John B Carlin | Murdoch Childrens Research Institute (original) (raw)
Papers by John B Carlin
Human Molecular Genetics, 2010
Mounting evidence from both animal and human studies suggests that the epigenome is in constant d... more Mounting evidence from both animal and human studies suggests that the epigenome is in constant drift over the life course in response to stochastic and environmental factors. In humans, this has been highlighted by a small number of studies that have demonstrated discordant DNA methylation patterns in adolescent or adult monozygotic (MZ) twin pairs. However, to date, it remains unclear when such differences emerge, and how prevalent they are across different tissues. To address this, we examined the methylation of four differentially methylated regions associated with the IGF2/H19 locus in multiple birth tissues derived from 91 twin pairs: 56 MZ and 35 dizygotic (DZ). Tissues included cord blood-derived mononuclear cells and granulocytes, human umbilical vein endothelial cells, buccal epithelial cells and placental tissue. Considerable variation in DNA methylation was observed between tissues and between unrelated individuals. Most interestingly, methylation discordance was also present within twin pairs, with DZ pairs showing greater discordance than MZ pairs. These data highlight the variable contribution of both intrauterine environmental exposures and underlying genetic factors to the establishment of the neonatal epigenome of different tissues and confirm the intrauterine period as a sensitive time for the establishment of epigenetic variability in humans. This has implications for the effects of maternal environment on the development of the newborn epigenome and supports an epigenetic mechanism for the previously described phenomenon of 'fetal programming' of disease risk.
Australian and New Zealand Journal of Psychiatry, 2007
To examine the extent to which excessive drinking in young adults is associated with alcohol abus... more To examine the extent to which excessive drinking in young adults is associated with alcohol abuse and dependence. Cross-sectional analyses were conducted using data from the eighth wave of the Victorian Adolescent Health Cohort Study, which comprised 1943 Victorians currently aged 24-25 years drawn from 44 secondary schools across the state in 1992. The main outcome measures of interest were short-term risk drinking status (based on daily alcohol consumption) and long-term risk drinking status (based on total weekly alcohol consumption). Two out of 5 participants drank at moderate to high risk levels for short-term harm. Yet, because young people tend to drink on only 1-2 days a week, fewer (22%) were at moderate to high risk for long-term harm. Although 20% of the participants met criteria for a diagnosis of alcohol abuse or dependence, most of those in the moderate- to high-risk drinking categories were not diagnosed with either alcohol disorder. Excessive alcohol use in one or two sessions a week appears to be common in young Australian adults. While short- and long-term risky drinking is more common in those with an alcohol use disorder, the majority of moderate- and high-risk drinking is done by those who do not meet criteria for an alcohol use disorder.
Statistical Science, 2013
ABSTRACT
Psychological Bulletin, 1991
Australian and New Zealand Journal of Psychiatry, 2000
Psychological Medicine, 1997
Reports of adolescent suicidal behaviour have generally derived from clinical settings but popula... more Reports of adolescent suicidal behaviour have generally derived from clinical settings but population-based studies are likely to provide a clearer epidemiological view. Non-fatal suicidal behaviours were studied in 1699 Australian 15- to 16-year-old secondary school students at 44 schools in the state of Victoria, Australia. Self-reported episodes of self-harm were characterized using items from the Beck Suicide Intent Scale. The 12 month weighted prevalence estimate for deliberate self-harm was 5.1%. The commonest forms were self-laceration (1.7%), self-poisoning (1.5%) and deliberate recklessness (1.8%). Self-poisoning and self-laceration were commoner in girls. The prevalence of 'true suicide attempts' was 0.2%. Most self-harmers did not perceive death as likely, plan self-harming episodes at length or inform others of the episodes. Psychiatric morbidity had the strongest association with self-harm, an association which held for all subtypes. Antisocial behaviour and substance abuse were associated with self-harm in girls but not boys. Sexual activity was independently associated with self-harm in both genders. Deliberate self-harm was common but the great majority of episodes were not 'true suicide attempts'. It is, therefore, possible that attributable mortality and morbidity may be greater in self-harmers without definite suicidal intent.
