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1.
Aust N Z J Public Health ; 47(5): 100076, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37620243

ABSTRACT

OBJECTIVE: To explore risk factors for smoking susceptibility among Australian adolescents to inform prevention policies and programs. METHODS: Cross-sectional survey of students aged 12-17 years who reported having never smoked (n=4,171). Bivariate associations between smoking susceptibility and a range of factors previously linked to youth smoking and smoking susceptibility were initially examined, with significant factors (p<0.05) included in a final multivariable logistic regression model. RESULTS: Eleven percent of adolescents who had never smoked were susceptible to smoking. Smoking susceptibility was independently associated with ever use of e-cigarettes (adjusted odds ratio [AOR]=3.26, 95% confidence interval [CI]: 1.83-5.81), perceiving those who smoke to be more popular (AOR=2.87, 95% CI: 1.62-5.10), having a close friend/s who smokes (AOR=2.66, 95% CI: 1.61-4.40), not perceiving smoking one or two cigarettes occasionally as personally dangerous (AOR=2.56, 95% CI: 1.61-4.09), and having symptoms of depression (AOR=1.59, 95% CI: 1.06-2.38). CONCLUSIONS: The strongest smoking-initiation risk factor identified was ever use of e-cigarettes, with social norms, harm misperceptions around low-rate tobacco use and mental health also linked to smoking susceptibility. IMPLICATIONS FOR PUBLIC HEALTH: Stronger e-cigarette regulations that reduce promotion to and access by youth, as well as interventions addressing the other identified risk factors, may help prevent future smoking uptake among Australian adolescents.

2.
Drug Alcohol Rev ; 42(1): 59-67, 2023 01.
Article in English | MEDLINE | ID: mdl-36067077

ABSTRACT

INTRODUCTION: Widespread commercial promotion of alcohol products in Australia undermines the abstinence message for young people. This study aims to document the frequency of adolescents' exposure to alcohol advertising and examine associations with drinking behaviours. METHODS: Students aged 12-17 years (n = 3618) participating in a cross-sectional survey self-reported their exposure to alcohol advertising via eight sources. Students also indicated whether they had never consumed alcohol, consumed at least a few sips of alcohol in their lifetime but none in the past month ('irregular drinkers') or consumed more than 10 drinks in their lifetime including at least one drink in the past month ('drinkers'). Multinomial logistic regression analyses examined associations between both single-channel and cumulative exposure to alcohol advertising and drinking status, controlling for sex, age and education sector. RESULTS: Television (61%), the internet (56%) and at sporting events (50%) were the most common channels through which students reported seeing alcohol advertising. Weekly exposure via each of the eight assessed channels was associated with being a drinker (vs. a non-drinker or an irregular drinker, respectively), whereas only weekly exposure via television and sporting events was associated with being an irregular drinker (vs. a non-drinker). As students' level of cumulative exposure to alcohol advertising increased, so too did their likelihood of being a drinker. DISCUSSION AND CONCLUSIONS: Alcohol advertising exposure is positively associated with drinking among Australian adolescents. Tighter restrictions on alcohol advertising across all media in Australia may reduce adolescent exposure and help de-normalise alcohol use.


Subject(s)
Advertising , Alcohol Drinking , Adolescent , Humans , Alcohol Drinking/epidemiology , Australia/epidemiology , Cross-Sectional Studies , Ethanol , Child
4.
Nat Commun ; 11(1): 6391, 2020 12 15.
Article in English | MEDLINE | ID: mdl-33319779

ABSTRACT

Skin color patterns are ubiquitous in nature, impact social behavior, predator avoidance, and protection from ultraviolet irradiation. A leading model system for vertebrate skin patterning is the zebrafish; its alternating blue stripes and yellow interstripes depend on light-reflecting cells called iridophores. It was suggested that the zebrafish's color pattern arises from a single type of iridophore migrating differentially to stripes and interstripes. However, here we find that iridophores do not migrate between stripes and interstripes but instead differentiate and proliferate in-place, based on their micro-environment. RNA-sequencing analysis further reveals that stripe and interstripe iridophores have different transcriptomic states, while cryogenic-scanning-electron-microscopy and micro-X-ray diffraction identify different crystal-arrays architectures, indicating that stripe and interstripe iridophores are different cell types. Based on these results, we present an alternative model of skin patterning in zebrafish in which distinct iridophore crystallotypes containing specialized, physiologically responsive, organelles arise in stripe and interstripe by in-situ differentiation.


Subject(s)
Cell Differentiation/physiology , Chromatophores/physiology , Chromatophores/ultrastructure , Skin Pigmentation/physiology , Skin/ultrastructure , Zebrafish/metabolism , Animals , Cell Differentiation/genetics , Cell Proliferation/physiology , Microphthalmia-Associated Transcription Factor , Mutagenesis , Skin/metabolism , Skin Pigmentation/genetics , Transcriptome , X-Ray Diffraction , Zebrafish/genetics , Zebrafish Proteins/genetics
5.
Proc Natl Acad Sci U S A ; 116(24): 11806-11811, 2019 06 11.
Article in English | MEDLINE | ID: mdl-31138706

ABSTRACT

Understanding genetic and cellular bases of adult form remains a fundamental goal at the intersection of developmental and evolutionary biology. The skin pigment cells of vertebrates, derived from embryonic neural crest, are a useful system for elucidating mechanisms of fate specification, pattern formation, and how particular phenotypes impact organismal behavior and ecology. In a survey of Danio fishes, including the zebrafish Danio rerio, we identified two populations of white pigment cells-leucophores-one of which arises by transdifferentiation of adult melanophores and another of which develops from a yellow-orange xanthophore or xanthophore-like progenitor. Single-cell transcriptomic, mutational, chemical, and ultrastructural analyses of zebrafish leucophores revealed cell-type-specific chemical compositions, organelle configurations, and genetic requirements. At the organismal level, we identified distinct physiological responses of leucophores during environmental background matching, and we showed that leucophore complement influences behavior. Together, our studies reveal independently arisen pigment cell types and mechanisms of fate acquisition in zebrafish and illustrate how concerted analyses across hierarchical levels can provide insights into phenotypes and their evolution.


