Exploring dietary changes in an interdisciplinary intervention trial: Application of a dietary guidelines food composition database

BACKGROUND

Consumption of food groups aligning with dietary guidelines is advised for obesity management and was used in a recent lifestyle intervention trial, the Health Track study. We have conducted a number of dietary pattern analyses on this trial but, with recent access to the new Australian Dietary Guidelines (ADG) food composition database, we can now assess ADG adherence, with the advantage of categorising mixed dishes. The present study aimed to compare changes over time in consumption of ADG food groups.

METHODS

Secondary analysis of baseline and three-month diet history data was conducted. Participants received individualised dietary advice (I), individualised dietary advice plus 30 g of walnuts per day (IW) or usual care (C). The ADG database was used to determine food group servings with changes in five food groups used as a measure of dietary quality.

RESULTS

Fruit and vegetable intakes increased in the IW (+0.4 and +1.1 serves, P < 0.05) and I (+0.5 and +0.4 serves, P > 0.05) arms. Consumption of meat/protein foods increased in the IW arm (+0.3 serves, P > 0.05) but decreased in the I and C arms (both - 0.4 serves, P < 0.05). Consumption of grains and milk/alternatives decreased in all study arms (P < 0.05). Greater improvements in grain and dairy food quality were observed in the intervention arms.

CONCLUSIONS

The ADG database enabled ADG specific food group analysis, addressed food quality and showed the HealthTrack intervention increased adherence to dietary guidelines compared to usual care.

Protein synthesis-dependent and -independent regulation of hippocampal synapses by brain-derived neurotrophic factor

A fundamental difference between short-term and long-term forms of synaptic plasticity is the dependence on transcription and translation of new genes. Using organotypic cultures of hippocampal slices, we have investigated whether the modulation of synapses by brain-derived neurotrophic factor (BDNF) also requires protein synthesis. Long-term treatment of hippocampal slice cultures with BDNF increased the number of docked vesicles, but not that of reserve pool vesicles, at CA1 excitatory synapses. BDNF also increased the levels of the vesicle proteins synaptophysin, synaptobrevin, and synaptotagmin, without affecting the presynaptic membrane proteins syntaxin and SNAP-25, or the vesicle-binding protein synapsin-I. The increase in synaptophysin and synaptobrevin expression was moderate (2-fold) and occurred within 6 h after BDNF application. In contrast, synaptotagmin expression took 24 h to reach maximum levels (5-fold). The delayed increase in synaptotagmin was blocked by protein synthesis inhibitors, while the early increase in synaptophysin and synaptobrevin was not. Moreover, the BDNF-induced increase of synaptotagmin was blocked by inhibiting the cAMP/protein kinase A (PKA) pathway. However, BDNF did not activate PKA, and application of a PKA activator did not mimic the BDNF effect. Taken together, these results suggest a novel, protein synthesis-dependent form of BDNF modulation that requires cAMP gating.

Activity-dependent neurotrophic factor: structure-activity relationships of femtomolar-acting peptides

Activity-dependent neurotrophic factor (ADNF) is a glia-derived protein that is neuroprotective at femtomolar concentrations. A 14-amino acid peptide of ADNF (ADNF-14) has been reported that protects cultured neurons from multiple neurotoxins. Structure-activity relationships of peptides related to ADNF-14 now have been determined. A 9-amino acid core peptide (ADNF-9) has been identified that has greater potency and a broader effective concentration range (10(-16) to 10(-13) M) than ADNF or ADNF-14 in preventing cell death associated with tetrodotoxin treatment of cerebral cortical cultures. Deletions or conservative amino acid substitutions to ADNF-9 resulted in reduced potency, narrower effective concentration range and/or decreased efficacy. Removal of the N-terminal serine or the COOH-terminal isoleucine-proline-alanine from ADNF-9 produced a significant reduction in survival-promoting activity. Comparative studies of ADNF-9 action in mixed (glia plus neurons) vs. glia-depleted neuronal cultures indicated that ADNF-9 can act directly on neurons, although the potency of the peptide was 10,000-fold greater in mixed cultures. Kinetic studies showed that exposure to ADNF-9 for only 2 hr was sufficient to produce a 4-day protection against the cell-killing action of tetrodotoxin. Treatment with bafilomycin A1 (an inhibitor of receptor-mediated endocytosis) for 2 hr prevented the ADNF- and ADNF-9-mediated neuroprotection. ADNF-9, like ADNF-14, was neuroprotective against N-methyl-D-aspartate and the beta-amyloid peptide (amino acids 25-35), and had a much broader range of effective concentrations than ADNF-14. These studies identify ADNF-9 as an attractive lead compound for the development of therapeutic agents against neurodegenerative diseases.

