Search PubMed⌕ Search

Biomedical subjects

T Nolan

Publications and source records attributed to T Nolan.

At least 55 records · Page 3Linked to original sources

Randomised controlled trial of biofeedback training in persistent encopresis with anismus.

BACKGROUND: Paradoxical external anal sphincter contraction during attempted defecation (anismus) is thought to be an important contributor to chronic faecal retention and encopresis in children. Biofeedback training can be used to teach children to abolish this abnormal contraction. METHODS: A randomised controlled trial in medical treatment resistant and/or treatment dependent children with anismus using surface electromyographic (EMG) biofeedback training to determine whether such training produces sustained faecal continence. Up to four sessions of biofeedback training were conducted at weekly intervals for each patient. Anorectal manometry was performed before randomisation and six months later. Parents of patients completed the "child behaviour checklist" (CBCL) before randomisation and at follow up. RESULTS: Sixty eight children underwent anorectal manometry and EMG. Of these, 29 had anismus (ages 4-14 years) and were randomised to either EMG biofeedback training and conventional medical treatment (BFT) (n = 14) or to conventional medical treatment alone (n = 15). All but one child were able to learn relaxation of the external anal sphincter on attempted defecation. At six months' follow up, laxative free remission had been sustained in two of 14 patients in the BFT group and in two of 15 controls (95% confidence interval (CI) on difference, -24% to 26%). Remission or improvement occurred in four of 14 patients in the BFT group and six of 15 controls (95% CI on difference, -46% to 23%). Of subjects available for repeat anorectal manometry and EMG at six months, six of 13 in the BFT group still demonstrated anismus v 11 of 13 controls (95% CI on difference, -75% to -1%). Of the four patients in full remission at six months, only one (in the BFT group) did not exhibit anismus. Rectal hyposensitivity was not associated with remission or improvement in either of the groups. Mean CBCL total behaviour problem scores were not significantly different between the BFT and control groups, but there was a significant improvement in CBCL school scale scores in the BFT group, and this improvement was significantly greater than that seen in the control group. CONCLUSIONS: The result of this study, together with those reported in other controlled trials, argues against using biofeedback training in children with encopresis.

Adolescent↗

School based bicycle safety education and bicycle injuries in children: a case-control study.

OBJECTIVES: To evaluate possible benefits of a school based bicycle safety education program ("Bike Ed") on the risk of bicycle injury in children. METHODS: A population based case-control study was undertaken in a region of Melbourne, Australia. Cases were children presenting at hospital emergency departments with injuries received while riding bicycles. Controls were recruited by calling randomly selected telephone numbers. Data were collected by personal interview. RESULTS: Analysis, based on 148 cases and 130 controls aged 9 to 14 years, showed no evidence of a protective effect and suggested a possible harmful effect of exposure to the bicycle safety course (odds ratio (OR) 1.64, 95% confidence interval (CI) 0.98 to 2.75). This association was not substantially altered by adjustment for sex, age, socioeconomic status, and exposure, measured as time or distance travelled. Subgroup analysis indicated that the association was strongest in boys (OR 2.0, 95% CI 1.1 to 3.8), younger children, children from families with lower parental education levels, and children lacking other family members who bicycle. CONCLUSIONS: It is concluded that this educational intervention does not reduce the risk of bicycle injury in children and may possibly produce harmful effects in some children, perhaps due to inadvertent encouragement of risk taking or of bicycling with inadequate supervision.

Case-Control Studies↗

Pragmatic science: accelerating the improvement of critical care.

Adapting practices that are described in the literature or used effectively in other critical care units provides an opportunity to improve the quality of critical care and reduce costs. Described in the literature are different techniques for the gradual withdrawal of mechanical ventilator support from patients during weaning from the ventilator. Phoebe Putney Memorial Hospital in Albany, GA used a systematic approach to adapt these techniques to improve the weaning process. This resulted in a reduction in the number of days patients were on a ventilator and a reduction in the ICU length of stay for patients with acute respiratory failure requiring mechanical ventilation.