Subject(s)
Cell Plasticity/genetics , Zebrafish/genetics , Zebrafish/physiology , Animals , Embryo, Nonmammalian/physiology , Gene Expression Regulation, Developmental/genetics , Genetics, Population/methods , Melanophores/physiology , Mutation/genetics , Neural Crest/physiology , Phenotype , Pigmentation/genetics , Transcriptome/genetics
6.
PLoS Genet ; 14(9): e1007538, 2018 09.
Article in English | MEDLINE | ID: mdl-30226839

ABSTRACT

Fishes of the genus Danio exhibit diverse pigment patterns that serve as useful models for understanding the genes and cell behaviors underlying the evolution of adult form. Among these species, zebrafish D. rerio exhibit several dark stripes of melanophores with sparse iridophores that alternate with light interstripes of dense iridophores and xanthophores. By contrast, the closely related species D. nigrofasciatus has an attenuated pattern with fewer melanophores, stripes and interstripes. Here we demonstrate species differences in iridophore development that presage the fully formed patterns. Using genetic and transgenic approaches we identify the secreted peptide Endothelin-3 (Edn3)-a known melanogenic factor of tetrapods-as contributing to reduced iridophore proliferation and fewer stripes and interstripes in D. nigrofasciatus. We further show the locus encoding this factor is expressed at lower levels in D. nigrofasciatus owing to cis-regulatory differences between species. Finally, we show that functions of two paralogous loci encoding Edn3 have been partitioned between skin and non-skin iridophores. Our findings reveal genetic and cellular mechanisms contributing to pattern differences between these species and suggest a model for evolutionary changes in Edn3 requirements for pigment patterning and its diversification across vertebrates.


Subject(s)
Chromatophores/physiology , Endothelin-3/metabolism , Pigmentation/genetics , Zebrafish Proteins/metabolism , Zebrafish/physiology , Animals , Animals, Genetically Modified , Cell Proliferation , Embryo, Nonmammalian , Endothelin-3/genetics , Evolution, Molecular , Gene Expression Regulation, Developmental/physiology , Models, Animal , Phenotype , Signal Transduction/genetics , Skin/cytology , Species Specificity , Zebrafish Proteins/genetics
8.
Aust N Z J Obstet Gynaecol ; 56(1): 113-6, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26757351

ABSTRACT

Outcomes in gestational diabetes Cochrane protocols and reviews before and after development of 'standard outcomes' by WOMBAT (WOMen and Babies health and well-being: Action through Trials) were surveyed. An increase in 'common' outcomes (those prespecified by ≥50% of the protocols and reviews) over time was observed (2001-2009: 27 vs 2010-2014: 46). There were discrepancies in outcomes prespecified in reviews and reported by randomised trials. Efforts are needed to develop a core outcome set, to reduce research waste and improve health outcomes.


Subject(s)
Diabetes, Gestational , Outcome Assessment, Health Care/standards , Randomized Controlled Trials as Topic , Review Literature as Topic , Diabetes, Gestational/diagnosis , Diabetes, Gestational/therapy , Female , Humans , Outcome Assessment, Health Care/methods , Pregnancy
9.
Elife ; 42015 Dec 23.
Article in English | MEDLINE | ID: mdl-26701906

ABSTRACT

Changes in gene activity are essential for evolutionary diversification. Yet, elucidating the cellular behaviors that underlie modifications to adult form remains a profound challenge. We use neural crest-derived adult pigmentation of zebrafish and pearl danio to uncover cellular bases for alternative pattern states. We show that stripes in zebrafish require a novel class of thin, fast cellular projection to promote Delta-Notch signaling over long distances from cells of the xanthophore lineage to melanophores. Projections depended on microfilaments and microtubules, exhibited meandering trajectories, and stabilized on target cells to which they delivered membraneous vesicles. By contrast, the uniformly patterned pearl danio lacked such projections, concomitant with Colony stimulating factor 1-dependent changes in xanthophore differentiation that likely curtail signaling available to melanophores. Our study reveals a novel mechanism of cellular communication, roles for differentiation state heterogeneity in pigment cell interactions, and an unanticipated morphogenetic behavior contributing to a striking difference in adult form.


Subject(s)
Cell Communication , Cyprinidae/physiology , Gene Expression Regulation , Melanophores/physiology , Pigments, Biological/metabolism , Secretory Vesicles/metabolism , Signal Transduction , Animals , Cyprinidae/genetics
10.
Cochrane Database Syst Rev ; (9): CD011263, 2015 Sep 21.
Article in English | MEDLINE | ID: mdl-26387772

