ORCID Profile
0000-0003-1546-752X
Current Organisation
The University of Auckland
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Publisher: Elsevier BV
Date: 10-2011
DOI: 10.1016/J.GENE.2011.06.028
Abstract: Pseudotrisomy 13 syndrome is characterised by holoprosencephaly with or without polydactyly, but with a normal karyotype. The genetic cause of this syndrome remains unclear, but it is thought to be autosomal recessive. In order to identify possible candidate genes, we identified regions of homozygosity in the DNA of an affected foetus, which was the seventh pregnancy of a healthy non-consanguineous Cook Island Maori couple this ethnic group derives from a small founder population. Several large regions of homozygosity were identified using a high density array. We excluded two candidate genes that lay within these regions, and suggest that Pseudotrisomy 13 syndrome might not be monogenic and that a larger cohort of patients should be analysed using high density dosage/SNP arrays as well as whole exome sequencing in order to clarify the genetic underpinning of this rare syndrome.
Publisher: Elsevier BV
Date: 2012
Publisher: MDPI AG
Date: 21-09-2023
Publisher: SAGE Publications
Date: 30-09-2020
Abstract: To determine the level of quality of life (QoL) in children with cleft lip and/or palate (CL/P) and whether this differs by cleft phenotype. A cohort of children with CL/P born in New Zealand. A nationwide study of children born with CL/P and having primary surgery in New Zealand. Children with CL/P and their families (n = 397) who attended a cleft clinic between October 1, 2014, and September 30, 2017, and agreed to complete questionnaires on QoL. Primary outcomes were QoL from the PedsQL 4.0 core generic questionnaires and the PedsQL 2.0 Family impact scale. Children with CL/P in New Zealand generally have a high QoL as assessed by the PedsQL. The impact of cleft phenotype had limited effects on the child, however there were significant impacts on parents and families. We found that the family impact scale differed by cleft phenotype with those with CL having the highest QoL and those with cleft palate the lowest, and this was consistent across QoL subscales. Quality of life improved as a whole by age, particularly in physical and cognitive functioning, as well as in the ability to undertake family activities. Children with CL/P have generally good levels of QoL in New Zealand, however cleft phenotype impacts on the level, with the lowest levels in those with cleft palate. Psychological support of children with cleft and their families should be an integral part of cleft care.
Publisher: Wiley
Date: 29-03-2019
DOI: 10.1111/OCR.12310
Abstract: To (a) assess nasolabial outcomes across four main cleft subgroups, (b) assess agreement using a categorical and a continuous scoring measure and (c) compare outcomes to international studies. Analysis of 470 images of which 218 was unilateral cleft lip and palate (UCLP), 128 unilateral cleft lip (UCL), 90 bilateral cleft lip and palate (BCLP) and 34 bilateral cleft lip (BCL). Images were taken around five (n = 279) and eight-ten (n = 191) years of age. Cropped images were assessed using the Asher-McDade (AM) and a 100 mm visual analogue scale (VAS) by a panel of six raters. Scoring was undertaken for vermillion border and nasal form, symmetry and profile. Analysis was undertaken for each subscore, a total score with sensitivity analysis using a total score based on the subscores for each patient. AM intra- and inter-rater reliability was assessed using weighted kappa and for the VAS components reliability was assessed using Pearson correlation. The AM intra-rater reliability was moderate/substantial, whilst inter-rater reliability was fair. The VAS intra-rater correlations were high, and inter-rater correlations were moderate. Better outcomes were found with cleft lip (CL) vs cleft lip and palate (CLP). No differences were found for sex, ethnicity, age and cleft laterality (unilateral). The AM found no difference between unilateral or bilateral. The VAS found bilateral scored worse than unilateral for both CL and CLP. The nasolabial outcomes differ by cleft type. The correlation was relatively high for the VAS whilst the AM had relatively poor reliability.