Journal of Allergy and Clinical Immunology, 1998
Asthma severity among mite-sensitized individuals appears to be related to the degree of mite all... more Asthma severity among mite-sensitized individuals appears to be related to the degree of mite allergen exposure. The objective of this study was to assess the long-term effectiveness of mite avoidance measures in the homes of asthmatic children in Melbourne, Australia. The concentration of house dust mite allergen (Der p 1) was measured on the child's mattress surfaces and bedroom floors in 85 homes on 10 occasions over a 16-month period. After the first three visits, all mattresses were covered with a semipermeable encasement, and carpeted bedroom floors were randomly allocated to regular applications of a placebo or an "anti-mite" shampoo. The concentration of Der p 1 recovered was initially high in the carpeted bedrooms (n = 66) (41.1, 95% confidence interval, 30.7 to 55.0 microg Der p 1 per gm) and mattresses (n = 85) (39.6, 27.2 to 57.7). During the initial observation period the concentration of mite allergen fell in the treatment, placebo, and parental control groups. During the seven treatment periods, no differences were seen between the Der p 1 concentrations in the groups using the "anti-mite" shampoo, placebo shampoo, or the parental control group (e.g., at visit 4; 12.6, 8.2 to 19.5; 14.8, 8.6 to 25.1; and 12.0, 8.1 to 17.7 microg/gm, respectively). In contrast, the concentration of Der p 1 in samples from uncarpeted floors and mattress encasements was low (4.1, 2.1 to 8.0 microg/gm and 4.2, 2.6 to 6.5 microg/gm, respectively) and insufficient dust for analysis was frequently obtained from these sites. There was no additional benefit from the use of an "anti-mite" shampoo. The absence of carpets and the use of mattress encasements was a useful long-term strategy for mite allergen avoidance.
Psychological Bulletin, 1991
Developmental Medicine & Child Neurology, 2004
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](Statistical Science, 1993
Developmental Medicine & Child Neurology, 2008
American Journal of Public Health, 2006
The Journal of Pediatrics, 2006
This study aimed to investigate risk factors for the development of intussusception in infants in... more This study aimed to investigate risk factors for the development of intussusception in infants in a developing country with a suspected high incidence and in a developed country with a low incidence. A prospective case-control study of infants <2 years of age with idiopathic intussusception confirmed by air enema or surgery was conducted at the National Hospital of Paediatrics (NHP), Vietnam (n = 533) and the Royal Children's Hospital (RCH), Australia (n = 51). Diagnosis was validated in a subset (84% NHP; 67% RCH) by an independent blinded radiologist. Risk factor assessment was performed using a standardized questionnaire. Stool specimens were assayed for bacterial, viral, and parasitic agents. The incidence of intussusception in Vietnam was 302/100,000 in infants <1 year of age (95% CI: 258-352), substantially higher than in Australia (71/100,000). A strong association with adenovirus infection was observed at both sites (cases positive at NHP: 34%, OR 8.2; cases positive at RCH: 40%, OR 44). No association was identified between intussusception and rotavirus, other enteric pathogens, oral polio vaccine, feeding practices, or living conditions. The incidence of intussusception in infants was markedly higher in Vietnam than in Australia. A strong association between adenovirus infection and intussusception was identified at both sites suggesting that adenovirus may play a role in the etiology of intussusception.
Bulletin of the World Health Organization, 2006
Developmental Medicine & Child Neurology, 2007
Journal of Adolescent Health, 2007
Psychological Medicine, 1997
Addiction, 1998
To examine the uptake and course of smoking in a representative adolescent cohort. Six-wave cohor... more To examine the uptake and course of smoking in a representative adolescent cohort. Six-wave cohort study. Secondary school students initially aged 14-15 years at 44 schools in the state of Victoria, Australia. Computerized questionnaire including 7-day retrospective recall for tobacco use. Prevalence rates for smoking in the past month rose from 25% to 31% and daily smoking 9% to 18% across the 3-year follow-up. Forty-five per cent of the sample smoked at some point but only 18% were daily smokers at the end-point. High rates of short-term cessation were observed for both experimental and daily smokers, but 70% of daily smokers relapsed within 12 months. Occasional smoking at the outset was the strongest predictor of later daily smoking and was also predictive of lower cessation and higher relapse rates. Parental divorce and parental daily smoking were associated with smoking at the outset and parental smoking was strongly predictive of the course of daily smoking. In contrast, prevalence rates of smoking in a subject's school did not significantly predict either smoking initiation or subsequent course. Female daily smokers were half as likely as males to cease smoking, a finding that accounted for gender differences in smoking prevalence in this sample. The strength of association between occasional and later daily smoking indicates the importance of primary prevention but the variability in the early course indicates that there should be much scope for promotion of adolescent efforts to quit. Both the diminished likelihood of smoking cessation in young women and parental influences on smoking course deserve further exploration.