ABSTRACT

BACKGROUND: Thyroid dysfunction pre-pregnancy and during pregnancy (both hyper- and hypothyroidism) is associated with increased risk of adverse outcomes for mothers and infants in the short- and long-term. Managing the thyroid dysfunction (e.g. thyroxine for hypothyroidism, or antithyroid medication for hyperthyroidism) may improve outcomes. The best method of screening to identify and subsequently manage thyroid dysfunction pre-pregnancy and during pregnancy is unknown. OBJECTIVES: To assess the effects of different screening methods (and subsequent management) for thyroid dysfunction pre-pregnancy and during pregnancy on maternal and infant outcomes. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (14 July 2015) and reference lists of retrieved studies. SELECTION CRITERIA: Randomised or quasi-randomised controlled trials, comparing any screening method (e.g. tool, program, guideline/protocol) for detecting thyroid dysfunction (including hypothyroidism, hyperthyroidism, and/or thyroid autoimmunity) pre-pregnancy or during pregnancy with no screening, or alternative screening methods. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed eligibility of studies, extracted and checked data accuracy, and assessed the risk of bias of included studies. MAIN RESULTS: We included two randomised controlled trials (involving 26,408 women) - these trials were considered to be at low risk of bias. Universal screening (screening all women) versus case finding (screening only those at perceived increased risk) in pregnancy for thyroid dysfunctionOne trial (4562 women) compared universal screening with case finding for thyroid dysfunction. Before 11 weeks' gestation, women in the universal screening group, and 'high-risk' women in the case finding group had their sera tested for TSH (thyroid stimulating hormone), fT4 (free thyroxine) and TPO-Ab (thyroid peroxidase antibody); women with hypothyroidism (TSH > 2.5 mIU/litre) received levothyroxine; women with hyperthyroidism (undetectable TSH and elevated fT4) received antithyroid medication.In regards to this review's primary outcomes, compared with the case finding group, more women in the universal screening group were diagnosed with hypothyroidism (risk ratio (RR) 3.15, 95% confidence interval (CI) 1.91 to 5.20; 4562 women; GRADE: high quality evidence), with a trend towards more women being diagnosed with hyperthyroidism (RR 4.50, 95% CI 0.97 to 20.82; 4562 women; P = 0.05; GRADE: moderate quality evidence). No clear differences were seen in the risks of pre-eclampsia (RR 0.87, 95% CI 0.64 to 1.18; 4516 women; GRADE: moderate quality evidence), or preterm birth (RR 0.99, 95% CI 0.80 to 1.24; 4516 women; GRADE: high quality evidence) between groups. This trial did not report on neurosensory disability for the infant as a child.Considering this review's secondary outcomes, more women in the universal screening group received pharmacological treatment for thyroid dysfunction (RR 3.15, 95% CI 1.91 to 5.20; 4562 women). No clear differences between groups were observed for miscarriage (RR 0.90, 95% CI 0.68 to 1.19; 4516 women; GRADE: moderate quality evidence), fetal and neonatal death (RR 0.92, 95% CI 0.42 to 2.02; 4516 infants; GRADE: moderate quality evidence), or other secondary outcomes: pregnancy-induced hypertension, gestational diabetes, congestive heart failure, thyroid storm, mode of birth (caesarean section), preterm labour, placental abruption, respiratory distress syndrome, low birthweight, neonatal intensive care unit admission, or other congenital malformations. The trial did not report on a number of outcomes including adverse effects associated with the intervention. Universal screening versus no screening in pregnancy for hypothyroidismOne trial (21,846 women) compared universal screening with no screening for hypothyroidism. Before 15 + 6 weeks' gestation, women in the universal screening group had their sera tested; women who screened 'positive' (TSH > 97.5th percentile, fT4 < 2.5th percentile, or both) received levothyroxine.Considering primary review outcomes, compared with the no screening group, more women in the universal screening screened 'positive' for hypothyroidism (RR 998.18, 95% CI 62.36 to 15,978.48; 21,839 women; GRADE: high quality evidence). No data were provided for the outcome pre-eclampsia, and for preterm birth, the trial reported rates of 5.6% and 7.9% for the screening and no screening groups respectively (it was unclear if these percentages related to the entire cohort or women who screened positive). No clear difference was seen for neurosensory disability for the infant as a child (three-year follow-up IQ score < 85) (RR 0.85, 95% CI 0.60 to 1.22; 794 infants; GRADE: moderate quality evidence).More women in the universal screening group received pharmacological treatment for thyroid dysfunction (RR 1102.90, 95% CI 69.07 to 17,610.46; 1050 women); 10% had their dose lowered because of low TSH, high fT4 or minor side effects. No clear differences were observed for other secondary outcomes, including developmental delay/intellectual impairment at three years. Most of our secondary outcomes, including miscarriage, fetal or neonatal death were not reported. AUTHORS' CONCLUSIONS: Based on the existing evidence, though universal screening for thyroid dysfunction in pregnancy increases the number of women diagnosed with hypothyroidism who can be subsequently treated, it does not clearly impact (benefit or harm) maternal and infant outcomes.While universal screening versus case finding for thyroid dysfunction increased diagnosis and subsequent treatment, we found no clear differences for the primary outcomes: pre-eclampsia or preterm birth. No clear differences were seen for secondary outcomes, including miscarriage and fetal or neonatal death; data were lacking for the primary outcome: neurosensory disability for the infant as a child, and for many secondary outcomes. Though universal screening versus no screening for hypothyroidism similarly increased diagnosis and subsequent treatment, no clear difference was seen for the primary outcome: neurosensory disability for the infant as a child (IQ < 85 at three years); data were lacking for the other primary outcomes: pre-eclampsia and preterm birth, and for the majority of secondary outcomes.For outcomes assessed using the GRADE approach the evidence was considered to be moderate or high quality, with any downgrading of the evidence based on the presence of wide confidence intervals crossing the line of no effect.More evidence is needed to assess the benefits or harms of different screening methods for thyroid dysfunction in pregnancy, on maternal, infant and child health outcomes. Future trials should assess impacts on use of health services and costs, and be adequately powered to evaluate the effects on short- and long-term outcomes.


Subject(s)
Infant Health , Pregnancy Complications/diagnosis , Pregnancy Complications/therapy , Thyroid Diseases/diagnosis , Thyroid Diseases/therapy , Adult , Female , Humans , Hypothyroidism/diagnosis , Hypothyroidism/therapy , Infant, Newborn , Mass Screening , Pre-Eclampsia/diagnosis , Pre-Eclampsia/therapy , Preconception Care , Pregnancy , Randomized Controlled Trials as Topic
11.
BMC Pregnancy Childbirth ; 15: 176, 2015 Aug 18.
Article in English | MEDLINE | ID: mdl-26283623

ABSTRACT

BACKGROUND: Strong evidence supports administration of magnesium sulphate prior to birth at less than 30 weeks' gestation to prevent very preterm babies dying or developing cerebral palsy. This study was undertaken as part of The WISH (Working to Improve Survival and Health for babies born very preterm) Project, to assess health professionals' self-reported use of antenatal magnesium sulphate, and barriers and enablers to implementation of 2010 Australian and New Zealand clinical practice guidelines. METHODS: Semi-structured, one-to-one interviews were conducted with obstetric and neonatal consultants and trainees, and midwives in 2011 (n = 24) and 2012-2013 (n = 21) at the Women's and Children's Hospital, South Australia. Transcribed interview data were coded using the Theoretical Domains Framework (describing 14 domains related to behaviour change) for analysis of barriers and enablers. RESULTS: In 2012-13, health professionals more often reported 'routinely' or 'sometimes' administering or advising their colleagues to administer magnesium sulphate for fetal neuroprotection (86% in 2012-13 vs. 46% in 2011). 'Knowledge and skills', 'memory, attention and decision processes', 'environmental context and resources', 'beliefs about consequences' and 'social influences' were key domains identified in the barrier and enabler analysis. Perceived barriers were the complex administration processes, time pressures, and the unpredictability of preterm birth. Enablers included education for staff and women at risk of very preterm birth, reminders and 'prompts', simplified processes for administration, and influential colleagues. CONCLUSIONS: This study has provided valuable data on barriers and enablers to implementing magnesium sulphate for fetal neuroprotection, with implications for designing and modifying future behaviour change strategies, to ensure optimal uptake of this neuroprotective therapy for very preterm infants.


