Family and infant characteristics associated with timing of core and non-core food introduction in early childhood

Objective

To identify family and infant characteristics associated with timing of introduction of two food types: core foods (nutrient-dense) and non-core foods (nutrient-poor) in a population-based sample of mothers and infants.

Method

Participants were 1861 mothers and infants from the Gemini twin birth cohort (one child per family). Family and infant characteristics were assessed when the infants were around 8 months old. Timing of introducing core and non-core foods was assessed at 8 and 15 months. As the distributions of timing were skewed, three similar-sized groups were created for each food type: earlier (core: 1–4 months; non-core: 3–8 months), average (core: 5 months; non-core: 9–10 months), and later introduction (core: 6–12 months; non-core: 11–18 months). Ordinal logistic regression was used to examine predictors of core and non-core food introduction, with bootstrapping to test for differences between the core and non-core models.

Results

Younger maternal age, lower education level, and higher maternal BMI were associated with earlier core and non-core food introduction. Not breastfeeding for at least 3 months and higher birth weight were specifically associated with earlier introduction of core foods. Having older children was specifically associated with earlier introduction of non-core foods.

Conclusion

There are similarities and differences in the characteristics associated with earlier introduction of core and non-core foods. Successful interventions may require a combination of approaches to target both food types.

Cardiovascular diseases in older patients with osteoporotic hip fracture: prevalence, disturbances in mineral and bone metabolism, and bidirectional links

BACKGROUND

Considerable controversy exists regarding the contribution of mineral/bone metabolism abnormalities to the association between cardiovascular diseases (CVDs) and osteoporotic fractures.

AIMS AND METHODS

To determine the relationships between mineral/bone metabolism biomarkers and CVD in 746 older patients with hip fracture, clinical data were recorded and serum concentrations of parathyroid hormone (PTH), 25-hydroxyvitamin D, calcium, phosphate, magnesium, troponin I, parameters of bone turnover, and renal, liver, and thyroid functions were measured.

RESULTS

CVDs were diagnosed in 472 (63.3%) patients. Vitamin D deficiency was similarly prevalent in patients with (78.0%) and without (82.1%) CVD. The CVD group had significantly higher mean PTH concentrations (7.6 vs 6.0 pmol/L, P < 0.001), a higher prevalence of secondary hyperparathyroidism (SPTH) (PTH > 6.8 pmol/L, 43.0% vs 23.3%, P < 0.001), and excess bone resorption (urinary deoxypyridinoline corrected by creatinine [DPD/Cr] > 7.5 nmol/μmol, 87.9% vs 74.8%, P < 0.001). In multivariate regression analysis, SHPT (odds ratio [OR] 2.6, P = 0.007) and high DPD/Cr (OR 2.8, P = 0.016) were independent indictors of CVD. Compared to those with both PTH and DPD/Cr in the normal range, multivariate-adjusted ORs for the presence of CVD were 17.3 (P = 0.004) in subjects with SHPT and 9.7 (P < 0.001) in patients with high DPD/Cr. CVD was an independent predicator of SHPT (OR 2.8, P = 0.007) and excess DPD/Cr (OR 2.5, P = 0.031). CVD was predictive of postoperative myocardial injury, while SHPT was also an independent predictor of prolonged hospital stay and in-hospital death.

CONCLUSION

SHPT and excess bone resorption are independent pathophysiological mediators underlying the bidirectional associations between CVD and hip fracture, and therefore are important diagnostic and therapeutic targets.

A prospective study of human papillomavirus (HPV) testing to resolve uncertainty in colposcopy

OBJECTIVE

UK colposcopy services are seeing increased workloads, a large proportion of which are follow-up appointments. The English Cervical Screening Programme HPV Special Interest Group identified five subcategories of colposcopy clinic patients who often require prolonged follow-up regimes for low-grade abnormalities. Human papillomavirus (HPV) testing has a high negative predictive value, meaning that HPV-negative women are at very low risk of underlying disease. Our objectives were to quantify the number of HPV-negative women in each study subcategory and to evaluate the number who could potentially be discharged from colposcopy on the basis of their results.

