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The use of diagenetic alterations in bone microstructure ('histotaphonomy') as indicators of funerary treatment in the past and for post-mortem interval calculations in forensic cases has received increasing attention in the last decade. Studies have used histological changes to conclude in-situ decomposition, mummification, infanticide and post-mortem interval. There has been very little attempt to experimentally validate the links between decomposition, depositional conditions, time-since-death and microscopic changes in human bone so that meaningful interpretations of archaeological and forensic observations can be made. Here, we address this problem experimentally using the largest sample of human remains from anatomical donors and the longest-term deposition framework to date. This study tests one key assumption of histotaphonomy; that putrefaction during the early stages of decay is reflected in bone microanatomy and composition. Seventeen human donors and six pigs were deposited on the surface in a known Australian environment and left to decompose between 463 and 1238 days. All remains underwent all stages of decomposition reaching skeletonisation. Rib and femur samples were analysed using conventional histological methods and scanning electron microscopy, by applying the Oxford Histological Index, and examining collagen birefringence, microcracking and re- and de mineralisation. Biomolecular changes of the femoral samples were analysed using Fourier-transform infrared (FTIR) spectroscopy. The results indicate that bioerosion in human bone does not occur due to putrefaction. There were no correlations between bone histology and the following variables: human vs pigs, season, primary vs secondary deposition, position, fresh vs frozen and time-since-deposition. Furthermore, no trends were observed between biomolecular changes and time-since-deposition. The study also shows that pigs cannot be used as substitutes for human remains for bone biodegradation research. This is the first, controlled, larger scale study of human remains providing a lack of support for a long-assumed relationship between putrefaction and bone histology bioerosion. Using bone degradation as an argument to prove putrefaction, in-situ decomposition and early taphonomic processes cannot be supported based on the experimental human data presented. [ABSTRACT FROM AUTHOR]

Background: Historical data on smoking can enhance our comprehension of the effectiveness of past tobacco control policies and play a key role in developing targeted public health interventions. This study was undertaken to assess trends in smoking initiation and cessation in Australia for the period 1910–2005. Methods: Rates of smoking initiation and cessation were calculated for participants in two population-based cohorts, the Busselton Health Study and the Tasmanian Longitudinal Health Study. The effects of time trends, gender and age group were evaluated. Results: Of the 29,971 participants, 56.8% ever smoked. In males, over the period 1910–1999, the rate of smoking initiation in young adolescents remained high with a peak in the 1970s; in older adolescents it peaked in the 1940s and then declined; in young adults it showed a steady decline. In females, the rate of smoking initiation in young adolescents rose sharply in the 1960s and peaked in the 1970s, in older adolescents it increased throughout the period, and in young adults it declined after 1970. In the period 1930–2005, 27.3% of 9,605 people aged 36–50 years who smoked ceased smoking. Rates of cessation in this age group increased throughout but decreased in males after 1990 and plateaued around 2000 in females. Conclusion: Our findings show substantial variation in the efficacy of tobacco control policies across age groups, with a notable lack of success among the younger population. [ABSTRACT FROM AUTHOR]

Rationale: The term "pre–chronic obstructive pulmonary disease" ("pre-COPD") refers to individuals at high risk of developing COPD who do not meet conventional spirometric criteria for airflow obstruction. New approaches to identifying these individuals are needed, particularly in younger populations. Objectives: To determine whether lung function thresholds and respiratory symptoms can be used to identify individuals at risk of developing COPD. Methods: The Tasmanian Longitudinal Health Study comprises a population-based cohort first studied in 1968 (at age 7 yr). Respiratory symptoms, pre- and post-bronchodilator (BD) spirometry, diffusing capacity, and static lung volumes were measured in a subgroup at age 45, and the incidence of COPD was assessed at age 53. For each lung function measure, z-scores were calculated using Global Lung Function Initiative references. The optimal threshold for best discrimination of COPD incidence was determined by the unweighted Youden index. Measurements and Main Results: Among 801 participants who did not have COPD at age 45, the optimal threshold for COPD incidence by age 53 was pre-BD FEV1/FVC z-score less than −1.264, corresponding to the lowest 10th percentile. Those below this threshold had a 36-fold increased risk of developing COPD over an 8-year follow-up period (risk ratio, 35.8; 95% confidence interval, 8.88 to 144), corresponding to a risk difference of 16.4% (95% confidence interval, 3.7 to 67.4). The sensitivity was 88%, and the specificity was 87%. Positive and negative likelihood ratios were 6.79 and 0.14, respectively. Respiratory symptoms, post-BD spirometry, diffusing capacity, and static lung volumes did not improve on the classification achieved by pre-BD FEV1/FVC alone. Conclusions: This is the first study, to our knowledge, to evaluate the discriminatory accuracy of spirometry, diffusing capacity, and static lung volume thresholds for COPD incidence in middle-aged adults. Our findings support the inclusion of pre-BD spirometry in the physiological definition of pre-COPD and indicate that pre-BD FEV1/FVC at the 10th percentile accurately identifies individuals at high risk of developing COPD in community-based settings. [ABSTRACT FROM AUTHOR]

