Validation of a method for measuring sperm quality and quantity in reproductive toxicity tests with pair-breeding male fathead minnows (Pimephales promelas)

This article originally appeared in the ILAR e-Journal. It is reprinted with permission from the ILAR Journal, Institute for Laboratory Animal Research, National Research Council, Washington DC (www.nationalacademies.org/ilar).The fathead minnow (Pimephales promelas) is an OECD-proposed test species routinely used in reproductive toxicity trials with suspected endocrine-disrupting compounds (EDCs). The basic fecundity, endocrinology, and histopathology of reproductively active male and female fathead minnows has been well characterized, but there are few studies of the utility of male sperm concentration and motility as endpoints for use in reproductive trials. The purpose of this study was to (1) characterize the baseline sperm concentration and motility of pair-breeding male fathead minnows over their spawning cycle and (2) determine whether a repeated and nondestructive sperm sampling protocol would influence the baseline fecundity of the fish. Pair-breeding male fathead minnows that underwent sampling for milt three times a week for 4 weeks exhibited no significant changes in milt volume, sperm concentration, or motility parameters up to 6 days after each spawning event. The repeated sperm sampling procedure did, however, cause a significant lowering of spawning frequencies, although this decline did not correlate with effects on fecundity as there were no significant changes in the mean total numbers of eggs laid, fertilization, and hatching successes. This study confirmed the presence of a stable background of sperm concentration and motility parameters of pair-breeding male fathead minnows under reference conditions. The absence of any inherent “cycling” in the magnitude of these parameters over the spawning period suggests that sperm concentration and motility could be useful measures of male reproductive toxicity at the termination of tests in which pair-breeding males are at varying days post spawn.The research described was funded by the EU project Comparative Research on Endocrine Disrupters (COMPRENDO) Institute of Zoology Regents Park, London, contract No. EVK1-CT-2002-00129E

Behavior of Reinforced Reactive Powder Concrete Two-Way Slabs under Static and Repeated Load

This paper studies the behavior of reinforced Reactive Powder Concrete (RPC) two-way slabs under static and repeated load. The experimental program included testing six simply supported RPC two-way slabs of 1000 mm length, 1000 mm width, and 70 mm thickness. All the tested specimens were identical in their material properties, and reinforcement details except their steel fibers content. They were cast in three pairs, each one had a different steel fibers ratio (0.5 %, 1 %, and 1.5 %) respectively. In each pair, one specimen was tested under static load and the other under five cycles of repeated load (loading-unloading). Static test results revealed that increasing steel fibres volume fraction from 0.5 % to 1 % and from 1% to 1.5%, led to an increase in the: first crack load by (32.2 % and 52.3 %), ultimate load by (36.1 % and 17.0 %), ultimate deflection by (33.6 % and 3.4 %), absorbed energy by (128 % and 20.2 %), and the ultimate strain by (1.1 % and 6.73 %). It also increased the stiffness and the ductility of the specimens especially at the final stages of loading. Additionally, it delayed the propagation of the cracks, controlled their growth, kept the integrity of the specimens at post cracking stage, and avoided their ruin at the failure stage through its “bridging” effect. For the repeated load test, applying five cycles of repeated load to the steel fiber reinforced RPC two-way slab specimens led to a decreasing in the ultimate load capacity, ultimate deflection, ultimate strain, and absorbed energy in a comparison with the corresponding static test specimens, and that because of the loading-unloading process which causes a fluctuation of stresses and more damages in concrete. Increasing the steel fibers volume fractions decreased the dissipated energy of the specimens that subjected to a repeated load, where the difference percent of dissipated energy between the first and second cycles of (R0.5 %, R1 %, and R1.5 %) specimens were (68.0 %, 46.2%, and 32.4%) respectively

Évaluation de la sensibilité de sept clones de palmier à huile (Elaeis guineensis Jacq.) à Coelaenomenodera lameensis Berti et Mariau (Coleoptera, Chrysomelidae) Konan J.