Clinical Protocols↗

Paediatric slow-speed non-traffic fatalities: Victoria, Australia, 1985-1995.

An important group of fatal incidents are slow-speed pedestrian non-traffic incidents to children, which account for 14% of accidental deaths from all causes in Victorian children under 5 years of age between 1985 and 1995, and 12% of pedestrian deaths of all ages. In Victoria, Australia, the database of the state Consultative Council on Obstetric and Paediatric Morbidity and Mortality was utilised to identify paediatric slow-speed pedestrian non-traffic-accident deaths in the local population. Additional data relating to the car and its driver, the child, and the circumstances of the incident were abstracted from records kept by the State Coroner and the Victorian compulsory third party traffic injury insurance organisation. Twenty eight Victorian children were identified who had died in one of three types of incident (driverless cars, child interacting with the vehicle and driver, and drivers who were unaware of the child's proximity). These incidents were more common in rural areas compared with urban, usually occurring at the child's home. The child was with or near an adult on all occasions. The vehicle was usually being driven by a relative, and was reversing in a higher proportion of 'unaware' incidents compared with the 'interactive' type. The association of 'off-road' family vehicles and trucks with these incidents appears to be increasing, especially in recent years. These findings suggest some countermeasures, including the separation of vehicle driveways from children's play areas, and object vicinity ultrasonic warning devices for vehicles.

Accidents, Home↗

Primary course immunogenicity and reactogenicity of a new diphtheria-tetanus-whole cell pertussis vaccine (DTPw).

OBJECTIVE: To establish safety, immunogenicity, and batch stability of a reformulated whole cell pertussis based diphtheriatetanus-whole cell pertussis (DTP) vaccine (nDTPw) compared to the currently marketed Australian DTPw vaccine (Triple Antigen) in a three dose 2, 4 and 6 month primary immunization course. Reformulation was necessary to make the DTPw vaccine suitable for combination with hepatitis B and Haemophilus influenzae b vaccines. METHODS: Double blind randomized controlled trial in suburban Melbourne in 812 healthy infants recruited through maternal and child health centres, of whom 208 received Triple Antigen and 604 received nDTPw. RESULTS: Results for both reactogenicity and immunogenicity were similar and were not significantly different for the three batches of nDTPw. No new, serious, or unexpected adverse effect was recorded. Nearly twice as many nDTPw infants experienced no general reaction to the third dose (18%) compared to Triple Antigen (11%, P = 0.06). An elevated temperature (> or = 38 degrees C axillary) occurred in about three out of 10 babies overall, with rates being slightly higher for both vaccines after the second vaccination. Local reaction rates were significantly less common for nDTPw on days 2 and 3 following each of the three vaccinations. After dose three, 30% of nDTPw subjects experienced no local reaction compared to 20% of Triple Antigen subjects (P = 0.015, 95% Cl on difference 2%, 19%). Swelling after doses one and three occurred in 30% and 24% of Triple Antigen subjects, compared to 23% (P = 0.07, 95% Cl diff 0%, 13%) and 14% (P = 0.017, 95% Cl diff 2%, 17%) of nDTPw subjects. Tenderness after doses two and three occurred in 80%, and 78% of Triple Antigen subjects, compared to 71% (P = 0.04, 95% Cl diff 1%, 17%) and 68% (P = 0.025, 95% Cl diff 2%, 19%) of nDTPw subjects. There was a significantly higher post immunization diphtheria antitoxin GMT (2.73 IU/mL) for Triple Antigen compared to nDTPw (1.89 IU/mL; P = 0.02), although no subject in either vaccine group had a tetanus or diphtheria antibody titre less than six times the protective level of 0.01 IU/mL following immunization. The nDTPw post immunization GMTs were significantly higher for Agg2, Fha, and pertactin compared to Triple Antigen geometric mean titres (GMTs). CONCLUSION: nDTPw is a safe and immunogenic vaccine when compared to Triple Antigen. The reformulated vaccine is an acceptable replacement for the currently marketed formulation, and for evaluation as a component of future combination vaccines.