Publisher: SAGE Publications
Date: 21-10-2021
DOI: 10.1177/10556656211044939
Abstract: To assess speech outcomes at five and ten years of age in a nationwide study of children with orofacial cleft. Prospective study. Children born with orofacial cleft and having primary surgery in New Zealand. Speech s les were available for 151 five-year-old, and 163 ten-year-old children. Intelligibility, Acceptability, Velopharyngeal function, Hypernasality, Hyponasality, severity of airflow evaluated by perceptual speech assessment (using the standardised Rhinocleft assessment), and overall assessment of requirement for clinical intervention. A large proportion of five-year-old children had speech that was considered to be not completely intelligible, was not acceptable, and had inadequate velopharyngeal function. The noted deficiencies led to a clinical judgement that further speech and/or surgical intervention was required in 85% with cleft lip and palate, 65% with cleft palate and 26% with cleft lip. The proportion of children with poor speech outcomes in the ten-year-old children was lower, though of clinical importance, further intervention required for 25% with CLP, 15% with CP and 3% with CL. The number of sound production errors in both age groups followed the same pattern with fewest in those with CL and most in those with CLP. A significant proportion of children with orofacial cleft were found to have poor speech outcomes requiring further treatment. The outcomes are poor compared to centres reported in the UK and Scandinavia. New Zealand requires a review of the current services for in iduals born with cleft to improve speech outcomes and interdisciplinary care.
Publisher: Elsevier BV
Date: 02-2014
DOI: 10.1016/J.PLACENTA.2013.10.014
Abstract: Ask where the maternofetal interface is and placental biologists will tell you, the syncytiotrophoblast and extravillous cytotrophoblasts. While correct, this is not full extent of the maternofetal interface. Trophoblast debris that is extruded into the maternal blood in all pregnancies expands the maternofetal interface to sites remote from the uterus. Trophoblast debris ranges from multinucleated syncytial nuclear aggregates to subcellular micro- and nano-vesicles. The origins of trophoblast debris are not clear. Some propose trophoblast debris is the end of the life-cycle of the trophoblast and that it results from an apoptosis-like cell death, but this is not universally accepted. Knowing whether trophoblast debris results from an apoptosis-like cell death is important because the nature of cell death that produced trophoblast debris will influence the maternal responses to it. Trophoblast debris is challenging to isolate from maternal blood making it difficult to study. However, by culturing placental explants in Netwells™ we can readily harvest trophoblast debris from beneath the Netwells™ which is very similar to debris that has been isolated from pregnant women. We have found that trophoblast debris from normal placentae shows markers of apoptosis and is phagocytosed by macrophages or endothelial cells, producing a tolerant phenotype in the phagocyte. Whereas, when we culture normal placental explants with factors such as antiphospholipid antibodies (a strong maternal risk factor for preecl sia), or IL-6 (which is found at increased levels in the sera of preecl tic women), the death process in the syncytiotrophoblast changes, such that the trophoblast debris becomes more necrotic. Phagocytosis of this necrotic debris leads to activation of endothelial cells. Trophoblast debris greatly expands the maternofetal interface and the nature of that debris is likely to strongly influence the responses of the maternal vascular and immune systems to the debris.
Publisher: SAGE Publications
Date: 16-12-2020
Abstract: To describe (1) oral health related quality of life (OHRQoL) for children with orofacial cleft (OFC) in New Zealand and (2) assess any differences in OHRQoL by sex, ethnicity, and cleft phenotype using the 16 item (and 8 item subset) of the Child Perception Questionnaire (CPQ) and Parent version (P-CPQ). Prospective cross-sectional nationwide study. Children with OFC and their parents completed the 16-item CPQ or the Parent CPQ, respectively, when attending cleft clinic appointments between January 2015 and December 2017. Overall, 174 children (mean age 10.4 ± 1.2 years) and their parents (n = 181) completed the CPQ or P-CPQ. In multivariable analysis, neither the CPQ nor P-CPQ 16-item or 8-item subset showed significant differences in OHRQoL total score with cleft phenotype. Children with cleft lip and palate (CLP) had higher (worse) well-being scores than those with cleft palate alone (CP) on the P-CPQ. Pacific Island children had consistently higher scores across both CPQ and P-CPQ, total and subscales. Significant differences in OHRQoL among children with OFC were found for the well-being domain for children with CLP as reported by P-CPQ, but the symptom domain and total score showed no differences. Poorer scores were reported for children of Pacific Island descent using both questionnaires. The study findings indicate that children with OFC in New Zealand are a group who experience worse OHRQoL when referenced to normative non-OFC data. Further investigations are required to establish greater insight into specific factors influencing OHRQoL.
