Association of Streptococcus mutans Infection and Oral Developmental Nodules in Pre-dentate Infants

Since dental caries may present soon after tooth eruption, we hypothesized that colonization of Streptococcus mutans can occur in the predentate stages. In this study, we examined S. mutans colonization and its association with oral developmental nodules (Bohn's nodules) in 60 pre-term and 128 full-term, three-month-old infants. Overall, S. mutans was cultured from 30% (56/188) of the infants, and oral developmental nodules were noted in 55% (103/188). Compared with the pre-term, full-term infants showed a higher prevalence of S. mutans (34% vs. 20%, p < 0.02) as well as developmental nodules (61% vs. 42%, p < 0.05). In both groups, S. mutans was positively associated with numbers of developmental nodules in a dose-response relationship (p < 0,001), and with maternal salivary levels of the bacteria (p = 0.03). The permanence of S. mutans infection was confirmed by repeat saliva sampling at 6 months of age. Our results thus showed that many infants have already acquired S. mutans at 3 months of age, prior to tooth eruption.

Beyond sex and cooking: Health education for individuals with intellectual disability

Issues of health education programming for people with intellectual disability are discussed. As environments in which such individuals live become more inclusive, and they are encouraged to make their own choices, the issue of whether current health education is sufficient to enable them to make healthy life choices is considered. More attention should be focused on programs in schools and the community to fulfill this need. Three aspects of health education programming are considered: physical activity, general health knowledge, and social supports for health. Continuity of information is viewed as important in policy development as well as in interprofessional coordination and cooperation to assure that these individuals are not further handicapped by poor health.

Ni(II)-doped CsCdBrCl2: Variation of spectral and structural properties via mixed-halide coordination

A new addition to the family of single-molecule magnets is reported: an Fete cage stabilized with benzoate and pyridonate ligands. Monte Carlo methods have been used to derive exchange parameters within the cage, and hence model susceptibility behavior.

Cognitive behaviour therapy for the management of obsessive-compulsive disorder

Current research reflects conflict regarding best practice in the treatment of obsessive-compulsive disorder (OCD). The. present study reports on the psychological treatment of a 54-year-old woman diagnosed with OCD, and follows the implementation of pharmacological treatment. The study utilises both exposure and response prevention (ERP) and cognitive therapy (CT), although there was no attempt to compare these approaches in an experimental design. Measures of avoiding and neutralising behaviours were taken on three occasions across treatment. Measures were also taken of intrusive thoughts, appraisal of responsibility, and effective challenging, both across treatment and at follow-up. The results indicate that gains were made in addition to those reported following the implementation of medication. The results also suggest that the addition of CT to exposure and response prevention facilitates the extinction of neutralising behaviours.

A parent-completed developmental questionnaire: Follow up of ex-premature infants

Objective: premature infants are at increased risk of developmental disability. Early identification of problems allows intervention to ameliorate or attenuate problems. A reliable screening tool allows triage of children in this high-risk population by identifying those unlikely to need full developmental assessment. To explore the test characteristics of an established parent-completed developmental assessment questionnaire 'Ages and Stages Questionnaire' (ASQ) in follow up of an Australian population of premature infants. Methodology: One hundred and sixty-seven children born prematurely with corrected ages 12- to 48-months attending the Growth and Development Clinic at the Mater Children's Hospital in Brisbane, Queensland, Australia; 136 questionnaires 'ASQ' were returned completed (81%) and were compared to formal psychometric assessment (Griffith Mental Development Scales for 12- and 24-months, Bayley Mental Development Intelligence Scale for 18-months, McCarthy General Cognitive Intelligence Scale for 18-months). Developmental delay was considered to be present if any of the above psychometric assessments fell below 1.0 standard deviations (SD). The ASQ cut-off used was 2.0 SD (US data derived means and SD). Results: Aggregate results for all age groups comparing ASQ to psychometric assessments as 'gold standards' found the ASQ to have the following test characteristics: sensitivity (90%); specificity (77%); positive predictive value (40%); negative predictive value (98%): % over-referred (20%); % under-referred (1%); % agreement (79%). likelihood ratio for children failing the ASQ was 3.8 and for passing the ASQ was 0.13. Twenty-one children with known disabilities were included in the study and in 14 of these, the ASQ overall score agreed with the psychometric assessment (67%). Conclusion: The high negative predictive value of the ASQ supports its use as a screening tool for cognitive and motor delays in the follow up of ex-premature infants. This would need to be combined with other strategies as part of a comprehensive follow up program for ex-premature infants.