Subject(s)
Cerebral Palsy/prevention & control , Guideline Adherence/statistics & numerical data , Magnesium Sulfate/therapeutic use , Neuroprotective Agents/therapeutic use , Perinatal Death/prevention & control , Practice Guidelines as Topic , Premature Birth , Attitude of Health Personnel , Clinical Competence , Female , Humans , Infant, Extremely Premature , Infant, Newborn , Infant, Premature , Midwifery , Neonatology , Obstetrics , Pregnancy , Reminder Systems , South Australia , Time Factors
12.
Aust N Z J Obstet Gynaecol ; 55(3): 233-8, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26084194

ABSTRACT

BACKGROUND: Australian and New Zealand clinical practice guidelines, endorsed by the NHMRC in 2010, recommend administration of antenatal magnesium sulphate to women at risk of imminent preterm birth at less than 30 weeks' gestation to reduce the risk of their very preterm babies dying or having cerebral palsy. The purpose of the ongoing Working to Improve Survival and Health for babies born very preterm (WISH) implementation project is to monitor and improve the uptake of this neuroprotective therapy across Australia and New Zealand. AIMS: To quantify and explore reasons for nonreceipt of antenatal magnesium sulphate at the Women's and Children's Hospital, in Adelaide, South Australia. MATERIALS AND METHODS: Data from the case records of women who gave birth between 23(+0) and 29(+6) weeks' gestation from 2010 to mid-2013 were reviewed to determine the proportion of eligible mothers not receiving antenatal magnesium sulphate and to explore reason(s) for nonreceipt over this time period. RESULTS: There was a reduction in the proportion of eligible mothers not receiving antenatal magnesium sulphate from 2010 (69.7%) to 2011 (26.9%), which was maintained in 2012 and 2013 (22.5%). In 2012-2013, nonreceipt was predominantly associated with immediately imminent (advanced labour, rapid progression of labour) or indicated emergent birth (actual or suspected maternal or fetal compromise). CONCLUSIONS: Use of antenatal magnesium sulphate at the Women's and Children's Hospital is now predominantly in-line with the binational guideline recommendations. Ongoing education and enhanced familiarity with procedures may facilitate timely administration in the context of some precipitous or immediately imminent births.


Subject(s)
Guideline Adherence/trends , Hospitals, Maternity/trends , Hospitals, Pediatric/trends , Magnesium Sulfate/administration & dosage , Premature Birth/drug therapy , Tocolytic Agents/administration & dosage , Adult , Cerebral Palsy/prevention & control , Cesarean Section , Female , Fetal Distress/diagnosis , Gestational Age , Hospitals, Maternity/standards , Hospitals, Pediatric/standards , Humans , Labor Onset , Medical Audit , Parity , Practice Guidelines as Topic , Pregnancy , South Australia , Young Adult
13.
Cochrane Database Syst Rev ; (4): CD010443, 2015 Apr 12.
Article in English | MEDLINE | ID: mdl-25864059

ABSTRACT

BACKGROUND: Gestational diabetes mellitus (GDM) is associated with a wide range of adverse health consequences for women and their babies in the short and long term. With an increasing prevalence of GDM worldwide, there is an urgent need to assess strategies for GDM prevention, such as combined diet and exercise interventions. OBJECTIVES: To assess the effects of combined diet and exercise interventions for preventing GDM and associated adverse health consequences for women and their babies. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (11 February 2014) and reference lists of retrieved studies. We updated the search in February 2015 but these results have not yet been incorporated and are awaiting classification. SELECTION CRITERIA: Randomised controlled trials (RCTs) and cluster-RCTs assessing the effects of interventions that included diet and exercise components. We included studies where combined diet and exercise interventions were compared with no intervention (i.e. standard care).We planned to also compare diet and exercise interventions with alternative diet and/or exercise interventions but no trials were identified for this comparison. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed study eligibility, extracted data and assessed the risk of bias of the included studies. Data were checked for accuracy. MAIN RESULTS: We included 13 randomised controlled trials (involving 4983 women and their babies). We assessed the included trials as being of moderate risk of bias overall.When comparing women receiving a diet and exercise intervention with those receiving no intervention, there was no clear difference in the risk of developing GDM (average risk ratio (RR) 0.92, 95% confidence interval (CI) 0.68 to 1.23; 11 trials, 3744 women), caesarean section (RR 0.92, 95% CI 0.83 to 1.01; seven trials, 3246 women), or large-for-gestational age (RR 0.90, 95% CI 0.77 to 1.05; 2950 infants). Only one trial reported on perinatal mortality, and found no clear difference in the risk of stillbirth (RR 0.99, 95% CI 0.29 to 3.42; 2202 fetuses) or neonatal death (RR 0.99, 95% CI 0.06 to 15.85; 2202 neonates).Very few differences were shown between groups for the review's secondary outcomes, including for induction of labour, perineal trauma, pre-eclampsia, postpartum haemorrhage and infection, macrosomia, birthweight, small-for-gestational age, ponderal index, neonatal hypoglycaemia requiring treatment, hyperbilirubinaemia requiring treatment, shoulder dystocia, bone fracture or nerve palsy. Women receiving a combined diet and exercise intervention were, however, found to have a reduced risk of preterm birth compared with women receiving no intervention (RR 0.71, 95% CI 0.55 to 0.93; five trials, 2713 women).A trend towards reduced weight gain during pregnancy was shown for women receiving the combined diet and exercise intervention (mean difference (MD) -0.76 kg, 95% CI -1.55 to 0.03; eight trials, 2707 women; P = 0.06, random-effects); but no clear difference in postnatal weight retention was observed overall.In relation to adherence to the interventions, a number of trials that reported on behaviour modifications showed benefits in diet- (5/8 trials) and physical activity- (4/8 trials) related behaviours for women receiving the combined diet and exercise intervention, compared with women receiving no intervention; however there was notable variation across trials in outcomes measured and results observed. Only two trials reported on well-being and quality of life of women, and did not observe differences between groups for these outcomes.Very few trials reported on outcomes relating to the use of health services, although one trial suggested a reduced length of antenatal hospital stay for women receiving a combined diet and exercise intervention (MD -0.27 days, 95% CI -0.49 to -0.05; 2153 women).No information was available on outcomes for the infant as a child or adult, or for most longer-term outcomes for the mother. AUTHORS' CONCLUSIONS: There are limitations associated with the available RCT evidence on the effects of combined diet and exercise interventions during pregnancy for preventing GDM. Results from 13 RCTs (of moderate quality) suggest no clear difference in the risk of developing GDM for women receiving a combined diet and exercise intervention compared with women receiving no intervention. However, the ability to draw firm conclusions was limited by variations in the quality of trials, characteristics of the interventions and populations assessed, and outcome definitions between trials.Based on the data currently available, conclusive evidence is not available to guide practice. Further large, well-designed RCTs, addressing the limitations of previous studies, are needed to assess the effects of combined interventions on preventing GDM and other relevant pregnancy outcomes including caesarean birth, large-for-gestational age and perinatal mortality. Health service utilisation and costs, and longer-term outcomes for mothers and their babies should be included. We identified another 16 trials which are ongoing and we will consider these for inclusion in the next update of this review.


