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Working memory (WM) enables the temporary storage of limited information and is a central component of higher order cognitive function. Irrelevant and/or distracting information can have a negative impact on WM processing and suppressing such incoming stimuli is critical to maintaining adequate performance. However, the neural mechanisms and dynamics underlying such distractor inhibition remain poorly understood. In the current study, we enrolled 46 healthy adults (Mage: 27.92, Nfemale: 28) who completed a Sternberg type WM task with high- and low-distractor conditions during magnetoencephalography (MEG). MEG data were transformed into the time-frequency domain and significant task-related oscillatory responses were imaged to identify the underlying anatomical areas. Whole-brain paired t-tests, with cluster-based permutation testing for multiple comparisons correction, were performed to assess differences between the low- and high-distractor conditions for each oscillatory response. Across conditions, we found strong alpha and beta oscillations (i.e., decreases relative to baseline) and increases in theta power throughout the encoding and maintenance periods. Whole-brain contrasts revealed significantly stronger alpha and beta oscillations in bilateral prefrontal regions during maintenance in high- compared to low-distractor trials, with the stronger beta oscillations being centered on the left dorsolateral prefrontal cortex and right inferior frontal gyrus, while those for alpha being within the right anterior prefrontal cortices and the right middle frontal gyrus. These findings suggest that alpha and beta oscillations in the bilateral prefrontal cortices play a major role in the inhibition of distracting information during WM maintenance. Our results also contribute to prior research on cognitive control and functional inhibition, in which prefrontal regions have been widely implicated.
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Atención , Magnetoencefalografía , Memoria a Corto Plazo , Corteza Prefrontal , Humanos , Corteza Prefrontal/fisiología , Memoria a Corto Plazo/fisiología , Adulto , Masculino , Magnetoencefalografía/métodos , Femenino , Adulto Joven , Atención/fisiologíaRESUMEN
RATIONALE: Ansa cervicalis stimulation (ACS) of the infrahyoid muscles has been proposed as a neurostimulation therapy for obstructive sleep apnea (OSA). ACS stabilizes the pharynx by pulling it caudally, but its specific effects on flow limitation caused by palatal, oropharyngeal lateral wall, tongue base, or epiglottis collapse remains unclear. OBJECTIVES: To quantify the effect of ACS on collapsibility of different pharyngeal flow-limiting structures. METHODS: Participants with OSA underwent bilateral ACS during drug-induced sleep endoscopy. Maximum inspiratory airflow was assessed over a range of positive airway pressures while ACS was applied. The flow-limiting structure for each breath was classified based on manometric and endoscopic findings and a linear mixed-effects model characterized their response to ACS. The influence of patient characteristics was explored with univariate models. MEASUREMENTS AND MAIN RESULTS: Forty-one participants yielded 1761 breaths for analysis. On average, bilateral ACS decreased the observed pharyngeal critical closing (PCRIT) and opening (POPEN) pressures by -3.0 [95% confidence interval: [-3.6, -2.3] and -3.7 [-4.4, -3.0] cmH2O, respectively (p<0.001). During tongue base obstruction, modeled ACS effects for PCRIT and POPEN were -2.0 [-2.7, -1.4] and -3.1 [-3.8, -2.4] cmH2O, respectively (p<0.001). Greater reductions were generally observed for other flow-limiting structures. A lower apnea-hypopnea index was associated with a greater decrease in POPEN (p<0.01). Other patient characteristics, including body mass index, did not influence PCRIT or POPEN (p>0.05). CONCLUSIONS: Bilateral ACS decreased collapsibility of all airway flow-limiting structures. ACS generally had greater effects on palatal, oropharyngeal lateral wall, and epiglottic collapse than the tongue base.
