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G Patton

Publications and source records attributed to G Patton.

At least 19 recordsLinked to original sources
PubMed2003

Family risk factors for cannabis use: a population-based survey of Australian secondary school students.

The objective of this study was to investigate relationships between adolescent cannabis use and indices of parent - child attachment, family functioning and parent attitudes to drugs and delinquency. A total of 2848 year 9 and 2363 year 11 students participated in the Victorian Adolescent Health and Well-Being Survey (1999). The study was a school-based random sample of 535 metropolitan and rural, government and non-government secondary schools throughout Victoria, Australia. Cannabis use was defined as 'any' and 'weekly' use in the last 30 days. Multivariate logistic regression was used to identify independent associations between cannabis use and parent - child attachment, family functioning and parent attitudes to drugs and delinquency. Cannabis use in year 9 was associated with permissive parent attitudes to drugs and delinquency (any use: adjusted odds ratio (OR) = 8.1; weekly use: adjusted OR = 7.6), and was particularly sensitive to small changes in the quality of the parent - child relationship with risk increasing threefold for those describing their attachment as 'good' compared with 'very good' (any use: adjusted OR = 2.8, weekly use adjusted OR = 2.9). A similar, but more moderate pattern association was evident in year 11. After adjusting for other family and background factors, poor family functioning showed minimal association with level of cannabis use at both year levels. Results suggest that intervention efforts might sensibly target strengthening parent - children relationships and promoting less permissive parent attitudes to drug use.

Adolescent↗
PubMed2001

Electron arc irradiation of the postmastectomy chest wall with CT treatment planning: 20-year experience.

PURPOSE: Since 1980, electron arc irradiation of the postmastectomy chest wall has been the preferred radiotherapy technique at the University of Utah for patients with advanced breast cancer. We report the results of this technique in 156 consecutive Stage IIA-IIIB patients treated from 1980 to 1998. METHODS: CT treatment planning was used in all patients to identify chest wall thickness and internal mammary lymph node depth. Computerized dosimetry was used to deliver total doses of 50 Gy in 5-1/2 weeks to the chest wall and the internal mammary lymph nodes with electron arc therapy. Patients were assessed for local, regional, and distant control of disease and for survival. Univariate and multivariate proportional hazards were modeled using a hierarchical nonproportional semiparametric model testing the following prognostic factors: age, stage, tumor size, number of positive lymph nodes, estrogen receptor status, and dose. End points evaluated included disease-free survival, cause-specific survival, and overall survival. RESULTS: Eighty-one percent of patients were at high risk for local-regional failure because of > T2 primary tumor or > 3 positive axillary lymph nodes. The median number of positive lymph nodes was 5, and the median tumor size was 3.5 cm. Actuarial 10-year local-regional control and overall survival were 95% and 52%, respectively. In multivariate analysis, the only factor prognostic for disease-free survival, cause-specific survival, and overall survival was the number of positive lymph nodes (p < 0.001). The 10-year rates of local-regional control for patients with 0, 1-3, 4-9, and > or = 10 involved lymph nodes were 100%, 98%, 93%, and 89%, respectively. The only rates of acute and chronic radiotherapy toxicity > or = 2 by RTOG/EORTC criteria were skin related and observed in 44% and 10% for acute and late reactions, respectively. CONCLUSION: These data demonstrate excellent local-regional control rates with electron arc therapy of the postmastectomy chest wall in patients with advanced breast cancer. Our 20-year experience with electron arc radiotherapy has demonstrated the safety and efficacy of this technique. The advantage of this technique is that the internal mammary lymph node chain can be easily encompassed while the dose to heart and lung is minimized; it also obviates match lines in areas of high risk.

Adult↗
PubMed2001

Does bullying cause emotional problems? A prospective study of young teenagers.

OBJECTIVES: To establish the relation between recurrent peer victimisation and onset of self reported symptoms of anxiety or depression in the early teen years. DESIGN: Cohort study over two years. SETTING: Secondary schools in Victoria, Australia. PARTICIPANTS: 2680 students surveyed twice in year 8 (aged 13 years) and once in year 9. MAIN OUTCOME MEASURES: Self reported symptoms of anxiety or depression were assessed by using the computerised version of the revised clinical interview schedule. Incident cases were students scoring >/=12 in year 9 but not previously. Prior victimisation was defined as having been bullied at either or both survey times in year 8. RESULTS: Prevalence of victimisation at the second survey point in year 8 was 51% (95% confidence interval 49% to 54%), and prevalence of self reported symptoms of anxiety or depression was 18% (16% to 20%). The incidence of self reported symptoms of anxiety or depression in year 9 (7%) was significantly associated with victimisation reported either once (odds ratio 1.94, 1.1 to 3.3) or twice (2.30, 1.2 to 4.3) in year 8. After adjustment for availability of social relations and for sociodemographic factors, recurrent victimisation remained predictive of self reported symptoms of anxiety or depression for girls (2.60, 1.2 to 5.5) but not for boys (1.36, 0.6 to 3.0). Newly reported victimisation in year 9 was not significantly associated with prior self report of symptoms of anxiety or depression (1.48, 0.4 to 6.0). CONCLUSION: A history of victimisation and poor social relationships predicts the onset of emotional problems in adolescents. Previous recurrent emotional problems are not significantly related to future victimisation. These findings have implications for how seriously the occurrence of victimisation is treated and for the focus of interventions aimed at addressing mental health issues in adolescents.

