123 research outputs found
Influence of salinity and cadmium on the volume of Pacific herring eggs
Changes in total volume and volume of the yolk and perivitelline space of Pacific herring eggs were examined throughout incubation at 5°C in relation to salinity of the incubation medium (5, 20, 35‰ S), and after exposure to cadmium (0.05–10 ppm Cd) at 20‰ S. After fertilization and filling of the perivitelline space there was a decline in total egg volume in all salinities until 60–80 hr after fertilization. There followed a period of relative stability of total volume (100–240 hr), then a slow decline until hatching (240–618 hr). There was an inverse relation, between egg volume and salinity at all stages of egg development. Eggs transferred from 20‰ to 5 or 35‰ S, 87.4 hr after fertilization (90% blastodermal overgrowth of the yolk), showed only minor changes in total egg volume within the period of relative stability (100–240 hr). Prior to 80 hr, changes in egg volume appeared primarily to be simpleadjustments to prevailing osmotic and ionic conditions, modified, however, by presumed irreversible changes induced in the egg in relation to salinity experience at, and shortly after, fertilization. Subsequently, between 80–100 hr, egg volume appears to becomeregulated, commencing in the interval between late blastodermal overgrowth and blastopore closure. Yolk volume declined after fertilization, reached a minimum 40–60 hr after fertilization, increased to 100 hr, then decreased in the period of relative stability of total volume — presumably in relation to rapid growth of the embryo. In the latter period, yolk volume appeared resistant to change when eggs are transferred from 20 ‰ to 5 or 35 ‰ S, 87.4 hr, after fertilization. Volume of the perivitelline space reached a maximum after fertilization, then decreased until about 100 hr; between 100 and 240 hr it increased rapidly and was influenced only in a minor way by salinity changes in the incubation medium 87.4 hr after fertilization. Eggs exposed to cadmium in the interval between 1/2 and 30 hr after fertilization showed major reductions in total egg volume; total volume in the period of relative stability (100–240 hr) was much reduced and normal volume was not recovered after removal of such eggs to uncontaminated water at 30 hr
Very preterm infants engage in an intervention to train their control of attention: results from the feasibility study of the Attention Control Training (ACT) randomised trial
Background
Very premature birth (gestational age between 28 and 31 + 6 weeks) is associated with increased risk of cognitive delay and attention deficit disorder, which have been linked to anomalies in the development of executive functions (EFs) and their precursors. In particular, very preterm (VP) infants display anomalies in controlling attention and gathering task-relevant information. Early interventions that support attention control may be pivotal in providing a secure base for VP children’s later attainments. The Attention Control Training (ACT) is a cognitive training intervention that targets infants’ abilities to select visual information according to varying task demands but had not been tested in VP infants. We conducted a feasibility study to test the processes we intend to use in a trial delivering the ACT to VP infants.
Methods and design
We tested recruitment and retention of VP infants and their families in a randomised trial, as well as acceptability and completion of baseline and outcome measures. To evaluate these aims, we used descriptive quantitative statistics and qualitative methods to analyse feedback from infants’ caregivers. We also investigated the quality of eye-tracking data collected and indicators of infants’ engagement in the training, using descriptive statistics.
Results
Twelve VP infants were recruited, and 10 (83%) completed the study. Participants’ parents had high education attainment. The rate of completion of baseline and outcome measures was optimal. VP infants demonstrated engagement in the training, completing on average 84 min of training over three visits, and displaying improved performance during this training. Eye-tracking data quality was moderate, but this did not interfere with infants’ engagement in the training.
Discussion
The results suggest the ACT can be delivered to VP infants. However, challenges remain in recruitment of numerous and diverse samples. We discuss strategies to overcome these challenges informed by results of this study.
Trial registration
Registered Registration ID: NCT03896490. Retrospectively registered at Clinical Trials Protocol Registration and Results System (clinicaltrials.gov)
Salt and Water Retention Is Associated with Microinflammation and Endothelial Injury in Chronic Kidney Disease
BACKGROUND: Progressive chronic kidney disease (CKD) inevitably leads to salt and water retention and disturbances in the macro-and microcirculation. OBJECTIVES: We hypothesize that salt and water dysregulation in advanced CKD may be linked to inflammation and microvascular injury pathways. METHODS: We studied 23 CKD stage 5 patients and 11 healthy controls (HC). Tissue sodium concentration was assessed using 23Sodium magnetic resonance (MR) imaging. Hydration status was evaluated using bioimpedance spectroscopy. A panel of inflammatory and endothelial biomarkers was also measured. RESULTS: CKD patients had fluid overload (FO) when compared to HC (overhydration index: CKD = 0.5 ± 1.9 L vs. HC = -0.5 ± 1.0 L; p = 0.03). MR-derived tissue sodium concentrations were predominantly higher in the subcutaneous (SC) compartment (median [interquartile range] CKD = 22.4 mmol/L [19.4-31.3] vs. HC = 18.4 mmol/L [16.6-21.3]; p = 0.03), but not the muscle (CKD = 24.9 ± 5.5 mmol/L vs. HC = 22.8 ± 2.5 mmol/L; p = 0.26). Tissue sodium in both compartments correlated to FO (muscle: r = 0.63, p < 0.01; SC: rs = 0.63, p < 0.01). CKD subjects had elevated levels of vascular cell adhesion molecule (p < 0.05), tumor necrosis factor-alpha (p < 0.01), and interleukin (IL)-6 (p = 0.01) and lower levels of vascular endothelial growth factor-C (p = 0.04). FO in CKD was linked to higher IL-8 (r = 0.51, p < 0.05) and inversely associated to E-selectin (r = -0.52, p = 0.01). Higher SC sodium was linked to higher intracellular adhesion molecule (ICAM; rs = 0.54, p = 0.02). CONCLUSION: Salt and water accumulation in CKD appears to be linked with inflammation and endothelial activation pathways. Specifically IL-8, E-Selectin (in FO), and ICAM (in salt accumulation) may be implicated in the pathophysiology of FO and merit further investigation
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Conceptual framework on barriers and facilitators to implementing perinatal mental health care and treatment for women: the MATRIx evidence synthesis
Background
Perinatal mental health difficulties can occur during pregnancy or after birth and mental illness is a leading cause of maternal death. It is therefore important to identify the barriers and facilitators to implementing and accessing perinatal mental health care.