Objectifs : Évaluer la sensibilité de 7 clones d’Elaeis guineensis à Coelaenomenodera lameensis (Coleoptera : Hispinae) et estimer les dégâts occasionnés par l’insecte au terme d’un cycle de développement complet sur chaque type de matériel clonal.Méthodologies et Résultats : des insectes adultes de C. lameensis ont été transposés sur des folioles de clones d’Elaeis guineensis isolés dans des manchons. L’évolution des insectes a été ensuite observée à chaque étape du cycle normal de développement de C. lameensis. Les dégâts provoqués par l’insecte ont été estimés par le rapport entre la surface de foliole attaquée et la surface totale de foliole. Les résultats ont montré que certains clones étaient moins favorables au développement de l’insecte que d’autres. Le clone LMC247, avec 53,80 % ± 2,56 de surface foliaire attaquée, a été plus sensible à l’insecte que les autres clones LMC159, LMC161, LMC022, LMC010, LMC270 et LMC291 où les dégâts observés ont été en dessous de 25%..Conclusion et Application : au regard des résultats, il ressort que le développement de C. lameensis est influencé par le type de matériel clonal. Les dégâts sur les clones testés ont été généralement de faible intensité. Cette approche expérimentale, laisse présager de bonnes perspectives pour la lutte génétique contre C. lameensis.. En effet, plus de 300 clones de palmier ont déjà été crées en Côte d’Ivoire. Un criblage élargi à l’ensemble de ce matériel va permettre d’identifier à terme des clones performants pour contrôler le ravageur, au regard de l’homogénéité de ce type de matériel végétal.Mots clés : clone, palmier à huile, lutte génétique, Coelænomenodera lameensisEvaluation of seven oil palm clones (Elaeis guineensis Jacq.) sensibility to Coelaenomenodera lameensis Berti and Mariau (Coleoptera, Chrysomelidae)Objective: this study aims to evaluate seven oil palm clones sensibility to Coelaenomenodera lameensis (Coleoptera: Hispinae) and to estimate the damage caused by this insect on each type of clonal material.Methods and results: adult insects of C. lameensis were transposed on Elaeis guineensis clones leaflets isolated in canvas bags. Insect evolution was observed at each stage of normal development cycle of C. lameensis. The damage caused by the insect was estimated using the ratio of the surface of leaflet attacked and the total surface of leaflet. The results showed that some clones were less favorable to the development of C. lameensis than others. The clone LMC247, with 53.80 ± 2.56% of leaf surface attacked was more susceptible to C. lameensis than the other clones LMC159, LMC161, LMC022, LMC010, LMC270 and LMC291. For these clones, the damages noted were below 25% of leaf area attacked.Conclusion and application: the results showed that C. lameensis development depended of the clones. Overall, a low intensity of damage was observed on the leaflet of the clones. This experimental approach suggests good projection for genetic control of C. lameensis with oil palm clone material. Indeed, more than 300 oil palm clones have already been established in Côte d'Ivoire. The screening of this material can help selecting performing material to control the pest due to the homogeneity of this type of plant material. Key words: clone, oil palm, genetic control, Coelænomenodera lameensi

Amine-functionalized MCM-48 as Adsorbent of Zn2+ and Ni2+ Ions

A compound, 3-aminopropyltrimetoxy silane, has been used to modify mesoporous silica, MCM-48. The modified silica (NH2-MCM-48) was utilized to remove Zn2+ and Ni2+ ions from solutions. The mesoporous material was synthesized in the alkaline solution. Characterization of the unmodified materials was conducted by X-ray diffraction and FT-IR spectroscopy. The ions adsorbed on NH2-MCM-48 were studied at various pHs, contact times and initial ions concentrations. An Atomic Absorption Spectrophotometer (AAS) measured the ions content in the solution.. Pseudo-first-order and pseudo-second-order models performed the kinetic adsorption. The adsorption isotherm was examined by Langmuir and Freundlich isotherms. The result found that optimum contact time for the adsorption of Zn2+ ion was lower than that for Ni2+ ion. The adsorption followed the pseudo-second-order model with the adsorption rate of 4.56x10-2 g mg-1 min-1 for Zn2+ ion and 7x10-4 g mg-1 min-1 for Ni2+ ion. The optimum pH was 6 and 4 for Zn2+ and Ni2+ adsorption, respectively. The uptake of both ions from solutions by NH2-MCM-48 fixed better the Langmuir than the Freundlich model with the adsorption capacity of 0.55 and 0.43 mmol g-1, correspondingly. This research work provides valuable information on the interaction between the ions and the functional group of adsorbent

