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Biomedical subjects

R J Bell

Publications and source records attributed to R J Bell.

At least 19 recordsLinked to original sources
PubMed2006

Homocysteine, estrogen and cognitive decline.

BACKGROUND: Factors that contribute to cognitive decline in women from midlife remain poorly understood. There are circumstantial data indicating a positive association between homocysteine and cognitive decline and that endogenous and exogenous estrogen may influence homocysteine levels. The aim of this review was to establish what is known of the relationships between cognitive change and homocysteine levels, and the impact of the menopause transition and exogenous estrogen on homocysteine levels. METHODS: We reviewed the recent published literature from 1993 to 2005 pertaining to the current understanding of the relationship(s) between plasma homocysteine levels and cognitive functioning and endogenous hormone levels and exogenous estrogen use in women. RESULTS: Hyperhomocysteinemia is consistently associated with cognitive decline. Dietary supplementation with vitamins may assist in normalizing homocysteine levels; however, there is no evidence that this results in favorable effects on cognition. Changes in endogenous estrogen levels are inversely associated with changes in serum homocysteine. Consistent with this, estrogen therapy is associated with reductions in plasma homocysteine, with the greatest effects reported in women with higher levels of homocysteine at baseline. Limited data indicate that tibolone is associated with little change in homocysteine. The use of raloxifene, the most studied selective estrogen receptor modulator, is associated with a modest reduction in homocysteine. CONCLUSIONS: There are data to suggest an underlying link between homocysteine levels and cognitive decline. There is also evidence for a link between both the menopause transition and use of exogenous estrogen therapy and homocysteine levels. Clinical data do not support a role for exogenous estrogen in the prevention of dementia in older women; however, the 'window of opportunity' theory suggests that there is a need for randomized controlled trials to evaluate the role of estrogen in the early postmenopausal years to protect against cognitive decline in later life.

Cognition↗
PubMed2004

Do women know that prenatal testing detects fetuses with Down syndrome?

This questionnaire-based study in Victoria, Australia, examined the responses of pregnant women, aged 37 years and over, to a question about what they expected prenatal testing (screening and/or diagnosis) for birth defects to tell them about their pregnancy. Content analysis showed that, of the 432 tested women, 61.3% mentioned Down syndrome, chromosomal abnormalities or trisomies. Women undergoing both screening and diagnosis were more likely than those having one or other test to mention Down syndrome (adjusted OR = 1.6, P = 0.06), having adjusted for age, marital status, education, residence and parity. Similarly, those from an English-speaking background were more likely to mention Down syndrome, etc. compared to women from a non-English-speaking background (adjusted OR = 3.5, P < 0.001). Down syndrome, a fundamental piece of information about prenatal tests, was not mentioned in nearly 40% of women's responses. This suggests that pregnant women need clearer information about prenatal testing, including the conditions that might be detected.

Analysis of Variance↗
PubMed2003

Suicide prevention in first episode psychosis: the development of a randomised controlled trial of cognitive therapy for acutely suicidal patients with early psychosis.

BACKGROUND: Young people with early psychosis are at particularly high risk of suicide. However, there is evidence that early intervention can reduce this risk. Despite these advances, first episode psychosis patients attending these new services still remain at risk. To address this concern, a program called LifeSPAN was established within the Early Psychosis Prevention and Intervention Centre (EPPIC). The program developed and evaluated a number of suicide prevention strategies within EPPIC and included a cognitively oriented therapy (LifeSPAN therapy) for acutely suicidal patients with psychosis. We describe the development of these interventions in this paper. METHOD: Clinical audit and surveys provided an indication of the prevalence of suicidality among first episode psychosis patients attending EPPIC. Second, staff focus groups and surveys identified gaps in service provision for suicidal young people attending the service. Third, a suicide risk monitoring system was introduced to identify those at highest risk. Finally, patients so identified were referred to and offered LifeSPAN therapy whose effectiveness was evaluated in a randomised controlled trial. RESULTS: Fifty-six suicidal patients with first episode psychosis were randomly assigned to standard clinical care or standard care plus LifeSPAN therapy. Forty-two patients completed the intervention. Clinical ratings and measures of suicidality and risk were assessed before, immediately after the intervention, and 6 months later. Benefits were noted in the treatment group on indirect measures of suicidality, e.g., hopelessness. The treatment group showed a greater average improvement (though not significant) on a measure of suicide ideation. CONCLUSIONS: Early intervention in psychosis for young people reduces the risk of suicide. Augmenting early intervention with a suicide preventative therapy may further reduce this risk.

