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1.
Magn Reson Med ; 92(3): 1263-1276, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38650351

RESUMO

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.


Assuntos
Encéfalo , Feto , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/embriologia , Imageamento por Ressonância Magnética/métodos , Feminino , Gravidez , Feto/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Aprendizado Profundo , Diagnóstico Pré-Natal/métodos , Estudos Prospectivos , Imagem Ecoplanar/métodos , Algoritmos , Interpretação de Imagem Assistida por Computador/métodos
2.
BJOG ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956748

RESUMO

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.

3.
Prenat Diagn ; 44(1): 49-56, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38126921

RESUMO

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.


Assuntos
Nascimento Prematuro , Recém-Nascido , Feminino , Humanos , Nascimento Prematuro/diagnóstico por imagem , Projetos Piloto , Lactente Extremamente Prematuro , Imageamento por Ressonância Magnética/métodos , Feto , Encéfalo
4.
Acta Obstet Gynecol Scand ; 103(3): 512-521, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38009386

RESUMO

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.


Assuntos
Corioamnionite , Nascimento Prematuro , Gravidez , Feminino , Humanos , Recém-Nascido , Nascimento Prematuro/diagnóstico por imagem , Corioamnionite/diagnóstico por imagem , Projetos Piloto , Reprodutibilidade dos Testes , Placenta , Feto
5.
Fetal Diagn Ther ; : 1-13, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857593

RESUMO

INTRODUCTION: Spontaneous preterm birth complicates ∼7% 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.

6.
J Reprod Infant Psychol ; : 1-18, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38361489

RESUMO

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.

7.
Radiology ; 309(1): e223050, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37847139

RESUMO

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.


Assuntos
Imageamento por Ressonância Magnética , Placenta , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Adulto Jovem , Estudos Transversais , Estudos de Viabilidade , Feto , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos , Reprodutibilidade dos Testes
8.
Magn Reson Med ; 89(3): 1151-1159, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36255151

RESUMO

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.


Assuntos
Ruptura Prematura de Membranas Fetais , Nascimento Prematuro , Feminino , Recém-Nascido , Gravidez , Humanos , Nascimento Prematuro/diagnóstico por imagem , Placenta/diagnóstico por imagem , Ruptura Prematura de Membranas Fetais/diagnóstico por imagem , Idade Gestacional , Inflamação
9.
BJOG ; 130(11): 1298-1305, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37077130

RESUMO

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.


Assuntos
Ruptura Prematura de Membranas Fetais , Gravidez , Feminino , Recém-Nascido , Humanos , Criança , Compreensão
10.
Int J Mol Sci ; 24(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36674893

RESUMO

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.


Assuntos
Sistema de Sinalização das MAP Quinases , Núcleo Accumbens , Cricetinae , Animais , Feminino , Núcleo Accumbens/metabolismo , Mesocricetus , Fosforilação , Agressão/fisiologia , Córtex Pré-Frontal/metabolismo , Serina-Treonina Quinases TOR/metabolismo
11.
Prenat Diagn ; 42(8): 1049-1058, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35670265

RESUMO

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.


Assuntos
Corioamnionite , Nascimento Prematuro , Amniocentese , Corioamnionite/diagnóstico por imagem , Feminino , Doenças Fetais , Humanos , Recém-Nascido , Placenta/diagnóstico por imagem , Placenta/patologia , Gravidez , Síndrome de Resposta Inflamatória Sistêmica
12.
BMC Public Health ; 22(1): 1219, 2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35717164

RESUMO

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.


Assuntos
COVID-19 , Tocologia , Animais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Feminino , Humanos , Pandemias/prevenção & controle , Gravidez , Inquéritos e Questionários , Suínos , Vacinação , Hesitação Vacinal
13.
FASEB J ; 34(9): 11562-11576, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32652761

RESUMO

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.


Assuntos
Mitocôndrias Musculares/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Mioblastos Esqueléticos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Quinazolinonas/farmacologia , Animais , Linhagem Celular , Dinaminas/metabolismo , Camundongos , Mitocôndrias Musculares/metabolismo , Dinâmica Mitocondrial/fisiologia , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/citologia , Músculo Esquelético/fisiologia , Mioblastos Esqueléticos/citologia , Mioblastos Esqueléticos/metabolismo , Oxirredução/efeitos dos fármacos , Sarcômeros/efeitos dos fármacos , Sarcômeros/metabolismo , Sarcômeros/fisiologia
14.
Horm Behav ; 136: 105080, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34749276

RESUMO

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.


Assuntos
Ocitocina , Núcleo Hipotalâmico Paraventricular , Animais , Feminino , Mamíferos/metabolismo , Camundongos , Neurônios/metabolismo , Ocitocina/farmacologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Placenta/metabolismo , Gravidez , Vasopressinas/metabolismo
15.
Eur J Nutr ; 60(4): 1921-1934, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32918135

RESUMO

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.


Assuntos
Arsênio , Adulto , Betaína , Colina , Creatina , Suplementos Nutricionais , Exposição Ambiental , Ácido Fólico , Homocisteína , Humanos , Metilação
16.
Health Promot Pract ; 20(5): 667-674, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-29882427

RESUMO

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.