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PURPOSE: Widening the availability of fetal MRI with fully automatic real-time planning of radiological brain planes on 0.55T MRI. METHODS: Deep learning-based detection of key brain landmarks on a whole-uterus echo planar imaging scan enables the subsequent fully automatic planning of the radiological single-shot Turbo Spin Echo acquisitions. The landmark detection pipeline was trained on over 120 datasets from varying field strength, echo times, and resolutions and quantitatively evaluated. The entire automatic planning solution was tested prospectively in nine fetal subjects between 20 and 37 weeks. A comprehensive evaluation of all steps, the distance between manual and automatic landmarks, the planning quality, and the resulting image quality was conducted. RESULTS: Prospective automatic planning was performed in real-time without latency in all subjects. The landmark detection accuracy was 4.2 ± $$ \pm $$ 2.6 mm for the fetal eyes and 6.5 ± $$ \pm $$ 3.2 for the cerebellum, planning quality was 2.4/3 (compared to 2.6/3 for manual planning) and diagnostic image quality was 2.2 compared to 2.1 for manual planning. CONCLUSIONS: Real-time automatic planning of all three key fetal brain planes was successfully achieved and will pave the way toward simplifying the acquisition of fetal MRI thereby widening the availability of this modality in nonspecialist centers.
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Encéfalo , Feto , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Humanos , Encéfalo/diagnóstico por imagen , Encéfalo/embriología , Imagen por Resonancia Magnética/métodos , Femenino , Embarazo , Feto/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Aprendizaje Profundo , Diagnóstico Prenatal/métodos , Estudios Prospectivos , Imagen Eco-Planar/métodos , Algoritmos , Interpretación de Imagen Asistida por Computador/métodosRESUMEN
OBJECTIVE: To utilise combined diffusion-relaxation MRI techniques to interrogate antenatal changes in the placenta prior to extreme preterm birth among both women with PPROM and membranes intact, and compare this to a control group who subsequently delivered at term. DESIGN: Observational study. SETTING: Tertiary Obstetric Unit, London, UK. POPULATION: Cases: pregnant women who subsequently spontaneously delivered a singleton pregnancy prior to 32 weeks' gestation without any other obstetric complications. CONTROLS: pregnant women who delivered an uncomplicated pregnancy at term. METHODS: All women consented to an MRI examination. A combined diffusion-relaxation MRI of the placenta was undertaken and analysed using fractional anisotropy, a combined T2*-apparent diffusion coefficient model and a combined T2*-intravoxel incoherent motion model, in order to provide a detailed placental phenotype associated with preterm birth. Subgroup analyses based on whether women in the case group had PPROM or intact membranes at time of scan, and on latency to delivery were performed. MAIN OUTCOME MEASURES: Fractional anisotropy, apparent diffusion coefficients and T2* placental values, from two models including a combined T2*-IVIM model separating fast- and slow-flowing (perfusing and diffusing) compartments. RESULTS: This study included 23 women who delivered preterm and 52 women who delivered at term. Placental T2* was lower in the T2*-apparent diffusion coefficient model (p < 0.001) and in the fast- and slow-flowing compartments (p = 0.001 and p < 0.001) of the T2*-IVIM model. This reached a higher level of significance in the preterm prelabour rupture of the membranes group than in the membranes intact group. There was a reduced perfusion fraction among the cases with impending delivery. CONCLUSIONS: Placental diffusion-relaxation reveals significant changes in the placenta prior to preterm birth with greater effect noted in cases of preterm prelabour rupture of the membranes. Application of this technique may allow clinically valuable interrogation of histopathological changes before preterm birth. In turn, this could facilitate more accurate antenatal prediction of preterm chorioamnionitis and so aid decisions around the safest time of delivery. Furthermore, this technique provides a research tool to improve understanding of the pathological mechanisms associated with preterm birth in vivo.
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OBJECTIVES: To evaluate changes occurring in the fetal brain prior to very preterm delivery using MRI T2* relaxometry, an indirect assessment of tissue perfusion. METHOD: Fetuses that subsequently delivered spontaneously <32 weeks gestation and a control cohort were identified from pre-existing datasets. Participants had undergone a 3T MRI assessment including T2* relaxometry of the fetal brain using a 2D multi-slice gradient echo single shot echo planar imaging sequence. T2* maps were generated, supratentorial brain tissue was manually segmented and mean T2* values were generated. Groups were compared using quadratic regression. RESULTS: Twenty five fetuses that subsequently delivered <32 weeks and 67 that delivered at term were included. Mean gestation at MRI was 24.5 weeks (SD 3.3) and 25.4 weeks (SD 3.1) and gestation at delivery 25.5 weeks (SD 3.4) and 39.7 weeks (SD 1.2) in the preterm and term cohorts respectively. Brain mean T2* values were significantly lower in fetuses that subsequently delivered before 32 weeks gestation (p < 0.001). CONCLUSION: Alterations in brain maturation appear to occur prior to preterm delivery. Further work is required to explore these associations, but these findings suggest a potential window for therapeutic neuroprotective agents in fetuses at high risk of preterm delivery in the future.