Acute Disease↗
PubMed2001

Women's health issues in haemodialysis patients.

OBJECTIVES: To describe reproductive health issues in women with end-stage renal disease (ESRD) treated with haemodialysis. STUDY DESIGN: Cross-sectional survey based on structured interviews. SETTING: Nephrology units of two major metropolitan tertiary referral hospitals in Victoria and their satellite dialysis centres between 1 November 1998 to 30 June 1999. METHODS: Women aged 20 years or over in haemodialysis programs. OUTCOME MEASURES: Menstrual status; prevalence of menstrual and climacteric symptoms; use of gynaecological screening; and prevalence of comorbidities that may benefit from hormone replacment therapy. RESULTS: 48 women completed the survey. They were similar to the 485 women undergoing haemodialysis in Victoria in age (mean age, 55.5 years; range, 20-84 years), years on dialysis (mean age, 3.9 years; range, 1 month-17 years) and primary diagnosis. Eleven of the 15 premenopausal women reported menstrual cycles of 22-35 days, 13 reported common premenstrual symptoms, and six reported dysmenorrhoea that interfered with daily activities. Average age at menopause was 47.7 years (95% CI, 45.6-49.9 years), and six of the 31 postmenopausal women underwent menopause before 45 years. Eight had ever been prescribed hormone replacement therapy (oral in all cases). Over half the women (26) had not had a Pap smear in the last two years, and 12 of those aged over 50 (38%) had not had a mammogram in the same period. CONCLUSION: Despite their risk of early menopause, cardiovascular disease and bone fracture, few women undergoing haemodialysis were offered hormone replacement therapy. Nor were they adequately screened for gynaecological cancers. Women's health issues seem to be neglected among haemodialysis patients.

Adult↗
PubMed2001

Prenatal diagnosis for women aged 37 years and over: to have or not to have.

Forty percent of pregnant women aged 37 years and over do not have prenatal diagnosis despite being eligible for a free test. The present study aimed to determine how often, and which, untested women were making a choice about this, how many declined an offer and why. A questionnaire was given to untested women, aged 37 years and over, at no less than 24 weeks gestation. A total of 375 (81.5%) women declined, 72 (16%) were not offered a test and 13 presented too late antenatally. There was a three-fold increased likelihood (OR 3.10 95% CI 1.44, 6.65) of no offer for urban non-English speaking background women, compared with the reference group (metropolitan, English speaking). Unpartnered women were also significantly less likely to receive an offer (OR 3.18, 95% CI 1.19, 8.46). Risk to the baby was the main reason for declining. When offered non-invasive prenatal screening, most decliners of prenatal diagnosis accepted, even those who declined because they were opposed to abortion. We estimate that overall 33% of older pregnant women were being offered and declining amniocentesis and/or chorion villus sampling (CVS). Only 6% were not offered a test, but this small proportion is over-represented by minority groups who must be given equal opportunity to make this choice.

Adult↗
PubMed1997

Women who spontaneously quit smoking in early pregnancy.

Spontaneous quitters are prepregnancy smokers who quit by the time of their first antenatal visit. We recruited 192 self-declared spontaneous quitters and 407 smokers at their first visit to the antenatal clinic at the Royal Women's Hospital during April, 1994-May, 1995. Spontaneous quitters made up 23% of prepregnancy smokers. Information about self-declared quitters and smokers was collected by self-completed questionnaires. Urine samples collected at the first visit and in late pregnancy were assayed for cotinine to validate smoking status. A cut-off urinary concentration of > or = 653 nmol/L cotinine was used to determine active smoking. At the first visit, 20% of the self-declared spontaneous quitters were smoking and by late pregnancy, regardless of their initial biochemically verified status, 27% were smoking. Spontaneous quitters were different from women who said they were still smoking at their first antenatal visit, in a range of demographic variables and measures of addictive behaviour.