Adolescent↗
PubMed2001

Adverse outcomes of alcohol use in adolescents.

AIMS: To compare the occurrence of behaviours occurring under the influence of alcohol in 16-17-year-olds and determine associated risk factors for the different behaviours. DESIGN/SETTING: Cross-sectional survey administered by laptop computers in secondary schools across the state of Victoria, Australia. MEASUREMENT/FINDINGS: The participation rate was 79%. Seventy per cent of participants drank alcohol; 17% of drinkers reported alcohol-related violence (accidents or injuries) and 15% reported problems relating to sex under the influence of alcohol (having sex and later regretting it or having had unsafe sex) in the previous 12 months. Males were more likely to report alcohol-related violence (20% compared to 14% females). Almost one in 10 young people reported having sex while under the influence of alcohol and later regretting it and 10% reported having had unsafe sex. There were no significant gender differences in the reporting rates of alcohol-related sexual risk taking (prop. cum. OR 1.1, 95% CI 0.68-1.9). For alcohol-related injuries, strong independent associations were found with dose of alcohol consumed (prop. cum. OR 2.3, 95% CI 1.3-4.0), frequency of alcohol consumption (prop. cum. OR 2.7, 95% CI 0.94-7.5), antisocial behaviour (prop. cum. OR 2.4, 95% CI 1.4-4.1) and peer drinking (prop. cum. OR 3.3, 95% CI 1.4-8.1). For alcohol-related sexual risk-taking, psychiatric morbidity (prop. cum. OR 4.1, 95% CI 1.9-9.0) and high frequency of alcohol consumption (prop. cum. OR 2.0, 95% CI 0.87-4.6) had strong independent associations. CONCLUSIONS: Physical injury and high-risk sexual behaviour under the influence of alcohol are common in teenagers. Alcohol-related physical injury appears closely related to patterns of alcohol consumption whereas alcohol-related sexual risk-taking is most closely associated with symptoms of depression and anxiety.

Adolescent↗
PubMed2001

O2-dependent prostanoid synthesis activates functional PGE receptors on corpus cavernosum smooth muscle.

We have previously demonstrated that decreased O2 tension inhibits prostaglandin synthesis from human corpus cavernosum smooth muscle cells in static culture over 8-18 h (R. B. Moreland et al., Molecular Urology 2: 41-47, 1998). In this report, an experimental system was designed that allowed determination of the effects of O2 tension changes over the time frame of physiological penile erection. Human corpus cavernosum smooth muscle cells were cultured on microcarrier beads in enclosed stirrer flasks so that rapid changes of O2 tension could be modulated. After 18 h of equilibration at 30-40 mmHg to simulate blood PO2 at penile flaccidity, O2 tension was increased to 100 mmHg for 1 h and then returned to 30-40 mmHg. Media samples were withdrawn for prostanoid synthesis and cell samples were taken for cAMP determinations. After 18 h of 30-40 mmHg PO2 values, prostanoid synthesis by human corpus cavernosum smooth muscle cells was low (0.1-0.7 pmol/10(6) cells). When PO2 was increased to 100 mmHg, a rapid increase in PGE2 >> PGF2alpha > PGD2 was observed (thromboxane A2 was undetectable), which peaked at 5.7 pmol PGE2/10(6) cells. Increased O2 tension correlated with increased PGE2 and increased intracellular synthesis of cAMP. The prostaglandin G/H synthase inhibitor indomethacin or the E prostanoid (EP2)-selective antagonist AH-6809 each inhibited the O2-tension-dependent increases in cAMP. These data support a role of differential O2 tension in the penis in the smooth muscle synthesis of PGE2, which in turn increases cAMP synthesis via EP2 receptors.

Autocrine Communication↗
PubMed2001

Differential susceptibility of retroviruses to nucleoside analogues.

Retroviruses may cause diseases in their vertebrate hosts. They are distinguished by their common means of replication involving reverse transcription, a process inhibited by nucleoside reverse transcriptase inhibitors (NRTIs) and other compounds used in antiretroviral chemotherapy. Previous work on NRTIs has been limited to their effect on human immunodeficiency virus (HIV) (for review see Ho & Hitchcock, 1989; Weller, 1999) and little information exists regarding the efficacy and therapeutic potential of these drugs against other retroviruses. We have tested all six NRTIs licensed for HIV treatment [didanosine (ddI), zalcitabine (ddC), lamivudine (3TC), stavudine (d4T), zidovudine (AZT) and abacavir (ABC)] against seven retroviruses representative of the traditional subfamilies: Spumavirinae, Lentivirinae and the Oncovirinae. As expected, each drug showed a range of activities against the panel of retroviruses, some drugs inhibiting other viruses at concentrations well below those required for HIV. Overall, AZT was the most active inhibitor (IC50 range, 0.032-1.0 microM), being most active against the Spuma (foamy) viruses. Abacavir was inhibitory for HIV-1, MN strain (HIV-1 MN), amphotrophic murine leukemia virus (MLV-A) and simian foamy virus type 6 (SFV-6). The least effective inhibitor, 3TC (IC50 range, 0.32->100 microM), was most potent against simian retrovirus types 1 and 2 (SRV-1, SRV-2) and HIV-1, but did not inhibit foamy viruses and MLV-A. Additionally, there were differences in the concentration of drug required to inhibit closely related viruses. Taken together, these data suggest that NRTIs have a wide spectrum of antiretroviral activity and the activity of compounds, even against closely related retroviruses, cannot be predicted.

