Contribution à l’étude de l’impact d’un fongicide (Dithiocarbamate de manganèse : Manèbe) sur quelques paramètres de la fertilité masculine chez le lapin : Oryctolagus cuniculus

Ce travail vise à étudier l’effet d’un fongicide organométallique -le Manèbe- sur les paramètres de la fertilité chez le lapin male Oryctolagus cuniculus. Le fongicide a été appliqué a raison de deux doses: 1g /L et 2 g /L pendant 04 semaines successives. Les paramètres de fertilité y compris le poids testiculaire, quelques caractères biologiques des spermatozoïdes et le taux de la testostérone ont été étudiés. Les résultats révèlent qu’il y a une diminution significative dans le poids des testicules, la concentration et la mobilité des spermatozoïdes, et une augmentation significative dans les malformations morphologiques des spermatozoïdes chez les individus traités. D’autre part l’administration du Manèbe entraîne une diminution significative dans le taux de la testostérone.Mots-clés : Environnement, manèbe, lapin, fertilite - toxicite

Impact of polyphenolic extracts on resistance to fungal contamination in dry bean grains

From their significant roles against the biotic and abiotic stresses, polyphenols have aroused a growing interest for a possible application in food industry. The aim of this study was the evaluation of antifungal activity of polyphenols extracted from two varieties of dry bean, presenting white (Tima) and red (MGT djedida) color. Determination of moisture for the two varieties showed that these grains are favorable for moulds growth. Purification and microscopic study of the isolated strains from beans allowed the identification of six moulds genera: Alternaria, Aspergillus, Moniliella, Fusarium, Penicillium and Rhizopus. Extraction of total polyphenols was carried by a polar solvent and their quantification was based on the reaction of Folin Ciocalteu. The total polyphenolic content was 0.40 ± 0.005 mg EAG/g for the red variety and 0.27 ± 0.005 mg EAG/g for the white variety. The antifungal activity carried by the methods of direct contact, dilution, and antifungal index (IA100) demonstrated the antifungal capacity of polyphenols; most sensitive strains isolated are Alternaria sp., Moniliella sp. and Rhizopus sp.. The most active polyphenols are polyphenols extracted from presumably healthy red grains. Our results lend support of the creation of varieties bean high in polyphenols, which act as natural preservatives and bio-effective agents, and offer an alternative to chemical agents for protection of harvested beans in storage structures.Keywords: Polyphenols, antifungal activity, dry beanAfrican Journal of Biotechnology Vol. 12(20), pp. 2978-298

Simultaneous allocation of multiple distributed generation and capacitors in radial network using genetic-salp swarm algorithm

In recent years, the problem of allocation of distributed generation and capacitors banks has received special attention from many utilities and researchers. The present paper deals with single and simultaneous placement of dispersed generation and capacitors banks in radial distribution network with different load levels: light, medium and peak using genetic-salp swarm algorithm. The developed genetic-salp swarm algorithm (GA-SSA) hybrid optimization takes the system input variables of radial distribution network to find the optimal solutions to maximize the benefits of their installation with minimum cost to minimize the active and reactive power losses and improve the voltage profile. The validation of the proposed hybrid genetic-salp swarm algorithm was carried out on IEEE 34-bus test systems and real Algerian distributed network of Djanet (far south of Algeria) with 112-bus. The numerical results endorse the ability of the proposed algorithm to achieve a better results with higher accuracy compared to the result obtained by salp swarm algorithm, genetic algorithm, particle swarm optimization and the hybrid particle swarm optimization algorithms.В последние годы задача размещения распределенной генерации и батарей конденсаторов привлекает особое внимание многих организаций и исследователей. В данной работе рассмотрены отдельное и совместное размещение распределенной генерации и батарей конденсаторов в радиальной распределительной сети при различных уровнях нагрузки: слабом, среднем и пиковом с использованием алгоритма генетического роя сальпов (genetic-salp swarm algorithm). Разработанный алгоритм гибридной оптимизации генетического роя сальпов (GA-SSA) использует системные входные переменные радиальной распределительной сети для поиска оптимальных решений с целью максимизации преимуществ их установки с минимальными затратами для минимизации потерь активной и реактивной мощности и улучшения профиля напряжения. Тестирование предложенного алгоритма гибридной оптимизации генетического роя сальпов было проведено на экспериментальных 34-шинных системах IEEE и реальной 112-шиной алжирской распределенной сети Джанета (крайний юг Алжира). Численные результаты подтверждают способность предложенного алгоритма достигать лучших результатов с большей точностью по сравнению с результатом, полученным методом роя сальпов, генетическим алгоритмом, оптимизацией роя частиц и алгоритмами гибридной оптимизации роя частиц

