in these pathways. Effective biomarkers, including endocan, may also serve as intermediate outcomes in future pregnancy research.


Assuntos
Biomarcadores , Recém-Nascido Prematuro , Inflamação , Proteínas de Neoplasias , Obesidade Materna , Obesidade Infantil , Proteoglicanas , Humanos , Feminino , Proteoglicanas/sangue , Recém-Nascido , Biomarcadores/sangue , Gravidez , Obesidade Infantil/sangue , Obesidade Infantil/complicações , Obesidade Infantil/fisiopatologia , Recém-Nascido Prematuro/sangue , Proteínas de Neoplasias/sangue , Adulto , Obesidade Materna/sangue , Masculino , Inflamação/sangue , Estudos Prospectivos , Pré-Escolar , Endotélio Vascular/fisiopatologia
5.
Public Health ; 225: 343-352, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37979311

RESUMO

INTRODUCTION: The COVID-19 pandemic has prompted governments internationally to consider strengthening their public health systems. To support the work of Ireland's Public Health Reform Expert Advisory Group, the Health Information and Quality Authority, an independent governmental agency, was asked to describe the lessons learnt regarding the public health response to COVID-19 internationally and the applicability of this response for future pandemic preparedness. METHODS: Semi-structured interviews with key public health representatives from nine countries were conducted. Interviews were conducted in March and April 2022 remotely via Zoom and were recorded. Notes were taken by two researchers, and a thematic analysis undertaken. RESULTS: Lessons learnt from the COVID-19 pandemic related to three main themes: 1) setting policy; 2) delivering public health interventions; and 3) providing effective communication. Real-time surveillance, evidence synthesis, and cross-sectoral collaboration were reported as essential for policy setting; it was noted that having these functions established prior to the pandemic would lead to a more efficient implementation in a health emergency. Delivering public health interventions such as testing, contact tracing, and vaccination were key to limiting and or mitigating the spread of the SARS-CoV-2 virus. However, a number of challenges were highlighted such as staff capacity and burnout, delays in vaccination procurement, and reduced delivery of regular healthcare services. Clear, consistent, and regular communication of the scientific evidence was key to engaging citizens with mitigation strategies. However, these communication strategies had to compete with an infodemic of information being circulated, particularly through social media. CONCLUSIONS: Overall, functions relating to policy setting, public health interventions, and communication are key to pandemic response. Ideally, these should be established in the preparedness phase so that they can be rapidly scaled-up during a pandemic.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Pandemias/prevenção & controle , Reforma dos Serviços de Saúde , Saúde Pública
6.
Occup Med (Lond) ; 73(6): 332-338, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37542726

RESUMO

BACKGROUND: Women over 50 years are one of the fastest-growing employment groups. Menopausal symptoms can adversely impact quality of life, work performance and attendance; however, few studies look at the impact of individual menopausal symptoms on work and career development. AIMS: To measure the prevalence of menopausal symptoms in employees in a healthcare setting, to assess the impact of individual symptoms on work, attendance and career development and to explore perceptions about workplace supports. METHODS: In this cross-sectional study of Irish hospital workers, menopausal employees were asked about the frequency of 10 menopausal symptoms and the extent to which each symptom impacted them at work. Impacts on performance, attendance and career development were assessed, along with the benefits of workplace support. RESULTS: Responses from 407 women showed that the most common menopausal symptoms affecting employees greater than 50% of the time while at work were fatigue (54%), difficulty sleeping (47%), poor concentration (44%) and poor memory (40%). Work performance was impacted for 65% of respondents and 18% had taken sick leave. There was a significant association between symptom severity at work and reduced work performance, career development decisions and attendance. Manager awareness about menopause (29%) and flexible working times (29%) were selected as the most important workplace supports. CONCLUSIONS: Female employees are negatively impacted by menopausal symptoms while at work, particularly by psychological and neurocognitive symptoms which were associated with reduced work performance, attendance and career decisions. Manager awareness and flexible schedules were considered the most beneficial workplace supports.


