P2Y₂ Nucleotide Receptors Expressed Heterologously in Sympathetic Neurons Inhibit Both N-Type Ca²⁺ and M-Type K⁺ Currents

The P2Y₂ receptor is a uridine/adenosine triphosphate (UTP/ATP)-sensitive G-protein-linked nucleotide receptor that previously has been reported to stimulate the phosphoinositide signaling pathway. Messenger RNA for this receptor has been detected in brain tissue. We have investigated the coupling of the molecularly defined rat P2Y₂ receptor to neuronal N-type Ca²⁺ channels and to M-type K⁺ channels by heterologous expression in rat superior cervical sympathetic (SCG) neurons. After the injection of P2Y₂cRNA, UTP inhibited the currents carried by both types of ion channel. As previously reported [Filippov AK, Webb TE, Barnard EA, Brown DA (1997) Inhibition by heterologously expressed P2Y₂nucleotide receptors of N-type calcium currents in rat sympathetic neurones. Br J Pharmacol 121:849–851], UTP inhibited the Ca²⁺ current (I_{Ca(N)} by up to 64%, with an IC₅₀ of ∼0.5 μm. We now find that UTP also inhibited the K⁺_{M} current (I_{K(M)} by up to 61%, with an IC₅₀ of ∼1.5 μm. UTP had no effect on either current in neurons not injected with P2Y₂ cRNA. Structure–activity relations for the inhibition of I_{Ca(N)} and I_{K(M)} in P2Y₂ cRNA-injected neurons were similar, with UTP ≥ ATP > ITP ≫ GTP,UDP. However, coupling to these two channels involved different G-proteins: pretreatment withPertussis toxin (PTX) did not affect UTP-induced inhibition of I_{K(M)} but reduced inhibition of I_{Ca(N)} by ∼60% and abolished the voltage-dependent component of this inhibition. In unclamped neurons, UTP greatly facilitated depolarization-induced action potential discharges. Thus, the single P2Y₂ receptor can couple to at least two G-proteins to inhibit both Ca²⁺_{N} and K⁺_{M} channels with near-equal facility. This implies that the P2Y₂ receptor may induce a broad range of effector responses in the nervous system

Effets de l’incorporation du fondu de déchets de sachets plastiques sur la consistance du bitume et la stabilité du béton bitumineux

Les quantités de déchets plastiques produites au Bénin sont importantes, avec plus de 50% de sachets d’emballages. Cette situation provoque un problème environnemental majeur, en raison du caractère nonbiodégradable de ces derniers. Dans la perspective de leur recyclage à travers les procédés de construction, le présent article est consacré à l’analyse des caractéristiques requises du liant, la pénétrabilité, le point de ramollissement et l’adhésivité, formulé à base du bitume de référence 50/70 auquel est incorporée, à environ 170°C, de la poudre de sachets plastiques fondus, refroidis et finement broyés et la stabilité Marshall du béton bitumineux découlant.Pour 2 à 20% en masse d’incorporation de poudre de sachets plastiques dans le bitume, les différentes valeurs enregistrées ont révélé que la pénétrabilité, mesurée suivant la norme EN1426, diminue quand la teneur en poudre de sachets augmente donnant naissance à des liants bitumineux appartenant aux classes respectives 50/70, 40/60, 35/50, 30/45 et 20/30 alors que le point de ramollissement augmente. L’adhésivité est positivement améliorée avec l’accroissement de la teneur en sachet plastique au même titre que la stabilité Marshall du béton bitumineux découlant.Mots-clés : sachets plastiques, pénétrabilité, ramollissement, adhésivité, bitume, construction routière

The extent of groundwater use for domestic and irrigation activities in Thiririka sub-catchment, Gatundu South District, Kiambu County, Kenya

Population increase in Thiririka sub-catchment is causing high demand of water against limited supply. Currently, only 12,000 households out of 250,000 in the catchment have access to pipe water.  Groundwater offers the one of the available options to the limited and irregular supply of pipe water. This study aims to find out the extent to which groundwater as alternative source of water for both domestic and irrigation activities is explored in the Thiririka sub-catchment. To achieve this objective, a field  survey was conducted using semi-structured questionnaire to seek the extent to which individuals and  households use groundwater. The study indicated a very low and adopted use of groundwater in the  catchment. Only 36.7% of the various households visited use groundwater for domestic activities and  13.30% for irrigation purposes. It was found out that residents perception on groundwater to be polluted  and therefore not safe for domestic activities, lack of cash availability for individuals who wish to  construct wells at their homes and lack of awareness and education on the benefits of groundwater are  some of the challenges contributing to the low use of groundwater in the Thiririka sub-catchment. It was therefore, recommended that education on the benefits of groundwater by the Gatundu South Water  Services and Sanitation office and other NGOs be intensified to the residents of Thiririka sub-catchment and more community boreholes and wells should be provided to the communities by the government, churches and NGOs, beside the pipe connections.  Key words: Groundwater, Groundwater use, Thiririka sub-catchment, Kenya, Millennium Development Goal