Subject(s)
Diabetes, Gestational/prevention & control , Diet , Exercise , Cesarean Section/statistics & numerical data , Female , Humans , Pregnancy , Randomized Controlled Trials as Topic
14.
Cochrane Database Syst Rev ; (12): CD010846, 2014 Dec 19.
Article in English | MEDLINE | ID: mdl-25523279

ABSTRACT

BACKGROUND: Creatine is an amino acid derivative and, when phosphorylated (phosphocreatine), is involved in replenishing adenosine triphosphate (ATP) via the creatine kinase reaction. Cells obtain creatine from a diet rich in fish, meat, or dairy and by endogenous synthesis from the amino acids arginine, glycine, and methionine in an approximate 50:50 ratio. Animal studies have shown that creatine may provide fetal neuroprotection when given to the mother through her diet in pregnancy. It is important to assess whether maternally administered creatine in human pregnancy (at times of known, suspected, or potential fetal compromise) may offer neuroprotection to the fetus and may accordingly reduce the risk of adverse neurodevelopmental outcomes, such as cerebral palsy and associated impairments and disabilities arising from fetal brain injury. OBJECTIVES: To assess the effects of creatine when used for neuroprotection of the fetus. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 November 2014). SELECTION CRITERIA: We planned to include all published, unpublished, and ongoing randomised trials and quasi-randomised trials. We planned to include studies reported as abstracts only as well as full-text manuscripts. Trials using a cross-over or cluster-randomised design were not eligible for inclusion.We planned to include trials comparing creatine given to women in pregnancy for fetal neuroprotection (regardless of the route, timing, dose, or duration of administration) with placebo, no treatment, or with an alternative agent aimed at providing fetal neuroprotection. We also planned to include comparisons of different regimens for administration of creatine. DATA COLLECTION AND ANALYSIS: We identified no completed or ongoing randomised controlled trials. MAIN RESULTS: We found no randomised controlled trials for inclusion in this review. AUTHORS' CONCLUSIONS: As we did not identify any randomised controlled trials for inclusion in this review, we are unable to comment on implications for practice. Although evidence from animal studies has supported a fetal neuroprotective role for creatine when administered to the mother during pregnancy, no trials assessing creatine in pregnant women for fetal neuroprotection have been published to date. If creatine is established as safe for the mother and her fetus, research efforts should first be directed towards randomised trials comparing creatine with either no intervention (ideally using a placebo), or with alternative agents aimed at providing fetal neuroprotection (including magnesium sulphate for the very preterm infant). If appropriate, these trials should then be followed by studies comparing different creatine regimens (dosage and duration of exposure). Such trials should be high quality and adequately powered to evaluate maternal and infant short and longer-term outcomes (including neurodevelopmental disabilities such as cerebral palsy), and should consider utilisation/costs of health care.


Subject(s)
Brain Diseases/prevention & control , Creatine/therapeutic use , Fetal Diseases/prevention & control , Neuroprotective Agents/therapeutic use , Female , Humans , Pregnancy
15.
Nat Commun ; 5: 5299, 2014 Nov 06.
Article in English | MEDLINE | ID: mdl-25374113

ABSTRACT

Fishes have diverse pigment patterns, yet mechanisms of pattern evolution remain poorly understood. In zebrafish, Danio rerio, pigment-cell autonomous interactions generate dark stripes of melanophores that alternate with light interstripes of xanthophores and iridophores. Here, we identify mechanisms underlying the evolution of a uniform pattern in D. albolineatus in which all three pigment cell classes are intermingled. We show that in this species xanthophores differentiate precociously over a wider area, and that cis regulatory evolution has increased expression of xanthogenic Colony Stimulating Factor-1 (Csf1). Expressing Csf1 similarly in D. rerio has cascading effects, driving the intermingling of all three pigment cell classes and resulting in the loss of stripes, as in D. albolineatus. Our results identify novel mechanisms of pattern development and illustrate how pattern diversity can be generated when a core network of pigment-cell autonomous interactions is coupled with changes in pigment cell differentiation.


Subject(s)
Biological Evolution , Body Patterning/physiology , Cell Communication/physiology , Melanocytes/cytology , Pigmentation/physiology , Zebrafish/anatomy & histology , Zebrafish/physiology , Animals , Body Patterning/genetics , Cell Differentiation/physiology , Female , Gene Expression Regulation, Developmental/genetics , Gene Expression Regulation, Developmental/physiology , Macrophage Colony-Stimulating Factor/genetics , Macrophage Colony-Stimulating Factor/physiology , Male , Melanocytes/physiology , Phenotype , Signal Transduction/genetics , Signal Transduction/physiology , Species Specificity , Time Factors , Zebrafish/classification
16.
Cochrane Database Syst Rev ; (10): CD010660, 2014 Oct 21.
Article in English | MEDLINE | ID: mdl-25331331