Assuntos
Emprego , Qualidade de Vida , Humanos , Feminino , Estudos Transversais , Emprego/psicologia , Local de Trabalho/psicologia , Menopausa/psicologia , Inquéritos e Questionários
7.
S Afr Med J ; 113(2): 57-60, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36757073

RESUMO

The illegal practice of combining organophosphates (OPs) with other compounds such as carbamates and pyrethroids, creating 'streetpesticides', is common in South Africa. These agents contain mostly unknown quantities of unregulated toxins and contribute to atypicaland unpredictable clinical presentations following human ingestion. We present such a case in a patient with intentional rodenticideingestion. The initial presentation in the emergency department was a classic cholinergic toxidrome, and clinical resolution was achievedafter provision of atropine. This was followed 12 hours later by an acute decompensation resulting from an apparent sympatheticallydriven episode of autonomic instability and acute pulmonary oedema requiring immediate respiratory and haemodynamic support. In ourdiscussion, we explore this secondary decompensation and suggest various pathophysiological explanations for this atypical clinical coursefollowing what had appeared to be OP poisoning. The patient was discharged home after a total of 6 days in hospital.


Assuntos
Atropina , Piretrinas , Humanos , África do Sul , Atropina/uso terapêutico , Carbamatos , Organofosfatos
8.
BMC Emerg Med ; 21(1): 15, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33509099

RESUMO

BACKGROUND: Early warning systems (EWSs) are used to assist clinical judgment in the detection of acute deterioration to avoid or reduce adverse events including unanticipated cardiopulmonary arrest, admission to the intensive care unit and death. Sometimes healthcare professionals (HCPs) do not trigger the alarm and escalate for help according to the EWS protocol and it is unclear why this is the case. The aim of this qualitative evidence synthesis was to answer the question 'why do HCPs fail to escalate care according to EWS protocols?' The findings will inform the update of the National Clinical Effectiveness Committee (NCEC) National Clinical Guideline No. 1 Irish National Early Warning System (INEWS). METHODS: A systematic search of the published and grey literature was conducted (until February 2018). Data extraction and quality appraisal were conducted by two reviewers independently using standardised data extraction forms and quality appraisal tools. A thematic synthesis was conducted by two reviewers of the qualitative studies included and categorised into the barriers and facilitators of escalation. GRADE CERQual was used to assess the certainty of the evidence. RESULTS: Eighteen studies incorporating a variety of HCPs across seven countries were included. The barriers and facilitators to the escalation of care according to EWS protocols were developed into five overarching themes: Governance, Rapid Response Team (RRT) Response, Professional Boundaries, Clinical Experience, and EWS parameters. Barriers to escalation included: Lack of Standardisation, Resources, Lack of accountability, RRT behaviours, Fear, Hierarchy, Increased Conflict, Over confidence, Lack of confidence, and Patient variability. Facilitators included: Accountability, Standardisation, Resources, RRT behaviours, Expertise, Additional support, License to escalate, Bridge across boundaries, Clinical confidence, empowerment, Clinical judgment, and a tool for detecting deterioration. These are all individual yet inter-related barriers and facilitators to escalation. CONCLUSIONS: The findings of this qualitative evidence synthesis provide insight into the real world experience of HCPs when using EWSs. This in turn has the potential to inform policy-makers and HCPs as well as hospital management about emergency response system-related issues in practice and the changes needed to address barriers and facilitators and improve patient safety and quality of care.


