Jessica L. Broadbent

Epidemiologic associations with cerebral palsy

OBJECTIVE: To estimate epidemiologic risk factors for cerebral palsy. METHODS: Data were collected by linkage to state-based perinatal repositories and cerebral palsy registers and using a maternal questionnaire. The cohort included 587 individuals with cerebral palsy and 1,154 non–cerebral palsy controls. RESULTS: The following factors were associated with cerebral palsy: recorded maternal infection during pregnancy (41.4% patients compared with 31.3% controls; odds ratio [OR] 1.55, 95% confidence interval 1.26–1.91), small for gestational age ([birth weight less than third customized centile] 43.9% patients compared with 6.3% controls; OR 11.75, 6.25–22.08), gestational age less than 32 weeks (29.3% patients compared with 0.7% controls; OR 59.20, 28.87–121.38), multiple birth (OR 6.62, 4.00–10.95), a relative with cerebral palsy (OR 1.61, 1.12–2.32), breech position (13.7% patients compared with 6.0% controls; OR 2.48, 1.76–3.49), bleeding at any time in pregnancy (29.3% patients compared with 16.9% controls; OR 2.04, 1.61–2.58), male sex (58.8% patients compared with 45.8% controls; OR 1.68, 1.38–2.06), multiple miscarriage (7.7% patients compared with 3.5% controls; OR 2.30, 1.38–3.82), smoking (14.0% patients compared with 10.6% controls; OR 1.37, 1.02–1.85), and illicit drug use (3.3% patients compared with 1.5% controls; OR 2.22, 1.14–4.30). Factors not associated with cerebral palsy were “disappearing twin,” diabetes, maternal body mass index, hypertension, alcohol consumption, anemia, maternal hypothyroidism, forceps or vacuum delivery, and maternal age. CONCLUSION: Preterm birth, intrauterine growth restriction, perinatal infection, and multiple birth present the largest risks for a cerebral palsy outcome. Reassuringly, upper respiratory tract and gastrointestinal infections during pregnancy were not associated with cerebral palsy. LEVEL OF EVIDENCE: II

Genistein inhibits growth of B16 melanoma cells in vivo and in vitro and promotes differentiation in vitro

Consumption of soy products has been linked to a reduced mortality and morbidity from a number of cancers. Genistein, one of the principal soy isoflavones, has been shown to inhibit the growth of a number of tumour cell lines in vitro; however, a role of genistein in retarding tumour growth in vivo is less well documented. In this study, in addition to examining the effects of genistein on the growth of murine B16 melanoma cells in vitro, we have examined the effects of feeding a genistein‐rich diet on s.c. growth of these tumour cells in mice. In vitro, the melanoma cells showed an increase in sensitivity to genistein with increasing time of exposure, culminating in a 50% growth inhibition (IC50) at 12.5 μM after 7 days. Genistein at 25 μM induced micronucleus formation after 24 hr and at concentrations as low as 2.5 μM induced morphological changes indicative of differentiation. Growth of solid tumours implanted into female C57BL/6J mice was inhibited by 50% when mice were fed genistein for 1 week before and for 1 week after inoculation with B16 melanoma cells. Plasma genistein concentrations at the time of tumour removal were 1.1 μM, which is similar to levels reported in humans consuming diets high in soybeans or soybean products, while control animals had no detectable genistein in plasma. Our results provide additional in vivo evidence suggesting that genistein retards the growth of implanted tumours, adding further to studies suggesting that this isoflavonoid is a biologically active component of soy foods. Int. J. Cancer 72:860–864, 1997.

Whole-exome sequencing points to considerable genetic heterogeneity of cerebral palsy

Cerebral palsy (CP) is a common, clinically heterogeneous group of disorders affecting movement and posture. Its prevalence has changed little in 50 years and the causes remain largely unknown. The genetic contribution to CP causation has been predicted to be ~2%. We performed whole-exome sequencing of 183 cases with CP including both parents (98 cases) or one parent (67 cases) and 18 singleton cases (no parental DNA). We identified and validated 61 de novo protein-altering variants in 43 out of 98 (44%) case-parent trios. Initial prioritization of variants for causality was by mutation type, whether they were known or predicted to be deleterious and whether they occurred in known disease genes whose clinical spectrum overlaps CP. Further, prioritization used two multidimensional frameworks—the Residual Variation Intolerance Score and the Combined Annotation-dependent Depletion score. Ten de novo mutations in three previously identified disease genes (TUBA1A (n=2), SCN8A (n=1) and KDM5C (n=1)) and in six novel candidate CP genes (AGAP1, JHDM1D, MAST1, NAA35, RFX2 and WIPI2) were predicted to be potentially pathogenic for CP. In addition, we identified four predicted pathogenic, hemizygous variants on chromosome X in two known disease genes, L1CAM and PAK3, and in two novel candidate CP genes, CD99L2 and TENM1. In total, 14% of CP cases, by strict criteria, had a potentially disease-causing gene variant. Half were in novel genes. The genetic heterogeneity highlights the complexity of the genetic contribution to CP. Function and pathway studies are required to establish the causative role of these putative pathogenic CP genes.

