Energy utilization associated with regular activity breaks and continuous physical activity: A randomized crossover trial.

AIMS: To quantify and compare energy utilization associated with prolonged sitting alone, or interrupted with regular activity breaks and/or an additional bout of continuous physical activity. METHODS AND RESULTS: Thirty six adults (11 males, BMI 24.1 ± 4.6) completed four interventions: (1) prolonged sitting (SIT), (2) sitting with 2-min of walking every 30 min (RAB), (3) prolonged sitting with 30-min of continuous walking at the end of the day (SIT + PA), (4) a combination of the activities in (2) and (3) above (RAB + PA). All walking was at a speed and incline corresponding to 60% V̇O2max. Energy utilization over 7 h for each intervention was estimated using indirect calorimetry. Compared to SIT, SIT + PA increased total energy utilization by 709 kJ (95% CI 485-933 kJ), RAB by 863 kJ (95% CI 638-1088 kJ), and RAB + PA by 1752 kJ (95% CI 1527-1927 kJ) (all p < 0.001). There was no difference in total energy utilization between SIT + PA and RAB, however, post-physical activity energy utilization in RAB was 632 kJ greater than SIT + PA (95% CI 561-704 kJ; p < 0.001). CONCLUSIONS: Short frequent activity, results in greater accumulation of elevated post-physical activity energy utilization compared to a single bout of continuous activity; however the total energy utilization is similar. Combining activity breaks with a longer continuous bout of activity will further enhance energy utilization, and in the longer term, may positively affect weight management of a greater magnitude than either activity pattern performed alone. TRIAL REGISTRATION: ANZCTR12614000624684.

Determination of the glycaemic index of foods: interlaboratory study.

OBJECTIVE: Practical use of the glycaemic index (GI), as recommended by the FAO/WHO, requires an evaluation of the recommended method. Our purpose was to determine the magnitude and sources of variation of the GI values obtained by experienced investigators in different international centres. DESIGN: GI values of four centrally provided foods (instant potato, rice, spaghetti and barley) and locally obtained white bread were determined in 8-12 subjects in each of seven centres using the method recommended by FAO/WHO. Data analysis was performed centrally. SETTING: University departments of nutrition. SUBJECTS: Healthy subjects (28 male, 40 female) were studied. RESULTS: The GI values of the five foods did not vary significantly in different centres nor was there a significant centrexfood interaction. Within-subject variation from two centres using venous blood was twice that from five centres using capillary blood. The s.d. of centre mean GI values was reduced from 10.6 (range 6.8-12.8) to 9.0 (range 4.8-12.6) by excluding venous blood data. GI values were not significantly related to differences in method of glucose measurement or subject characteristics (age, sex, BMI, ethnicity or absolute glycaemic response). GI values for locally obtained bread were no more variable than those for centrally provided foods. CONCLUSIONS: The GI values of foods are more precisely determined using capillary than venous blood sampling, with mean between-laboratory s.d. of approximately 9.0. Finding ways to reduce within-subject variation of glycaemic responses may be the most effective strategy to improve the precision of measurement of GI values.

Smoking cessation - the role of the dental team implications for the Caribbean [abstract]

There is increasing awareness that cigarette smoking not only threatens systemic health but also compromises oral health. For example, smoking can result in staining of teeth, halitosis (bad breath), altered salivary flow, predisposition to chronic and acute periodontal disease and oral candidosis, delayed wound healing, failure of dental implants, oral mucosal lesions, oral precancer and cancer. Although data from the United Kingdom show a reduction in the prevalence of smoking since the 1960s, there is an upward trend of smoking among young adults, particularly teenage girls. There are no comparable data for the Caribbean but it is plausible to assume a similar trend may exist, suggesting the need for primary prevention strategies. The dental team often treats patients in a primary care setting and, apart from an important role in early detection of smoking-related oral conditions, may also be well placed to aid in preventive strategies through the implementation of chair-side smoking cessation programmes. These programmes are based on the 4-As strategy: Ask, Advise, Assist, Arrange, and have been recently developed specifically for the dental team. There should also be close collaboration between the dental team and other primary health care professionals to improve health promotion strategies aimed at reducing the prevalence of smoking. Dental health professionals in the Caribbean must be made aware of smoking cessation programmes for their patients and research into their effectiveness, in a Caribbean population, is required. (AU)

Comparison of the oscillometric blood pressure monitor (BPM-100(Beta) ) with the auscultatory mercury sphygmomanometer.