Assuntos
Pessoal de Saúde , Equipe de Respostas Rápidas de Hospitais , Atenção à Saúde , Hospitalização , Humanos , Pesquisa Qualitativa
9.
Ir Med J ; 114(5): 354, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35015953

RESUMO

Aim This study evaluated the use of Lumbar Puncture (LP) in a general paediatric unit over a 3-year period. Methods Index patients, who had a successful LP, were identified from the microbiology database and failed LP procedures were identified from a chart review of the serum PCR database. Data abstracted included 1) patient age, 2) LP indication, 3) LP procedure outcome; classified as atraumatic, traumatic or failed, 4) grade of doctor undertaking the procedure and 5) the final diagnosis. Results We identified 104 paediatric patients, of whom 29(27.9%) were neonates. LP was indicated for the evaluation of acute undifferentiated illnesses, with 33 (31.7%) patients having fever without source beyond the neonatal period and 16 (15.4%) being neonates with fever. A CSF sample was obtained in 96 (92.4%) patients, with 71 (73.9%) being atraumatic. Successful LP was undertaken by Consultants in 4 (4.1%), Registrars in 83 (86.5%) and SHOs in 9 (9.4%) patients. 14 (14.6%) patients had positive CSF cultures with an additional 23 having positive cultures or serology (9 blood cultures, 11 urine cultures and 3 positive serum PCR). Conclusion Skill in LP performance is still required, to evaluate acute undifferentiated illness, in general paediatric units and ancillary methods to aid SHOs with LP skill development is desirable.


Assuntos
Febre , Punção Espinal , Criança , Pré-Escolar , Humanos , Recém-Nascido
11.
J Neurosurg Sci ; 64(5): 427-433, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29480680

RESUMO

BACKGROUND: Adjacent-level disease after anterior cervical discectomy and fusion (ACDF) occurs in a significant proportion of patients and frequently requires revision operation. Methods using traditional plates typically require removal of the plate with anecdotally increased operative-time and morbidity. We review our experience in treating symptomatic adjacent-segment disease using both traditional plate removal and modular-plate system which allows for add-on plate components rather than removal of the entire plate. METHODS: Authors compared 64 patients with revision surgery using modular-plate system for adjacent-segment disease compared to 2-cohorts: 1) patients with traditional plate-removal; and 2) patients with no prior plate. Clinical data included demographics, original surgery, presentation, current surgery, use of modular system, need for preoperative computed-topography, operative-time, blood loss, hospital stay, complications, length of dysphagia, neck disability index and time-until-fusion. RESULTS: Modular cervical plate system was utilized to prevent exposure and removal of the entire plate. The terminal portion of the plate was exposed and the distal module was removed. Following the discectomy/arthrodesis, a module-plate extension was added onto the previous plate for extension of the prior instrumentation. Preoperative planning computed-topography was required in 26% of plate-removal and 17% of modular-plate cases. Revision surgery with no prior plate had reduced operative-time (77.0±18.1 min) when compared with plate removal (103.8±46.2 min; P<0.01). Blood-loss was lower for modular-plate system (38.3±20.4 mL) and no prior plate (38.4±12.6 mL) versus plate removal (78.2±65.9 mL, P<0.01). Hospital stay was similar for all groups. No complications were experienced with modular-plate revision but plate removal and revision after no prior plate carried 7.7% and 10.5% complication rates, respectively. There was a trend towards lower dysphagia and neck disability index with modular-plate revision. CONCLUSIONS: Use of modular cervical plate system allows for extension of a plate and reduces morbidity when treating adjacent-segment disease.


Assuntos
Vértebras Cervicais , Fusão Vertebral , Placas Ósseas , Vértebras Cervicais/cirurgia , Discotomia , Humanos , Resultado do Tratamento
12.
Spine (Phila Pa 1976) ; 44(23): 1676-1684, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31730573