Animals↗
PubMed1997

Acne in Victorian adolescents: associations with age, gender, puberty and psychiatric symptoms.

OBJECTIVES: This study aimed to examine the associations between the frequency and severity of self-reported acne and age, gender, puberty and psychiatric symptoms in Victorian adolescents. METHODOLOGY: A sample of secondary schoolchildren in Victoria, Australia were surveyed using a computerized questionnaire. Developmental and psycho-social factors associated with acne were recorded and analysed using logistic regression. RESULTS: The Victorian Adolescent Health Survey (1992) recorded the frequency and severity of self-reported acne in 2491 students. Frequency of acne increased with age and pubertal development. For females commencement of menstruation was associated with increased frequency of acne. Asian born male students were less likely to report acne than Australian born males. Acne severity was coded into mild (students reporting acne sometimes on back or face) and moderate (students reporting acne often on face or back). Students reporting moderate acne were more likely to report a high level of psychiatric symptoms and were in the later stages of puberty. CONCLUSIONS: This study confirms an association between the frequency and severity of self-reported acne and stage of pubertal development. It showed also that students reporting moderate acne were more likely to report psychiatric symptoms of depression and anxiety.

Acne Vulgaris↗
PubMed1996

The branched eating disorders test: validity in a nonclinical population.

OBJECTIVE: To develop an effective measure of the symptoms of eating disorders for use in community surveys. METHOD: A branched eating disorders instrument for administration by notebook computer was evaluated as a screen in 487 teenage schoolgirls. High scorers and a stratified sample of low scorers were evaluated in a second-stage interview with the Eating Disorders Examination (EDE). RESULTS: The Branched Eating Disorders Test (BET) proved to have exceptional validity coefficients (sensitivity 100%, specificity 99%, positive predictive value 70%). DISCUSSION: This pilot validation suggests that the BET largely overcomes the problems of earlier instruments of limited screening utility when applied to community samples.

Adolescent↗
PubMed1996

The association between secondary amenorrhea and common eating disordered weight control practices in an adolescent population.

PURPOSE: This study examined the relative importance of low weight, in contrast with other symptoms of eating disorder, as a determinant of amenorrhea. METHODS: A cross-sectional survey was conducted of students at Year 10 (mean age 15.0 years) attending 43 schools in the state of Victoria. Amenorrhea and symptoms of eating disorder were assessed using the Branched Eating Disorders Test, administered through the medium of a notebook computer. RESULTS: The survey response rate was 84% (n = 886). A total of 23% (n = 205) reported either fasting or purging in the previous month. Secondary amenorrhea of at least 3 months duration was reported by 4.1% (n = 35). No statistically significant association was found between amenorrhea and body mass index. In contrast, 40% of amenorrheic subjects reported fasting or purging (P = .03), an association most evident in the heaviest subjects. CONCLUSION: These finding suggests that secondary amenorrhea may develop in normal and above-weight teenagers who engage in eating disordered weight control practices.

Adolescent↗
PubMed1996

Computer administration of a school-based adolescent health survey.

OBJECTIVE: To examine the utility of notebook computers in the collection of data in large scale surveys. METHODOLOGY: A notebook computer administered survey of health in adolescents was conducted in 1992 using a multi-instrument questionnaire. Students in school years 7, 9 and 11 in private and government schools in Melbourne and rural Victoria participated. RESULTS: Parental consent was obtained with an 83% response rate. Each student answered questions directly onto the computer taking an average of 68 min to complete the highly branched confidential but not anonymous questionnaire. Students were presented with on average 33% of the 897 possible questions. Over 90% of students reported enjoying using the computer. Those who reported answering the questions honestly all the time ranged from 68 to 85%, increasing with grade level. CONCLUSIONS: The use of computers in survey research provides many advantages in data collection including exposure only to relevant questions and the opportunity of asking sensitive questions.

Adolescent↗
PubMed1995

Primary care assessment of a patient with an eating disorder.

Eating disorders have become commoner in young Australian women over the past two decades, making their presentation in general practice more likely. Eating disorders vary considerably in severity from brief single episodes to severe disorders with prominent weight loss or maladaptive behaviours. Assessment should therefore focus on estimating the severity of the disorder to indicate the most appropriate treatment approaches.

Adolescent↗