Frequent use of paracetamol and risk of allergic disease among women in an Ethiopian population

Introduction

The hypothesis that paracetamol might increase the risk of asthma and other allergic diseases have gained support from a range of independent studies. However, in studies based in developed countries, the possibility that paracetamol and asthma are associated through aspirin avoidance is difficult to exclude.

Objectives

To explore this hypothesis among women in a developing country, where we have previously reported aspirin avoidance to be rare.

Methods

In 2005/6 a population based cohort of 1065 pregnant women was established in Butajira, Ethiopia and baseline demographic data collected. At 3 years post birth, an interview-based questionnaire administered to 945 (94%) of these women collected data on asthma, eczema, and hay fever in the past 12 month, frequency of paracetamol use and potential confounders. Allergen skin tests to Dermatophagoides pteronyssinus and cockroach were also performed. The independent effects of paracetamol use on allergic outcomes were determined using multiple logistic regression analysis.

Findings

The prevalence of asthma, eczema and hay fever was 1.7%, 0.9% and 3.8% respectively; of any one of these conditions 5.5%, and of allergen sensitization 7.8%. Paracetamol use in the past month was reported by 29%, and associations of borderline significance were seen for eczema (adjusted OR (95% CI) = 8.51 (1.68 to 43.19) for 1–3 tablets and 2.19 (0.36 to 13.38) for ≥4 tablets, compared to no tablets in the past month; overall p = 0.055) and for ‘any allergic condition’ (adjusted OR (95% CI) = 2.73 (1.22 to 6.11) for 1–3 tablets and 1.35 (0.67 to 2.70) for ≥4 tablets compared to 0 in the past month; overall p = 0.071).

Conclusions

This study provides further cross-sectional evidence that paracetamol use increases the risk of allergic disease.     

RedeR: R/Bioconductor package for representing modular structures, nested networks and multiple levels of hierarchical associations

Visualization and analysis of molecular networks are both central to systems biology. However, there still exists a large technological gap between them, especially when assessing multiple network levels or hierarchies. Here we present RedeR, an R/Bioconductor package combined with a Java core engine for representing modular networks. The functionality of RedeR is demonstrated in two different scenarios: hierarchical and modular organization in gene co-expression networks and nested structures in time-course gene expression subnetworks. Our results demonstrate RedeR as a new framework to deal with the multiple network levels that are inherent to complex biological systems. RedeR is available from http://bioconductor.org/packages/release/bioc/html/RedeR.html.     

Different susceptibility of rat pancreatic alpha and beta cells to hypoxia

Insulin-producing beta cells are known to be highly susceptible to hypoxia, which is a major factor in their destruction after pancreatic islet transplantation. However, whether the glucagon-producing pancreatic islet alpha cells are sensitive to hypoxia is not known. Our objective was to compare the sensitivity of alpha and beta cells to hypoxia. Isolated rat pancreatic islets were exposed to hypoxia (1% oxygen, 94% N(2), 5% CO(2)) for 3 days. The viability of the alpha and beta cells, as well as the stimulus-specific secretion of glucagon and insulin, was evaluated. A quantitative analysis of the proportion of beta to alpha cells indicated that, under normoxic conditions, islet cells were composed mainly of beta cells (87 ± 3%) with only 13 ± 3% alpha cells. Instead, hypoxia treatment significantly increased the proportion of alpha cells (40 ± 13%) and decreased the proportion of beta cells to 60 ± 13%. Using the fluorescent TUNEL assay we found that only a few percent of beta cells and alpha cells were apoptotic in normoxia. In contrast, hypoxia induced an abundance of apoptotic beta cells (61 ± 22%) and had no effect on the level of apoptosis in alpha cells. In conclusion, this study demonstrates that hypoxia results in severe functional abnormality in both beta and alpha cells while alpha cells display significantly decreased rate of apoptosis compared to intensive apoptotic injury of beta cells. These findings have implications for the understanding of the possible role of hypoxia in the pathophysiology of diabetes.     

Short-term variation in species richness across an altitudinal gradient of alpine summits

In response to climate warming, high altitude alpine vegetation may be replaced by typically lower altitude species, as species re-assemble and migrate to new areas. However, empirical evidence showing vegetation change in response to climate warming is largely unavailable for Australian alpine areas. Here, we examine changes in species richness with respect to climate and altitude over a 7?year period at a range of spatial scales in a re-survey of five alpine summits that are part of the Global Observation Research Initiative in Alpine Environments monitoring network. Eighty species were recorded in 2011 across all summits, an increase of 6 species since 2004. Mean species richness increased at the whole-of-summit scale from 45 to 50 species (about 12?%). At this scale, the rate of species richness increase was almost one new species per year, with 15 new species recorded at one summit. Here, shrub and graminoid species showed the largest increases. At the smaller spatial scales, changes in species richness were less pronounced. Turnover at the species and community level was typically moderate at all spatial scales and on all summits. The strength and direction of species richness change (the difference in species richness between the two sample periods, +/?) was not related to altitude nor variation in climate. Future re-surveys of the summits will confirm whether these short-term variations in species richness, particularly increases in shrubs, are indeed signals of longer-term trends and interactions with a changing climate.     