RESUMO

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To evaluate the performance and convergent validity of the disabilities of the arm, shoulder, and hand (DASH) in comparison with the visual analog scale (VAS) for pain, and neck disability index (NDI) in patients undergoing cervical spine surgery. SUMMARY OF BACKGROUND DATA: Neck-specific disability scales do not adequately assess concurrent upper extremity involvement in patients with cervical spine disorders. The DASH is a patient-reported outcomes (PRO) instrument designed to measure functional disability due to upper extremity conditions but has additionally been shown to perform well in patients with neck disorders. METHODS: We identified patients who underwent cervical spine surgery at our institution between 2013 and 2016. We collected demographic information, clinical characteristics, and PRO measures-DASH, VAS, NDI-preoperatively, as well as early and late postoperatively. We calculated descriptive statistics and changes from baseline in PROs. Correlation coefficients were used to quantify the association between PRO measures. The analysis was stratified by radiculopathy and myelopathy diagnoses. RESULTS: A total of 1046 patients (52.8% male) with PROs data at baseline were included in the analysis. The mean age at surgery ±â€ŠSD was 57.2 ±â€Š11.3 years, and postoperative follow-up duration 12.7 ±â€Š10.7 months. The most common surgical procedure was anterior cervical discectomy and fusion (71.1%). Patients experienced clinically meaningful postoperative improvements in all PRO measures. The DASH showed moderate positive correlations with VAS preoperatively (Spearman rho = 0.43), as well as early (rho = 0.48) and late postoperatively (rho = 0.60). DASH and NDI scores were strongly positively correlated across operative states (Preoperative rho = 0.74, Early Postoperative rho = 0.78, Late Postoperative rho = 0.82). Stratified analysis by preoperative diagnosis showed similar within-groups trends and pairwise correlations. However, radiculopathy patients experienced larger magnitude early and late change scores. CONCLUSION: The DASH is a valid and responsive PRO measure to evaluate disabling upper extremity involvement in patients undergoing cervical spine surgery. LEVEL OF EVIDENCE: 3.


Assuntos
Vértebras Cervicais/cirurgia , Avaliação da Deficiência , Medidas de Resultados Relatados pelo Paciente , Doenças da Coluna Vertebral/cirurgia , Adulto , Idoso , Braço/patologia , Feminino , Mãos/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/normas , Reprodutibilidade dos Testes , Estudos Retrospectivos , Ombro/patologia , Doenças da Coluna Vertebral/diagnóstico , Resultado do Tratamento
13.
J R Coll Physicians Edinb ; 48(4): 338-340, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30488892

RESUMO

BACKGROUND: In a recent paper a working group set up by the Lay Advisory Committee of the Royal College of Physicians of Edinburgh (RCPE) had looked into the problems of patients with severe communication difficulties in hospital (J R Coll Physicians Edinb 2017; 47: 211-3). The present online survey expands on this with the objective of garnering the views of physicians on this matter. METHOD: An invitation aimed at physicians to complete an online survey was made through the recently published paper. The survey was open between September and December 2017. RESULTS: There were 83 completed surveys. A total of 69 of the returns were UK based, with the remainder from Asia, Australia, Africa and non-UK Europe and one unidentified location. The majority (44) were consultants, the remainder included those in core medical training, general practice and psychology. A wide range of medical departments were represented in the returns, with the largest returns coming from care of the elderly and acute medical departments. Four key themes were highlighted by responders: time, training, resources and environment. CONCLUSION: Based on these results, the working group have embarked upon the next phase of the project with three main tasks: firstly, to work with the RCPE to disseminate the survey findings to a wider audience; secondly, to collate the detailed suggestions for improvement to be used alongside the survey findings and any subsequent documentation or advice; thirdly, to formulate with the RCPE a strategy to promote good practice in hospitals related to the experiences of patients with severe communication difficulties.


Assuntos
Barreiras de Comunicação , Transtornos da Comunicação/complicações , Comunicação , Relações Médico-Paciente , Médicos , Atitude do Pessoal de Saúde , Hospitais , Humanos , Inquéritos e Questionários , Fatores de Tempo
14.
J R Soc Interface ; 15(145)2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30158181