BACKGROUND: To compare directly the accuracy of the BPM-100(Beta) monitor (an automated oscillometric blood pressure device) with standard auscultatory mercury sphygmomanometry. DESIGN: The BPM-100(Beta) was connected in parallel via a T-tube to a mercury sphygmomanometer. The BPM-100(Beta) and two trained observers (blinded from each other and from the BPM-100(Beta)) measured the sitting blood pressure simultaneously. METHODS: Means, standard deviations and ranges were calculated for all the demographic data: age, arm size, heart rate and blood pressure. The agreement between the BPM-100(Beta) and the mean of two observers (the reference) was determined and expressed as the mean +/- SD, as well as the percentage of differences falling within 5, 10 and 15 mmHg. RESULTS: Of the 92 subjects recruited, 85 (92.4%) met the inclusion criteria, and 391 sets of sitting blood pressure and heart rate measurements were available for analysis. The mean difference between the BPM-100(Beta) monitor and the reference was -0.62 +/- 6.96 mmHg for systolic blood pressure, -1.48 +/- 4.80 mmHg for diastolic blood pressure and 0.14 +/- 1.86 beats/min for heart rate. The only limitation of the device was its tendency to underestimate higher systolic blood pressures. This problem has been addressed by a minor change in the algorithm (see the companion publication, Blood Press Monit, 6, 161-165, 2001). CONCLUSION: The BPM-100(Beta) is an accurate blood pressure monitor for the office setting, meeting all requirements of the Association for the Advancement of Medical Instrumentation and achieving an 'A' grade according to the British Hypertension Society protocol.

Validation of a new algorithm for the BPM-100 electronic oscillometric office blood pressure monitor.

BACKGROUND: To test the accuracy of a new algorithm for the BPM-100, an automated oscillometric blood pressure (BP) monitor, using stored data from an independently conducted validation trial comparing the BPM-100(Beta) with a mercury sphygmomanometer. DESIGN: Raw pulse wave and cuff pressure data were stored electronically using embedded software in the BPM-100(Beta), during the validation trial. The 391 sets of measurements were separated objectively into two subsets. A subset of 136 measurements was used to develop a new algorithm to enhance the accuracy of the device when reading higher systolic pressures. The larger subset of 255 measurements (three readings for 85 subjects) was used as test data to validate the accuracy of the new algorithm. METHODS: Differences between the new algorithm BPM-100 and the reference (mean of two observers) were determined and expressed as the mean difference +/- SD, plus the percentage of measurements within 5, 10, and 15 mmHg. RESULTS: The mean difference between the BPM-100 and reference systolic BP was -0.16 +/- 5.13 mmHg, with 73.7% < or = 5 mmHg, 94.9% < or = 10 mmHg and 98.8% < or = 15 mmHg. The mean difference between the BPM-100 and reference diastolic BP was -1.41 +/- 4.67 mmHg, with 78.4% < or = 5 mmHg, 92.5% < or = 10 mmHg, and 99.2% < or = 15 mmHg. These data improve upon that of the BPM-100(Beta) and pass the AAMI standard, and 'A' grade BHS protocol. CONCLUSION: This study illustrates a new method for developing and testing a change in an algorithm for an oscillometric BP monitor utilizing collected and stored electronic data and demonstrates that the new algorithm meets the AAMI standard and BHS protocol.

The acoustic bases for gender identification from children's voices.