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Nacimiento Prematuro , Recién Nacido , Femenino , Humanos , Nacimiento Prematuro/diagnóstico por imagen , Proyectos Piloto , Recien Nacido Extremadamente Prematuro , Imagen por Resonancia Magnética/métodos , Feto , EncéfaloRESUMEN
INTRODUCTION: Spontaneous preterm birth prior to 32 weeks' gestation accounts for 1% of all deliveries and is associated with high rates of morbidity and mortality. A total of 70% are associated with chorioamnionitis which increases the incidence of morbidity, but for which there is no noninvasive antenatal test. Fetal adrenal glands produce cortisol and dehydroepiandosterone-sulphate which upregulate prior to spontaneous preterm birth. Ultrasound suggests that adrenal volumes may increase prior to preterm birth, but studies are limited. This study aimed to: (i) demonstrate reproducibility of magnetic resonance imaging (MRI) derived adrenal volumetry; (ii) derive normal ranges of total adrenal volumes, and adrenal: body volume for normal; (iii) compare with those who have spontaneous very preterm birth; and (iv) correlate with histopathological chorioamnionitis. MATERIAL AND METHODS: Patients at high risk of preterm birth prior to 32 weeks were prospectively recruited, and included if they did deliver prior to 32 weeks; a control group who delivered an uncomplicated pregnancy at term was also recruited. T2 weighted images of the entire uterus were obtained, and a deformable slice-to-volume method was used to reconstruct the fetal abdomen. Adrenal and body volumes were obtained via manual segmentation, and adrenal: body volume ratios generated. Normal ranges were created using control data. Differences between groups were investigated accounting for the effect of gestation by use of regression analysis. Placental histopathology was reviewed for pregnancies delivering preterm. RESULTS: A total of 56 controls and 26 cases were included in the analysis. Volumetry was consistent between observers. Adrenal volumes were not higher in the case group (p = 0.2); adrenal: body volume ratios were higher (p = 0.011), persisting in the presence of chorioamnionitis (p = 0.017). A cluster of three pairs of adrenal glands below the fifth centile were noted among the cases all of whom had a protracted period at risk of preterm birth prior to MRI. CONCLUSIONS: Adrenal: body volume ratios are significantly larger in fetuses who go on to deliver preterm than those delivering at term. Adrenal volumes were not significantly larger, we hypothesize that this could be due to an adrenal atrophy in fetuses with fulminating chorioamnionitis. A straightforward relationship of adrenal size being increased prior to preterm birth should not be assumed.
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Corioamnionitis , Nacimiento Prematuro , Embarazo , Femenino , Humanos , Recién Nacido , Nacimiento Prematuro/diagnóstico por imagen , Corioamnionitis/diagnóstico por imagen , Proyectos Piloto , Reproducibilidad de los Resultados , Placenta , FetoRESUMEN
INTRODUCTION: Spontaneous preterm birth complicates â¼7% of pregnancies and causes morbidity and mortality. Although infection is a common etiology, our understanding of the fetal immune system in vivo is limited. This study aimed to utilize T2-weighted imaging and T2* relaxometry (which is a proxy of tissue oxygenation) of the fetal spleen in uncomplicated pregnancies and in fetuses that were subsequently delivered spontaneously prior to 32 weeks. METHODS: Women underwent imaging including T2-weighted fetal body images and multi-eco gradient echo single-shot echo planar sequences on a Phillips Achieva 3T system. Previously described postprocessing techniques were applied to obtain T2- and T2*-weighted imaging of the fetal spleen and T2-weighted fetal body volumes. RESULTS: Among 55 women with uncomplicated pregnancies, an increase in fetal splenic volume, splenic:body volume, and a decrease in splenic T2* signal intensity was demonstrated across gestation. Compared to controls, fetuses who were subsequently delivered prior to 32 weeks' gestation (n = 19) had a larger spleen when controlled for the overall size of the fetus (p = 0.027), but T2* was consistent (p = 0.76). CONCLUSION: These findings provide evidence of a replicable method of studying the fetal immune system and give novel results on the impact of impending preterm birth on the spleen. While T2* decreases prior to preterm birth in other organs, preservation demonstrated here suggests preferential sparing of the spleen.
