93 research outputs found

    Acute atherosis and oxidative stressin preeclampsia

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    Preeclampsia is complicating 3.5% of pregnancies in Norway, and is associated with increased mortality and morbidity for both mother and offspring. Deficient placentation with release of substances from the placenta to the maternal circulation is believed to cause hypertension and proteinuria, which are diagnostic of the disease. The uterine endometrium (decidua) contains blood vessels that are important for placental nutritional transport to the fetus. The walls of these spiral arteries often contain lipid depositions (acute atherosis), causing reduced blood flow to the placenta, hypoxia and oxidative stress. Gynecologist Nina Kittelsen Harsem demonstrated that a new method for collecting decidual tissue after delivery was better than traditional knife biopsies from the uterine endometrium, as more spiral arteries were collected for demonstration of lipid deposition in morphological investigations. The lipid depositions in the spiral artery walls were more frequent in women with preeclampsia than in women with normal pregnancies, but not all women with preeclampsia demonstrated these vascular changes. In addition, some few women with apparently healthy pregnancies also demonstrated similar evidence of arterial lipid deposition. Among circulating substances found in increased concentration in preeclampsia are oxidized lipids, including isoprostanes, which could result in a state of increased oxidative stress. In the preeclampsia group there was evidence of augmented oxidative stress in the maternal circulation. In the fetal umbilical cord blood there was not found any difference between preeclampsia and controls. She then explored whether there is an association between the lipid deposition in the spiral arterial wall and signs of augmented oxidative stress in maternal blood, but no such association were demonstrated. This study supports the concept that preeclampsia is a heterogeneous disease that does not affect all women, fetuses or placentas similarly

    Experimental study on the thermal plume from a surgeon in an operating room with mixing ventilation during COVID-19 pandemic

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    Following the outbreak of COVID-19 (SARS-CoV-2) in 2019, studies show positive results in protecting the surgical staff from patients infected by COVID-19 in operating rooms (ORs) with negative pressure. A negative pressure environment inside the operating room (OR) reduces the virus's circulation outside the OR (Chen et al., 2020). Nevertheless, it is unclear whether the surgeon's thermal plume can impact the transport of contaminants up to the breathing zone and thus cause infection in ORs with various pressure differences compared to adjacent rooms. The results show that a gap between the surgical manikin and the operating table greatly affects the development of the thermal plume from the head surgeon. A plate between the surgical manikin and the operating table may significantly influence the airflow distribution in front of the head surgeon more than the pressure difference inside the operating room.publishedVersio

    Cardiac morphology in neonates with fetal growth restriction

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    Objective: Assess effects of fetal growth restriction (FGR) on cardiac modelling in premature and term neonates. Study design: Prospective echocardiographic study of a cohort of FGR neonates (n = 21) and controls (n = 41) with normal prenatal growth and circulation. Results: Unadjusted for gestational age, birth weight, sex, and twin/singleton, Late-FGR neonates had smaller hearts than controls, with globular left ventricles and symmetrical right ventricles. Adjusted estimates showed smaller left ventricles and similarly sized right ventricles, with symmetrical left and right ventricles. Early-FGR (compared with Late-FGR) had smaller hearts and globular left ventricles in unadjusted estimates, but after adjustment, sizes and shapes were similar. Conclusion: FGR had significant impact on cardiac modelling, seen in both statistical models unadjusted and adjusted for gestational age, birth weight, sex, and twin/singleton. The adjustments, however, refined the results and revealed more specific effects of FGR, thus underscoring the importance of statistical adjustments in such studies.acceptedVersio

    Experimental Study on the Surgical Microenvironment in an Operating Room with Mixing Ventilation under Positive and Negative Pressure

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    Due to the outbreak of Covid-19, negative pressure operating room (NPOR) are strongly recommended to be applied to prevent spreading virus from infected patients to adjacent rooms during surgery procedures. However, there have been few experimental studies on the effect of OR pressure difference on the surgical microenvironment. This study aims to experimentally investigate the airflow distribution in the surgical microenvironment in an OR under different pressure conditions. All measurements were performed in a fullscale laboratory, which has an area of 62 m2, and a mixing ventilation. The air velocity and temperature in the surgical microenvironment of a lying patient were measured under positive pressure of 5 Pa, 10 Pa, 15 Pa and negative pressure of -5 Pa, -10 Pa and -15 Pa. The effect of heat generated by operating lamps was also considered. The results show that the airflow distribution around the surgical wound is dominated by thermal plume from the patient under the condition of both positive and negative pressure. In other areas of the surgical microenvironment, regardless the pressure difference conditions, the room airflow distribution by ventilation system is the dominant factor on surgical microenvironment. Variations in differential pressure can affect the temperature distribution around the surgical site, with a smaller differential pressure producing a slightly larger vertical temperature gradient.publishedVersio

    Fetal sex-specific differences in gestational age at delivery in pre-eclampsia : a meta-analysis