Human Molecular Genetics, 2010
Mounting evidence from both animal and human studies suggests that the epigenome is in constant d... more Mounting evidence from both animal and human studies suggests that the epigenome is in constant drift over the life course in response to stochastic and environmental factors. In humans, this has been highlighted by a small number of studies that have demonstrated discordant DNA methylation patterns in adolescent or adult monozygotic (MZ) twin pairs. However, to date, it remains unclear when such differences emerge, and how prevalent they are across different tissues. To address this, we examined the methylation of four differentially methylated regions associated with the IGF2/H19 locus in multiple birth tissues derived from 91 twin pairs: 56 MZ and 35 dizygotic (DZ). Tissues included cord blood-derived mononuclear cells and granulocytes, human umbilical vein endothelial cells, buccal epithelial cells and placental tissue. Considerable variation in DNA methylation was observed between tissues and between unrelated individuals. Most interestingly, methylation discordance was also present within twin pairs, with DZ pairs showing greater discordance than MZ pairs. These data highlight the variable contribution of both intrauterine environmental exposures and underlying genetic factors to the establishment of the neonatal epigenome of different tissues and confirm the intrauterine period as a sensitive time for the establishment of epigenetic variability in humans. This has implications for the effects of maternal environment on the development of the newborn epigenome and supports an epigenetic mechanism for the previously described phenomenon of 'fetal programming' of disease risk.
Australian and New Zealand Journal of Psychiatry, 2007
To examine the extent to which excessive drinking in young adults is associated with alcohol abus... more To examine the extent to which excessive drinking in young adults is associated with alcohol abuse and dependence. Cross-sectional analyses were conducted using data from the eighth wave of the Victorian Adolescent Health Cohort Study, which comprised 1943 Victorians currently aged 24-25 years drawn from 44 secondary schools across the state in 1992. The main outcome measures of interest were short-term risk drinking status (based on daily alcohol consumption) and long-term risk drinking status (based on total weekly alcohol consumption). Two out of 5 participants drank at moderate to high risk levels for short-term harm. Yet, because young people tend to drink on only 1-2 days a week, fewer (22%) were at moderate to high risk for long-term harm. Although 20% of the participants met criteria for a diagnosis of alcohol abuse or dependence, most of those in the moderate- to high-risk drinking categories were not diagnosed with either alcohol disorder. Excessive alcohol use in one or two sessions a week appears to be common in young Australian adults. While short- and long-term risky drinking is more common in those with an alcohol use disorder, the majority of moderate- and high-risk drinking is done by those who do not meet criteria for an alcohol use disorder.
Statistical Science, 2013
ABSTRACT
Psychological Bulletin, 1991
Australian and New Zealand Journal of Psychiatry, 2000
Psychological Medicine, 1997
Reports of adolescent suicidal behaviour have generally derived from clinical settings but popula... more Reports of adolescent suicidal behaviour have generally derived from clinical settings but population-based studies are likely to provide a clearer epidemiological view. Non-fatal suicidal behaviours were studied in 1699 Australian 15- to 16-year-old secondary school students at 44 schools in the state of Victoria, Australia. Self-reported episodes of self-harm were characterized using items from the Beck Suicide Intent Scale. The 12 month weighted prevalence estimate for deliberate self-harm was 5.1%. The commonest forms were self-laceration (1.7%), self-poisoning (1.5%) and deliberate recklessness (1.8%). Self-poisoning and self-laceration were commoner in girls. The prevalence of 'true suicide attempts' was 0.2%. Most self-harmers did not perceive death as likely, plan self-harming episodes at length or inform others of the episodes. Psychiatric morbidity had the strongest association with self-harm, an association which held for all subtypes. Antisocial behaviour and substance abuse were associated with self-harm in girls but not boys. Sexual activity was independently associated with self-harm in both genders. Deliberate self-harm was common but the great majority of episodes were not 'true suicide attempts'. It is, therefore, possible that attributable mortality and morbidity may be greater in self-harmers without definite suicidal intent.