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Imagen por Resonancia Magnética , Nacimiento Prematuro , Bazo , Humanos , Femenino , Bazo/diagnóstico por imagen , Embarazo , Nacimiento Prematuro/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adulto , Edad Gestacional , Feto/diagnóstico por imagenRESUMEN
BACKGROUND: Preterm prelabour rupture of membranes (PPROM) is a common obstetric condition but outcomes can vary depending on gestation. Significant maternal and foetal complications occur including preterm birth, infection, abruption, cord prolapse, pulmonary hypoplasia and even death. Although the need for psychological support is recognised it is unclear how much is actually offered to women and their families. This study aimed to survey the views of women and their families who have undergone PPROM in order to understand the care and psychological burden these families face. METHODS: An online survey was conducted, recruiting women via social media with collaboration from the patient advocacy support group Little Heartbeats. Responses were collated where fields were binary or mean and standard deviations calculated. Framework analysis was used to identify and analyse themes in free text responses. RESULTS: 180PPROM pregnancies were described from 177 respondents. Although carewas variable and respondents were from across the world there werecommon themes. Five themes were highlighted which were: a lack ofbalanced information regarding the condition, support in decisionmaking and support with the process, specific psychological supportand ongoing psychological consequences of PPROM. CONCLUSION: This survey highlights areas in which care needs to be improved for women with PPROM. Previous studies have shown that providing good care during the antenatal period reduces long-term psychological morbidity for the whole family. The need for support, with regard both to information provided to women and their families and their psychological support needs to be addressed urgently.
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Background The benefits of using low-field-strength fetal MRI to evaluate antenatal development include reduced image artifacts, increased comfort, larger bore size, and potentially reduced costs, but studies about fetal low-field-strength MRI are lacking. Purpose To evaluate the reliability and feasibility of low-field-strength fetal MRI to assess anatomic and functional measures in pregnant participants using a commercially available 0.55-T MRI scanner and a comprehensive 20-minute protocol. Materials and Methods This prospective study was performed at a large teaching hospital (St Thomas' Hospital; London, England) from May to November 2022 in healthy pregnant participants and participants with pregnancy-related abnormalities using a commercially available 0.55-T MRI scanner. A 20-minute protocol was acquired including anatomic T2-weighted fast-spin-echo, quantitative T2*, and diffusion sequences. Key measures like biparietal diameter, transcerebellar diameter, lung volume, and cervical length were evaluated by two radiologists and an MRI-experienced obstetrician. Functional organ-specific mean values were given. Comparison was performed with existing published values and higher-field MRI using linear regression, interobserver correlation, and Bland-Altman plots. Results A total of 79 fetal MRI examinations were performed (mean gestational age, 29.4 weeks ± 5.5 [SD] [age range, 17.6-39.3 weeks]; maternal age, 34.4 years ± 5.3 [age range, 18.4-45.5 years]) in 47 healthy pregnant participants (control participants) and in 32 participants with pregnancy-related abnormalities. The key anatomic two-dimensional measures for the 47 healthy participants agreed with large cross-sectional 1.5-T and 3-T control studies. The interobserver correlations for the biparietal diameter in the first 40 consecutive scans were 0.96 (95% CI: 0.7, 0.99; P = .002) for abnormalities and 0.93 (95% CI: 0.86, 0.97; P < .001) for control participants. Functional features, including placental and brain T2* and placental apparent diffusion coefficient values, strongly correlated with gestational age (mean placental T2* in the control participants: 5.2 msec of decay per week; R2 = 0.66; mean T2* at 30 weeks, 176.6 msec; P < .001). Conclusion The 20-minute low-field-strength fetal MRI examination protocol was capable of producing reliable structural and functional measures of the fetus and placenta in pregnancy. Clinical trial registration no. REC 21/LO/0742 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Gowland in this issue.