Malaria and lymphatic filariasis transmitted by female Anopheles mosquitoes remain health challenges in tropical Africa. Resistance by vectors to synthetic insecticides limits control efforts. This study evaluated efficacy of essential oils of Eryngium foetidum and Plectranthus amboinicus against Anopheles gambiae. Test oils were obtained by hydrodistillation using Clevenger apparatus. From 1 mL stock solution, 31.25, 62.50, 125 and 250 and 500 µL/mL concentrations of E. foetidum and P. amboinicus oils were prepared using serial-dilution with tween 80 as diluent. Each concentration had eighty adult mosquitoes exposed. Results of knockdown and insecticidal tests after 30 and 60 minutes respectively revealed higher susceptibility of An. gambiae to E. foetidum. Eryngium foetidum (250µL/mL) elicited 100% knockdown after 20 minutes. In the insecticidal test, the same concentration resulted in 100% mortality at 40 minutes. Same effect was observed for 500 µL/mL of P. amboinicus oil at 25 and 60 minutes. From Probit analysis, KD50 values were 66.793 and 251.350 µL/mL for E. foetidum and P. amboinicus respectively. Values for LC50 were 85.818 and 428.663 µL/mL for E. foetidum and P. amboinicus respectively. Results demonstrate that E. foetidum oil holds promise as control agent against An. gambiae. Plectranthus amboinicus oil did not demonstrate appreciable efficacy. [ABSTRACT FROM AUTHOR]

Background: The extent to which biomarkers of asthma activity persist in spontaneous asthma remission and whether such markers are associated with future respiratory outcomes remained unclear. We investigated the association between sub‐clinical inflammation in adults with spontaneous asthma remission and future asthma relapse and lung function decline. Methods: The Tasmanian Longitudinal Health Study is a population‐based cohort (n = 8583). Biomarkers of systemic inflammation were measured on participants at age 45, and latent profile analysis was used to identify cytokine profiles. Bronchial hyperresponsiveness (BHR) and nitric oxide products in exhaled breath condensate (EBC NOx) were measured at age 50. Participants with spontaneous asthma remission at ages 45 (n = 466) and 50 (n = 318) were re‐evaluated at age 53, and associations between baseline inflammatory biomarkers and subsequent asthma relapse and lung function decline were assessed. Results: We identified three cytokine profiles in adults with spontaneous asthma remission: average (34%), Th2‐high (42%) and Th2‐low (24%). Compared to the average profile, a Th2‐high profile was associated with accelerated decline in post‐BD FEV1/FVC (MD −0.18% predicted per‐year; 95% CI −0.33, −0.02), while a Th2‐low profile was associated with accelerated decline in both post‐BD FEV1 (−0.41%; −0.75, −0.06) and post‐BD FVC (−0.31%; −0.62, 0.01). BHR and high TNF‐α during spontaneous remission were associated with an increased risk of asthma relapse. In contrast, we found no evidence of association between EBC NOx and either asthma relapse or lung function decline. Conclusion: BHR and serum inflammatory cytokines have prognostic value in adults with spontaneous asthma remission. At‐risk individuals with BHR, Th2‐high or Th2‐low cytokine profiles may benefit from closer monitoring and on‐going follow‐up. [ABSTRACT FROM AUTHOR]

Background and Objective: The association between birth weight, particularly relative to gestational age, and adult lung function is uncertain. We investigated the associations between birth weight relative to gestational age and measures of lung function in middle age, and mediation of these associations by adult height. Methods: Participants in the Tasmanian Longitudinal Health Study who had both known birth weight and lung function assessment at age 45 years were included (n = 849). Linear regression models were fitted to investigate the association between small for gestational age and birth weight with post‐bronchodilator lung function measures (forced expiratory volume in 1 second [FEV1], forced vital capacity [FVC], FEV1/FVC, diffusing capacity for carbon monoxide [DLco], residual volume [RV] and total lung capacity [TLC]), adjusting for potential confounders. The contribution of adult height as a mediator of these associations was investigated. Results: Compared with infants born with normal weight for gestational age, those born small for gestational age had reduced FEV1 (coefficient: −191 ml [95%CI: −296, −87]), FVC (−205 ml [−330, −81]), TLC (−292 ml [−492, −92]), RV (−126 ml [−253, 0]) and DLco (−0.42 mmol/min/kPa [−0.79, −0.041]) at age 45 years. However, they had comparable FEV1/FVC. For every 1 kg increase in birth weight, lung function indices increased by an average of 117 ml (95%CI: 40, 196) for FEV1, 124 ml (30, 218) for FVC, 215 ml (66, 365) for TLC and 0.36 mmol/min/kPa (0.11, 0.62) for DLco, independent of gestational age, but again not for FEV1/FVC. These associations were significantly mediated by adult height (56%–90%). Conclusion: Small for gestational age was associated with reduced lung function that is likely due to smaller lungs with little evidence of any specific parenchymal impairment. [ABSTRACT FROM AUTHOR]