Sublethal effects of industrial chemicals on fish fingerlings (Tilapia guineensis)

Tilapia guineensis commonly found in the Niger Delta ecological zone of Nigeria was exposed to sublethal concentrations (1.56, 3.13 mg/l) of neatex (industrial detergent) and norust CR 486 (corrosion inhibitor) using the Organisation for Economic Cooperation and Development (OECD) # 203 protocol. At test termination on the 28th day, the rate of bioaccumulation of surfactants in the fish gills, gut and muscle tissues were measured. The levels of surfactant in the gills, gut and muscle tissues were significantly different at levels of p < 0.05 in fish exposed to neatex and norust CR 486. Surfactant levels in the fish also increased significantly with increase in concentrations. Surfactant accumulation in the test treatments may be an indication that the observed effects on the exposed fish may have been due to the chemicals. This study demonstrates the sublethal effects of surfactant-containing industrial chemicals on T. guineensis, an economic and ecologically important sentinel

Toxicity of Neatex (industrial detergent) and Norust CR 486 (corrosion inhibitors) to earthworms (Aporrectodea longa) in naturally spiked soil

Ecological effects of indiscriminate disposal of industrial chemicals into soils of the Niger Delta environment of Nigeria were assessed using earthworms in spiked natural soil in the laboratory. Populations of indigenous epigeic adult earthworms, Aporrectodea longa, were exposed to varying concentrations of two chemicals (industrial detergent and corrosion inhibitor) in natural soil to determine the acute toxicity of the chemicals. Earthworm acute toxicity test (OECD) 207 method was employed. After two weeks of earthworm exposure to Neatex and Norust CR 486 concentrations of 62.5, 125, 250 and 500 mg/kg, percentage mortality was measured as the ecological endpoint in the earthworms. Based on OECD 2003 guidelines, the chemically spiked soil rating showed that bothchemicals were slightly toxic. The estimated LC50 concentrations showed that Norust CR 486 (corrosion inhibitor) was more toxic than Neatex (detergent) at p < 0.05, t = 8.213. Earthworm mean mortality in both chemicals increased with increasing concentrations and exposure duration. Mean mortality observed in Neatex and Norust CR 486 were significantly different from the negative control suggesting that mortality may be attributed to the effect of the chemicals. The results obtained aretherefore indications of early warning signs of future soil deteriorations occasioned by indiscriminate disposal of these chemicals in the Niger Delta environment. This calls for regular monitoring and sustainable effluent disposal management

Functional genomic analysis and neuroanatomical localization of miR-2954, a song-responsive sex-linked microRNA in the zebra finch

Natural experience can cause complex changes in gene expression in brain centers for cognition and perception, but the mechanisms that link perceptual experience and neurogenomic regulation are not understood. MicroRNAs (miRNAs or miRs) have the potential to regulate large gene expression networks, and a previous study showed that a natural perceptual stimulus (hearing the sound of birdsong in zebra finches) triggers rapid changes in expression of several miRs in the auditory forebrain. Here we evaluate the functional potential of one of these, miR-2954, which has been found so far only in birds and is encoded on the Z sex chromosome. Using fluorescence in situ hybridization and immunohistochemistry, we show that miR-2954 is present in subsets of cells in the sexually dimorphic brain regions involved in song production and perception, with notable enrichment in cell nuclei. We then probe its regulatory function by inhibiting its expression in a zebra finch cell line (G266) and measuring effects on endogenous gene expression using Illumina RNA sequencing (RNA-seq). Approximately 1000 different mRNAs change in expression by 1.5-fold or more (adjusted p < 0.01), with increases in some but not all of the targets that had been predicted by Targetscan. The population of RNAs that increase after miR-2954 inhibition is notably enriched for ones involved in the MAP Kinase (MAPK) pathway, whereas the decreasing population is dominated by genes involved in ribosomes and mitochondrial function. Since song stimulation itself triggers a decrease in miR-2954 expression followed by a delayed decrease in genes encoding ribosomal and mitochondrial functions, we suggest that miR-2954 may mediate some of the neurogenomic effects of song habituation