Journal of Allergy and Clinical Immunology, 1998
Asthma severity among mite-sensitized individuals appears to be related to the degree of mite all... more Asthma severity among mite-sensitized individuals appears to be related to the degree of mite allergen exposure. The objective of this study was to assess the long-term effectiveness of mite avoidance measures in the homes of asthmatic children in Melbourne, Australia. The concentration of house dust mite allergen (Der p 1) was measured on the child's mattress surfaces and bedroom floors in 85 homes on 10 occasions over a 16-month period. After the first three visits, all mattresses were covered with a semipermeable encasement, and carpeted bedroom floors were randomly allocated to regular applications of a placebo or an "anti-mite" shampoo. The concentration of Der p 1 recovered was initially high in the carpeted bedrooms (n = 66) (41.1, 95% confidence interval, 30.7 to 55.0 microg Der p 1 per gm) and mattresses (n = 85) (39.6, 27.2 to 57.7). During the initial observation period the concentration of mite allergen fell in the treatment, placebo, and parental control groups. During the seven treatment periods, no differences were seen between the Der p 1 concentrations in the groups using the "anti-mite" shampoo, placebo shampoo, or the parental control group (e.g., at visit 4; 12.6, 8.2 to 19.5; 14.8, 8.6 to 25.1; and 12.0, 8.1 to 17.7 microg/gm, respectively). In contrast, the concentration of Der p 1 in samples from uncarpeted floors and mattress encasements was low (4.1, 2.1 to 8.0 microg/gm and 4.2, 2.6 to 6.5 microg/gm, respectively) and insufficient dust for analysis was frequently obtained from these sites. There was no additional benefit from the use of an "anti-mite" shampoo. The absence of carpets and the use of mattress encasements was a useful long-term strategy for mite allergen avoidance.
Psychological Bulletin, 1991
Developmental Medicine & Child Neurology, 2004
Statistical Science, 1993
Developmental Medicine & Child Neurology, 2008
American Journal of Public Health, 2006
The Journal of Pediatrics, 2006
This study aimed to investigate risk factors for the development of intussusception in infants in... more This study aimed to investigate risk factors for the development of intussusception in infants in a developing country with a suspected high incidence and in a developed country with a low incidence. A prospective case-control study of infants <2 years of age with idiopathic intussusception confirmed by air enema or surgery was conducted at the National Hospital of Paediatrics (NHP), Vietnam (n = 533) and the Royal Children's Hospital (RCH), Australia (n = 51). Diagnosis was validated in a subset (84% NHP; 67% RCH) by an independent blinded radiologist. Risk factor assessment was performed using a standardized questionnaire. Stool specimens were assayed for bacterial, viral, and parasitic agents. The incidence of intussusception in Vietnam was 302/100,000 in infants <1 year of age (95% CI: 258-352), substantially higher than in Australia (71/100,000). A strong association with adenovirus infection was observed at both sites (cases positive at NHP: 34%, OR 8.2; cases positive at RCH: 40%, OR 44). No association was identified between intussusception and rotavirus, other enteric pathogens, oral polio vaccine, feeding practices, or living conditions. The incidence of intussusception in infants was markedly higher in Vietnam than in Australia. A strong association between adenovirus infection and intussusception was identified at both sites suggesting that adenovirus may play a role in the etiology of intussusception.
Bulletin of the World Health Organization, 2006
Developmental Medicine & Child Neurology, 2007
Journal of Adolescent Health, 2007
Psychological Medicine, 1997
Addiction, 1998
To examine the uptake and course of smoking in a representative adolescent cohort. Six-wave cohor... more To examine the uptake and course of smoking in a representative adolescent cohort. Six-wave cohort study. Secondary school students initially aged 14-15 years at 44 schools in the state of Victoria, Australia. Computerized questionnaire including 7-day retrospective recall for tobacco use. Prevalence rates for smoking in the past month rose from 25% to 31% and daily smoking 9% to 18% across the 3-year follow-up. Forty-five per cent of the sample smoked at some point but only 18% were daily smokers at the end-point. High rates of short-term cessation were observed for both experimental and daily smokers, but 70% of daily smokers relapsed within 12 months. Occasional smoking at the outset was the strongest predictor of later daily smoking and was also predictive of lower cessation and higher relapse rates. Parental divorce and parental daily smoking were associated with smoking at the outset and parental smoking was strongly predictive of the course of daily smoking. In contrast, prevalence rates of smoking in a subject's school did not significantly predict either smoking initiation or subsequent course. Female daily smokers were half as likely as males to cease smoking, a finding that accounted for gender differences in smoking prevalence in this sample. The strength of association between occasional and later daily smoking indicates the importance of primary prevention but the variability in the early course indicates that there should be much scope for promotion of adolescent efforts to quit. Both the diminished likelihood of smoking cessation in young women and parental influences on smoking course deserve further exploration.