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Imagen por Resonancia Magnética , Placenta , Adolescente , Adulto , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Adulto Joven , Estudios Transversales , Estudios de Factibilidad , Feto , Imagen por Resonancia Magnética/métodos , Estudios Prospectivos , Reproducibilidad de los ResultadosRESUMEN
PURPOSE: Preterm premature rupture of membranes complicates up to 40% of premature deliveries. Fetal infection may occur in the absence of maternal symptoms, delaying diagnosis and increasing morbidity and mortality. A noninvasive antenatal assessment of early signs of placental inflammation is therefore urgently required. METHODS: Sixteen women with preterm premature rupture of membranes < 34 weeks gestation and 60 women with uncomplicated pregnancies were prospectively recruited. A modified diffusion-weighted spin-echo single shot EPI sequence with a diffusion preparation acquiring 264 unique parameter combinations in < 9 min was obtained on a clinical 3 Tesla MRI scanner. The data was fitted to a 2-compartment T 2 * $$ {\mathrm{T}}_2^{\ast } $$ -intravoxel incoherent motion model comprising fast and slowly circulating fluid pools to obtain quantitative information on perfusion, density, and tissue composition. Z values were calculated, and correlation with time from between the rupture of membranes and the scan, gestational age at delivery, and time between scan and delivery assessed. RESULTS: Placental T 2 * $$ {\mathrm{T}}_2^{\ast } $$ was significantly reduced in preterm premature rupture of membranes, and the 2-compartmental model demonstrated that this decline is mainly linked to the perfusion component observed in the placental parenchyma. Multi-modal MRI measurement of placental function is linked to gestational age at delivery and time from membrane rupture. CONCLUSION: More complex models and data acquisition can potentially improve fitting of the underlying etiology of preterm birth compared with individual single-contrast models and contribute to additional insights in the future. This will need validation in larger cohorts. A multi-modal MRI acquisition between rupture of the membranes and delivery can be used to measure placental function and is linked to gestational age at delivery.
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Rotura Prematura de Membranas Fetales , Nacimiento Prematuro , Femenino , Recién Nacido , Embarazo , Humanos , Nacimiento Prematuro/diagnóstico por imagen , Placenta/diagnóstico por imagen , Rotura Prematura de Membranas Fetales/diagnóstico por imagen , Edad Gestacional , InflamaciónRESUMEN
BACKGROUND: Preterm prelabour rupture of the membranes (PPROM) complicates 3% of pregnancies and is associated with an increased risk of maternal and perinatal morbidity and mortality. In an attempt to better understand this diagnosis, patients routinely resort to the internet for medical information. The lack of governance online leaves patients at risk of relying on low-quality websites. OBJECTIVES: To assess systematically the accuracy, quality, readability and credibility of World Wide Web pages on PPROM. SEARCH STRATEGY: Five search engines (Google, AOL, Yahoo, Ask and Bing) were searched with location services and browser history disabled. Websites from the first page of all searches were included. SELECTION CRITERIA: Websites were included if they provided at least 300 words of health information aimed at patients relating to PPROM. DATA COLLECTION AND ANALYSIS: Validated assessments of health information readability, credibility and quality were undertaken, as was an accuracy assessment. Pertinent facts for accuracy assessment were based on feedback from healthcare professionals and patients through a survey. Characteristics were tabulated. MAIN RESULTS: In all, 39 websites were included, with 31 different texts. No pages were written with a reading age of 11 years or less, none were considered credible, and only three were high quality. An accuracy score of 50% or more was obtained by 45% of websites. Information that patients considered pertinent was not consistently reported. CONCLUSIONS: Search engines produce information on PPROM that is low quality, low accuracy and not credible. It is also difficult to read. This risks disempowerment. Healthcare professionals and researchers must consider how to ensure patients have access to information that they can recognise as high quality.
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Rotura Prematura de Membranas Fetales , Embarazo , Femenino , Recién Nacido , Humanos , Niño , ComprensiónRESUMEN
Like many social behaviors, aggression can be rewarding, leading to behavioral plasticity. One outcome of reward-induced aggression is the long-term increase in the speed in which future aggression-based encounters is initiated. This form of aggression impacts dendritic structure and excitatory synaptic neurotransmission in the nucleus accumbens, a brain region well known to regulate motivated behaviors. Yet, little is known about the intracellular signaling mechanisms that drive these structural/functional changes and long-term changes in aggressive behavior. This study set out to further elucidate the intracellular signaling mechanisms regulating the plasticity in neurophysiology and behavior that underlie the rewarding consequences of aggressive interactions. Female Syrian hamsters experienced zero, two or five aggressive interactions and the phosphorylation of proteins in reward-associated regions was analyzed. We report that aggressive interactions result in a transient increase in the phosphorylation of extracellular-signal related kinase 1/2 (ERK1/2) in the nucleus accumbens. We also report that aggressive interactions result in a transient decrease in the phosphorylation of mammalian target of rapamycin (mTOR) in the medial prefrontal cortex, a major input structure to the nucleus accumbens. Thus, this study identifies ERK1/2 and mTOR as potential signaling pathways for regulating the long-term rewarding consequences of aggressive interactions. Furthermore, the recruitment profile of the ERK1/2 and the mTOR pathways are distinct in different brain regions.