A randomized, double blind, controlled trial of tocolysis to assist external cephalic version in late pregnancy

BACKGROUND

External cephalic version at term is not always successful. This trial was done to ascertain whether tocolysis has any effect on the success rate.

METHODS

A randomized, double blind, controlled trial, with continuous paired sequential analysis. Fifty-one consecutive patients with a singleton fetus in a breech presentation between 36 and 38 weeks gestation, external version being attempted on each. Ritodrine infusion or placebo was infused before attempt at external cephalic version.

SETTING

A university teaching hospital with 8000 confinements annually.

RESULTS

Version was successful in 17 of the 25 patients given tocolysis, but in only eight of the 25 given placebo (p < 0.01). A positive benefit for tocolysis was shown after version had been completed in 10 pairs of patients. However the trial was continued until 25 pairs had been analyzed. The benefit deteriorated during analysis of the last 15 pairs suggesting that the initial benefit may reflect a learning curve for the procedure.

CONCLUSION

Tocolysis is likely to improve the success rate of external cephalic version in late pregnancy, especially in nulliparous mothers or where doctors are learning the technique.

Familial congenital diaphragmatic hernia: prenatal diagnosis, management, and outcome

Congenital diaphragmatic hernia (CDH) is a developmental defect of as yet unknown aetiology which accounts for 8 per cent of all major congenital anomalies and is associated with up to 80 per cent mortality despite optimal postnatal treatment. The risk of recurrence of CDH for future sibs after one affected infant is about 2 per cent. A multifactorial/threshold inheritance pattern with an observed high male:female sex ratio is currently favoured for the rare occurrence of familial CDH, although other modes of inheritance have also been described. We report three cases of familial CDH, two of whom were brother and sister sibs and the third was a first cousin, born within 18 months of each other. The diagnosis was by ultrasound and there were several factors predicting a poor outcome. The mortality in this group was 100 per cent. The prenatal diagnosis, treatment options, the unusual genetic aspects, outcome, and the pathology involved are discussed.

Serum lipid-associated sialic acid levels in gynecologic malignancies

Significantly elevated serum concentrations of lipid-associated sialic acid (LSA) were observed in 183 patients with invasive cervical carcinoma, 31 with uterine corpus adenocarcinoma and 71 with epithelial ovarian carcinoma prior to any treatment when compared with 50 normal control women (P < 0.05). Elevated LSA levels were also observed in five women with microinvasive cervical carcinoma and in four patients with uterine corpus leiomyosarcoma (P < 0.05). By contrast there were no significant elevations of serum LSA levels in 12 cases of cervical intraepithelial neoplasia, 32 of uterine corpus leiomyoma, 52 of benign ovarian cyst and 14 of mature ovarian teratoma when compared with normal control women. If the upper limit of the normal serum LSA concentration is set at 20 mg 100 ml-1, uterine corpus malignancy was distinguished from benign uterine corpus tumor with a sensitivity of 71% and a specificity of 94%; and ovarian malignancies were distinguished from benign ovarian masses with a sensitivity of 82% and a specificity of 85%. The positive predictive values of LSA assays in uterine and ovarian masses were 93% and 85%, respectively, whilst the negative predictive values were 75% and 81%, respectively. The sensitivity of LSA assays in cervical carcinoma was 57%. The present study suggests that serum LSA assays may be useful for the detection of gyncological malignancies.

Salivary oestradiol and progesterone after in vitro fertilization and embryo transfer using different luteal support regimens

Salivary oestradiol (E2) and progesterone (P) levels have been shown to reflect the biologically active fractions in the serum. The luteal-phase status of stimulated cycles was investigated after in vitro fertilization and embryo transfer (IVF-ET). Thirty patients were randomly allocated to one of three luteal therapy groups: group A had no support, group B had intramuscular P and group C had intramuscular P and human chorionic gonadotrophin (hCG). One pregnancy was achieved in group A, two in group B and three in group C. Significant correlations between salivary and serum levels of E2 and of P in matched samples during luteal phase were found. Salivary E2 levels from luteal day 8 through day 14 and P levels from day 3 through day 14 were significantly higher in the pregnant than in the nonpregnant cycles. Among the nonpregnant cycles, salivary E2 and P levels were significantly higher in group C than in group A or B. These findings suggest that, in stimulated cycles for IVF-ET, determination of salivary E2 and P levels may be used as reliable alternatives to serum concentrations for assessing the luteal phase. Also, the additional hCG has an enhanced luteotrophic effect, as reflected by the higher salivary E2 and P levels, which may lead to a better pregnancy rate.