The floristic and chemical composition of the grass of permanent grasslands in north-east Algeria : A composição florística e química da erva dos prados permanentes no nordeste da Argélia

This work shows that the botanical composition of the meadows studied according to the region and that the grass family is less well represented in R.Souk (13%) and Ain Khiar (14%) than in Oued El-Hout (18%). The Ain-Khiar region is dominated by leuminous plants (43%). Thus, all the grasslands studied do not follow the laws classically described for grasslands, namely the dominance of grasses followed by legumes. Differences were observed between the chemical compositions of grasslands. The Ain-Khiar region is distinguished in particular by higher average contents of mineral matter (24.6% DM) and crude protein (14.32% DM)

Effects of extractable protein hydrolysates, lipids, and polyphenolic compounds from pearl millet (Pennisetum glaucum (L.) R. BR.) whole grain flours on starch digestibility

Pearl millet and other minor cereal production is marginalized in the Sahara of Algeria (Tidikelt and Hoggar regions). Their productions in these areas depend on traditional harvesting and processing. Pearl millet seeds are used as animal feed and rarely for human consumption. This work was to assess the starch digestion of pearl millet cultivated in the arid areas of Algeria. The seeds from this cereal could provide broad potential benefits to human health. However, their digestion properties have not been reported. Therefore, in this study, the in-vitro starch digestibility of pearl millet flour and the effect of processing on the expected glycemic index (eGI) were investigated. Grains from six pearl millet samples were chosen from two regions: Tidikelt and Hoggar. Five flours were prepared by dry milling (MF) and different treatments after dry milling such as extraction of phenolic compounds (MF-PP), lipid extraction (MF-L), protein hydrolysate extraction (MF-P) or lipid plus protein hydrolysate extraction (MF-L-P). The flours were then subjected to digestion, and the effects of grain treatments on the in vitro starch digestion were investigated. For all pearl millet samples, the kinetics of in vitro starch digestion displayed first-order model as substrates were digested to different extents; k (kinetic constant), C∞ (percentage of starch hydrolyzed at infinite time), HI (hydrolysis index) and eGI (expected glycemic index) of the samples were also calculated. Significant increases in C∞, HI and eGI (P<0.05) of the samples were observed after extraction of proteins or proteins plus lipids from flour. Four flours obtained after lipid extraction and five flours from extraction of phenolic compounds had low glycemic index (<55), with values ranging between 31.36 and 44.97. In contrast, flours obtained from protein hydrolysate extraction or lipids plus protein hydrolysates had the highest glycemic index (>69), with values ranging between 77.50 and 121.44. This study confirmed that some of the processed pearl millet seed flours have acceptable nutritional values suitable for human health and nutrition due to the low glycemic index values

Polycomb Mediated Epigenetic Silencing and Replication Timing at the INK4a/ARF Locus during Senescence

International audienceBACKGROUND: The INK4/ARF locus encodes three tumor suppressor genes (p15(Ink4b), Arf and p16(Ink4a)) and is frequently inactivated in a large number of human cancers. Mechanisms regulating INK4/ARF expression are not fully characterized. PRINCIPAL FINDINGS: Here we show that in young proliferating embryonic fibroblasts (MEFs) the Polycomb Repressive Complex 2 (PRC2) member EZH2 together with PRC1 members BMI1 and M33 are strongly expressed and localized at the INK4/ARF regulatory domain (RD) identified as a DNA replication origin. When cells enter senescence the binding to RD of both PRC1 and PRC2 complexes is lost leading to a decreased level of histone H3K27 trimethylation (H3K27me3). This loss is accompanied with an increased expression of the histone demethylase Jmjd3 and with the recruitment of the MLL1 protein, and correlates with the expression of the Ink4a/Arf genes. Moreover, we show that the Polycomb protein BMI1 interacts with CDC6, an essential regulator of DNA replication in eukaryotic cells. Finally, we demonstrate that Polycomb proteins and associated epigenetic marks are crucial for the control of the replication timing of the INK4a/ARF locus during senescence. CONCLUSIONS: We identified the replication licencing factor CDC6 as a new partner of the Polycomb group member BMI1. Our results suggest that in young cells Polycomb proteins are recruited to the INK4/ARF locus through CDC6 and the resulting silent locus is replicated during late S-phase. Upon senescence, Jmjd3 is overexpressed and the MLL1 protein is recruited to the locus provoking the dissociation of Polycomb from the INK4/ARF locus, its transcriptional activation and its replication during early S-phase. Together, these results provide a unified model that integrates replication, transcription and epigenetics at the INK4/ARF locus