Publisher: Wiley
Date: 18-01-2021
DOI: 10.1113/JP280569
Abstract: Maternal supine sleep position in late pregnancy is associated with an increased risk of stillbirth. Maternal supine position in late pregnancy reduces maternal cardiac output and uterine blood flow. Using MRI, this study shows that compared to the left lateral position, maternal supine position in late pregnancy is associated with reduced utero‐placental blood flow and oxygen transfer across the placenta with an average 6.2% reduction in oxygen delivery to the fetus and an average 11% reduction in fetal umbilical venous blood flow. Maternal sleep position in late gestation is associated with an increased risk of stillbirth, though the pathophysiological reasons for this are unclear. Studies using magnetic resonance imaging (MRI) have shown that compared with lateral positions, lying supine causes a reduction in cardiac output, reduced abdominal aortic blood flow and reduced vena caval flow which is only partially compensated for by increased flow in the azygos venous system. Using functional MRI techniques, including an acquisition termed diffusion–relaxation combined imaging of the placenta (DECIDE), which combines diffusion weighted imaging and T2 relaxometry, blood flow and oxygen transfer were estimated in the maternal, fetal and placental compartments when subjects were scanned both supine and in left lateral positions. In late gestation pregnancy, lying supine caused a 23.7% ( P 0.0001) reduction in total internal iliac arterial blood flow to the uterus. In addition, lying in the supine position caused a 6.2% ( P = 0.038) reduction in oxygen movement across the placenta. The reductions in oxygen transfer to the fetus, termed delivery flux, of 11.2% ( P = 0.0597) and in fetal oxygen saturation of 4.4% ( P = 0.0793) did not reach statistical significance. It is concluded that even in healthy late gestation pregnancy, maternal position significantly affects oxygen transfer across the placenta and may in part provide an explanation for late stillbirth in vulnerable fetuses.
Publisher: Springer Science and Business Media LLC
Date: 28-03-2015
Publisher: Wiley
Date: 19-07-2023
DOI: 10.1113/JP284269
Abstract: Fetal growth restriction (FGR) and maternal supine going‐to‐sleep position are both risk factors for late stillbirth. This study aimed to use magnetic resonance imaging (MRI) to quantify the effect of maternal supine position on maternal‐placental and fetoplacental blood flow, placental oxygen transfer and fetal oxygenation in FGR and healthy pregnancies. Twelve women with FGR and 27 women with healthy pregnancies at 34–38 weeks’ gestation underwent MRI in both left lateral and supine positions. Phase‐contrast MRI and a functional MRI technique (DECIDE) were used to measure blood flow in the maternal internal iliac arteries (IIAs) and umbilical vein (UV), placental oxygen transfer (placental flux), fetal oxygen saturation (FO 2 ), and fetal oxygen delivery (delivery flux). The presence of FGR, compared to healthy pregnancies, was associated with a 7.8% lower FO 2 ( P = 0.02), reduced placental flux, and reduced delivery flux. Maternal supine positioning caused a 3.8% reduction in FO 2 ( P = 0.001), and significant reductions in total IIA flow, placental flux, UV flow and delivery flux compared to maternal left lateral position. The effect of maternal supine position on fetal oxygen delivery was independent of FGR pregnancy, meaning that supine positioning has an additive effect of reducing fetal oxygenation further in women with FGR, compared to women with appropriately grown for age pregnancies. Meanwhile, the effect of maternal supine positioning on placental oxygen transfer was not independent of the effect of FGR. Therefore, growth‐restricted fetuses, which are chronically hypoxaemic, experience a relatively greater decline in oxygen transfer when mothers lie supine in late gestation compared to appropriately growing fetuses. image Fetal growth restriction (FGR) is the most common risk factor associated with stillbirth, and early recognition and timely delivery is vital to reduce this risk. Maternal supine going‐to‐sleep position is found to increase the risk of late stillbirth but when combined with having a FGR pregnancy, maternal supine position leads to 15 times greater odds of stillbirth compared to supine sleeping with appropriately grown for age (AGA) pregnancies. Using MRI, this study quantifies the chronic hypoxaemia experienced by growth‐restricted fetuses due to 13.5% lower placental oxygen transfer and 26% lower fetal oxygen delivery compared to AGA fetuses. With maternal supine positioning, there is a 23% reduction in maternal‐placental blood flow and a further 14% reduction in fetal oxygen delivery for both FGR and AGA pregnancies, but this effect is proportionally greater for growth‐restricted fetuses. This knowledge emphasises the importance of avoiding supine positioning in late pregnancy, particularly for vulnerable FGR pregnancies.