RESUMO

Limpets and other molluscs rely on shells to protect them from physical damage, predation, dehydration, etc. If the shell becomes damaged, this may significantly impair its function. In this work, experiments were carried out to investigate the effect of damage on the strength of shells of the common limpet (Patella vulgata) and their ability to repair this damage effectively. Shells were damaged in three ways: (i) low-energy impacts; (ii) abrasion of the outer layer; and (iii) creation of a small hole in the apex of the shell. Shells were left to repair for several time periods (0, 10, 30 and 60 days). The mechanical strength was evaluated by impacting the shells with a weight dropped from a known height. The damage reduced the strength (defined as impact energy to failure) by 50-70% depending on damage type. After 60 days, limpets in all three groups had repaired their shells significantly, bringing their strength to 79-91% of the control value (in each case, samples were statistically indistinguishable from their control counterparts). Measurements of the thickness of the shell at the apex suggest that the main effect of low-energy impact and abrasion is reduction in thickness, which correlates linearly with the impact energy needed for failure. The method of repair is believed to be by the growth of fresh shell material on the inside of the shell, though we could not identify this new material specifically. Even after 60 days, the shells were still statistically thinner than the controls. Consequently, there may be some other strengthening mechanism at work. This work has demonstrated the remarkable ability of limpets to detect the mechanical weakening of their shells caused by relatively subtle forms of damage and to take appropriate action to restore shell strength.


Assuntos
Exoesqueleto , Gastrópodes , Regeneração/fisiologia , Estresse Mecânico , Exoesqueleto/anatomia & histologia , Exoesqueleto/fisiologia , Animais , Gastrópodes/anatomia & histologia , Gastrópodes/fisiologia , Fatores de Tempo
15.
Nature ; 555(7695): 216-219, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29516997

RESUMO

The familiar axisymmetric zones and belts that characterize Jupiter's weather system at lower latitudes give way to pervasive cyclonic activity at higher latitudes. Two-dimensional turbulence in combination with the Coriolis ß-effect (that is, the large meridionally varying Coriolis force on the giant planets of the Solar System) produces alternating zonal flows. The zonal flows weaken with rising latitude so that a transition between equatorial jets and polar turbulence on Jupiter can occur. Simulations with shallow-water models of giant planets support this transition by producing both alternating flows near the equator and circumpolar cyclones near the poles. Jovian polar regions are not visible from Earth owing to Jupiter's low axial tilt, and were poorly characterized by previous missions because the trajectories of these missions did not venture far from Jupiter's equatorial plane. Here we report that visible and infrared images obtained from above each pole by the Juno spacecraft during its first five orbits reveal persistent polygonal patterns of large cyclones. In the north, eight circumpolar cyclones are observed about a single polar cyclone; in the south, one polar cyclone is encircled by five circumpolar cyclones. Cyclonic circulation is established via time-lapse imagery obtained over intervals ranging from 20 minutes to 4 hours. Although migration of cyclones towards the pole might be expected as a consequence of the Coriolis ß-effect, by which cyclonic vortices naturally drift towards the rotational pole, the configuration of the cyclones is without precedent on other planets (including Saturn's polar hexagonal features). The manner in which the cyclones persist without merging and the process by which they evolve to their current configuration are unknown.

16.
J Neurosurg Sci ; 62(4): 406-412, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27149369

RESUMO

BACKGROUND: A number of clinical tools exist for measuring the severity of cervical spondylotic myelopathy (CSM). Several studies have recently described the use of non-invasive imaging biomarkers to assess severity of disease. These imaging markers may provide an additional tool to measure disease progression and represent a surrogate marker of response to therapy. Correlating these imaging biomarkers with clinical quantitative measures is critical for accurate therapeutic stratification and quantification of axonal injury. METHODS: Fourteen patients and seven healthy control subjects were enrolled. Patients were classified as mildly (7) or moderately (7) impaired based on Modified Japanese Orthopedic Association Scale. All patients underwent diffusion tensor imaging (DTI) and diffusion basis spectrum imaging (DBSI) analyses. In addition to standard neurological examination, all participants underwent 30-m Walking Test, 9-hole Peg Test (9HPT), grip strength, key pinch, and vibration sensation thresholds in the index finger and great toe. Differences in assessment scores between controls, mild and moderate CSM patients were correlated with DTI and DBSI derived fractional anisotropy (FA). RESULTS: Clinically, 30-meter walking times were significantly longer in the moderately impaired group than in the control group. Maximum 9HPT times were significantly longer in both the mildly and moderately impaired groups as compared to normal controls. Scores on great toe vibration sensation thresholds were lower in the mildly impaired and moderately impaired groups as compared to controls. We found no clear evidence for any differences in minimum grip strength, minimum key pinch, or index finger vibration sensation thresholds. There were moderately strong associations between DTI and DBSI FA values and 30-meter walking times and 9HPT. CONCLUSIONS: The 30-m Walking Test and 9HPT were both moderately to strongly associated with DTI/DBSI FA values. FA may represent an additional measure to help differentiate and stratify patients with mild or moderate CSM.