The purpose of this study was to examine the acoustic characteristics of children's speech and voices that account for listeners' ability to identify gender. In Experiment I, vocal recordings and gross physical measurements of 4-, 8-, 12-, and 16-year olds were taken (10 girls and 10 boys per age group). The speech sample consisted of seven nondiphthongal vowels of American English (/ae/ "had," /E/ "head," /i/ "heed," /I/ "hid," /a/ "hod," /inverted v/ "hud," and /u/ "who'd") produced in the carrier phrase, "Say /hVd/ again." Fundamental frequency (f0) and formant frequencies (F1, F2, F3) were measured from these syllables. In Experiment II, 20 adults rated the syllables produced by the children in Experiment I based on a six-point gender rating scale. The results from these experiments indicate (1) vowel formant frequencies differentiate gender for children as young as four years of age, while formant frequencies and f0 differentiate gender after 12 years of age, (2) the relationship between gross measures of physical size and vocal characteristics is apparent for at least 12- and 16-year olds, and (3) listeners can identify gender from the speech and voice of children as young as four years of age, and with respect to young children, listeners appear to base their gender ratings on vowel formant frequencies. The findings are discussed in relation to the development of gender identity and its perceptual representation in speech and voice.

Debromosceptrin, an alkaloid from the Caribbean sponge Agelas conifera.

As the result of a structurally guided isolation to identify lead compounds for the treatment of opportunistic infections of AIDS, the dihydrochloride salt of a new symmetrical pyrrole dimer debromosceptrin (1), and two known pyrrole analogues (2 and 3) were isolated from the Caribbean sponge Agelas coniferacollected from Belize. The structure of debromosceptrin was identified by analysis of spectral data. 15N spectral data assignments were made for compounds 1-3. Compounds 2 and 3 showed marginal inhibition of Mycobacterium tuberculosis.

Debromosceptrin, an alkaloid from the Caribbean sponge Agelas conifera

As the result of a structurally guided isolation to identify lead compounds for the treatment of opportunistic infections of AIDS, the dihydrochloride salt of a new symmetrical pyrrole analogues (2 and 3) were isolated from the Caribbean sponge Agelas conifera collected from Belize. The structure of debromosceptrin was identified by analysis of spectral data. 15N spectral data assignments were made for compounds 1-3. Compounds 2 and 3 showed marginal inhibition of Mycobacterium tuberculosis (Au)

Lifestyle intervention in people with insulin-dependent diabetes mellitus (IDDM).

OBJECTIVE: To investigate the impact of intensive lifestyle education on dietary practices, exercise and metabolic measurements in people with insulin-dependent diabetes mellitus (IDDM). DESIGN: Sixty-one volunteer subjects with IDDM were randomised to intensive (Group 1) or standard (Group 2) education programmes for six months. During a second six month period of observation Group 1 subjects received routine surveillance for their condition and those in Group 2 were given intensive advice (phase 2). Current insulin regimens were modified to optimise glycaemic control before the start of the intervention phase. Nutrient intakes, weight, blood pressure, glycated haemoglobin (HbA1), plasma lipids, lipoproteins and maximal oxygen consumption (VO2 max) were measured at the time of recruitment and at three monthly intervals during the trial and phase 2. SETTING: Department of Human Nutrition at the University of Otago. RESULTS: Glycated haemoglobin decreased significantly in both groups between recruitment and randomisation, the improvement being sustained during the six months of the randomised trial and for group 1 during the six months of post trial observation. A further decrease was seen in Group 2 during the second six month period when they were given intensive advice. Comparable changes were seen with total and low density lipoprotein (LDL) cholesterol in Group 1 during the trial, but significant decreases were only seen in Group 2 in association with intensive intervention (phase 2). These changes occurred in parallel with increases in intakes of carbohydrate and monounsaturated fatty acids, a reduction in intakes of total and saturated fat, and an improvement in maximum oxygen consumption. CONCLUSIONS: A lifestyle programme for people with IDDM results in modest changes in diet and exercise habits sufficient to improve measures of glycaemic control and lipoprotein mediated risk of coronary heart disease independent of changes in insulin regime. More innovative approaches to achieve lifestyle changes are required to meet current recommendations which in turn are likely to produce even greater beneficial changes than those observed here.

Excitatory amino acid receptor antagonist in murine motoneuron disease (the wobbler mouse).

Recent evidence has suggested a potential role for involvement of excitatory amino acids (EAA) in the pathogenesis of the neuron loss in motoneuron diseases. We have examined the ability of an antagonist of N-methyl-D-aspartate (NMDA) receptors to halt or retard the progression of neurological symptoms in a murine form of motoneuron disease. The wobbler mouse is an autosomal recessive mutant which develops progressive neurological symptoms secondary to motoneuron loss. Treatment of wobbler mice with the NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)cyclohepten-5, 10-imine maleate (MK-801) did not retard neurological deterioration as assessed by a semiquantitative clinical scale. We conclude that NMDA receptor activation is probably not involved in the pathogenesis of motoneuron loss in the wobbler mouse.