Antibody Formation↗

Walking to school and traffic exposure in Australian children.

Daily patterns of pedestrian activity in young children have important health implications, primarily because of the risk of road traffic injury, but also because they may reflect the commencement of exercise habits with long-term consequences. A cross-sectional survey in two Australian cities, Melbourne and Perth, aimed to collect, by parent self-administered questionnaire, population-based data on modes of travel, numbers of street crossings (both accompanied and unaccompanied by an adult), and sociodemographic factors for six- and nine-year-old children. Results indicate that 35 per cent (95 per cent confidence interval (CI) 31 to 39 per cent) and 31 per cent (CI 28 to 34 per cent) walk to school in Melbourne and Perth respectively, while over 60 per cent are driven to school by car, with very small proportions riding bicycles or taking public transport. A higher level of walking was associated with lower levels of several indicators of socioeconomic status. Logistic regression analysis showed that the strongest predictor of walking activity was school type (government versus independent), and after adjusting for this, lesser car ownership, non-English-speaking background and lower occupational category were associated with walking to school, while a different set of predictors--age, sex and maternal education--was associated with the unaccompanied crossing of streets. There was little difference in overall walking levels between boys and girls, but boys were significantly more likely to cross streets unaccompanied (adjusted odds ratio 1.41, CI 1.14 to 1.72), providing a partial explanation of documented sex differences in injury rates.

Accidents, Traffic↗

An international study of the exposure of children to traffic.

OBJECTIVES: To examine the extent of international differences in children's exposure to traffic as pedestrians or bicyclists. DESIGN: Children's travel patterns were surveyed using a parent-child administered questionnaire. Children were sampled via primary schools, using a probability cluster sampling design. SETTING: Six cities in five countries: Melbourne and Perth (Australia), Montreal (Canada), Auckland (New Zealand), Umeå (Sweden), and Baltimore (USA). SUBJECTS: Children aged 6 and 9 years. MAIN OUTCOME MEASURES: Modes of travel on the school-home journey, total daily time spent walking, and the average daily number of roads crossed. MAIN FINDINGS: Responses were obtained from the parents of 13423 children. There are distinct patterns of children's travel in the six cities studied. Children's travel in the three Australasian cities, Melbourne, Perth and Auckland, is characterised by high car use, low levels of bicycling, and a steep decline in walking with increasing car ownership. In these cities, over a third of the children sampled spent less than five minutes walking per day. In Montreal, walking and public transport were the most common modes of travel. In Umeå, walking and bicycling predominated, with very low use of motorised transport. In comparison with children in the Australasian and North American cities, children in Umeå spend more time walking, with 87% of children walking for more than five minutes per day. CONCLUSIONS: There are large international differences in the extent to which children walk and cycle. These findings would suggest that differences in 'exposure to risk' may be an important contributor to international differences in pedestrian injury rates. There are also substantial differences in pedestrian exposure to risk by levels of car ownership-differences that may explain socioeconomic differentials in pedestrian injury rates.

Australia↗

Vascular and hemodynamic differences between organic nitrates and nitrites.

Because nitroglycerin (NTG, an organic nitrate) and isoamyl nitrite have similar chemical structures and a common mechanism of vascular relaxation (i.e., conversion to nitric oxide in vascular tissues and activation of guanylyl cyclase), it has often been assumed that organic nitrates and nitrites have identical pharmacologic actions. Because recent studies have shown that the vascular enzymes responsible for nitric oxide generation from organic nitrates and nitrites are distinct, we hypothesized that the in vitro vascular actions, in vivo hemodynamic effects and tolerance properties (both in vitro and in vivo) would be different as well. Isolated blood vessel studies showed that NTG provided more stable relaxation effects than ISAN, was more potent and caused greater in vitro vascular tolerance. Because the mechanism(s) of vascular tolerance in vitro may not be the same as those occurring in vivo, we also compared the left ventricular hemodynamic effects and tolerance properties of NTG vs. isoamyl nitrite and in congestive heart failure rats. Constant NTG infusion (10 micrograms/min) caused initial reductions in left ventricular end-diastolic pressure of 45 to 55%, which returned to baseline within 10 hr (tolerance development). In contrast, isobutyl nitrite and isoamyl nitrite (45 micrograms/min) caused initial reductions in left ventricular end-diastolic pressure similar to NTG (42-58%), but these hemodynamic effects of organic nitrites were maintained even when infusions were carried out to 22 hr. These results show that organic nitrites and organic nitrates are not pharmacologically identical (in vitro or in vivo), and may suggest a therapeutic advantage for organic nitrites in the treatment of some cardiovascular diseases.