Empirical equations for the estimation of natural mortality in Mediterranean teleosts

Empirical relationships were established linking estimates of the instantaneous rate of natural mortality (M), the von Bertalanffy growth parameters, L sub( infinity ) (or W sub( infinity )) and K, and annual mean water temperature in 56 stocks of Mediterranean teleosts fish. It is suggested that these relationships generate for these fish more reliable estimates of M than the widely-used model of Pauly (1980, J. Cons. CIEM 33(3):175-192), which was based on 175 fish stocks, but included only five stocks from the Mediterranean

Empirical equations for the estimation of natural mortality in Mediterranean teleosts

Natural mortality, Statistical analysis, Mediterranean Region, Teleostei

Dermal fibroblasts in Hutchinson-Gilford progeria syndrome with the lamin A G608G mutation have dysmorphic nuclei and are hypersensitive to heat stress

Background: Hutchinson-Gilford progeria syndrome (HGPS, OMIM 176670) is a rare sporadic disorder with an incidence of approximately 1 per 8 million live births. The phenotypic appearance consists of short stature, sculptured nose, alopecia, prominent scalp veins, small face, loss of subcutaneous fat, faint mid-facial cyanosis, and dystrophic nails. HGPS is caused by mutations in LMNA, the gene that encodes nuclear lamins A and C. The most common mutation in subjects with HGPS is a de novo single-base pair substitution, G608G (GGC>GGT), within exon 11 of LMNA. This creates an abnormal splice donor site, leading to expression of a truncated protein. Results: We studied a new case of a 5 year-old girl with HGPS and found a heterozygous point mutation, G608G, in LMNA. Complementary DNA sequencing of RNA showed that this mutation resulted in the deletion of 50 amino acids in the carboxyl-terminal tail domain of prelamin A. We characterized a primary dermal fibroblast cell line derived from the subject's skin. These cells expressed the mutant protein and exhibited a normal growth rate at early passage in primary culture but showed alterations in nuclear morphology. Expression levels and overall distributions of nuclear lamins and emerin, an integral protein of the inner nuclear membrane, were not dramatically altered. Ultrastructural analysis of the nuclear envelope using electron microscopy showed that chromatin is in close association to the nuclear lamina, even in areas with abnormal nuclear envelope morphology. The fibroblasts were hypersensitive to heat shock, and demonstrated a delayed response to heat stress. Conclusion: Dermal fibroblasts from a subject with HGPS expressing a mutant truncated lamin A have dysmorphic nuclei, hypersensitivity to heat shock, and delayed response to heat stress. This suggests that the mutant protein, even when expressed at low levels, causes defective cell stability, which may be responsible for phenotypic abnormalities in the disease

Starch digestion in pearl millet (<i>Pennisetum glaucum</i> (L.) R. Br.) flour from arid area of Algeria

To assess the nutritive value of minor cereals cultivated in arid areas of Algeria, nine pearl millet landraces were sampled from two regions: Tidikelt and Hoggar. Some qualitative and quantitative characters of the panicle and grain were measured, as well as in vitro starch digestion of the grain flour. Considerable variation was recorded in seed color, endosperm texture and nutritional value of starch and protein content. In vitro starch digestion displayed a first-order kinetic model. For all pearl millet landraces, starch was digested to a different extent; the hydrolysis index (HI) ranged from 22.29% to 35.52% and the expected glycemic index (eGI) ranged from 27.41 to 38.82. The results show that there is diversity in the physical and chemical properties of pearl millet accessions from the arid areas of Algeria: Tidikelt and Hoggar. This study confirms that pearl millet has an acceptable nutritional value with a low glycemic index suitable for human health and nutrition