Objectives
Our research objective was to develop a conceptual framework of barriers and facilitators to perinatal mental health care (defined as identification, assessment, care and treatment) to inform perinatal mental health services.
Methods
Two systematic reviews were conducted to synthesise the evidence on: Review 1 barriers and facilitators to implementing perinatal mental health care; and Review 2 barriers to women accessing perinatal mental health care. Results were used to develop a conceptual framework which was then refined through consultations with stakeholders.
Data sources
Pre-planned searches were conducted on MEDLINE, EMBASE, PsychInfo and CINAHL. Review 2 also included Scopus and the Cochrane Database of Systematic Reviews.
Review methods
In Review 1, studies were included if they examined barriers or facilitators to implementing perinatal mental health care. In Review 2, systematic reviews were included if they examined barriers and facilitators to women seeking help, accessing help and engaging in perinatal mental health care; and they used systematic search strategies. Only qualitative papers were identified from the searches. Results were analysed using thematic synthesis and themes were mapped on to a theoretically informed multi-level model then grouped to reflect different stages of the care pathway.
Results
Review 1 included 46 studies. Most were carried out in higher income countries and evaluated as good quality with low risk of bias. Review 2 included 32 systematic reviews. Most were carried out in higher income countries and evaluated as having low confidence in the results.
Barriers and facilitators to perinatal mental health care were identified at seven levels: Individual (e.g. beliefs about mental illness); Health professional (e.g. confidence addressing perinatal mental illness); Interpersonal (e.g. relationship between women and health professionals); Organisational (e.g. continuity of carer); Commissioner (e.g. referral pathways); Political (e.g. women’s economic status); and Societal (e.g. stigma). These factors impacted on perinatal mental health care at different stages of the care pathway.
Results from reviews were synthesised to develop two MATRIx conceptual frameworks of the (1) barriers and (2) facilitators to perinatal mental health care. These provide pictorial representations of 66 barriers and 39 facilitators that intersect across the care pathway and at different levels.
Limitations
In Review 1 only 10% of abstracts were double screened and 10% of included papers methodologically appraised by two reviewers. The majority of reviews included in Review 2 were evaluated as having low (n = 14) or critically low (n = 5) confidence in their results. Both reviews only included papers published in academic journals and written in English.
Conclusions
The MATRIx frameworks highlight the complex interplay of individual and system level factors across different stages of the care pathway that influence women accessing perinatal mental health care and effective implementation of perinatal mental health services.
Recommendations for health policy and practice
These include using the conceptual frameworks to inform comprehensive, strategic and evidence-based approaches to perinatal mental health care; ensuring care is easy to access and flexible; providing culturally sensitive care; adequate funding of services; and quality training for health professionals with protected time to do it.
Future work
Further research is needed to examine access to perinatal mental health care for specific groups, such as fathers, immigrants or those in lower income countries.
Far-infrared and Raman spectra of pseudo -tetrahedral complexes of ethylenedimorpholene
The far-i.r. and Raman spectra of a closely related group of pseudo -tetrahedral complexes of general formula [MX 2 EDM] are reported (M = Co II , Ni II , Cu II , Zn II ; X = Cl or Br). EDM, ethylenedimorpholene, acts in these compounds as a bidentate nitrogen donor. The main skeletal vibrations are assigned under the approximate symmetry of the C 2v (MX 2 Y 2 ) point group.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43851/1/11243_2004_Article_BF00623421.pd
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Evaluation of perinatal anxiety assessment measures: a cognitive interview study
Background
Anxiety in pregnancy and postpartum is highly prevalent but under-recognised. To identify perinatal anxiety, assessment tools must be acceptable, relevant, and easy to use for women in the perinatal period.