METHODS

Four colposcopy clinics prospectively identified women according to five categories over 12 months. All women underwent cytological testing and high-risk HPV (hrHPV) testing using the Hybrid Capture 2 test. Management outcomes and decisions based on a knowledge of the HPV status were recorded.

RESULTS

Data available on 755 women showed that 422/755 (55.9%) and 260/755 (34.4%) had persistent cervical intraepithelial neoplasia grade 1 (CIN1) (Category 1) or a minor abnormality following treatment (Category 2), respectively. In Categories 1 and 2, 51.7% and 60.2%, respectively, were hrHPV negative. The rates with biopsies of CIN2 or worse (CIN2+) across the two categories were 3/355 (0.8%) and 21/291 (7.0%) for hrHPV-negative and hrHPV-positive women, respectively.

CONCLUSION

The incorporation of hrHPV testing within organized cervical screening programmes has been widely accepted. hrHPV testing for the clinical scenarios outlined in this study detects women who are hrHPV negative and therefore at low risk of underlying disease, potentially reducing anxiety and inconvenience for women and costs to colposcopy services.

Tumour-free distance from serosa is a better prognostic indicator than depth of invasion and percentage myometrial invasion in endometrioid endometrial cancer

OBJECTIVE

To evaluate the prognostic performance of tumour-free distance (TFD) compared with depth of invasion (DOI) and percentage of myometrial invasion (MI).

DESIGN

Retrospective cohort study.

SETTING

Regional gynaecological oncology centre.

POPULATION

All women identified with stage I-III endometrioid endometrial carcinoma from January 2000 to December 2007, who had surgery at the Northern Gynaecological Oncology Centre (NGOC).

METHODS

Surgicopathological, follow-up and survival data were collected. Univariate and multivariate analyses were performed comparing TFD, DOI and MI with known prognostic factors. The prognostic accuracy of TFD was assessed by receiver operating characteristic (ROC) curve analyses, and an optimum cut-off was proposed.

MAIN OUTCOME MEASURES

Death from disease, recurrence and pelvic lymph node involvement.

RESULTS

A total of 288 women were identified. The median follow-up time was 67 months, with 40 recurrences and 32 disease-related deaths. When TFD, DOI and MI were separately examined in multivariate analyses with other covariates, TFD was an independent predictor of death from disease (HR 1.22; 95% CI 1.00-1.48; P = 0.05). In multivariate analyses including all three measures together (TFD, DOI and MI), TFD was an independent predictor of death from disease (HR 1.49; 95% CI 1.03-2.16; P = 0.04) and recurrence (HR 1.39; 95% CI 1.01-1.91; P = 0.05). TFD was also an independent predictor of lymph node involvement when examined separately (OR 0.74; 95% CI 0.56-0.96; P = 0.03), and together with DOI and MI (OR 0.67; 95% CI 0.49-0.92; P = 0.01), in women who had pelvic lymphadenectomy (n = 86). A TFD cut-off of 1.75 mm showed good prognostic performance.

CONCLUSIONS

The TFD measure may be a more accurate method of representing myometrial invasion in the staging for endometrial cancer.

Observation of magnetically induced transparency in a classical magnetized plasma

We report the first demonstration of magnetically induced transmission in an opaque magnetized plasma. Magnetically induced transmission in a plasma is a classical analog to the electromagnetically induced transparency in atomic systems. The transmission of radiation through an axially magnetized plasma is obtained by applying an additional one dimensional transverse spatial periodic magnetic field. The transverse-periodic magnetic field uncouples the right-hand electromagnetic wave from interacting with plasma electrons, rendering the plasma band-stop transparent. This provides means to control the extent of absorption of electromagnetic radiation in magnetized plasma.