Adult↗
PubMed1995

A malathion resistance gene associated with increased life span of the rusty grain beetle, Cryptolestes ferrugineus (Coleoptera: Cucujidae).

The life span of the rusty grain beetle, Cryptolestes ferrugineus, was determined at 30 degrees C, 75% relative humidity (RH) for virgin and mated adults of a malathion-resistant strain (BC6RR), a malathion-susceptible strain (SS), the F1 progeny of a cross between resistant females and susceptible males (RS), and an outbred strain (GV). The BC6RR strain was derived from the SS strain by incorporating the malathion resistance gene into the susceptible genome with six backcrosses and recovery of heterozygous resistant F1 adults between crosses. The mean life span of virgin, malathion-resistant adults (BC6RR and RS) was 37 weeks; the mean life span of virgin, susceptible adults (SS and GV) was 32 weeks. Resistant virgin adults lived significantly longer (15-16%) than susceptible virgin adults, and mated resistant adults lived significantly longer (3-20%) than mated susceptible adults (p < .05). Since C. ferrugineus has a relatively long reproductive period and females with the longest life spans produce the most offspring, life span can be considered an important component of fitness in this insect. The malathion resistance gene did not reduce fitness, and this gene or genes closely linked to it may be responsible for increasing life span in C. ferrugineus.

Animals↗
PubMed1995

Method for cohort and nested case-control studies: the prevalence, timing and effectiveness of obstetric ultrasound, Victoria 1991-1992.

The study was designed to assess the effectiveness of obstetric ultrasound in the diagnosis of congenital malformations and to establish its prevalence of use and timing. Statewide data were collected in 138 of the 141 obstetric hospitals in Victoria over a 12-month period during 1991-1992. Within the final cohort of 55,226 mothers providing responses, a nested case-control study group was formed. This group comprised 719 cases (infants born with one or more malformations potentially diagnosable at 16-20 weeks) and 703 controls (non-malformed infants). The cases for the group were extracted from the Victorian Congenital Malformations Register; controls were randomly selected from the Victorian Perinatal Data Collection Unit's database. Of the 1422 in the study group, 1328 medical records were validated in 100 hospitals. The design, method, procedure, sample and outcome are described for the cohort and nested case-control studies. At the conclusion of the study it was established that major variations between the cohort and missing data were confined to mothers less likely to have had a spontaneous vaginal delivery or to those with poor perinatal outcome. There was no significant selective loss of cases or controls in the nested case-control study group.

Case-Control Studies↗
PubMed1995

The effect of vigorous exercise during pregnancy on birth-weight.

The aim of this study was to assess the effect on birth-weight of continuing a programme of vigorous exercise into late pregnancy. 'Potential exercisers' were women who had been doing vigorous exercise prior to pregnancy and intended to continue exercising during pregnancy. Controls were healthy pregnant women who did not do regular vigorous exercise. Both groups kept 2, 7-day food +/- exercise diaries at 25 and 35 weeks. The primary outcome variable was birth-weight. Women who continued doing at least 30 minutes of vigorous exercise at least 3 times weekly at 25 weeks and either maintained this minimum level or had delivered by 35 weeks were classified as 'exercisers'. Women doing more than 4 sessions of vigorous exercise weekly at 25 weeks had babies whose mean birth-weight was 315 g lower than the mean birth-weight of babies born to controls.

Adult↗
PubMed1995

The prevalence and timing of obstetric ultrasound in Victoria 1991-1992: a population-based study.