Prevention of mite infestation of bedding by means of an impregnated sheet. A randomized controlled trial

A randomized controlled trial was conducted to test the effect of a sheet impregnated with benzyl benzoate in preventing mite infestation of new bedding. Impregnated sheets were placed on the mattresses of 17 subjects, while 19 subjects received placebo sheets. Over the following 2 years infestation occurred more commonly, and tended to be heavier, in the beds with inactive sheets than in those with impregnated sheets; among the 27 beds with three items of new bedding sampled on four occasions, a mite count of five or more occurred significantly more often where the sheet was inactive than where it was active (11 of 13 and 5 of 14 respectively). The application of a sheet impregnated with benzyl benzoate appears to prevent mite infestation and may be useful for patients with mite allergy who obtain new bedding as part of a mite-avoidance regimen.

Effects of anti-mite measures on children with mite-sensitive asthma: a controlled trial

Mite counts and tests for mite antigen were performed on samples of dust taken from the bedding of 53 children with mite-sensitive asthma. The samples from damp houses and the beds or enuretic children had markedly more mites and mite-antigen than those from dry houses. although the predominant species was usually Dermatophagoides pteronyssinus, some of the beds in the damp houses were heavily infested with another pyroglyphid mite Euroglyphus maynei, so that this was the species found in the greatest numbers. D pteronyssinus antigen was found to be correlated broadly with the total mite count, but more antigen was present for a given number of mites in the mattresses than in the blankets. The children were randomly allocated into two groups, one of which carried out rigorous anti-mite measures. The amounts of dust and mite antigen were reduced, though not the numbers of mites. Peak flow readings were monitored in the two groups for eight weeks and a final assessment made by a paediatrician who was unaware of the allocation of each patient in the trial. No significant differences emerged in the progress of the two groups, both tending to improve. Measures designed to remove mites from bedding do not greatly benefit the majority of children with mite-sensitive asthma.

Effect of a change to mite-free bedding on children with mite-sensitive asthma: a controlled trial

Twenty-one children with mite-sensitive asthma took part in a crossover randomised controlled trial of mite-free bedding. Each child was issued with a new sleeping bag and pillow for a month, and twice-daily peak flow readings were compared with those obtained during a month in the child's ordinary bedding. Seventeen of the children had higher mean peak flow readings during the period in the mite-free bedding (p < 0.01). The overall improvement was only modest, however, and some mites had appeared in most of the bedding by the end of the trial. New bedding may be helpful to patients with mite-sensitive asthma, but methods are needed to prevent colonisation by mites.

Mouse spinal cord in cell culture. I. Morphology and intrinsic neuronal electrophysiologic properties

1. Reliable methods for establishing fetal mouse spinal cord (SC) and dorsal root ganglion (DRG) cells in long term (greater than 1 mo) dissociated cell cultures are described. These cells have been studied by morphologic and intracellular electrophysiologic techniques. 2. Cells studied electrophysiologically can be relocated after preparation for electron microscopy and examined in thin sections. The electron microscope shows that the surface membranes of these cells were directly accessible to the culture medium. The surfaces of SC cells were studded with synaptic boutons, whereas the DRG cell surfaces generally had none. 3. Current-voltage relationships and linear electrotonic properties of the neurons are described. Delayed and anomalous rectification were seen in both cell types. The length of SC cell dendrites was about one characteristic electrotonic length, while little or no contribution of the relatively sparse DRG cell processes was seen in the transient responses of the DRG cells. 4. Postspike and posttetanic hyperpolarizations in DRG cells were due to a surface membrane conductance increase; this was probably primarily an increase in K+ conductance. Post-activation hyperpolarization in SC cells was primarily due to activation of an electrogenic Na+ pump.

Anti-mite measurements in mite-sensitive adult asthma. A controlled trial

A cross-over controlled trial has been conducted among 32 adult patients with mite-sensitive asthma. The bedclothes and pillows of each subject were laundered and vacuum-cleaned and a plastic cover applied to the mattress for six weeks in an attempt to reduce exposure to mites. No improvement in daily peak-flow reading or drug usage was found in comparison with a control period.