Continuing decline in hormone therapy use : population trends over 17 years

Objective To describe the prevalence of menopausal hormone therapy (HT) in 2008 and trends over the last 17 years in an Australian population. Methods Data were obtained from nine representative population face-to-face interview surveys of the South Australian population from 1991 to 2008. The surveys used consistent method and quality control procedures. In 2008, demographic data, HT use and eight dimensions of health, using the SF-36 health survey questionnaire, were measured. Participants Over 3000 South Australian adults were interviewed in their own home by trained health interviewers in each of the surveys; in the 2008 survey, 1555 women participated, of whom 953 were over age 40. Results After a peak in use in the 2000 survey, HT use fell from 2003 and has continued to decline in 2008. In 2008, current use over age 50 of registered conventional HT products is now 11.8%, with a further 4.0% using non-registered alternative ‘hormonal’ products. Current HT use is highest between the ages of 50 and 59 years, where 13.4% use conventional HT and 7.7% use unconventional alternative hormones. Use of these unregistered hormonal products was rare in previous surveys. Median and mean length of conventional HT use were 10.0 and 10.5 years, respectively. HT users continued to have a demographic profile similar to those in previous surveys, i.e. they were better educated, employed, partnered, had a higher income and were less inclined to use complementary and alternative medicines. Conclusions There has been a continuing decline in both the overall prevalence and length of use of conventional HT from 2003, probably in association with negative media about HT. Of medical concern is that about one-quarter of women using HT around menopause now chooses unregistered hormonal mixtures that are untested for long-term safety and efficacy.

Inadequate compliance with periconceptional folic acid supplementation in South Australia

Background:  Despite recommendations for women to take folic acid supplements, there has been little reduction in the number of neural tube defect cases occurring each year.

Fetal and Maternal Candidate Single Nucleotide Polymorphism Associations With Cerebral Palsy: A Case-Control Study

OBJECTIVE: Previous studies have suggested associations between certain genetic variants and susceptibility to cerebral palsy (CP). This study was designed to assess established and novel maternal and child genetic and epidemiologic risk factors for CP along with their interactions. METHODS: DNA from 587 case and 1154 control mother-child pairs was analyzed. A panel of 35 candidate single nucleotide polymorphisms (SNPs) were examined and included SNPs in genes associated with (1) thrombophilia, (2) inflammation, and (3) risk factors for CP (eg, preterm birth). Comparisons were specified a priori and made by using a χ2 test. RESULTS: There were 40 fetal and 28 maternal associations with CP when analyzed by CP subtype, gestational age, genotypes of apolipoprotein E, and haplotypes of mannose-binding-lectin. After Bonferroni correction for multiple testing, no fetal or maternal candidate SNP was associated with CP or its subtypes. Only fetal carriage of prothrombin gene mutation remained marginally associated with hemiplegia in term infants born to mothers with a reported infection during pregnancy. Odds ratio directions of fetal SNP associations were compared with previously reported studies and confirmed no trend toward association. CONCLUSIONS: Except for the prothrombin gene mutation, individual maternal and fetal SNPs in our candidate panel were not found to be associated with CP outcome. Past reported SNP associations with CP were not confirmed, possibly reflecting type I error from small numbers and multiple testing in the original reports.

The Australian cerebral palsy research study - Protocol for a national collaborative study investigating genomic and clinical associations with cerebral palsy

Aim:  Previous studies have proposed a link between the presence of specific single nucleotide polymorphisms (SNPs) and cerebral palsy and the majority of these associations remain to be confirmed or rejected by prospective studies with sufficient statistical power. Prior studies have also given little attention to the interaction of genomic characteristics and clinical risk factors.

Genetic and clinical contributions to cerebral palsy: A multi-variable analysis

This study aims to examine single nucleotide polymorphism (SNP) associations with cerebral palsy in a multi‐variable analysis adjusting for potential clinical confounders and to assess SNP–SNP and SNP–maternal infection interactions as contributors to cerebral palsy.

Analysis of 182 cerebral palsy transcriptomes points to dysregulation of trophic signalling pathways and overlap with autism

Cerebral palsy (CP) is the most common motor disability of childhood. It is characterised by permanent, non-progressive but not unchanging problems with movement, posture and motor function, with a highly heterogeneous clinical spectrum and frequent neurodevelopmental comorbidities. The aetiology of CP is poorly understood, despite recent reports of a genetic contribution in some cases. Here we demonstrate transcriptional dysregulation of trophic signalling pathways in patient-derived cell lines from an unselected cohort of 182 CP-affected individuals using both differential expression analysis and weighted gene co-expression network analysis (WGCNA). We also show that genes differentially expressed in CP, as well as network modules significantly correlated with CP status, are enriched for genes associated with ASD. Combining transcriptome and whole exome sequencing (WES) data for this CP cohort likely resolves an additional 5% of cases separated to the 14% we have previously reported as resolved by WES. Collectively, these results support a convergent molecular abnormality in CP and ASD.