Publisher: Wiley
Date: 06-2002
DOI: 10.1046/J.1440-1754.2002.00783.X
Abstract: To determine in New Zealand infants the attack rates, risk factors, preventive policies, strain serotype and antibiotic susceptibilities of early-onset neonatal group B streptococcus (GBS) infection. A 2-year prospective active surveillance study was conducted in New Zealand's 19 neonatal units. Cases had to present within 48 h of delivery, be unwell, possess abnormal haematological indices and have GBS isolated from sterile sites. Of the 112 402 infants born in New Zealand during 1998-1999, 56 had early-onset GBS infection, an attack rate of 0.5 per 1000 live births (95% confidence interval [CI] 0.38, 0.65). Seven had meningitis and there was one death (case fatality rate of 1.8% upper 95% CI 9.5%). Univariate analysis identified young maternal age, parity, preterm labour, prolonged membrane rupture, maternal fever and assisted delivery as risk factors. Preventive policies for GBS were reported by 14 (74%) obstetric centres associated with neonatal units. Of the 56 cases, five (9%) were born to mothers receiving intrapartum antibiotics, 32 (57%) had mothers with risk factors but were not treated with antibiotics, and 19 (34%) were born to mothers without identifiable risk factors for GBS prevention. Serotypes Ia and III predominated, while two isolates were resistant to erythromycin and/or clindamycin. Rates of early-onset GBS infection are similar to other countries following the introduction of prevention policies. Further reductions are possible with full implementation of these guidelines. Meanwhile, emergence of antibiotic resistance complicates the management of women with penicillin allergy. Vaccine development therefore remains a priority.
Publisher: SAGE Publications
Date: 25-11-2020
Abstract: To determine whether children with an orofacial cleft have higher levels of behavioral problems than the general population and whether this differs by cleft phenotype. A cohort of children with cleft lip and/or palate (CL/P) born in New Zealand from January 1, 2000. Cleft clinics in New Zealand participating in a larger outcomes study between 2014 and 2017. Children (N = 378) aged 5 to 12 years of age and their parents. The Strengths and Difficulties Questionnaire (SDQ) and Pediatric Quality of Life Inventory (PedsQL) Generic Core Scales 4.0 and Family Impact Module 2.0. Compared to standardized norms, children with a cleft had higher than expected (defined as 20%) levels of abnormal/borderline SDQ scores for conduct problems (27.4%, P = .0003) and peer relationship problems (31.6%, P .0001) but lower than expected levels of problems with pro-social skills (6.3%, P .0001). There were no significant differences by age-group and or cleft phenotype other than an increased risk of hyperactivity in children with CP compared to children with CL. Total difficulties SDQ scores had moderate correlations with the PedsQL. While over 90% of children with CL/P had normal prosocial skills, they may not be easily accepted by their peers which may result in behavioral problems. These concerns were moderately related to lower quality of life. Support for establishment and maintenance of peer relationships is important to address externalizing and peer difficulties in children with CL/P. Community knowledge and understanding of CL/P needs to continue to be promoted.
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