Amyotrophic lateral sclerosis: interleukin-6 levels in cerebrospinal fluid.

Recent observations indicate that antibodies to gangliosides are found in many patients with amyotrophic lateral sclerosis (ALS). If antigen-antibody complexes occur in ALS, elevations of cytokine levels might be expected, among them the cytokine interleukin-6 (IL-6). IL-6 is secreted by activated monocytes and other cell types and is an important mediator of the inflammatory response. We have measured cerebrospinal fluid (CSF) IL-6 levels in patients with ALS and compared them with those in psychiatric and neurodegenerative disorders not believed to be due to immune disorders of the central nervous system. We found no significant differences in CSF IL-6 levels between these groups.

Partial protective effect of MK-801 on MPTP-induced reduction of striatal dopamine in mice.

The protective effect of MK-801, an N-methyl-D-aspartate (NMDA) receptor antagonist on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced reduction of striatal dopamine (DA) was examined in C57 BL/6 mice. Striatal DA levels were significantly higher in animals receiving parenteral MK-801 before and for 48 h following MPTP administration after 28 days than in animals receiving MPTP alone. The effect was not due to inhibition of monoamine oxidase-B (MAO-B) by MK-801. These data suggest that NMDA receptors may be involved in some of the neurotoxicity produced by MPTP.

The wobbler mouse: amino acid contents in brain and spinal cord.

Reductions in glutamate and aspartate contents, together with increased contents of taurine, have been observed in the autopsied brains and spinal cords of patients who have died with amyotrophic lateral sclerosis (ALS). The wobbler mouse develops an inherited degeneration of motoneurons within the brainstem and spinal cord, and has been proposed as an animal model of ALS. In symptomatic wobbler mice we found brain contents of glutamate, aspartate, and taurine similar to those in unaffected littermates, while brain contents of glutamine were increased, and those of serine and alanine were decreased. Spinal cords of wobbler mice had slightly decreased contents of glutamate, aspartate and glycine compared to normal littermates. Abnormalities of amino acid contents in the nervous system of wobbler mice are dissimilar to those in ALS patients suggesting a different pathogenesis of motoneuron loss.

Amyotrophic lateral sclerosis: fasting plasma levels of cysteine and inorganic sulfate are normal, as are brain contents of cysteine.

Recent reports suggest that amyotrophic lateral sclerosis (ALS) is caused by one or more unidentified neurotoxins that are poorly metabolized in patients to less toxic and more readily excreted compounds, and that a genetically determined defect in cysteine degradation and in inorganic sulfate production is the mechanism underlying a failure to metabolize xenobiotics normally in ALS. We measured concentrations of total cysteine and of inorganic sulfate in the plasma of age-matched groups of ALS patients and healthy control subjects and found no differences. L-Cysteine, a putative endogenous neurotoxin in ALS, was present in equal concentrations in autopsied brain from ALS patients and controls.

Puppet-like syndrome of Angelman: a pathologic and neurochemical study.

We present the first pathologic descriptions of the puppet-like syndrome of Angelman based on autopsy studies of a 21-year-old woman. The noteworthy findings were a small brain with mild cerebral atrophy but normal gyral development. There was marked cerebellar atrophy with loss of Purkinje and granule cells and extensive Bergmann's gliosis. Study of dendrite morphology using Golgi impregnations of the visual cortex revealed a prominent decrease in dendritic arborization of layer 3 and layer 5 pyramidal neurons. Quantitative Golgi analysis also revealed a significant decrease in the numbers of dendritic spines in apical layer 3 dendrites and both apical and basal layer 5 dendrites. Neurochemical studies of frozen brain tissue demonstrated markedly reduced gamma-aminobutyric acid content in the cerebellar cortex, as well as elevated glutamate content in the frontal and occipital cortices. Although there are no definite morphologic correlates of many of the clinical signs, the pronounced dendritic pathology and neurochemical abnormalities in cerebral cortex may provide a physiologic basis for mental retardation.