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    Background: Pre-eclampsia (PE) is a major pregnancy disorder complicating up to 8% of pregnancies. Increasing evidence indicates a sex-specific interplay between the mother,placenta and fetus. This may lead to different adaptive mechanisms during pregnancy. Methods: We performed an individual participant data meta-analysis to determine associations of fetal sex and PE, with specific focus on gestational age at delivery in PE. This was done on 219 575 independent live-born singleton pregnancies, with a gestational age at birth between 22.0 and 43.0 weeks of gestation, from 11 studies participating in a worldwide consortium of international research groups focusing on pregnancy. Results: Of the women, 9033 (4.1%) experienced PE in their pregnancy and 48.8% of the fetuses were female versus 51.2% male. No differences in the female/male distribution were observed with respect to term PE (delivered >= 37 weeks). Preterm PE (delivered <37 weeks) was slightly more prevalent among pregnancies with a female fetus than in pregnancies with a male fetus [odds ratio (OR) 1.11, 95% confidence interval (CI) 1.02-1.21]. Very preterm PE (delivered <34 weeks) was even more prevalent among pregnancies with a female fetus as compared with pregnancies with a male fetus (OR 1.36, 95% CI 1.17-1.59). Conclusions: Sexual dimorphic differences in the occurrence of PE exist, with preterm PE being more prevalent among pregnancies with a female fetus as compared with pregnancies with a male fetus and with no differences with respect to term PE.Peer reviewe

    Stakeholder-informed ecosystem modeling of ocean warming and acidification impacts in the barents sea region

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    Climate change and ocean acidification are anticipated to alter marine ecosystems, with consequences for the provision of marine resources and ecosystem services to human societies. However, considerable uncertainties about future ecological changes and ensuing socio-economic impacts impede the identification of societal adaptation strategies. In a case study from the Barents Sea and Northern Norwegian Sea region, we integrated stakeholder perceptions of ecological changes and their significance for societies with the current state of scientific knowledge, to investigate the marine-human system under climate change and identify societal adaptation options. Stakeholders were engaged through personal interviews, two local workshops, and a web based survey, identifying the most relevant ecosystem services potentially impacted and developing an integrated system dynamics model which links climate change scenarios to the response of relevant species. Stakeholder perceptions of temperature-dependent multiannual fluctuations of fish stocks, interactions among fish, marine mammal, and seabird populations, and ecological processes such as primary production are represented in the model. The model was used for a discourse-based stakeholder evaluation of potential ecosystem changes under ocean warming and acidification scenarios, identifying shifts in ecosystem service provision and discussing associated societal adaptation options. The results pointed to differences in adaptive capacity among user groups. Small-scale fishers and tourism businesses are potentially more affected by changing spatial distribution and local declines in marine species than industrial fisheries. Changes in biodiversity, especially extinctions of polar species, and ecosystem functioning were a concern from an environmental conservation viewpoint. When considering potential additional impacts of ocean acidification, changes observed in the model projections were more uniformly valued as negative, and associated with an increased potential for conflicts among user groups. The stakeholder-informed ecosystem modeling approach has succeeded in driving a discussion and interchange among stakeholder groups and with scientists, integrating knowledge about climate change impacts in the social-ecological system and identifying important factors that shape societal responses. The approach can thus serve to improve governance of marine systems by incorporating knowledge about system dynamics and about societal uses and values

    Fetal sex-specific differences in gestational age at delivery in pre-eclampsia: a meta-analysis

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    Background: : Pre-eclampsia (PE) is a major pregnancy disorder complicating up to 8% of pregnancies. Increasing evidence indicates a sex-specific interplay between the mother, placenta and fetus. This may lead to different adaptive mechanisms during pregnancy.Methods: We performed an individual participant data meta-analysis to determine associations of fetal sex and PE, with specific focus on gestational age at delivery in PE. This was done on 219 575 independent live-born singleton pregnancies, with a gestational age at birth between 22.0 and 43.0 weeks of gestation, from 11 studies participating in a worldwide consortium of international research groups focusing on pregnancy.Results: Of the women, 9033 (4.1%) experienced PE in their pregnancy and 48.8% of the fetuses were female versus 51.2% male. No differences in the female/male distribution were observed with respect to term PE (delivered ≥ 37 weeks). Preterm PE (delivered < 37 weeks) was slightly more prevalent among pregnancies with a female fetus than in pregnancies with a male fetus [odds ratio (OR) 1.11, 95% confidence interval (CI) 1.02-1.21]. Very preterm PE (delivered < 34 weeks) was even more prevalent among pregnancies with a female fetus as compared with pregnancies with a male fetus (OR 1.36, 95% CI 1.17-1.59).Conclusions: Sexual dimorphic differences in the occurrence of PE exist, with preterm PE being more prevalent among pregnancies with a female fetus as compared with pregnancies with a male fetus and with no differences with respect to term PE

    Determination of glucose exchange rates and permeability of erythrocyte membrane in preeclampsia and subsequent oxidative stress-related protein damage using dynamic-19F-NMR

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    The cause of the pregnancy condition preeclampsia (PE) is thought to be endothelial dysfunction caused by oxidative stress. As abnormal glucose tolerance has also been associated with PE, we use a fluorinated-mimic of this metabolite to establish whether any oxidative damage to lipids and proteins in the erythrocyte membrane has increased cell membrane permeability. Data were acquired using 19F Dynamic-NMR (DNMR) to measure exchange of 3-fluoro-3-deoxyglucose (3-FDG) across the membrane of erythrocytes from 10 pregnant women (5 healthy control women, and 5 from women suffering from PE). Magnetisation transfer was measured using the 1D selective inversion and 2D EXSY pulse sequences, over a range of time delays. Integrated intensities from these experiments were used in matrix diagonalisation to estimate the values of the rate constants of exchange and membrane permeability. No significant differences were observed for the rate of exchange of 3-FDG and membrane permeability between healthy pregnant women and those suffering from PE, leading us to conclude that no oxidative damage had occurred at this carrier-protein site in the membrane
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