Assuntos
Anisotropia , Neuroimagem/métodos , Doenças da Medula Espinal/diagnóstico por imagem , Adulto , Vértebras Cervicais , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/etiologia , Doenças da Medula Espinal/etiologia , Espondilose/complicações
19.
Ir Med J ; 110(6): 581, 2017 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-28952671

RESUMO

This study was undertaken to evaluate uncertainty from the Basic Specialist Trainee perspective. The survey of trainees explored 1) factors in decision making, 2) the personal impact of uncertainty, 3) the responses to both clinical errors and challenges to their decision making and 4) the potential strategies to address uncertainty. Forty-one (93%) of trainees surveyed responded. Important factors in decision making were clinical knowledge and senior colleague's opinion. Sixty percent experienced significant anxiety post call as a consequence of their uncertainty. When errors are made by colleagues, the trainee's response is acceptance (52.5%), and sympathy (32%).Trainees are strongly influenced by the opinions of senior colleagues often changing their opinions having made confident decisions. Solutions to address uncertainty include enhanced knowledge translation, and to a lesser extent, enhanced personal awareness and resilience awareness. To enhance the training experience for BST and lessen the uncertainty experienced these strategies need to be enacted within the training milieu.


Assuntos
Ansiedade/etiologia , Tomada de Decisão Clínica , Erros Médicos/psicologia , Pediatria/economia , Incerteza , Conscientização , Criança , Competência Clínica , Pesquisas sobre Atenção à Saúde , Humanos , Pediatras/psicologia , Resiliência Psicológica , Especialização
20.
Neuroimage ; 159: 334-345, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28797738

RESUMO

Alzheimer's disease is connected to a number of other neurodegenerative conditions, known collectively as 'tauopathies', by the presence of aggregated tau protein in the brain. Neuroinflammation and oxidative stress in AD are associated with tau pathology and both the breakdown of axonal sheaths in white matter tracts and excess iron accumulation grey matter brain regions. Despite the identification of myelin and iron concentration as major sources of contrast in quantitative susceptibility maps of the brain, the sensitivity of this technique to tau pathology has yet to be explored. In this study, we perform Quantitative Susceptibility Mapping (QSM) and T2* mapping in the rTg4510, a mouse model of tauopathy, both in vivo and ex vivo. Significant correlations were observed between histological measures of myelin content and both mean regional magnetic susceptibility and T2* values. These results suggest that magnetic susceptibility is sensitive to tissue myelin concentrations across different regions of the brain. Differences in magnetic susceptibility were detected in the corpus callosum, striatum, hippocampus and thalamus of the rTg4510 mice relative to wild type controls. The concentration of neurofibrillary tangles was found to be low to intermediate in these brain regions indicating that QSM may be a useful biomarker for early stage detection of tau pathology in neurodegenerative diseases.


Assuntos
Doença de Alzheimer/patologia , Mapeamento Encefálico/métodos , Encéfalo/patologia , Tauopatias/patologia , Animais , Feminino , Processamento de Imagem Assistida por Computador , Camundongos , Camundongos Transgênicos , Emaranhados Neurofibrilares/patologia
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