A statewide study to ascertain the number of ultrasound scans received by women in pregnancy, to identify the proportion having a scan at 16 to 20 weeks' gestation, and to establish where the scan at 16 to 20 weeks was performed was carried out between January, 1991 and June, 1992 in Victoria. Additional data were collected by midwives and entered on the perinatal morbidity statistics form routinely completed for all births. Of 52,319 women providing responses, 3.1% did not have a scan. Of the remaining 96.9% who had a scan, 73.5% were scanned at 16 to 20 weeks' gestation. Predictors of not having a scan were maternal birthplace and higher parity: previous perinatal death(s), and attendance at nonteaching hospitals predicted the opposite. Predictors of being scanned were location of hospital (country), maternal birthplace, higher parity and maternal age (< 20 years). Substantial differences in frequency and timing were found between hospitals attended. Factors associated with the pattern of scanning are not readily explicable in terms of risk of malformations or women's choices.

Adult↗
PubMed1994

Epidemiologic and immunologic characteristics of Streptococcus equi infection in foals.

A 2-phase study was performed to characterize the effects of Streptococcus equi infection in unexposed and previously exposed foals. In phase I, 22 weanling foals involved in a naturally occurring S equi epizootic were studied, along with a comparison group of 11 unexposed foals, matched for age, sex, and breed. Six months later (phase II), an epizootic was experimentally induced in previously exposed and unexposed foals from phase I. The prevalence and duration of clinical signs, the relative risk of developing disease, bacteriologic culture results, hematologic responses, and mucosal and serum immunologic responses were determined. Disease protection in phase-I and -II foals was associated with high values for serum S equi M protein-specific IgG at the onset of the epizootic (P < 0.02 for phase 1 and P < 0.01 for phase II), and with a rapid (within 2 weeks of exposure) mucosal S equi M protein-specific IgG response (P < 0.05 for phase I and P = 0.01 for phase II).

Analysis of Variance↗
PubMed1994

The vitamin A and vitamin E status of horses raised in Alberta and Saskatchewan.

The purpose of the study was to determine normal baseline levels of vitamin A and vitamin E in clinically normal horses under typical field conditions in Saskatchewan and Alberta. Heparinized blood samples were collected from approximately 400 clinically healthy horses selected from 24 locations in Alberta and Saskatchewan during a two-year period. For each horse, historical information including feed type, vitamin supplementation, time of year, sex, and age were recorded. From each blood sample, the plasma vitamin A (all-transretinol) and vitamin E (alpha-tocopherol) levels were measured using high pressure liquid chromatography. Normal baseline plasma vitamin A and vitamin E concentrations recorded during the study were 0.70 mumol/L and 7.65 mumol/L, respectively. The plasma vitamin concentrations were lower in the younger horses. The plasma vitamin levels were higher from May to August, as compared to other times of the year. Horses grazing fresh pasture exclusively during the summer months had plasma vitamin A and vitamin E concentrations that were 27% and 63% greater than horses fed harvested or stored feeds during the same time period. Sex-related differences were not evident in the study. A number of factors may influence the baseline plasma vitamin A and vitamin E levels in horses. Consequently, it is unadvisable to use a single evaluation to assess vitamin status. Multiple sampling from individual horses or sampling from many horses within a herd may reduce the variability and improve the ability to monitor vitamin status from plasma submissions.

Age Factors↗
PubMed1993

A randomized, double-blind, placebo-controlled trial of the safety of vaginal recombinant human relaxin for cervical ripening.

OBJECTIVE: To assess the safety of vaginal recombinant human relaxin in pregnant women treated before the induction of labor and to collect preliminary data on the efficacy of recombinant human relaxin in promoting cervical ripening. METHODS: In a multi-center, randomized, double-blind placebo-controlled trial, 40 women were studied before induction of labor because of post-dates. The women were randomized to receive either 1.5 mg recombinant human relaxin in 3% methylcellulose gel or gel only, placed into the posterior vaginal fornix after a cervical assessment on the evening before scheduled induction. If a subject did not go into spontaneous labor overnight, another cervical assessment was performed 15 hours following treatment, immediately before the standard induction regimen of the hospital. RESULTS: No important maternal or fetal-neonatal complications could be attributed to the drug. The differences between the recombinant human relaxin group and the placebo group for all the outcome measures of efficacy did not achieve statistical significance. Placebo patients were more likely to report moderate or strong uterine contractions in the first 4 hours following treatment than were the recombinant human relaxin-treated patients. CONCLUSIONS: The use of recombinant human relaxin at a dose of 1.5 mg was not associated with any significant maternal or fetal-neonatal complications. The relatively small number of subjects in this study was chosen deliberately because this was the first use of the drug in pregnant subjects. Assessment of efficacy will require studies that include more patients and a range of relaxin doses.