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Sistema de Señalización de MAP Quinasas , Núcleo Accumbens , Cricetinae , Animales , Femenino , Núcleo Accumbens/metabolismo , Mesocricetus , Fosforilación , Agresión/fisiología , Corteza Prefrontal/metabolismo , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Chorioamnionitis is present in up to 70% of spontaneous preterm births. It is defined as an acute inflammation of the chorion, with or without involvement of the amnion, and is evidence of a maternal immunological response to infection. A fetal inflammatory response can coexist and is diagnosed on placental histopathology postnatally. Fetal inflammatory response syndrome (FIRS) is associated with poorer fetal and neonatal outcomes. The only antenatal diagnostic test is amniocentesis which carries risks of miscarriage or preterm birth. Imaging of the fetal immune system, in particular the thymus and the spleen, and the placenta may give valuable information antenatally regarding the diagnosis of fetal inflammatory response. While ultrasound is largely limited to structural information, MRI can complement this with functional information that may provide insight into the metabolic activities of the fetal immune system and placenta. This review discusses fetal and placental imaging in pregnancies complicated by chorioamnionitis and their potential future use in achieving non-invasive antenatal diagnosis.
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Corioamnionitis , Nacimiento Prematuro , Amniocentesis , Corioamnionitis/diagnóstico por imagen , Femenino , Enfermedades Fetales , Humanos , Recién Nacido , Placenta/diagnóstico por imagen , Placenta/patología , Embarazo , Síndrome de Respuesta Inflamatoria SistémicaRESUMEN
BACKGROUND: Ethnically minoritised people have been disproportionately affected by the COVID-19 pandemic. Emerging evidence suggests a lower uptake of the vaccine in ethnically minoritised people, particularly Black females of reproductive age. Unvaccinated pregnant women are high risk for morbidity and mortality from COVID-19. Midwives are the principal healthcare professionals responsible for counselling the pregnant population on decisions relating to vaccine uptake. The aim of this study was to explore midwifery uptake of and attitudes towards the COVID-19 vaccine in two ethnically diverse areas. METHODS: A 45-point questionnaire was circulated over a six-week period to midwives employed in two teaching hospitals in England; London (Barts Health NHS Trust) and Sussex (Brighton and Sussex University Hospitals NHS Trust (BSUH)). A total of 378 out of 868 midwives responded. Results were analysed to determine vaccine uptake as well as factors influencing vaccine hesitancy and decision-making between the two trusts and ethnic groups. Thematic analysis was also undertaken. RESULTS: Midwives of Black ethnicities were over 4-times less likely to have received a COVID-19 vaccine compared to midwives of White ethnicities (52% vs 85%, adjusted OR = 0.22, p = < 0.001). Overall, there were no significant differences between trusts in receipt of the COVID-19 vaccine (p = 0.13). Midwives at Barts Health were significantly more likely to have tested positive for COVID-19 compared to midwives at BSUH (adjusted OR = 2.55, p = 0.007). There was no statistical difference between ethnicities in testing positive for COVID-19 (p = 0.86). The most common concerns amongst all participants were regarding the long-term effect of the vaccine (35%), that it was developed too fast (24%), having an allergic reaction (22%) and concerns about fertility (15%). Amongst unvaccinated midwives, those of Black ethnicity had a higher occurrence of concern that the vaccine contained meat / porcine products (adjusted OR = 5.93, p = 0.04) and that the vaccine would have an adverse effect on ethnic minorities (adjusted OR = 4.42, p = 0.03). CONCLUSION: This study highlights the significantly higher level of vaccine hesitancy amongst Black midwives and offer insights into midwives' concerns. This can facilitate future targeted public health interventions. It is essential that vaccine hesitancy amongst midwifery staff is addressed to improve vaccine uptake in the pregnant population.