Amyl Nitrite↗

Childhood bacterial meningitis: impact of age at illness and acute medical complications on long term outcome.

This study compared postmeningitic children (N = 130) with grade and sex matched controls (N = 130) selected from target children's schools on measures of intellectual, linguistic, learning, and reading skills. Results showed that children with a history of meningitis are at greater risk for impairment in these areas, with experience of the disease prior to 12 months of age being an important risk factor. Within the postmeningitic sample presence of medical complications was associated with poorer verbal abilities. Finally, a significant relationship was identified between depressed language skills and later educational difficulty, with these findings interpreted with respect to both developmental and neuropsychological principles.

Adolescent↗

Isolation and molecular characterisation of the POL3 gene from Candida albicans.

In Saccharomyces cerevisiae, the CDC2 gene encodes the large subunit of DNA polymerase III, the analogue of mammalian DNA polymerase delta. We have isolated DNA fragments from a library of Candida albicans genomic DNA in the vector pRS316 that rescue temperature sensitive cdc2 mutations in S. cerevisiae. These fragments contain an ORF coding for a protein of 1038 aa with a predicted molecular mass of 118.8 kDa. The predicted protein shows homology to a number of eukaryotic DNA polymerases, with 62% identity over its length to the S. cerevisiae Cdc2 protein. It also contains a number of motifs which are characteristic of DNA polymerases in general and viral polymerases in particular, as well as the conserved motif which interacts with proliferating cell nuclear antigen. These results indicate that this gene is C. albicans POL3. Analysis of the expression of C. albicans POL3 revealed that the transcript is present throughout the mitotic cell cycle, which contrasts with the expression of S. cerevisiae CDC2.

Amino Acid Sequence↗

A comparison of two column agglutination technologies for routine antibody screening using the indirect antiglobulin technique.

Two commercial column agglutination technologies were compared for routine antibody screening using the indirect antiglobulin technique with 1000 heparinised blood samples from a general hospital. The I.D. microtyping system (Diamed) utilises a Sephadex gel, and the Biovue system (Ortho Diagnostics) consists of a column containing minute glass beads. Both systems have antihuman globulin incorporated into them resulting in agglutinates being trapped and allowing free red cells to pass through to the base. The purpose of this study was to compare the two technologies with the minimum amount of variables possible. The spin tube antiglobulin technique was not included in this study as this technology has not been used in this laboratory since January 1991. The systems compared well, despite different serological problems.

Blood Grouping and Crossmatching↗

A case-control study of child bicycle injuries: relationship of risk to exposure.

In order to assess the relationship of the risk of injury requiring hospital attendance in children riding bicycles to sociodemographic factors and to measures of exposure, a population-based case-control study is being undertaken in a large area of suburban Melbourne, Australia. Particular attention is given to the measurement of individual exposure in several dimensions. Analysis of interim data from 109 cases and 118 controls shows that 51% of injuries occurred while the child was playing rather than making a trip on the bicycle and only 22% involved another vehicle. Boys used bicycles more commonly than girls but there was minimal evidence of an increased risk of injury in boys, adjusting for exposure. There was no evidence for an age trend in injury risk, but children from families in the lowest income category were at significantly increased risk. Exposure measures showed complex patterns of association with injury risk. Estimated time spent riding was more closely associated with risk than distance travelled, with an odds ratio of 2.2 (95% confidence interval 1.1-4.2) for children riding for more than 3 hours per week compared to children riding less than 1 hour. Riding more than 5 km on the sidewalk was also associated with increased risk (odds ratio 3.1, 95% CI 1.1-8.5). The elevated risk associated with sidewalk riding may be due to difficulties in negotiating uneven surfaces. The case-control study provides an ideal design for this type of investigation but valid and reliable measurement of exposure is difficult.