Nitrogen in global animal production and management options for improving nitrogen use efficiency

Animal production systems convert plant protein into animal protein. Depending on animal species, ration and management, between 5% and 45 % of the nitrogen (N) in plant protein is converted to and deposited in animal protein. The other 55%-95% is excreted via urine and feces, and can be used as nutrient source for plant (= often animal feed) production. The estimated global amount of N voided by animals ranges between 80 and 130 Tg N per year, and is as large as or larger than the global annual N fertilizer consumption. Cattle (60%), sheep (12%) and pigs (6%) have the largest share in animal manure N production. The conversion of plant N into animal N is on average more efficient in poultry and pork production than in dairy production, which is higher than in beef and sheep production. However, differences within a type of animal production system can be as large as differences between types of animal production systems, due to large effects of the genetic potential of animals, animal feed and management. The management of animals and animal feed, together with the genetic potential of the animals, are key factors to a high efficiency of conversion of plant protein into animal protein. The efficiency of the conversion of N from animal manure, following application to land, into plant protein ranges between 0 and 60%, while the estimated global mean is about 15%. The other 40%-100% is lost to the wider environment via NH3 volatilization, denitrification, leaching and run-off in pastures or during storage and/or following application of the animal manure to land. On a global scale, only 40%-50% of the amount of N voided is collected in barns, stables and paddocks, and only half of this amount is recycled to crop land. The N losses from animal manure collected in barns, stables and paddocks depend on the animal manure management system. Relative large losses occur in confined animal feeding operations, as these often lack the land base to utilize the N from animal manure effectively. Losses will be relatively low when all manure are collected rapidly in water-tight and covered basins, and when they are subsequently applied to the land in proper amounts and at the proper time, and using the proper method (low-emission techniques). There is opportunity for improving the N conversion in animal production systems by improving the genetic production potential of the herd, the composition of the animal feed, and the management of the animal manure. Coupling of crop and animal production systems, at least at a regional scale, is one way to high N use efficiency in the whole system. Clustering of confined animal production systems with other intensive agricultural production systems on the basis of concepts from industrial ecology with manure processing is another possible way to improve N use efficiency.     

Improving clinical prediction rules in acute kidney injury with the use of biomarkers of cell cycle arrest: a pilot study

Introduction: Early recognition of patients developing acute kidney injury (AKI) is of considerable interest, we report the first use of a combination of a clinical prediction rule with a biomarker in emergent adult medical patients to improve AKI recognition.

Methods: Single-centre prospective pilot study of medical admissions without AKI identified as high risk by a clinical prediction rule. Urine samples were obtained and tissue inhibitor of metalloproteinases-2 (TIMP-2) and insulin-like growth factor binding protein 7 (IGFBP7) – biomarkers associated with cell cycle arrest, were measured.

Outcome: Creatinine-based KDIGO hospital-acquired AKI (HA-AKI).

Results: Of 69 patients recruited, HA-AKI developed in 13% (n?=?9), in whom biomarker values were higher (median 0.43 (interquartile range (IQR) 0.21–1.25) vs. 0.07 (0.03–0.16) in cases without (p?=?0.008). Peak rise in creatinine was higher in biomarker positive cases (median 30?μmol/L (7–72) vs. 1?μmol/L (0–16), p?=?0.002). AUROC was 0.78 (95% CI 0.57–0.98). At the suggested cut-off (0.3) sensitivity for predicting AKI was 78% (95% CI 40–97%), specificity 89% (78–95%), positive predictive value 50% (31–69%) and negative predictive value 96% (89–99%).

Discussion: Addition of a urinary biomarker allows exclusion of a significant number of patients identified to be at higher risk of AKI by a clinical prediction rule.     

Identification of structural DNA variations in human cell cultures after long-term passage

Random amplified polymorphic DNA (RAPD) analysis was adapted for genomic identification of cell cultures and evaluation of DNA stability in cells of different origin at different culture passages. DNA stability was observed in cultures after no more than 5 passages. Adipose-derived stromal cells demonstrated increased DNA instability. RAPD fragments from different cell lines after different number of passages were cloned and sequenced. The chromosomal localization of these fragments was identified and single-nucleotide variations in RAPD fragments isolated from cell lines after 8–12 passages were revealed. Some of them had permanent localization, while most variations demonstrated random distribution and can be considered as de novo mutations.     

96-Well solid-phase extraction: a brief history of its development

This communication describes the invention and further development of the first 96-well solid-phase extraction system and the original purposes to which it was put. We also describe the adaption of this system for bioanalysis of pharmaceutically active small molecules and the needs underlying it. The system has become a world-wide standard for high-throughput bioanalysis and has been extended by others to include, for example, disk-phase extraction and supported liquid-liquid extraction, as well as 384-well systems. The factors that enabled this leap forward in productivity are discussed.     

Population parameters and exploitation rate of Sarotherodon galilaeus galilaeus (Cichlidae) in Lakes Doukon and Togbadji,Benin

Growth, mortality, recruitment and relative yield per recruit of Sarotherodon galilaeus galilaeus from Lakes Doukon and Togbadji were studied. Data on total length, total weight and sex were recorded on a monthly basis between January and December 2013 for S. g. galilaeus captured by local fishers. The estimated asymptotic lengths L_∞ were 26.2 and 23.6?cm for Lakes Doukon and Togbadji, respectively, while the growth rate K was 0.73 in Lake Doukon and 0.87 in Lake Togbadji. Estimates of fishing mortality, 0.27 and 0.47 y^?1 for Doukon and Togbadji, respectively, were low relative to natural mortality, 1.51 and 1.74 y^?1, respectively. Sizes at first sexual maturity were 12.8 and 13.2?cm for females and males, respectively, in Lake Doukon, and 11.5 and 12.4?cm for females and males, respectively, in Lake Togbadji. The size at first capture was estimated at 13.3 and 12.7?cm for Lakes Doukon and Togbadji, respectively, which, in the light of the size at maturity estimates, indicates that fish spawn at least once before capture. The current exploitation rates of 0.15 for Lake Doukon and 0.21 for Lake Togbadji suggest that their stocks of S. g. galilaeus are not overexploited in either lake.