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COVID-19 , Partería , Animales , COVID-19/prevención & control , Vacunas contra la COVID-19 , Femenino , Humanos , Pandemias/prevención & control , Embarazo , Encuestas y Cuestionarios , Porcinos , Vacunación , Vacilación a la VacunaciónRESUMEN
In skeletal muscle fibers, mitochondria are densely packed adjacent to myofibrils because adenosine triphosphate (ATP) is needed to fuel sarcomere shortening. However, despite this close physical and biochemical relationship, the effects of mitochondrial dynamics on skeletal muscle contractility are poorly understood. In this study, we analyzed the effects of Mitochondrial Division Inhibitor 1 (mdivi-1), an inhibitor of mitochondrial fission, on the structure and function of both mitochondria and myofibrils in skeletal muscle tissues engineered on micromolded gelatin hydrogels. Treatment with mdivi-1 did not alter myotube morphology, but did increase the mitochondrial turbidity and oxidative capacity, consistent with reduced mitochondrial fission. Mdivi-1 also significantly increased basal, twitch, and tetanus stresses, as measured using the Muscular Thin Film (MTF) assay. Finally, mdivi-1 increased sarcomere length, potentially due to mdivi-1-induced changes in mitochondrial volume and compression of myofibrils. Together, these results suggest that mdivi-1 increases contractile stress generation, which may be caused by an increase in maximal respiration and/or sarcomere length due to increased volume of individual mitochondria. These data reinforce that mitochondria have both biochemical and biomechanical roles in skeletal muscle and that mitochondrial dynamics can be manipulated to alter muscle contractility.
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Mitocondrias Musculares/efectos de los fármacos , Fibras Musculares Esqueléticas/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Mioblastos Esqueléticos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Quinazolinonas/farmacología , Animales , Línea Celular , Dinaminas/metabolismo , Ratones , Mitocondrias Musculares/metabolismo , Dinámicas Mitocondriales/fisiología , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/fisiología , Músculo Esquelético/citología , Músculo Esquelético/fisiología , Mioblastos Esqueléticos/citología , Mioblastos Esqueléticos/metabolismo , Oxidación-Reducción/efectos de los fármacos , Sarcómeros/efectos de los fármacos , Sarcómeros/metabolismo , Sarcómeros/fisiologíaRESUMEN
Birth is an extraordinary event for placental mammals and occurs at a time when key developmental processes are shaping the brain. Remarkably, little is known about the contributions of birth to brain development and whether birth mode (vaginal vs. Cesarean) alters neurodevelopmental trajectories. We previously reported that Cesarean birth reduces vasopressin (VP) neuron number in the hypothalamic paraventricular nucleus (PVN) of mice at weaning. In this study, we investigated whether this effect extends to adulthood and whether birth mode affects oxytocin (OT) neurons, which are another prominent population in the PVN. We found that Cesarean-born adults had fewer VP neurons in the PVN, specifically in magnocellular regions. Interestingly, these regions also had more dying cells following a Cesarean birth, suggesting that cell death may be the underlying mechanism. The PVN of Cesarean-born adults also had smaller VP neuron somas and reduced VP efferent projections. Additionally, Cesarean-born mice showed fewer and smaller OT neurons in the PVN, but these effects were less robust than for VP neurons. We also examined VP and OT neuron number in the supraoptic and suprachiasmatic nuclei but found no effect of birth mode in these regions. Thus, Cesarean birth causes long-term effects on the VP and, to a lesser extent, OT systems in the PVN, suggesting that this region is particularly sensitive to the effects of birth mode. Our findings may help explain the social deficits reported for Cesarean-born mice, and are also of clinical significance given the widespread practice of Cesarean births across the world.
