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B Petterson

Publications and source records attributed to B Petterson.

At least 19 recordsLinked to original sources

Survival of infants born with Down's syndrome: 1980-96.

The improved life expectancy of people with Down's syndrome as a result of the greater availability of surgery and advances in medical care has been widely documented. However, there has been no evaluation of survival in the Australian Down's syndrome population since the 1980s. This study aimed to evaluate the changes in survival from birth in cases of Down's syndrome notified to the Birth Defects Registry in Western Australia. Babies born with Down's syndrome between 1980 and 1996 (inclusive) and registered with the Birth Defects Registry were studied. Survival status was obtained in several ways. Cases were stratified into three cohorts for comparison. Survival curves were constructed using the methods of Kaplan and Meier. For infants born during 1980-96, survival to 1 year is now > 91%, and 85% can expect to survive until the age of 10 years. Although survival in those with heart disease showed improvement over the period studied, overall this was still a strong predictor of mortality. Survival in Aboriginal children with Down's syndrome was significantly poorer than in non-Aboriginal children, mirroring the pattern in the general population. Mortality was greater in females and in those with a low birthweight. There was no statistically significant difference in the survival between those born in metropolitan and in rural areas. There has been a considerable improvement in survival of infants born with Down's syndrome in Western Australia. This improvement is similar to findings in recent international studies. The difference in survival between Aboriginal and non-Aboriginal children is particularly disturbing. These findings are useful for both clinicians and families who need to plan for the long-term care of these children.

Adult↗

Intellectual disability in Western Australia.

OBJECTIVE: To investigate the prevalence of intellectual disability in Western Australia (WA), its causes, prevention, and trends over time. METHODOLOGY: Data from an administrative database of intellectual disability in WA were used to report on the trends in intellectual disability in childhood. RESULTS: The prevalence of intellectual disability was 8.3 per 1000 live births in 1980-90. For half the cases, there was no known cause for the intellectual disability. Down syndrome accounted for 14 to 15% of all cases. Since the introduction of newborn screening, no WA-born child participating in the screening program has been diagnosed with intellectual disability as a result of either phenylketonuria or congenital hypothyroidism. The rate of autism spectrum disorders rose from three to six per 10 000 in the 1980-83 WA birth cohort to 10-13 per 10 000 for the 1989-92 cohort. CONCLUSIONS: Recent linkage of this administrative database to the WA Maternal and Child Health Research Data Base provides a unique opportunity for more detailed investigation of intellectual disability and its risk factors in a large, well-ascertained population of children.

Autistic Disorder↗

Medical aspects of school-aged children with Down syndrome.

Current and comprehensive information about the medical issues affecting children with Down syndrome (DS) is of value in counselling parents who are considering prenatal diagnosis and in planning services for people with DS as they age, especially given the continued improvements in their survival. Parents of school-aged children (mean age 11.37 years, 57.3% male, 42.7% female) with DS were identified by linking registers from the Disability Services Commission and the Birth Defects Registry. Less than half the children had cardiac and bowel conditions. More than half had ear conditions and more than three quarters had eye conditions. Ear, nose, and throat professionals were the specialists seen most often and the rate of tympanostomy tube insertion was nearly 17 times that of the general childhood population. Children with DS were over five times more likely to wear glasses than other children. These findings suggest that chronic, non life-threatening conditions impose a burden on families but do not threaten quality of life.

Child↗

A DNA probe for the detection and identification of Bacillus sporothermodurans using the 16S-23S rDNA spacer region and phylogenetic analysis of some field isolates of Bacillus which form highly heat resistant spores.