Methods
To determine the acceptability and ease of use of anxiety measures to pregnant or postpartum women (n = 41) we examined five versions of four measures: the Generalised Anxiety Disorder scale (GAD) 2-item and 7-item versions; Whooley questions; Clinical Outcomes in Routine Evaluation (CORE-10); and Stirling Antenatal Anxiety Scale (SAAS). Cognitive interviews were used to examine ease of comprehension, judgement, retrieval and responding.
Results
All measures were acceptable. Some items were deemed less relevant to the perinatal period e.g., difficulties sleeping. Ease of comprehension, judgement, retrieval and responding varied, with all measures having strengths and weaknesses. The SAAS and CORE-10 had the lowest mean number of problematic components. The GAD had the highest mean number of problematic components. Non-binary response options were preferred. Preferences for time frames (e.g. one week, one month) varied. Qualitative data provides in-depth information on responses to each measure.
Conclusions
Findings can be used to inform clinical guidelines and research on acceptable anxiety assessment in pregnancy and after birth
Midwifery-led antenatal care models: mapping a systematic review to an evidence-based quality framework to identify key components and characteristics of care.
BACKGROUND: Implementing effective antenatal care models is a key global policy goal. However, the mechanisms of action of these multi-faceted models that would allow widespread implementation are seldom examined and poorly understood. In existing care model analyses there is little distinction between what is done, how it is done, and who does it. A new evidence-informed quality maternal and newborn care (QMNC) framework identifies key characteristics of quality care. This offers the opportunity to identify systematically the characteristics of care delivery that may be generalizable across contexts, thereby enhancing implementation. Our objective was to map the characteristics of antenatal care models tested in Randomised Controlled Trials (RCTs) to a new evidence-based framework for quality maternal and newborn care; thus facilitating the identification of characteristics of effective care. METHODS: A systematic review of RCTs of midwifery-led antenatal care models. Mapping and evaluation of these models' characteristics to the QMNC framework using data extraction and scoring forms derived from the five framework components. Paired team members independently extracted data and conducted quality assessment using the QMNC framework and standard RCT criteria. RESULTS: From 13,050 citations initially retrieved we identified 17 RCTs of midwifery-led antenatal care models from Australia (7), the UK (4), China (2), and Sweden, Ireland, Mexico and Canada (1 each). QMNC framework scores ranged from 9 to 25 (possible range 0-32), with most models reporting fewer than half the characteristics associated with quality maternity care. Description of care model characteristics was lacking in many studies, but was better reported for the intervention arms. Organisation of care was the best-described component. Underlying values and philosophy of care were poorly reported. CONCLUSIONS: The QMNC framework facilitates assessment of the characteristics of antenatal care models. It is vital to understand all the characteristics of multi-faceted interventions such as care models; not only what is done but why it is done, by whom, and how this differed from the standard care package. By applying the QMNC framework we have established a foundation for future reports of intervention studies so that the characteristics of individual models can be evaluated, and the impact of any differences appraised
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Mindfulness-based cognitive therapy for psychological distress in pregnancy: study protocol for a randomized controlled trial
BACKGROUND: Clinically significant psychological distress in pregnancy is common, with epidemiological research suggesting that between 15 and 25 % of pregnant women experience elevated symptoms of stress, anxiety, and depression. Untreated psychological distress in pregnancy is associated with poor obstetrical outcomes, changes in maternal physiology, elevated incidence of child physical and psychological disorders, and is predictive of maternal postpartum mood disorders. Despite the wide-ranging impact of antenatal psychological distress on mothers and their children, there is a gap in our knowledge about the most effective treatments that are available for psychological distress experienced in pregnancy. Additionally, no trials have focused on potential physiological changes that may occur as a result of receiving mindfulness training in pregnancy. The proposed trial will determine the effectiveness of an 8-week modified Mindfulness-based Cognitive Therapy (MBCT) intervention delivered during pregnancy. METHODS: A randomized controlled trial (RCT) design with repeated measures will be used to evaluate the effectiveness of MBCT to treat psychological distress in pregnancy. A sample of 60 consenting pregnant women aged 18 years and above will be enrolled and randomized to the experimental (MBCT) or control (treatment as usual) condition. Primary (e.g., symptoms of stress, depression, and anxiety), secondary (cortisol, blood pressure (BP), heart rate variability (HRV), and sleep) and other outcome data (e.g., psychological diagnoses) will be collected via a combination of laboratory visits and at-home assessments from both groups at baseline (T(1)), immediately following the intervention (T(2)), and at 3 months postpartum (T(3)). Descriptive statistics will be used to describe sample characteristics. Data will be analyzed using an intention-to-treat approach. Hierarchical linear models will be used to test intervention effects on primary and secondary outcomes. DISCUSSION: The trial is expected to improve knowledge about evidence-based treatments for psychological distress experienced in pregnancy and to evaluate the potential impact of mindfulness-based interventions on maternal physiology. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02214732, registered on 7 August 2014. Protocol Version 2.0., 5 September 2016. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13063-016-1601-0) contains supplementary material, which is available to authorized users
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