Monitoring indicates greater resilience for birds than for mammals in Kakadu National Park, northern Australia

Context A previous study reported major declines for native mammal species from Kakadu National Park, over the period 2001–09. The extent to which this result may be symptomatic of more pervasive biodiversity decline was unknown. Aims Our primary aim was to describe trends in the abundance of birds in Kakadu over the period 2001–09. We assessed whether any change in bird abundance was related to the arrival of invading cane toads (Rhinella marina), and to fire regimes. Methods Birds were monitored at 136 1-ha plots in Kakadu, during the period 2001–04 and again in 2007–09. This program complemented sampling of the same plots over the same period for native mammals. Key results In contrast to the decline reported for native mammals, the richness and total abundance of birds increased over this period, and far more individual bird species increased than decreased. Fire history in the between-sampling period had little influence on trends for individual species. Interpretation of the overall positive trends for bird species in Kakadu over this period should be tempered by recognition that most of the threatened bird species present in Kakadu were unrecorded in this monitoring program, and the two threatened species for which there were sufficient records to assess trends – partridge pigeon (Geophaps smithii) and white-throated grass-wren (Amytornis woodwardi) – both declined significantly. Conclusions The current decline of the mammal fauna in this region is not reflected in trends for the region’s bird fauna. Some of the observed changes (mostly increases) in the abundance of bird species may be due to the arrival of cane toads, and some may be due to local or regional-scale climatic variation or variation in the amount of flowering. The present study provides no assurance about threatened bird species, given that most were inadequately recorded in the study (perhaps because their decline pre-dated the present study). Implications These contrasting trends between mammals and birds demonstrate the need for biodiversity monitoring programs to be broadly based. The declines of two threatened bird species over this period indicate the need for more management focus for these species.

Ion temperature and hydrodynamic-energy measurements in a Z-pinch plasma at stagnation

The time history of the local ion kinetic energy in a stagnating plasma was determined from Doppler-dominated line shapes. Using independent determination of the plasma properties for the same plasma region, the data allowed for inferring the time-dependent ion temperature, and for discriminating the temperature from the total ion kinetic energy. It is found that throughout most of the stagnation period the ion thermal energy constitutes a small fraction of the total ion kinetic energy; the latter is dominated by hydrodynamic motion. Both the ion hydrodynamic and thermal energies are observed to decrease to the electron thermal energy by the end of the stagnation period. It is confirmed that the total ion kinetic energy available at the stagnating plasma and the total radiation emitted are in balance, as obtained in our previous experiment. The dissipation time of the hydrodynamic energy thus appears to determine the duration (and power) of the K emission.

The mammal fauna of the Sir Edward Pellew island group, Northern Territory, Australia: refuge and death-trap