Administration, Intravaginal↗
PubMed1992

Antenatal uterine activity monitoring of women at increased risk of preterm labour.

The aim of the study was to investigate the usefulness of antenatal uterine activity monitoring in the management of women at increased risk of preterm labour on the basis of a past history of preterm birth or mid-trimester abortion. Uterine activity was recorded every 2 weeks between 20 and 28 weeks gestation. Activity was considered to be increased if pressure changes > 15 mmHg were detected. Fifty-eight women had uterine activity monitoring. Of them, 39 had normal uterine activity. Nineteen women had increased activity and they were randomized to either a study group (9) where the findings were revealed to the clinicians caring for them or a control group (10) where the findings were not revealed. There was no standard regimen of management for the study group except that additional uterine activity monitoring was performed to provide feed back to the clinicians about their interventions. The sensitivity, specificity, positive predictive value and negative predictive value of uterine activity monitoring for preterm births and for preterm births before 32 weeks were disappointing. Uterine activity monitoring was not useful for predicting births prior to 32 weeks; most of these were preceded by prelabour rupture of the membranes. The pregnancy outcome of women with increased uterine activity was not better if clinicians were aware of that increased activity than if they were not.

Female↗
PubMed1992

Pleuropulmonary paragonimiasis in a Laotian immigrant to Australia.

A case of pleuropulmonary paragonimiasis that mimicked reactivation of pulmonary tuberculosis, pneumonia, and neoplasm occurred in a Laotian immigrant to Australia. The key to the diagnosis of this condition is awareness of the disease in persons from this region. The diagnosis was supported by enzyme-linked immunosorbent assay testing. The patient was successfully treated with praziquantel.

Aged↗
PubMed1990

Idiopathic granulomatous disease involving the skin in a horse.

Clinical signs of generalized granulomatous disease in a horse included depression, generalized lymphadenopathy, scaly skin, and dependent edema. Diagnosis was confirmed histopathologically by diffuse granulomas in more than one organ system (lymph nodes and skin), and by ruling out etiologic agents. Response to treatment with corticosteroids was favorable. The clinical features and response to treatment in this horse were different from classic textbook descriptions of equine generalized granulomatous disease. Equine granulomatous disease appears to be comparable to human sarcoidosis. To avoid confusion between human medical and veterinary medical terminology, the authors suggest that the equine disease be referred to as equine idiopathic granulomatous disease and that a complete diagnostic description should include a reference to the organ systems involved.

Animals↗
PubMed1990

Relaxin in sera during the luteal phase of in-vitro fertilization cycles.

To identify the time when relaxin can first be detected in peripheral sera after in-vitro fertilization (IVF) and embryo transfer, blood samples were collected from 20 women up to 14 days after oocyte retrieval. Sixteen women did not become pregnant and in eight of them relaxin (but not beta-human chorionic gonadotrophin, beta-hCG) was measurable for the first time at days 6 to 12. Concentrations of other hormones measured were also different in these eight women compared with the remaining eight non-pregnant women; their serum concentrations of 17 alpha-OH progesterone, progesterone and oestradiol were higher but concentrations of luteinizing hormone and follicle-stimulating hormone were lower. Three women became pregnant; relaxin and beta-hCG were first detected on the same day (10 to 12). The remaining woman had increased beta-hCG levels but did not develop a clinical pregnancy. Measurement of serum relaxin during IVF cycles may allow assessment of corpora luteal function before its identification by levels of steroid hormones.

Chorionic Gonadotropin↗