The spacer regions between the 16S and 23S rRNA genes (spacer regions 1) of Bacillus sporothermodurans were PCR-amplified, cloned and sequenced. Six unique spacer sequences in four size classes were recovered from two strains, rrnA (about 190 bp), rrnB (about 303 bp), rrnC (355 bp) and rrnD (554 bp). rrnD contained two tRNA genes which were deciphered as tRNA(ala) and tRNA(ile) separated from each other by 13 nucleotides. The primary structures of the tRNA molecules clearly resembled those found in Bacillus subtilis; the tRNA(ala) genes were identical and the tRNA(ile) genes were 95% similar. The mixed rrnA and rrnB spacers when PCR-amplified from chromosomal DNA were effective as a hybridization probe for identification of B. sporothermodurans strains. However, high background signals with DNA from some other bacilli were encountered. A more discriminating probe was prepared from the cloned rrnB spacer region. Of eight aerobic, endospore-forming bacteria isolated from silage following heat enrichment, one was identified as B. sporothermodurans using the probe and its identity was confirmed from partial 16S rDNA analysis (phylotyping). This indicated that contamination in milk and dairies by B. sporothermodurans could originate from cattle feeds such as silage. Of the other seven silage strains, only two were identified conclusively by phylotyping and three represented probable new species. The latter three strains were subjected to phylogenetic analysis using almost complete 16S rDNA sequences. Branch lengths, bootstrap percentage values, and 16S rDNA similarity to other Bacillus species suggested that these isolates are likely to constitute new species within the genus Bacillus.

Animals↗

Adverse outcome after multiple pregnancy.

There is increasing interest in the outcomes of multiple pregnancies as their numbers rise, mainly owing to advances in fertility-enhancing techniques. In addition, the numbers of multiple births surviving the perinatal period is increasing with the increasing survival of very tiny babies. In order to investigate these outcomes or to evaluate procedures that may improve them, it is important to consider a number of methodological issues that affect the comparability of data both between and within populations. How a birth and a multiple birth are defined, data sources, whether multiple pregnancies or individual births are being counted and the identification of multiple gestations by zygosity and chorionicity will all affect the reported outcome rates. In light of this, perinatal mortality and neurodevelopmental disabilities are examined as adverse outcomes of multiple pregnancies.

Abortion, Spontaneous↗

What constitutes cerebral palsy?

Cerebral palsy (CP) is a term of convenience applied to a group of motor disorders of central origin defined by clinical description. It is not a diagnosis in that its application infers nothing about pathology, aetiology, or prognosis. It is an umbrella term covering a wide range of cerebral disorders which result in childhood motor impairment. The precise inclusion criteria vary with the objectives for using the term. For meaningful comparison of rates of CP, as performed by and between CP registers, it is important that the rates should be generated using the same criteria. As generally understood there must be motor impairment, and this impairment must stem from a malfunction of the brain (rather than spinal cord or muscles). Furthermore, the brain malfunction must be non-progressive and it must be manifest early in life. For the purposes of comparisons of rates across time even when the condition meets all the above criteria, it must not historically have been excluded from the category of CP. This paper addresses the problem of standardizing the inclusion criteria for selecting people included on CP registers with particular reference to this last criterion.

Cerebral Palsy↗

Doxorubicin-melphalan with and without cisplatin in advanced ovarian cancer--ten-year survival results from a prospective randomized study by the Swedish Cooperative Ovarian Cancer Study Group.

In a controlled prospective randomized study the regimen doxorubicin (A) 40 mg/m2 + melphalan (M) 0.4 mg/kg was compared with A + M + cisplatin (C) 50 mg/m2 given every four weeks in advanced ovarian cancer, FIGO stage III or IV and with serous or anaplastic histology. From 1981 to 1983, 300 patients entered the study and 295 patients were evaluable for response, toxicity and long-term survival. All patients were followed for at least 10 years. The majority of patients had large residual tumours >2 cm. Patients treated with MAC had a higher response rate compared with patients treated with MA (76% vs. 50%, p < 0.01) and treatment with MAC resulted in significantly more pathological complete responders than MA. There was a significant difference in median duration of response (19 months vs. 13 months, p < 0.006) and in median survival time (26 months vs. 19 months, p = 0.05). After 5- and 10 years a significant difference in progression-free and overall survival was found. The independent prognostic factors in this study were residual tumour after primary surgery, treatment with MAC, tumour grade, ascites, and stage. Objective and subjective side effects were significantly worse with MAC, although tolerable. In conclusion, this study shows that incorporating C into MA improves the duration of progression-free survival and overall survival in women with incompletely resected Stage III or Stage IV ovarian epithelial cancer. A 5- and 10-year survival of 25% and 18%, respectively, is impressive.