ABSTRACT

BACKGROUND: Asthma is the most common respiratory disorder complicating pregnancy, and is associated with a range of adverse maternal and perinatal outcomes. There is strong evidence however, that the adequate control of asthma can improve health outcomes for mothers and their babies. Despite known risks of poorly controlled asthma during pregnancy, a large proportion of women have sub-optimal asthma control, due to concerns surrounding risks of pharmacological agents, and uncertainties regarding the effectiveness and safety of different management strategies. OBJECTIVES: To assess the effects of interventions (pharmacologic and non-pharmacologic) for managing women's asthma in pregnancy on maternal and fetal/infant outcomes. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (2 June 2014) and the Cochrane Airways Group's Trials Register (4 June 2014). SELECTION CRITERIA: Randomised and quasi-randomised controlled trials comparing any intervention used to manage asthma in pregnancy, with placebo, no intervention, or an alternative intervention. We included pharmacological and non-pharmacological interventions (including combined interventions). Cluster-randomised trials were eligible for inclusion (but none were identified). Cross-over trials were not eligible for inclusion.We included multi-armed trials along with two-armed trials. We also included studies published as abstracts only. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed trial eligibility and quality and extracted data. Data were checked for accuracy. MAIN RESULTS: We included eight trials in this review, involving 1181 women and their babies. Overall we judged two trials to be at low risk of bias, two to be of unclear risk of bias, and four to be at moderate risk of bias.Five trials assessed pharmacological agents, including inhaled corticosteroids (beclomethasone or budesonide), inhaled magnesium sulphate, intravenous theophylline, and inhaled beclomethasone verus oral theophylline. Three trials assessed non-pharmacological interventions, including a fractional exhaled nitric oxide (FENO)-based algorithm versus a clinical guideline-based algorithm to adjust inhaled corticosteroid therapy, a pharmacist-led multi-disciplinary approach to management versus standard care, and progressive muscle relaxation (PMR) versus sham training.The eight included trials were assessed under seven separate comparisons. Pharmacological interventionsPrimary outcomes: one trial suggested that inhaled magnesium sulphate in addition to usual treatment could reduce exacerbation frequency in acute asthma (mean difference (MD) -2.80; 95% confidence interval (CI) -3.21 to -2.39; 60 women). One trial assessing the addition of intravenous theophylline to standard care in acute asthma did not report on exacerbations (65 women). No clear difference was shown in the risk of exacerbations with the use of inhaled beclomethasone in addition to usual treatment for maintenance therapy in one trial (risk ratio (RR) 0.36; 95% CI 0.13 to 1.05; 60 women); a second trial also showed no difference, however data were not clearly reported to allow inclusion in a meta-analysis. No difference was shown when inhaled beclomethasone was compared with oral theophylline for maintenance therapy (RR 0.88; 95% CI 0.59 to 1.33; one trial, 385 women). None of these trials reported on neonatal intensive care admissions. SECONDARY OUTCOMES: inhaled magnesium sulphate in acute asthma was shown to improve lung function measures (one trial, 60 women); intravenous theophylline in acute asthma was not associated with benefits (one trial, 65 women). No clear differences were seen with the addition of inhaled corticosteroids to routine treatment in three trials (374 women). While inhaled beclomethasone, compared with oral theophylline, significantly reduced treatment discontinuation due to adverse effects in one trial (384 women), no other differences were observed, except for higher treatment adherence with theophylline. Four of the five trials did not report on adverse effects. Non-pharmacological interventionsPrimary outcomes: in one trial, the use of a FENO-based algorithm was shown to significantly reduce asthma exacerbations (RR 0.61; 95% CI 0.41 to 0.90; 220 women); and a trend towards fewer neonatal hospitalisations was observed (RR 0.46; 95% CI 0.21 to 1.02; 214 infants). No exacerbations occurred in one trial assessing pharmacist-led management; this approach did not reduce neonatal intensive care admissions (RR 1.50; 95% CI 0.27 to 8.32; 58 infants). One trial (64 women) assessing PMR did not report on exacerbations or neonatal intensive care admissions. SECONDARY OUTCOMES: the use of a FENO-based algorithm to adjust therapy led to some improvements in quality of life scores, as well as more frequent use of inhaled corticosteroids and long-acting ß-agonists, and less frequent use of short-acting ß-agonists (one trial, 220 women). The FENO-based algorithm was associated with fewer infants with recurrent episodes of bronchiolitis in their first year of life, and a trend towards fewer episodes of croup for infants. Pharmacist-led management improved asthma control scores at six months (one trial, 60 women); PMR improved lung function and quality of life measures (one trial, 64 women). No other differences between comparisons were observed. AUTHORS' CONCLUSIONS: Based on eight included trials, of moderate quality overall, no firm conclusions about optimal interventions for managing asthma in pregnancy can be made. Five trials assessing pharmacological interventions did not provide clear evidence of benefits or harms to support or refute current practice. While inhaled magnesium sulphate for acute asthma was shown to reduce exacerbations, this was in one small trial of unclear quality, and thus this finding should be interpreted with caution. Three trials assessing non-pharmacological interventions provided some support for the use of such strategies, however were not powered to detect differences in important maternal and infant outcomes. While a FENO-based algorithm reduced exacerbations, the effects on perinatal outcomes were less certain, and thus widespread implementation is not yet appropriate. Similarly, though positive effects on asthma control were shown with PMR and pharmacist-led management, the evidence to date is insufficient to draw definitive conclusions.In view of the limited evidence base, further randomised trials are required to determine the most effective and safe interventions for asthma in pregnancy. Future trials must be sufficiently powered, and well-designed, to allow differences in important outcomes for mothers and babies to be detected. The impact on health services requires evaluation. Any further trials assessing pharmacological interventions should assess novel agents or those used in current practice. Encouragingly, at least five trials have been identified as planned or underway.


Subject(s)
Asthma/therapy , Pregnancy Complications/therapy , Adrenal Cortex Hormones/administration & dosage , Algorithms , Anti-Asthmatic Agents/therapeutic use , Beclomethasone/therapeutic use , Female , Humans , Magnesium Sulfate/administration & dosage , Muscle Relaxation , Nitric Oxide/administration & dosage , Pregnancy , Randomized Controlled Trials as Topic , Theophylline/therapeutic use
17.
Science ; 345(6202): 1358-61, 2014 Sep 12.
Article in English | MEDLINE | ID: mdl-25170046

ABSTRACT

Pigment patterns are useful for elucidating fundamental mechanisms of pattern formation and how these mechanisms evolve. In zebrafish, several pigment cell classes interact to generate stripes, yet the developmental requirements and origins of these cells remain poorly understood. Using zebrafish and a related species, we identified roles for thyroid hormone (TH) in pigment cell development and patterning, and in postembryonic development more generally. We show that adult pigment cells arise from distinct lineages having distinct requirements for TH and that differential TH dependence can evolve within lineages. Our findings demonstrate critical functions for TH in determining pigment pattern phenotype and highlight the potential for evolutionary diversification at the intersection of developmental and endocrine mechanisms.