Assuntos
Negro ou Afro-Americano , Jardins , Promoção da Saúde/organização & administração , Pobreza , Instituições Acadêmicas/organização & administração , Adolescente , Adulto , Criança , Feminino , Grupos Focais , Frutas , Humanos , Masculino , Pessoa de Meia-Idade , Nova Orleans , Pais/educação , Pesquisa Qualitativa , Verduras
17.
Phytopathology ; 108(12): 1429-1442, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29969063

RESUMO

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.


Assuntos
Ácido Acético/metabolismo , Bactérias/metabolismo , Drosophila melanogaster/fisiologia , Doenças das Plantas/etiologia , Saccharomyces cerevisiae/fisiologia , Vitis/microbiologia , Animais , Frutas/microbiologia , Doenças das Plantas/microbiologia
19.
J Nutr ; 146(5): 1062-7, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27052531

RESUMO

BACKGROUND: Folic acid (FA) supplementation facilitates urinary excretion of arsenic, a human carcinogen. A better understanding of interactions between one-carbon metabolism intermediates may improve the ability to design nutrition interventions that further facilitate arsenic excretion. OBJECTIVE: The objective was to determine if FA and/or creatine supplementation increase choline and betaine and decrease dimethylglycine (DMG). METHODS: We conducted a secondary analysis of the Folic Acid and Creatine Trial, a randomized trial in arsenic-exposed Bangladeshi adults (n = 605, aged 24-55 y, 50.3% male) who received arsenic-removal water filters. We examined treatment effects of FA and/or creatine supplementation on plasma choline, betaine, and DMG concentrations, measured by LC-tandem mass spectrometry at baseline and at week 12. Group comparisons were between 1) 400 and 800 µg FA/d (FA400 and FA800, respectively) compared with placebo, 2) creatine (3 g/d) compared with placebo, and 3) creatine plus FA400 compared with FA400. RESULTS: Choline decreased in the placebo group (-6.6%; 95% CI: -10.2%, -2.9%) but did not change in the FA groups (FA400: 2.5%; 95% CI: -0.9%, 6.1%; FA800: 1.4%; 95% CI: -2.5%, 5.5%; P < 0.05). Betaine did not change in the placebo group (-3.5%; 95% CI: -9.3%, 2.6%) but increased in the FA groups (FA400: 14.1%; 95% CI: 9.4%, 19.0%; FA800: 13.0%; 95% CI: 7.2%, 19.1%; P < 0.01). The decrease in DMG was greater in the FA groups (FA400: -26.7%; 95% CI: -30.9%, -22.2%; FA800: -27.8%; 95% CI: -31.8%, -23.4%) than in the placebo group (-12.3%; 95% CI: -18.1%, -6.2%; P < 0.01). The percentage change in choline, betaine, and DMG did not differ between creatine treatment arms and their respective reference groups. CONCLUSION: Supplementation for 12 wk with FA, but not creatine, increases plasma betaine, decreases plasma DMG, and prevents a decrease in plasma choline in arsenic-exposed Bangladeshi adults. This trial was registered at clinicaltrials.gov as NCT01050556.


Assuntos
Arsênio/urina , Betaína/sangue , Colina/sangue , Creatina/farmacologia , Suplementos Nutricionais , Ácido Fólico/farmacologia , Sarcosina/análogos & derivados , Adulto , Bangladesh , Exposição Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sarcosina/sangue , Espectrometria de Massas em Tandem , Complexo Vitamínico B/farmacologia , Adulto Jovem
20.
Reprod Health Matters ; 24(47): 104-17, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27578344

RESUMO

The prevalence of violence against women worldwide raises the question of the desirability and feasibility of integrating interpersonal violence (IPV) services within abortion care. By examining present services and context in an Inner London borough in the UK, this situation analysis explored the hypothesis that an established, integrated, health-based service (comprising raised awareness, staff training in routine IPV enquiry and referral to a community-based in-reach IPV service) would be transferable into abortion services. Four sources of qualitative data investigated views on integrating services: key stakeholder in-depth interviews including with providers of abortion and IPV services and commissioners and IPV survivors with past abortion service use (3 user, 15 provider); qualitative analysis of the open-ended part of a survey of current abortion service users with and without experience of IPV; feedback from an interactive workshop and data from field observations. While there was consensus among all informants that women experiencing IPV and seeking abortion have unidentified, unaddressed needs, how any intervention might be organised to address these needs was contested; thus questions remain about whether, when and how to raise the topic of IPV and what to offer. Two major anxieties surfaced: a practical concern in terms of interrupting a streamlined abortion service that suits the majority of staff and patients, and a conceptual concern about risk of stigmatising abortion seekers as 'victims in crisis'. Thus, our findings indicate: when integrating IPV interventions into abortion services, local context, the integrity of separate pathways, and women's safety and agency must be considered, especially when abortion rights are under attack. Novel approaches are required and should be researched.


Assuntos
Instituições de Assistência Ambulatorial/tendências , Violência por Parceiro Íntimo/estatística & dados numéricos , Violência/estatística & dados numéricos , Adulto , Feminino , Humanos , Entrevistas como Assunto , Londres/epidemiologia , Gravidez
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