Context Australian islands have provided a major conservation refuge for many native mammals; however, conversely, island populations may also be highly susceptible to the introduction of novel threats. Nearby islands subject to different arrays of threats or different timing of arrival of those threats may provide a natural experiment, offering particular insight into the relative impacts of different threats to Australian mammals more generally. Aims The present study sought to document the native mammal fauna occurring on the main islands of the Sir Edward Pellew group, Northern Territory, and the changes in that fauna over a ~50-year period, and to seek to identify those factors that have contributed to such change. Methods In different combinations, the five main islands (and three smaller islands) were subject to standard wildlife survey methods in 1966–67, 1988, 2003, 2004–05, and 2009–10. Sampling procedures were not identical in all periods; however, a measure of abundance (trap success rate) could be calculated for all sampling. This conventional survey approach was complemented by documentation of ethno-biological knowledge. Key results For many species, these islands held populations of biogeographic or conservation significance. However, there has been a major loss or decline of mammal species from most islands. Extirpation is difficult to prove; however, we consider it most likely that the important regional populations of brush-tailed rabbit-rat (Conilurus penicillatus), northern quoll (Dasyurus hallucatus), northern brush-tailed phascogale (Phascogale pirata), common brushtail possum (Trichosurus vulpecula) and canefield rat (Rattus sordidus) have been lost from these islands, and that northern brown bandicoot (Isoodon macrourus), western chestnut mouse (Pseudomys nanus), pale field-rat (Rattus tunneyi) and long-haired rat (Rattus villosissimus) have been lost from most of the islands on which they formerly occurred. Some species–island combinations are known only from the ethno-biological record, and the loss of these populations probably mostly occurred in the period 30–50 years ago. Many other declines and losses occurred in the period between the second (1988) and third (2003) survey. The loss of the northern quoll from Vanderlin Island occurred in 2008. No single factor unambiguously accounts for the declines, although the introduction of cats (Felis catus) provides the best fit to the pattern of decline. A notable exception is the extirpation of northern quoll on Vanderlin Island, which is closely linked to the colonisation of that island by cane toads (Rhinella marina). Conclusions The Sir Edward Pellew group of islands have lost much of their formerly high conservation significance for native mammals over the past 50 years, mostly because of introductions of cats, and to a lesser extent, natural colonisation of the islands by cane toads. Implications The present study has provided some insight into the relative impacts of a range of factors that have been considered as possibly implicated in the decline of native mammals on the northern Australian mainland, with most support being offered here for a primary role for predation by feral cats. The study has also demonstrated the need for better quarantining of islands with significant conservation values. The comprehensive natural colonisation of these islands by cane toads offers a further lesson, of most importance to managers of islands in north-western Australia currently just beyond the range of toads.

Monitoring indicates rapid and severe decline of native small mammals in Kakadu National Park, northern Australia

Context. Australia has a lamentable history of mammal extinctions. Until recently, the mammal fauna of northern Australia was presumed to have been spared such loss, and to be relatively intact and stable. However, several recent studies have suggested that this mammal fauna may be undergoing some decline, so a targeted monitoring program was established in northern Australia’s largest and best-resourced conservation reserve. Aims. The present study aims to detect change in the native small-mammal fauna of Kakadu National Park, in the monsoonal tropics of northern Australia, over the period of 1996–2009, through an extensive monitoring program, and to consider factors that may have contributed to any observed change. Methods. The small-mammal fauna was sampled in a consistent manner across a set of plots established to represent the environmental variation and fire regimes of Kakadu. Fifteen plots were sampled three times, 121 plots sampled twice and 39 plots once. Resampling was typically at 5-yearly intervals. Analysis used regression (of abundance against date), and Wilcoxon matched-pairs tests to assess change. For resampled plots, change in abundance of mammals was related to fire frequency in the between-sampling period. Key results. A total of 25 small mammal species was recorded. Plot-level species richness and total abundance decreased significantly, by 54% and 71%, respectively, over the course of the study. The abundance of 10 species declined significantly, whereas no species increased in abundance significantly. The number of ‘empty’ plots increased from 13% in 1996 to 55% in 2009. For 136 plots sampled in 2001–04 and again in 2007–09, species richness declined by 65% and the total number of individuals declined by 75%. Across plots, the extent of decline increased with increasing frequency of fire. The most marked declines were for northern quoll, Dasyurus hallucatus, fawn antechinus, Antechinus bellus, northern brown bandicoot, Isoodon macrourus, common brushtail possum, Trichosurus vulpecula, and pale field-rat, Rattus tunneyi. Conclusions. The native mammal fauna of Kakadu National Park is in rapid and severe decline. The cause(s) of this decline are not entirely clear, and may vary among species. The most plausible causes are too frequent fire, predation by feral cats and invasion by cane toads (affecting particularly one native mammal species). Implications. The present study has demonstrated a major decline in a key conservation reserve, suggesting that the mammal fauna of northern Australia may now be undergoing a decline comparable to the losses previously occurring elsewhere in Australia. These results suggest that there is a major and urgent conservation imperative to more precisely identify, and more effectively manage, the threats to this mammal fauna.