Floristic diversity and vegetation analysis of Brassica nigra (L.) Koch communities

The floristic composition and species diversity of Brassica nigra communities were investigated in Beni Suef Governorate, Egypt. In 46 stands, a total of 49 species belonging to 42 genera and 18 families were recorded. Vegetation classification and ordination distinguished seven groups: two in reclaimed land only, three groups in old cultivated land only, and two that occurred in both types of land. The species that dominated these groups were Brassica nigra, Sonchus oleraceus, Beta vulgaris, Cichorium endivia, Euphorbia helioscopia and Anagallis arvensis. The highest species diversity was mainly in groups from reclaimed land, and in wheat compared to other crops. Edaphic factors, especially soil texture, CaCO3 and organic carbon, contributed significantly to explaining the distribution of some weed species, but not with that of B. nigra. The allelopathic potential of Brassica nigra reported in previous studies did not seem to play a role in community composition.Keywords: allelopathy, Brassica nigra, vegetation, TWINSPAN, weed diversit

Insecticide Use Practices in Cocoa Production in Four Regions in Ghana

Chemical control of insect pests of cocoa started in 1950, and insecticides from the various classes have been recommended and used by farmers since then. Presently, Imidacloprid (Confidor®), Bifenthrin (Akatemaster®) and Thiamethoxam (Actara®) are recommended by Ghana Cocoa Board (COCOBOD) for insect pest management. A survey was conducted in the Ashanti, Eastern, Volta and Western regions of Ghana using questionnaires and farm visits of 147 cocoa farmers’ fields to gather information on insecticide use practices by farmers. The survey showed that the farmers used mostly Imidacloprid and Bifenthrin insecticides and the frequency of application was more than that recommended by COCOBOD. Among the three recommended insecticides, 43% each of the farmers across the three regions used either Confidor® or Akatemaster® whilst the remaining 14% used Actara®. The number of years farmers had consistently used a particular insecticide ranged between 5 and 16 years. Whilst some cocoa farmers do not apply insecticides to their farms, others, however, do as many as 11 applications in a year. Most of the insecticides used are classified as class II under WHO Hazard category, and the farmers used very minimal protective clothing during pesticides application. The results of this study show that there is the need to intensify education on safe handling and use of pesticides to reduce pesticide abuse, especially by cocoa farmers, in order to sustain effective management of pests and protect farmers, consumers and the environment

Comparison of respondent-reported and sensor-recorded latrine utilization measures in rural Bangladesh: a cross-sectional study.

Background: Health improvements realized through sanitation are likely achieved through high levels of facilities utilization by all household members. However, measurements of sanitation often rely on either the presence of latrines, which does not guarantee use, or respondent-reported utilization of sanitation facilities, which is prone to response bias. Overstatement of sanitation metrics limits the accuracy of program outcome measures, and has implications for the interpretation of related health impact data. Methods: We conducted a cross-sectional study of 213 households in 14 village water, sanitation and hygiene committee clusters throughout rural Bangladesh and used a combined data- and relationship-scale approach to assess agreement between respondent-reported latrine utilization and sensor-recorded measurement. Results: Four-day household-level respondent-reported defecation averaged 28 events (inter-quartile range [IQR] 20-40), while sensor-recorded defecation averaged 17 events (IQR 11-29). Comparative analyses suggest moderately high accuracy (bias correction factor=0.84), but imprecision in the data (broad scatter of data, Pearson's r=0.35) and thus only weak concordance between measures (ρc=0.29 [95% BCa CI 0.15 to 0.43]). Conclusions: Respondent-reported latrine utilization data should be interpreted with caution, as evidence suggests use is exaggerated. Coupling reported utilization data with objective measures of use may aid in the estimation of latrine use

Cost-effectiveness of noninvasive liver fibrosis tests for treatment decisions in patients with chronic hepatitis C