Health benefits from nature experiences depend on dose

Nature within cities will have a central role in helping address key global public health 3 challenges associated with urbanization. However, there is almost no guidance on how much 4 or how frequently people need to engage with nature, and what types or characteristics of 5 nature need to be incorporated in cities for the best health outcomes. Here we use a nature 6 dose framework to examine the associations between the duration, frequency and intensity of 7 exposure to nature and health in an urban population. We show that people who made long 8 visits to green spaces had lower rates of depression and high blood pressure, and those who 9 visited more frequently had greater social cohesion. Higher levels of physical activity were 10 linked to both duration and frequency of green space visits. A dose-response analysis for 11 depression and high blood pressure suggest that visits to outdoor green spaces of 30 minutes 12 or more during the course of a week could reduce the population prevalence of these illnesses 13 by up to 7% and 9% respectively. Given that the societal costs of depression alone in 14 Australia are estimated at AUD$12.6 billion per annum, savings to public health budgets 15 across all health outcomes could be immense.D.F.S. is supported through ARC Discovery Grant DP120102857 and the Centre of Excellence for Environmental Decisions (CEED, Australia); R.A.F. holds an ARC Future Fellowship; B.B.L. is supported through the CSIRO Land and Water Flagship; and K.J.G. is supported by NERC grant NE/J015237/1. J. Rhodes, K. Johansen and S. Wu contributed to the development of the vegetation data. Authors would like to thank the Brisbane City Council for providing GIS data layers, the Department of Science, Information Technology and Innovation and the Department of Natural Resources and Mines, QLD for providing access to the airborne LiDAR

Nuclear DNA content variation in life history phases of the Bonnemaisoniaceae (Rhodophyta)

Nuclear DNA content in gametophytes and sporophytes or the prostrate phases of the following species of Bonnemaisoniaceae (Asparagopsis armata, Asparagopsis taxiformis, Bonnemaisonia asparagoides, Bonnemaisonia clavata and Bonnemaisonia hamifera) were estimated by image analysis and static microspectrophotometry using the DNA-localizing fluorochrome DAPI (4′, 6-diamidino-2-phenylindole, dilactate) and the chicken erythrocytes standard. These estimates expand on the Kew database of DNA nuclear content. DNA content values for 1C nuclei in the gametophytes (spermatia and vegetative cells) range from 0.5 pg to 0.8 pg, and for 2C nuclei in the sporophytes or the prostrate phases range from 1.15-1.7 pg. Although only the 2C and 4C values were observed in the sporophyte or the prostrate phase, in the vegetative cells of the gametophyte the values oscillated from 1C to 4C, showing the possible start of endopolyploidy. The results confirm the alternation of nuclear phases in these Bonnemaisoniaceae species, in those that have tetrasporogenesis, as well as those that have somatic meiosis. The availability of a consensus phylogenetic tree for Bonnemaisoniaceae has opened the way to determine evolutionary trends in DNA contents. Both the estimated genome sizes and the published chromosome numbers for Bonnemaisoniaceae suggest a narrow range of values consistent with the conservation of an ancestral genome

Interplay of buried histidine protonation and protein stability in prion misfolding

Misofolding of mammalian prion proteins (PrP) is believed to be the cause of a group of rare and fatal neurodegenerative diseases. Despite intense scrutiny however, the mechanism of the misfolding reaction remains unclear. We perform nuclear Magnetic Resonance and thermodynamic stability measurements on the C-terminal domains (residues 90–231) of two PrP variants exhibiting different pH-induced susceptibilities to aggregation: the susceptible hamster prion (GHaPrP) and its less susceptible rabbit homolog (RaPrP). The pKa of histidines in these domains are determined from titration experiments, and proton-exchange rates are measured at pH 5 and pH 7. A single buried highly conserved histidine, H187/H186 in GHaPrP/RaPrP, exhibited a markedly down shifted pKa ~5 for both proteins. However, noticeably larger pH-induced shifts in exchange rates occur for GHaPrP versus RaPrP. Analysis of the data indicates that protonation of the buried histidine destabilizes both PrP variants, but produces a more drastic effect in the less stable GHaPrP. This interpretation is supported by urea denaturation experiments performed on both PrP variants at neutral and low pH, and correlates with the difference in disease susceptibility of the two species, as expected from the documented linkage between destabilization of the folded state and formation of misfolded and aggregated species