The acquisition of movement skills: Practice enhances the dynamic stability of bimanual coordination

During bimanual movements, two relatively stable inherent patterns of coordination (in-phase and anti-phase) are displayed (e.g., Kelso, Am. J. Physiol. 246 (1984) R1000). Recent research has shown that new patterns of coordination can be learned. For example, following practice a 90 degrees out-of-phase pattern can emerge as an additional, relatively stable, state (e.g., Zanone & Kelso, J. Exp. Psychol.: Human Performance and Perception 18 (1992) 403). On this basis, it has been concluded that practice leads to the evolution and stabilisation of the newly learned pattern and that this process of learning changes the entire attractor layout of the dynamic system. A general feature of such research has been to observe the changes of the targeted pattern's stability characteristics during training at a single movement frequency. The present study was designed to examine how practice affects the maintenance of a coordinated pattern as the movement frequency is scaled. Eleven volunteers were asked to perform a bimanual forearm pronation-supination task. Time to transition onset was used as an index of the subjects' ability to maintain two symmetrically opposite coordinated patterns (target task - 90 degrees out-of-phase - transfer task - 270 degrees out-of-phase). Their ability to maintain the target task and the transfer task were examined again after five practice sessions each consisting of 15 trials of only the 90 degrees out-of-phase pattern. Concurrent performance feedback (a Lissajous figure) was available to the participants during each practice trial. A comparison of the time to transition onset showed that the target task was more stable after practice (p = 0.025). These changes were still observed one week (p = 0.05) and two months (p = 0.075) after the practice period. Changes in the stability of the transfer task were not observed until two months after practice (p = 0.025). Notably, following practice, transitions from the 90 degrees pattern were generally to the anti-phase (180 degrees) pattern, whereas, transitions from the 270 degrees pattern were to the 90 degrees pattern. These results suggest that practice does improve the stability of a 90 degrees pattern, and that such improvements are transferable to the performance of the unpractised 270 degrees pattern. In addition, the anti-phase pattern remained more stable than the practised 90 degrees pattern throughout. (C) 2001 Elsevier Science B.V. All rights reserved.

Haptic information stabilizes and destabilizes coordination dynamics

Goal-directed, coordinated movements in humans emerge from a variety of constraints that range from 'high-level' cognitive strategies based oil perception of the task to 'low-level' neuromuscular-skeletal factors such as differential contributions to coordination from flexor and extensor muscles. There has been a tendency in the literature to dichotomize these sources of constraint, favouring one or the other rather than recognizing and understanding their mutual interplay. In this experiment, subjects were required to coordinate rhythmic flexion and extension movements with an auditory metronome, the rate of which was systematically increased. When subjects started in extension on the beat of the metronome, there was a small tendency to switch to flexion at higher rates, but not vice versa. When subjects: were asked to contact a physical stop, the location of which was either coincident with or counterphase to the auditor) stimulus, two effects occurred. When haptic contact was coincident with sound, coordination was stabilized for both flexion and extension. When haptic contact was counterphase to the metronome, coordination was actually destabilized, with transitions occurring from both extension to flexion on the beat and from flexion to extension on the beat. These results reveal the complementary nature of strategic and neuromuscular factors in sensorimotor coordination. They also suggest the presence of a multimodal neural integration process-which is parametrizable by rate and context - in which intentional movement, touch and sound are bound into a single, coherent unit.

Let your feet do the walking: constraints on the stability of bipedal coordination

In this paper we consider whether the behaviour of the neural circuitry that controls lower limb movements in humans is shaped primarily by the spatiotemporal characteristics of bipedal gait patterns, or by selective pressures that are sensitive to considerations of balance and energetics. During the course of normal locomotion, the full dynamics of the neural circuitry are masked by the inertial properties of the limbs. In the present study, participants executed bipedal movements in conditions in which their feet were either unloaded or subject to additional inertial loads. Two patterns of rhythmic coordination were examined. In the in-phase mode, participants were required to flex their ankles and extend their ankles in synchrony. In the out-of-phase mode, the participants flexed one ankle while extending the other and vice versa. The frequency of movement was increased systematically throughout each experimental trial. All participants were able to maintain both the in-phase and the out-of-phase mode of coordination, to the point at which they could no longer increase their frequency of movement. Transitions between the two modes were not observed, and the stability of the out-of-phase and in-phase modes of coordination was equivalent at all movement frequencies. These findings indicate that, in humans, the behaviour of the neural circuitry underlying coordinated movements of the lower limbs is not constrained strongly by the spatiotemporal symmetries of bipedal gait patterns.