Subject(s)
Body Patterning , Cell Differentiation , Cell Lineage , Melanophores/physiology , Skin Pigmentation/physiology , Thyroid Hormones/physiology , Zebrafish/embryology , Animals , Embryo, Nonmammalian/cytology , Melanophores/cytology , Melanophores/drug effects , Skin Pigmentation/genetics , Thyroid Hormones/genetics , Thyroid Hormones/pharmacology
18.
Cochrane Database Syst Rev ; (4): CD000937, 2014 Apr 03.
Article in English | MEDLINE | ID: mdl-24696187

ABSTRACT

BACKGROUND: Magnesium is an essential mineral required for regulation of body temperature, nucleic acid and protein synthesis and in maintaining nerve and muscle cell electrical potentials. Many women, especially those from disadvantaged backgrounds, have low intakes of magnesium. Magnesium supplementation during pregnancy may be able to reduce fetal growth restriction and pre-eclampsia, and increase birthweight. OBJECTIVES: To assess the effects of magnesium supplementation during pregnancy on maternal, neonatal/infant and paediatric outcomes. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 March 2013). SELECTION CRITERIA: Randomised and quasi-randomised trials assessing the effects of dietary magnesium supplementation during pregnancy were included. The primary outcomes were perinatal mortality (including stillbirth and neonatal death prior to hospital discharge), small-for-gestational age, maternal mortality and pre-eclampsia. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed study eligibility, extracted data and assessed the risk of bias of included studies. MAIN RESULTS: Ten trials involving 9090 women and their babies were included; one trial had a cluster design (with randomisation by study centre). All 10 trials randomly allocated women to either an oral magnesium supplement or a control group; in eight trials a placebo was used, and in two trials no treatment was given to the control group. In the 10 included trials, the compositions of the magnesium supplements, gestational ages at commencement, and doses administered varied, including: magnesium oxide, 1000 mg daily from ≤ four months post-conception (one trial); magnesium citrate, 365 mg daily from ≤ 18 weeks until hospitalisation after 38 weeks (one trial), and 340 mg daily from nine to 27 weeks' gestation (one trial); magnesium gluconate, 2 to 3 g from 28 weeks' gestation until birth (one trial), and 4 g daily from 23 weeks' gestation (one trial); magnesium aspartate, 15 mmol daily (three trials, commencing from either six to 21 weeks' gestation until birth, ≤ 16 weeks' gestation until birth, or < 12 weeks until birth), or 365 mg daily from 13 to 24 weeks until birth (one trial); and magnesium stearate, 128 mg elemental magnesium from 10 to 35 weeks until birth (one trial).In the analysis of all trials, oral magnesium supplementation compared to no magnesium was associated with no significant difference in perinatal mortality (stillbirth and neonatal death prior to discharge) (risk ratio (RR) 1.10; 95% confidence interval (CI) 0.72 to 1.67; five trials, 5903 infants), small-for-gestational age (RR 0.76; 95% CI 0.54 to 1.07; three trials, 1291 infants), or pre-eclampsia (RR 0.87; 95% CI 0.58 to 1.32; three trials, 1042 women). None of the included trials reported on maternal mortality.Considering secondary outcomes, while no increased risk of stillbirth was observed, a possible increased risk of neonatal death prior to hospital discharge was shown for infants born to mothers who had received magnesium (RR 2.21; 95% CI 1.02 to 4.75; four trials, 5373 infants). One trial contributed over 70% of the participants to the analysis for this outcome; the trial authors suggested that the large number of severe congenital anomalies in the supplemented group (unlikely attributable to magnesium) and the deaths of two sets of twins (with birthweights < 750 g) in the supplemented group likely accounted for the increased risk of death observed, and thus this result should be interpreted with caution. Furthermore, when the deaths due to severe congenital abnormalities in this trial were excluded from the meta-analysis, no increased risk of neonatal death was seen for the magnesium supplemented group. Magnesium supplementation was associated with significantly fewer babies with an Apgar score less than seven at five minutes (RR 0.34; 95% CI 0.15 to 0.80; four trials, 1083 infants), with meconium-stained liquor (RR 0.79; 95% CI 0.63 to 0.99; one trial, 4082 infants), late fetal heart decelerations (RR 0.68; 95% CI 0.53 to 0.88; one trial, 4082 infants), and mild hypoxic-ischaemic encephalopathy (RR 0.38; 95% CI 0.15 to 0.98; one trial, 4082 infants). Women receiving magnesium were significantly less likely to require hospitalisation during pregnancy (RR 0.65, 95% CI 0.48 to 0.86; three trials, 1158 women).Of the 10 trials included in the review, only two were judged to be of high quality overall. When an analysis was restricted to these two trials none of the review's primary outcomes (perinatal mortality, small-for-gestational age, pre-eclampsia) were significantly different between the magnesium supplemented and control groups. AUTHORS' CONCLUSIONS: There is not enough high-quality evidence to show that dietary magnesium supplementation during pregnancy is beneficial.


Subject(s)
Dietary Supplements , Magnesium/administration & dosage , Pregnancy , Administration, Oral , Congenital Abnormalities/mortality , Female , Humans , Infant Mortality , Infant, Newborn , Magnesium/adverse effects , Pre-Eclampsia/prevention & control , Pregnancy Outcome , Pregnancy, High-Risk , Randomized Controlled Trials as Topic , Stillbirth/epidemiology
19.
Cochrane Database Syst Rev ; (2): CD001689, 2014 Feb 11.
Article in English | MEDLINE | ID: mdl-24519568