The cost-effectiveness of noninvasive tests (NITs) as alternatives to liver biopsy is unknown. We compared the cost-effectiveness of using NITs to inform treatment decisions in adult patients with chronic hepatitis C (CHC). We conducted a systematic review and meta-analysis to calculate the diagnostic accuracy of various NITs using a bivariate random-effects model. We constructed a probabilistic decision analytical model to estimate health care costs and outcomes (quality-adjusted life-years; QALYs) using data from the meta-analysis, literature, and national UK data. We compared the cost-effectiveness of four treatment strategies: testing with NITs and treating patients with fibrosis stage ≥F2; testing with liver biopsy and treating patients with ≥F2; treat none; and treat all irrespective of fibrosis. We compared all NITs and tested the cost-effectiveness using current triple therapy with boceprevir or telaprevir, but also modeled new, more-potent antivirals. Treating all patients without any previous NIT was the most effective strategy and had an incremental cost-effectiveness ratio (ICER) of £9,204 per additional QALY gained. The exploratory analysis of currently licensed sofosbuvir treatment regimens found that treat all was cost-effective, compared to using an NIT to decide on treatment, with an ICER of £16,028 per QALY gained. The exploratory analysis to assess the possible effect on results of new treatments, found that if SVR rates increased to >90% for genotypes 1-4, the incremental treatment cost threshold for the "treat all" strategy to remain the most cost-effective strategy would be £37,500. Above this threshold, the most cost-effective option would be noninvasive testing with magnetic resonance elastography (ICER=£9,189). Conclusions: Treating all adult patients with CHC, irrespective of fibrosis stage, is the most cost-effective strategy with currently available drugs in developed countries. © 2014 The Authors

The skin you're in: Design of experiments optimization of lipid nanoparticle self-amplifying RNA formulations in human skin explants

Messenger RNA (mRNA) is a promising tool for biotherapeutics, and self-amplifying mRNA (saRNA) is particularly advantageous as it results in abundant protein expression and production is easily scalable. While mRNA therapeutics have been shown to be highly effective in small animals, the outcomes do not scale linearly when these formulations are translated to dose-escalation studies in humans. Here, we utilize a Design of Experiments (DoE) approach to optimize the formulation of saRNA lipid nanoparticles in human skin explants. We first observed that luciferase expression from saRNA peaked after 11 days in human skin. Using DoE inputs of complexing lipid identity, lipid nanoparticle dose, lipid concentration, particle concentration, and ratio of zwitterionic to cationic lipids, we optimized the saRNA-induced luciferase expression in skin explants. Lipid identity and lipid concentration were found to be significant parameters in the DoE model, and the optimized formulation resulted in ~7-fold increase in luciferase expression relative to initial DOTAP formulation. Using flow cytometry, we observed that optimized formulations delivered the saRNA to ~2% of the resident cells in the human skin explants. Although immune cells make up only 7% of the total population of cells in skin, immune cells were found to express ~50% of the RNA. This study demonstrates the powerful combination of using a DoE approach paired with clinically relevant human skin explants to optimize nucleic acid formulations. We expect that this system will be useful for optimizing both formulation and molecular designs of clinically translational nucleic acid vaccines and therapeutics

Heparan sulfate phage display antibodies recognise epitopes defined by a combination of sugar sequence and cation binding.

Phage display antibodies are widely used to follow heparan sulfate (HS) expression in tissues and cells. We demonstrate by ELISA, that cations alter phage display antibody binding profiles to HS and this is mediated by changes in polysaccharide conformation, demonstrated by circular dichroism spectroscopy. Native HS structures, expressed on the cell surfaces of neuroblastoma and fibroblast cells, also exhibited altered antibody binding profiles following exposure to low mM concentrations of these cations. Phage display antibodies recognise conformationally-defined HS epitopes, rather than sequence alone, as has been assumed, and resemble proteins in being sensitive to changes in both charge distribution and conformation following binding of cations to HS polysaccharides

Prospective mental imagery as its link with anxiety and depression in prisoners

Mental imagery is known to play a key role in the development and maintenance of depression and anxiety. Prisoners commonly experience psychological distress, but interventions to address this are currently lacking. We aimed to examine the link between prospective mental imagery and anxiety and depression among prisoners. One hundred twenty-three male prisoners from a Category C prison in southwest England participated in the study. They completed the Centre for Epidemiologic Studies Depression Scale (CES-D) and the General Anxiety Disorder Scale (GAD-7) to measure whether they experience depression and/or anxiety symptoms. Furthermore, they completed additional questionnaires to evaluate their prospective mental imagery. Results showed that 67.5% of prisoners presented with more depression symptoms and 27.7% with more anxiety symptoms. Supporting earlier findings, our data revealed that some dimensions of prospective mental imagery were significantly related with increased anxiety and depression symptoms in prisoners. Namely, intrusive negative personally relevant imagery was a positive predictor and likelihood of positive events a negative predictor of both anxiety and depression symptoms. The perceived likelihood of negative events was a positive predictor of depression. Intrusive verbal thought was a positive predictor of anxiety. The obtained results suggest the need to develop interventions not only targeting the reduction of prospective negative imagery but also the enhancement of positive mental imagery