Adolescent↗

Antenatal antecedents of moderate and severe cerebral palsy.

Aetiological relationships between cerebral palsy, preterm birth, small-for-gestational-age (SGA) birth and selected feto-maternal factors were investigated in a case-control study of all moderate and severe cerebral palsy cases born in Western Australia between 1980 and 1986 (n = 215). Cases were individually matched to three controls of the same gender and plurality born in the same year. Two of the controls were matched to the index cases for gestational age, one of which was also matched for birthweight. Pre-eclampsia and urinary tract infections were not significantly associated with cerebral palsy. The significant association of antepartum haemorrhage with cerebral palsy was accounted for by its associations with preterm birth. Congenital malformations and non-cerebral palsy neurological disorder were significantly associated with cerebral palsy; these associations were only partially accounted for by adjusting for preterm birth and small-for-gestational-age birth. This study shows that some of the risk of cerebral palsy associated with the antenatal antecedents of some common feto-maternal factors is mediated through preterm birth, confirming the importance of interrelationships between antenatal antecedents in the aetiology of some cerebral palsy. Perinatal and post-neonatal causes now account for only around 20% of all cerebral palsy. Future reductions in cerebral palsy incidence may therefore depend on acquiring greater knowledge of inter-relationships between antenatal antecedents.

Case-Control Studies↗

Augmentation cystoplasty after cesarean hysterectomy for placenta previa-percreta.

We report a case of a 38-year old woman with placenta previa-percreta and urinary bladder invasion. Resection of the bladder wall during cesarean hysterectomy was complicated by a postoperative vesico-vaginal fistula and small-capacity bladder. A reconstructive augmentation cystoplasty utilizing the ileum was successful in improving the bladder capacity. To our knowledge, this is the first report of a placenta previa-percreta with bladder wall invasion which required reconstructive augmentation cystoplasty after cesarean hysterectomy. The obstetrician-gynecologist should be aware of reports of complications related to augmentation procedures, including late malignancy which may develop in the bowel segment used for cystoplasty.

Adult↗

Family patterns of gestational age at delivery and growth in utero in moderate and severe cerebral palsy.

The relation of familial factors to the aetiology of cerebral palsy was assessed in a case-control study of all moderate and severe cases born in Western Australia between 1980 and 1986. The data did not suggest recurrence of cerebral palsy, congenital malformations or reproductive loss in cerebral palsy families. Preterm and small-for-gestational-age birth recurred within both case and control families. Cases and controls did not differ significantly from their siblings in measures of intra-uterine growth, but (with the exception of controls unmatched for both birthweight and gestational age) were born significantly earlier than their siblings. A family history of preterm or small-for-gestational-age birth was found to affect the risk of cerebral palsy by influencing the risk of preterm birth or growth retardation in the index pregnancy.

Adolescent↗

Twins, triplets, and cerebral palsy in births in Western Australia in the 1980s.

OBJECTIVES: To examine the rate of cerebral palsy in twins and triplets in births from 1980 to 1989 in Western Australia and to identify factors associated with increase in risk. DESIGN: Pluralities for all births in Western Australia were identified through the standardised midwives' notification system, and cases of cerebral palsy were identified from the Western Australian cerebral palsy register. MAIN OUTCOME MEASURES: Multiple births, cerebral palsy, excluding postneonatal cause. RESULTS: The prevalence of cerebral palsy in triplets, of 28 per 1000 survivors to 1 year (95% confidence interval 11 to 63) exceeded that in twins (7.3; 5.2 to 10) and singletons (1.6; 1.4 to 1.8). Although twins and triples were more likely than singletons to be low in birth weight, their risks of cerebral palsy if low in birth weight were similar. In contrast, in normal birthweight categories twins had a higher rate of cerebral palsy (4.2; 2.2 to 7.7) than singletons (1.1; 1.0 to 1.3). The prevalence of cerebral palsy was similar in twins of unlike sex pairs, all of whom are dizygotic, and in like sex pairs. A twin pair in which one member died in utero was at higher risk of cerebral palsy: 96 per 1000 twin pairs (36 to 218) compared with 12 (8.2 to 17) for twin pregnancies in which both survived. There was a similar but non-significant trend for death of one triplet to be associated with increased risk of cerebral palsy in the survivors of the set. CONCLUSION: Triplet pregnancies produced a child with cerebral palsy 47 times more often than singleton pregnancies did and twin pregnancies eight times more often. Eighty six per cent of cerebral palsy in multiple births was in twins. As multiple births are increasing mainly because of personal and medical decisions the increased risk of cerebral palsy in multiple births is of concern.