ABSTRACT

BACKGROUND: Venous thromboembolism (VTE), although rare, is a major cause of maternal mortality and morbidity, and methods of prophylaxis are therefore often used for women considered to be at risk. This may include women who have given birth by caesarean section, those with a personal or family history of VTE and women with inherited or acquired thrombophilias (conditions that predispose people to thrombosis). Many methods of prophylaxis carry risks of adverse effects, and as the risk of VTE is often low, it is possible that the benefits of thromboprophylaxis may be outweighed by harms. Guidelines for clinical practice have been based on expert opinion rather than high-quality evidence from randomised trials. OBJECTIVES: To assess the effects of thromboprophylaxis in women who are pregnant or have recently given birth and are at increased risk of VTE on the incidence of VTE and adverse effects of treatment. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (27 November 2013).  SELECTION CRITERIA: Randomised trials comparing one method of thromboprophylaxis with placebo or no treatment, and randomised trials comparing two (or more) methods of thromboprophylaxis. DATA COLLECTION AND ANALYSIS: At least two review authors assessed trial eligibility and quality and extracted the data. MAIN RESULTS: Nineteen trials, at an overall moderate risk of bias, met the inclusion criteria for the review. Only 16 trials, involving 2592 women, assessing a range of methods of thromboprophylaxis, contributed data to the review. Six trials compared methods of antenatal prophylaxis: heparin versus no treatment/placebo (two trials), and low molecular weight heparin (LMWH) versus unfractionated heparin (UFH) (four trials). Nine trials assessed prophylaxis after caesarean section: four compared heparin with placebo; three compared LMWH with UFH; one compared hydroxyethyl starch (HES) with UFH; and one compared five-day versus 10-day LMWH. One study examined prophylaxis with UFH in the postnatal period (including following vaginal births).For antenatal prophylaxis, none of the included trials reported on maternal mortality, and no differences were detected for the other primary outcomes of symptomatic thromboembolic events, symptomatic pulmonary embolism (PE) and symptomatic deep venous thrombosis (DVT) when LMWH or UFH was compared with no treatment/placebo or when LMWH was compared with UFH. The risk ratios (RR) for symptomatic thromboembolic events were: antenatal LMWH/UFH versus no heparin, RR 0.33; 95% confidence interval (CI) 0.04 to 2.99 (two trials, 56 women); and antenatal LMWH versus UFH, RR 0.47; 95% CI 0.09 to 2.49 (four trials, 404 women). No differences were shown when antenatal LMWH or UFH was compared with no treatment/placebo for any secondary outcomes. Antenatal LMWH was associated with fewer adverse effects sufficient to stop treatment (RR 0.07; 95% CI 0.01 to 0.54; two trials, 226 women), and fewer fetal losses (RR 0.47; 95% CI 0.23 to 0.95; three trials, 343 women) when compared with UFH. In two trials, antenatal LMWH compared with UFH was associated with fewer bleeding episodes (defined in one trial of 121 women as bruises > 1 inch (RR 0.18, 95% CI 0.09 to 0.36); and in one trial of 105 women as injection site haematomas of ≥ 2 cm, bleeding during delivery or other bleeding (RR 0.28; 95% CI 0.15 to 0.53)), however in a further trial of 117 women no difference between groups was shown for bleeding at delivery. The results for these secondary outcomes should be interpreted with caution, being derived from small trials that were not of high methodological quality.For post-caesarean/postnatal prophylaxis, only one trial comparing five-day versus 10-day LMWH after caesarean section reported on maternal mortality, observing no deaths. No differences were seen across any of the comparisons for the other primary outcomes (symptomatic thromboembolic events, symptomatic PE and symptomatic DVT). The RRs for symptomatic thromboembolic events were: post-caesarean LMWH/UFH versus no heparin, RR 1.30; 95% CI 0.39 to 4.27 (four trials, 840 women); post-caesarean LMWH versus UFH, RR 0.33; 95% CI 0.01 to 7.99 (three trials, 217 women); post-caesarean five-day versus 10-day LMWH, RR 0.36; 95% CI 0.01 to 8.78 (one trial, 646 women); postnatal UFH versus no heparin, RR 0.16; 95% CI 0.02 to 1.36 (one trial, 210 women). For prophylaxis after caesarean section, in one trial (of 580 women), women receiving UFH and physiotherapy were more likely to have bleeding complications ('complications hémorragiques') than women receiving physiotherapy alone (RR 5.03; 95% CI 2.49 to 10.18). In two additional trials, that compared LMWH with placebo, no difference between groups in bleeding episodes (major bleeding; major bruising; bleeding/bruising reported at discharge) were detected. No other differences in secondary outcomes were shown when LMWH was compared with UFH post-caesarean, nor when post-caesarean HES was compared with UFH, post-caesarean five-day LMWH was compared with 10-day LMWH, or when UFH was compared to no heparin postnatally. AUTHORS' CONCLUSIONS: There is insufficient evidence on which to base recommendations for thromboprophylaxis during pregnancy and the early postnatal period, with the small number of differences detected in this review being largely derived from trials that were not of high methodological quality. Large scale, high-quality randomised trials of currently used interventions are warranted.


Subject(s)
Pregnancy Complications, Hematologic/prevention & control , Puerperal Disorders/prevention & control , Venous Thrombosis/prevention & control , Female , Humans , Pregnancy , Randomized Controlled Trials as Topic
20.
Dev Biol ; 385(1): 13-22, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-24184636

ABSTRACT

In the developing brain, the production of neurons from multipotent precursors must be carefully regulated in order to generate the appropriate numbers of various differentiated neuronal types. Inductive signals from extrinsic elements such as growth factors need to be integrated with timely expression of intrinsic elements such as transcription factors that define the competence of the cell. The transcriptional Mediator complex offers a mechanism to coordinate the timing and levels of intrinsic and extrinsic influences by acting as a rapid molecular switch for transcription of poised RNA pol II. The epithalamus is a highly conserved region of the vertebrate brain that differentiates early and rapidly in the zebrafish. It includes the pineal and parapineal organs and the habenular nuclei. Mutation of the Mediator complex subunit Med12 impairs the specification of habenular and parapineal neurons and causes a loss of differentiation in pineal neurons and photoreceptors. Although FGF ligands and transcription factors for parapineal and photoreceptor development are still expressed in the pineal complex of med12 mutants, FGF signaling is impaired and transcription factor expression is reduced and/or delayed. We find that the timely expression of one of these transcription factors, tbx2b, is controlled by Med12 and is vital for parapineal specification. We propose that the Mediator complex is responsible for subtle but significant changes in transcriptional timing and amplitude that are essential for coordinating the development of neurons in the epithalamus.


Subject(s)
Epithalamus/embryology , Mediator Complex/metabolism , Neural Stem Cells/metabolism , T-Box Domain Proteins/biosynthesis , Zebrafish Proteins/biosynthesis , Zebrafish Proteins/metabolism , Zebrafish/embryology , Animals , Cell Differentiation , Epithalamus/abnormalities , Fibroblast Growth Factors/metabolism , Gene Expression Regulation, Developmental , Habenula/abnormalities , Habenula/embryology , Mediator Complex/genetics , Pineal Gland/abnormalities , Pineal Gland/embryology , Retinal Cone Photoreceptor Cells/metabolism , Retinal Rod Photoreceptor Cells/metabolism , Signal Transduction , Transcription, Genetic , Transcriptional Activation , Zebrafish/genetics , Zebrafish/metabolism , Zebrafish Proteins/genetics
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