Traffic Safety in Sudan: Magnitude and Future Challenges

The performance of road safety in Sudan has generally deteriorated over the last few years as accident rates have witnessed a tremendous increase. The number of road accidents was 23850 in 2001 rising to a total of 38515 in 2005, then to 61428 accidents in 2010. The 2010 fatality rate of 38 per 10,000 registered vehicles is very high compared to Arab, developing and developed countries. This paper reviews the magnitude, trends and characteristics of road traffic accidents in Sudan in order to provide a better understanding of the road safety trauma. It discusses the future trends and challenges which are expected to have significant bearing on both short and long-term traffic safety development. Finally short term remedial measures and long term National Road Safety Strategy are presented and recommended for implementation

Functional constraints on the constitutive androstane receptor inferred from human sequence variation and cross-species comparisons

<p>Abstract</p> <p>Members of the NR1I subfamily of nuclear receptors play a role in the transcriptional activation of genes involved in drug metabolism and transport. NR1I3, the constitutive androstane receptor (CAR), mediates the induction of several genes involved in drug response, including members of the <it>CYP3A</it>, <it>CYP2B </it>and <it>UGT1A </it>subfamilies. Large inter-individual variation in drug clearance has been reported for many drug metabolising enzyme genes. Sequence variation at the <it>CAR </it>locus could potentially contribute to variation in downstream targets, as well as to the substantial variation in expression level reported. We used a comparative genomics-based approach to select resequencing segments in 70 subjects from three populations. We identified 21 polymorphic sites, one of which results in an amino acid substitution. Our study reveals a common haplotype shared by all three populations which is remarkably similar to the ancestral sequence, confirming that CAR is under strong functional constraints. The level and pattern of sequence variation is approximately similar across populations, suggesting that interethnic differences in drug metabolism are not likely to be due to genetic variation at the <it>CAR </it>locus. We also identify several common non-coding variants that occur at highly conserved sites across four major branches of the mammalian phylogeny, suggesting that they may affect <it>CAR </it>expression and, ultimately, the activity of its downstream targets.</p

Essai de lutte contre oryctes monoceros olivier (coleoptera : dynastidae) par l’utilisation de l’acide 4-méthyloctanoïque en côte -d’ivoire

(Arecaceae), en Côte d’Ivoire. Pour lutter contre ce ravageur, l’acide 4-methyloctanoïque a été initié. Au cours de ces travaux, 3 types de diffuseurs (Da, Db, Dc) contenant les différentes doses ont été expérimentés. L’étude a été menée sur 9 mois repartie sur 4 phases dont 1 mois sans diffuseurs, 4 mois avec diffuseurs, 2 mois retrait desdiffuseurs et 2 mois post diffuseurs. Les visites des cocotiers ont été effectuées 3 fois par semaine avec extraction des insectes des galeries en notant les caractéristiques climatiques et le sexe des insectes. Les diffuseurs ont été pesés au début et chaque mois pendant la phase avec diffuseurs. On note que les trois types de diffuseurs ont la même efficacité contre les attaques de O. monoceros mais le diffuseur Dc, caractérisé par la dose faible, est économiquement plus avantageux et pourrait être vulgarisé auprès des paysans, pour la protection de leurs plantations.Mots clés : Cocos nucifera, Oryctes monoceros, Diffuseurs, Acide 4-méthyloctanoïqueOryctes monoceros Olivier is one of the most dangerous pests of young coconuts Cocos nucifera Linne (Arecaceae) in Côte-d’Ivoire. In order to reduce their populations, 4-methyloctanoïc acid was initiated. In this work, 3 different types of diffusers (Da, Db, Dc) was tested. The study over nine months covered four phases with one month (without diffusers), four month (with diffusers), two month (diffuser withdrawal) and two month (post diffuser). Coconuts were visited 3 twice in a week by collecting insects of galleries and wrote down climatic characteristics, sex of insects. Diffusers were weighted at the beginning and every month during phase with diffusers. We notice that three types of diffusers have the same effectiveness against O. monoceros attacks, diffuser Dc, characterized by a low concentration, is economically more reasonable and could be recommended to the farmer for the protection of their plantations