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Oxitocina , Núcleo Hipotalámico Paraventricular , Animales , Femenino , Mamíferos/metabolismo , Ratones , Neuronas/metabolismo , Oxitocina/farmacología , Núcleo Hipotalámico Paraventricular/metabolismo , Placenta/metabolismo , Embarazo , Vasopresinas/metabolismoRESUMEN
PURPOSE: Methylation of ingested inorganic arsenic (InAs) to monomethyl- (MMAs) and dimethyl-arsenical species (DMAs) facilitates urinary arsenic elimination. Folate and creatine supplementation influenced arsenic methylation in a randomized controlled trial. Here, we examine if baseline status of one-carbon metabolism nutrients (folate, choline, betaine, and vitamin B12) modified the effects of FA and creatine supplementation on changes in homocysteine, guanidinoacetate (GAA), total blood arsenic, and urinary arsenic metabolite proportions and indices. METHODS: Study participants (N = 622) received 400 or 800 µg FA, 3 g creatine, 400 µg FA + 3 g creatine, or placebo daily for 12 weeks. RESULTS: Relative to placebo, FA supplementation was associated with greater mean increases in %DMAs among participants with betaine concentrations below the median than those with levels above the median (FDR < 0.05). 400 µg FA/day was associated with a greater decrease in homocysteine among participants with plasma folate concentrations below, compared with those above, the median (FDR < 0.03). Creatine treatment was associated with a significant decrease in %MMAs among participants with choline concentrations below the median (P = 0.04), but not among participants above the median (P = 0.94); this effect did not significantly differ between strata (P = 0.10). CONCLUSIONS: Effects of FA and creatine supplementation on arsenic methylation capacity were greater among individuals with low betaine and choline status, respectively. The efficacy of FA and creatine interventions to facilitate arsenic methylation may be modified by choline and betaine nutritional status. CLINICAL TRIAL REGISTRATION: Clinical Trial Registry Identifier: NCT01050556, U.S. National Library of Medicine, https://clinicaltrials.gov ; registered January 15, 2010.
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Arsénico , Adulto , Betaína , Colina , Creatina , Suplementos Dietéticos , Exposición a Riesgos Ambientales , Ácido Fólico , Homocisteína , Humanos , MetilaciónRESUMEN
Introduction. While school-based kitchen garden programs are shown to improve fruit and vegetable consumption and knowledge among children, there has been little research on participant perceptions of these programs, specifically among minority populations that are disproportionately affected by and at high risk for overweight and obesity. This qualitative study examined the perceptions of and values associated with participation in school-based kitchen garden programs implemented through Edible Schoolyard New Orleans in low-income, predominantly African American schools in New Orleans, Louisiana. Method. Qualitative data were collected through semistructured focus group discussions with key stakeholder groups at schools offering Edible Schoolyard New Orleans. Results. A total of 10 focus groups were conducted across 4 middle schools with students (n = 27), parents (n = 17), and teachers (n = 17). Four primary themes emerged during data analysis: development of life skills, food and health, family and community, and experiential and participatory learning. Conclusions. To strengthen the sustainability and potential impact of school-based kitchen garden programs, future intervention strategies should place specific emphasis on the themes that emerged from this study. School-based kitchen garden programs may be a promising strategy to positively influence the individual, social, and physical environmental factors that contribute to overweight and obesity in low-income, African American communities.
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Negro o Afroamericano , Jardines , Promoción de la Salud/organización & administración , Pobreza , Instituciones Académicas/organización & administración , Adolescente , Adulto , Niño , Femenino , Grupos Focales , Frutas , Humanos , Masculino , Persona de Mediana Edad , Nueva Orleans , Padres/educación , Investigación Cualitativa , VerdurasRESUMEN
Sour rot, a disease affecting berries of cultivated Vitis spp. worldwide, has not been clearly defined. Reported symptoms of the disease include browning of the berry skin, oozing of disintegrated berry pulp, and the smell of acetic acid, all in the presence of fruit flies (Drosophila spp.). We determined acetic acid concentrations in multiple collections of symptomatic berries, isolated and identified microbes from them, and inoculated commonly isolated organisms into healthy berries with and without concurrent exposure to wild-type or axenic Drosophila melanogaster. Coinoculations combining one of several yeasts (Metschnikowia spp., Pichia spp., and a Saccharomyces sp.) plus an acetic acid bacterium (an Acetobacter sp. and Gluconobacter spp.) reproduced sour rot symptoms, defined here as decaying berries with a loss of turgor and containing acetic acid at a minimum of 0.83 g/liter, based on observed field levels. Symptoms developed only in the presence of D. melanogaster, either wild type or axenic, indicating a nonmicrobial contribution of these insects in addition to a previously suggested microbial role. We conclude that sour rot is the culmination of coinfection by various yeasts, which convert grape sugars to ethanol, and bacteria that oxidize the ethanol to acetic acid, and that this process is mediated by Drosophila spp.