Sleep quality in middle-aged and elderly Chinese: distribution, associated factors and associations with cardio-metabolic risk factors

Background Poor sleep quality has been associated with increased risk of heart disease, diabetes and mortality. However, limited information exists on the distribution and determinants of sleep quality and its associations with cardio-metabolic risk factors in Chinese populations. We aimed to evaluate this in the current study. Methods A cross-sectional survey conducted in 2005 of 1,458 men and 1,831 women aged 50–70 years from urban and rural areas of Beijing and Shanghai. Using a questionnaire, sleep quality was measured in levels of well, common and poor. Comprehensive measures of socio-demographical and health factors and biomarkers of cardio-metabolic disease were recorded. These were evaluated in association with sleep quality using logistic regression models. Results Half of the population reported good sleep quality. After adjusting for potential confounders, women and Beijing residents had almost half the probability to report good sleep quality. Good physical and mental health (good levels of self-rated health (OR 2.48; 95%CI 2.08 to 2.96) and no depression (OR 4.05; 95%CI 3.12 to 5.26)) related to an increased chance of reporting good sleep quality, whereas short sleep duration (<7 hrs OR 0.10; 95%CI 0.07 to 0.14)) decreased it substantially. There were significant associations between levels of sleep quality and concentrations of plasma insulin, total and LDL cholesterol, and index of insulin resistance. Conclusion Levels of good sleep quality in middle-age and elderly Chinese were low. Gender, geographical location, self-rated health, depression and sleep quantity were major factors associated with sleep quality. Prospective studies are required to distil the factors that determine sleep quality and the effects that sleep patterns exert on cardio-metabolic health

A new concept for the combination of optical interferometers and high-resolution spectrographs

The combination of high spatial and spectral resolution in optical astronomy enables new observational approaches to many open problems in stellar and circumstellar astrophysics. However, constructing a high-resolution spectrograph for an interferometer is a costly and time-intensive undertaking. Our aim is to show that, by coupling existing high-resolution spectrographs to existing interferometers, one could observe in the domain of high spectral and spatial resolution, and avoid the construction of a new complex and expensive instrument. We investigate in this article the different challenges which arise from combining an interferometer with a high-resolution spectrograph. The requirements for the different sub-systems are determined, with special attention given to the problems of fringe tracking and dispersion. A concept study for the combination of the VLTI (Very Large Telescope Interferometer) with UVES (UV-Visual Echelle Spectrograph) is carried out, and several other specific instrument pairings are discussed. We show that the proposed combination of an interferometer with a high-resolution spectrograph is indeed feasible with current technology, for a fraction of the cost of building a whole new spectrograph. The impact on the existing instruments and their ongoing programs would be minimal.Comment: 27 pages, 9 figures, Experimental Astronomy; v2: accepted versio

Primary pyogenic spondylitis following kyphoplasty: a case report

<p>Abstract</p> <p>Introduction</p> <p>Only ten cases of primary pyogenic spondylitis following vertebroplasty have been reported in the literature. To the best of our knowledge, we present the first reported case of primary pyogenic spondylitis and spondylodiscitis caused by kyphoplasty.</p> <p>Case presentation</p> <p>A 72-year old Caucasian man with an osteoporotic compression fracture of the first lumbar vertebra after kyphoplasty developed sensory incomplete paraplegia below the first lumbar vertebra. This was caused by myelon compression following pyogenic spondylitis with a psoas abscess. Computed tomography guided aspiration of the abscess cavity yielded group C <it>Streptococcus</it>. The psoas abscess was percutaneously drained and laminectomy and posterior instrumentation with an internal fixator from the eleventh thoracic vertebra to the fourth lumbar vertebra was performed. In a second operation, corpectomy of the first lumbar vertebra with cement removal and fusion from the twelfth thoracic vertebra to the second lumbar vertebra with a titanium cage was performed. Six weeks postoperatively, the patient was pain free with no neurologic deficits or signs of infection.</p> <p>Conclusion</p> <p>Pyogenic spondylitis is an extremely rare complication after kyphoplasty. When these patients develop recurrent back pain postoperatively, the diagnosis of pyogenic spondylitis must be considered.</p