Birth Order↗

Spastic quadriplegia in Western Australia: a genetic epidemiological study. I: Case population and perinatal risk factors.

In a case-control study of all cerebral palsy cases with moderate and severe spastic quadriplegia born between 1976 and 1985, males comprised three-quarters of the cases and tended to have more severe motor impairment than females. The majority of cases had multiple and severe disabilities, and 27 per cent had died by the time of data collection. There was an excess of low-birthweight and preterm births compared with all live births in WA. An intrapartum cause was considered possible in 18 of the 74 children; however, half of these had evidence of compromise before labour.

Australia↗

Spastic quadriplegia in Western Australia. II: Pedigrees and family patterns of birthweight and gestational age.

Pedigrees were obtained for all 74 index children and for three controls for each case. Recurrence of similar spastic quadriplegic phenotypes occurred in two families. A karyotype of 46,XY,dup(13)(q14q34), resulting in a partial trisomy 13, was found in another case. Rates of miscarriages and stillbirths plus neonatal deaths were higher among siblings of index cases than in siblings of birth-year controls, but were similar to siblings of birthweight controls. Average birthweights and gestational ages were lower in index cases than in birth-year controls. Children with spastic quadriplegia had significantly lower birthweights and gestational ages than their siblings. However, they also tended to come from families with a pattern of low birthweight and preterm delivery. The differences between families remained after controlling for factors affecting birthweight.

Australia↗

Use of automated sequencing of polymerase chain reaction-generated amplicons to identify three types of cholera toxin subunit B in Vibrio cholerae O1 strains.

Cholera toxin is the principal factor causing the profuse intestinal fluid secretion that is characteristic of cholera. The DNA sequences of the cholera toxin subunit B structural genes from 45 Vibrio cholerae O1 strains isolated in 29 countries over a period of 70 years were determined by automated DNA sequencing of polymerase chain reaction-generated amplicons. Three types of cholera toxin B subunit gene (ctxB) were identified. Genotype 1 was found in strains of classical biotype worldwide and El Tor biotype strains associated with the U.S. Gulf Coast, genotype 2 was found in El Tor biotype strains from Australia, and genotype 3 was found in El Tor biotype strains from the seventh pandemic and the recent Latin American epidemic. All base changes correspond to an amino acid substitution in the B subunit of the cholera toxin. Heterogenicity in the B subunit could have implications for vaccine development and diagnostic tests for cholera toxin and antitoxin. We conclude that this technology provides timely and potentially useful epidemiological information.

Africa↗

Cerebral palsy in multiple births in Western Australia: genetic aspects.

A study of cerebral palsy in multiple births was undertaken to test genetic involvement and assess the impact of the special conditions of pregnancy and parturition in these cases. Complete ascertainment of cerebral palsy in multiple gestations that occurred in Western Australia between 1956 and 1985 was obtained from the Western Australian Cerebral Palsy Register. There were 74 twins and 5 triplets. Data on sex, birth order, motor handicap, outcome in co-twins and triplets, zygosity, and pedigree information was obtained from the Register, hospital records, and, where possible, by interview of the parent(s) of the propositi. There was a significantly higher (P = 0.0026) concordance rate in MZ than in DZ twin pairs. However, pedigree studies showed no other relatives with a motor handicap similar to that of the propositi. This is consistent with a multifactorial cause in at least some of the cases. The sex ratio of affected twins was found to be 2.1 compared to 1.3 for singletons and all 5 affected triplets were boys. The trend of increasing sex ratio with increasing plurality was significant at the 1% level.

Birth Order↗