Accidents, Traffic↗

The influence of the site of parasite inoculation on the development of Th1 and Th2 type immune responses in (BALB/c x C57BL/6) F1 mice infected with Leishmania major.

Although inbred strains of mice are classified as genetically resistant or susceptible to Leishmania major based upon their ability to control infection, other factors such as the strain, dose, and site of parasite inoculation can also affect the outcome of the disease. Here we used the F1 progeny of BALB/c (susceptible) and C57BL/6 (resistant) mice (designated CB6F1) to investigate whether mice or intermediate susceptibility to infection differed from the parental strains in their ability to control infections at different cutaneous sites. CB6F1 mice developed progressive disease when inoculated in the dorsal skin, but healed infections in the footpad. Consistent with these observations, mice inoculated in the footpad ultimately developed Th1 responses, known to be required for healing, while Th2 responses developed in mice inoculated in the dorsal skin. However, IL-4 and IFN-gamma production during the first few weeks of infection was similar in CB6F1 mice inoculated at either site, suggesting that factors in addition to the relative levels of these cytokines produced early in infection may influence the nature of the antileishmanial immune response, and the eventual disease outcome. Infection in CB6F1 mice provides a model for the study of immunity to L. major in genetically identical animals, in which a prolonged mixed Th1/Th2 cytokine pattern initially develops, but ultimately diverges into more defined Th1 and Th2 type responses.

Animals↗

Clinical signs associated with Triple Antigen (DTP) vaccination in infants.

OBJECTIVE: The perceived reactogenicity of pertussis-containing vaccines is of considerable public health importance. The purpose of this study was to establish prospectively the incidence of systemic and local clinical signs associated with the first three doses of the diphtheria-tetanus-pertussis vaccine (DTP) currently used in Australia. In addition, in order to determine whether variability in reporting of such phenomena might be associated with variation in DTP batches, infant behaviour was studied with three batches for the first of the three DTP vaccinations. METHODOLOGY: Double blind, randomized controlled trial. There were 591 eligible infants who were recruited sequentially from centres for vaccination in three large Melbourne municipalities, of whom 531 (mean age 10 weeks, 45% female) were randomized and immunized. Of 181 subjects who received DTP from batch 1, 151 were studied at the time of their second DTP dose, and 98 at the third. Infants were assigned randomly to receive one of three batches of DTP vaccine. Parents were provided with a thermometer and a clinical sign diary. Research nurses visited the home 24 h after vaccination, and telephoned 7 days after vaccination to record local and systemic signs. RESULTS: There was no significant variation between DTP batches in rates of local or systemic signs. At the time of the first vaccination, the rates of local signs were: redness 16%, induration 29%, swelling 46%, and tenderness 54%. Systemic signs included: irritability 93%, intermittent inconsolable crying 43%, and persistent crying 12%. An axillary temperature of greater than 38 degrees C was recorded in 13% (CI 9-19%) of babies following the first immunization, 20% (CI 14-27%) following the second, and 14% (CI 8-23%) following the third immunization. There were significant reductions in the rates of observed signs over the immunization course for diarrhoea, irritability, intermittent inconsolable crying and persistent crying. CONCLUSIONS: There is little difference in the rates of clinical signs or presumed minor adverse effects associated with the DTP vaccine used in Australia today compared to that used 10 years ago, despite increases in the diphtheria and tetanus toxoid concentration, and the addition of aluminium phosphate adjuvant. Rates are comparable to those for other DTP vaccines manufactured in North America and Europe.

Diphtheria-Tetanus-Pertussis Vaccine↗