Child‐level double burden of malnutrition in the MENA and LAC regions: Prevalence and social determinants

Although the prevalence of obesity has rapidly increased in the low‐ and middle‐income countries of the Middle East and North Africa (MENA) and Latin America and the Caribbean (LAC) regions, child undernutrition remains a public‐health challenge. We examined region‐specific sociodemographic determinants of this double burden of malnutrition, specifically, the co‐occurrence of child stunting and overweight, using Demographic and Health Survey and Multiple Indicator Cluster Survey data (2003–2016) from 11 countries in the MENA (n = 118,585) and 13 countries in the LAC (n = 77,824) regions. We used multiple logistic regressions to model region‐specific associations of maternal education and household wealth with child nutritional outcomes (6–59 months). The prevalence of stunting, overweight, and their co‐occurrence was 24%, 10%, and 4.3% in children in the MENA region, respectively, and 19%, 5%, and 0.5% in children in the LAC region, respectively. In both regions, higher maternal education and household wealth were significantly associated with lower odds of stunting and higher odds of overweight. As compared with the poorest wealth quintiles, decreased odds of co‐occurring stunting and overweight were observed among children from the second, third, and fourth wealth quintiles in the LAC region. In the MENA region, this association was only statistically significant for the second wealth quintile. In both regions, double burden was not statistically significantly associated with maternal education. The social patterning of co‐occurring stunting and overweight in children varied across the two regions, indicating potential differences in the underlying aetiology of the double burden across regions and stages of the nutrition transition.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154671/1/mcn12923_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154671/2/mcn12923.pd

Asymptomatic colonization of Staphylococcus aureus with intermediate resistance to vancomycin harboring vanB resistance gene

Objective: Vancomycin has been used worldwide due to empirical therapy against methicillin-resistant Staphylococcus aureus infections. As a result a selective pressure that favors the outgrowth of vancomycin intermediate S. aureus clones will be created. This study was carried out to evaluate vancomycin resistance pattern of S. aureus in Jordan.Methods: A total of 1179 samples, including 566 (48%) from human and 613 (52%) from animals were examined for the presence of S. aureus using standard biochemical tests and polymerase chain reaction (PCR) amplification of coa gene. Resistance to antibiotics was determined by the disk diffusion method. Methicillin resistance strains were tested for vancomycin resistance by minimal inhibitory concentration (MIC), E- test, and the results were confirmed by amplification of van genes, and Pulsed-field gel electrophoresis (PFGE).Results: The prevalence of S. aureus among human source was: 19.35%, 14%, and 8.8% for nasal, nail, and skin, respectively, and for animal sources 27.3%, 5.51%, and 15.86% for milk, nasal, and meat, respectively. Four VISA strains (1.87%) were found to colonize human nares, nails, and skin with vancomycin MIC of 4-8 μg/ml. Van B resistance gene was detected and PFGE with SmaI-digested VISA genomic DNA revealed two different pulsotypes.Conclusion: This is believed to be the first report of VISA strains containing vanB gene isolated from a routine carriage survey. Effective screening directed to persons colonized with VISA should therefore be a priority.Â